Comprehensive Water Resources Management Plan - City of Lakeville

Lakeville Water ResourcesManagement PlanJune 2008Prepared byBarr Engineering Co.

Barr Engineering Company4700 West 77th Street • Minneapolis, MN 55435-4803Phone: 952-832-2600 • Fax: 952-832-2601 • www.barr.com An EEO EmployerMinneapolis, MN • Hibbing, MN • Duluth, MN • Ann Arbor, MI • Jefferson City, MOMemorandumTo:From:Subject:Keith Nelson, P.E., City Engineer, City of LakevilleTim P. Brown, P.E., Barr Engineering CompanyFinal Lakeville Water Resources Management PlanDate: June 9, 2008The Lakeville Water Resources Management Plan (WRMP) presented here has incorporated allof the elements and revisions as required by the Metropolitan Council, the Vermillion RiverWatershed Joint Powers Organization (VRWJPO), and the Black Dog Watershed ManagementOrganization (BDWMO) and has received final approval from the VRWJPO, the BDWMO, andfrom the Metropolitan Council as an element of the Lakeville Comprehensive Plan.Appendix I of the WRMP presents the written approvals and itemizes the revisions made to theWRMP to satisfy the WMO requirements. Comments received on the WRMP from surroundingcommunities have also been received and incorporated where appropriate.This WRMP meets the requirements of Minnesota Statutes 103B.235 and Minnesota Rules 8410,the requirements of the VRWJPO and BDWMO, and the Metropolitan Council requirements andguidelines, and is ready for final action by the Lakeville City Council.Please contact me at 952-832-2838 or tbrown@barr.com with any questions regarding theWRMP.P:\Mpls\23 MN\19\2319A29 Lakeville Stormwater Plan Revisions\WorkFiles\InProgress\Review comments response\LakevilleWRMP final cover memo.doc

City of LakevilleWater Resources Management PlanTable of ContentsExecutive Summary 0-11.0 Introduction 1-11.1 Location and History 1-11.2 Purpose & Scope 1-31.3 Regulatory Background and History 1-31.4 Need for the Plan 1-51.5 Water Resources-Related Agreements 1-61.6 Plan Organization 1-61.7 Plan Update and Amendment Procedures 1-82.0 Goals and Policies 2-12.1 Introduction 2-12.2 Water Quality 2-12.3 Water Quantity 2-42.4 Groundwater 2-62.5 Wetlands and Habitat 2-82.6 Floodplains 2-102.7 Open Space and Recreational Areas 2-112.8 Land Use Management 2-132.9 Education 2-133.0 Lakeville Physical Environment 3-13.1 Land Use 3-13.2 Climate and Precipitation 3-23.3 Topography 3-63.4 Watersheds and Drainage Patterns 3-73.4.1 Orchard Lake Stormwater District 3-83.4.2 Crystal Lake Stormwater District 3-83.4.3 North Creek Stormwater District 3-93.4.4 Farmington Outlet Stormwater District 3-103.4.5 Lake Marion Stormwater District 3-103.4.6 South Creek Stormwater District 3-113.5 Soils 3-123.6 Geology and Groundwater Resources 3-143.6.1 Groundwater Resources 3-153.6.1.1 Surficial (Quaternary) Aquifers 3-153.6.1.2 Bedrock Aquifers 3-15Lakeville Water Resources Management PlanTable of Contents i

3.7 Forest Resources and Native Vegetation 3-163.8 MDNR Public Waters 3-173.9 Wetlands 3-173.9.1 Wetlands by Stormwater District 3-173.10 Surface Water System 3-193.10.1 Lakes 3-193.10.2 Streams 3-203.11 Water Quality 3-213.11.1 Water Quality Sampling Program 3-213.11.1.1 Citizen Assisted Monitoring Program (CAMP) 3-213.11.1.2 Wetland Health Evaluation Program (WHEP) 3-213.11.1.3 Vermillion River Watch 3-213.11.1.4 City Lake Monitoring 3-223.11.2 Water Quality Data summary 3-223.11.2.1 Crystal Lake 3-223.11.2.2 Lee Lake 3-263.11.2.3 Orchard Lake 3-283.11.2.4 Kingsley Lake 3-313.11.2.5 Lake Marion 3-323.11.2.6 Valley Lake 3-353.11.2.7 North Creek 3-383.11.2.8 South Creek 3-383.12 Water Quantity/Flooding 3-533.12.1 Flood Insurance Studies 3-533.13 Recreational Areas 3-533.14 Fish and Wildlife Habitat 3-543.15 Unique Features and Scenic Areas 3-553.16 Pollutant Sources 3-554.0 Stormwater System District Analysis 4-14.1. City of Lakeville Pipe Network 4-14.2. Crystal Lake District 4-14.2.1 PONDNET Modeling of Crystal Lake District 4-34.2.2 PONDNET Modeling of Lee Lake 4-34.2.3 Flood Protection 4-44.2.4 Subwatershed Descriptions 4-54.3. Orchard Lake District 4-94.3.1 PONDNET Modeling of Orchard Lake District 4-104.3.2 Flood Protection 4-124.3.3 Subwatershed Descriptions 4-134.4. Marion Lake District 4-174.4.1 PONDNET Modeling of Marion Lake District 4-184.4.2 Flood Protection 4-204.4.3 Subwatershed Descriptions 4-214.5. North Creek District 4-264.5.1 PONDNET Modeling of North Creek District 4-284.5.2 Flood Protection 4-28Lakeville Water Resources Management PlanTable of Contents ii

4.5.3 Subwatershed Descriptions 4-294.6. South Creek District 4-314.6.1 PONDNET Modeling of South Creek District 4-324.6.2 Flood Protection 4-334.6.3 Subwatershed Descriptions 4-334.7. Farmington Outlet District 4-394.7.1 PONDNET Modeling of Farmington Outlet District 4-404.7.2 Flood Protection 4-404.7.3 Subwatershed Descriptions 4-415.0 Programs and Regulations 5-15.1 The Role of the City of Lakeville in Water Management 5-15.2 National Pollution Discharge Elimination System (NPDES) Program 5-35.2.1 Loading Assessment and Non-Degradation Report 5-45.2.2 Impaired Waters and TMDL 5-55.3 South Creek Management Plan 5-65.4 Wetland Management Plan 5-165.4.1 Lakeville Ordinance 10-4-12: Wetlands 5-365.5 Lakeville Ordinance Chapter 102 Shoreland Overlay District 5-385.6 Lakeville Ordinance Chapter 101 Flood Plain Overlay District 5-545.7 Lakeville Ordinance 10-4-5: Erosion And Sediment Control 5-695.8 Lakeville Ordinance 10-4-6: Storm Drainage 5-705.9 Lakeville Ordinance 10-4-11: Tree Preservation 5-745.10 Lakeville Ordinance 10-4-7: Protected Areas 5-785.11 Lakeville Ordinance 7-13: Surface Water Management Utility Establishment 5-795.12 Spill Containment Procedure 5-815.13 Watersheds 5-825.13.1 Vermillion River Watershed Joint Powers Organization 5-825.13.1.1 Watershed Summary 5-825.13.1.2 Watershed Goals and Policies 5-835.13.1.3 Capital Improvement Program 5-875.13.2 Black Dog Watershed Management Organization 5-885.13.2.1 Watershed Summary 5-885.13.2.2 Watershed Goals and Policies 5-885.13.2.3 Capital Improvement Program 5-1085.14 Other Agency Responsibilities 5-1106.0 Assessment of Opportunities and Issues 6-16.1 Water Quality Problems and Issues 6-16.1.1 Stormwater Runoff Quality Issues 6-16.1.2 National Pollutant Discharge Elimination System (NPDES)Storm Water Pollution Prevention Plan (SWPPP) 6-26.1.3 Non-Degradation Report 6-36.1.4 Impaired Waters and TMDL Issues 6-56.1.5 Metropolitan Council Issues 6-7Lakeville Water Resources Management PlanTable of Contents iii

6.1.6 City Water Quality Goals 6-86.1.7 Watershed Identified Issues 6-106.1.7.1 Vermillion River Watershed Joint Powers Organization Issues 6-106.1.7.2 Black Dog Watershed Management Organization Issues 6-116.1.8 Vermillion River Tributary Trout Stream 6-176.2 Stormwater Runoff Rates and Volumes Problems and Issues 6-186.2.1 General Issues 6-186.2.2 Floodplain FIRM Modifications 6-206.3 Erosion and Sediment Control Problems and Issues 6-206.3.1 Lake Marion Channel 6-226.4 Adequacy of Existing Programs 6-226.4.1 City Ordinances and Official Controls 6-226.4.2 Education and Public Involvement Program 6-236.4.3 Groundwater Protection 6-256.4.4 Maintenance of Stormwater System 6-256.4.5 Adequacy of Existing Capital Improvement and ImplementationPrograms to Correct Problems 6-276.5 Opportunities 6-307.0 Implementation Program 7-17.1 NPDES Phase II MS4 Permit 7-17.2 Operation and Maintenance of Stormwater Systems 7-47.2.1 Need and frequency for sweeping 7-47.2.2 Need and frequency for inspecting and maintaining infrastructure 7-47.2.3 Adequacy of maintenance program 7-47.3 Education and Public Involvement Program 7-57.4 Funding of Implementation Program 7-67.5 Design Standards 7-77.6 Ordinance Implementation and Official Controls 7-77.7 Capital Improvement Program and Priorities 7-98.0 References 8-1AppendicesAppendix A:Stormwater System FinancingAppendix B:Modeling Technical Methods And AssumptionsAppendix C:The Lakeville Ms4 SwpppAppendix D:The Lakeville Ms4 Loading Assessment and Non Degradation ReportAppendix E:Lakeville Wellhead Protection ReportAppendix F: 1. Vermillion River Watershed Joint Powers Organization Standards (2008Amended)2. Vermillion River Watershed Joint Powers Organization RulesAppendix G:Bio-Retention, Filtration and Infiltration TechniquesAppendix H:Bio-Retention, Filtration and Infiltration DetailsAppendix I:WMO ApprovalsLakeville Water Resources Management PlanTable of Contents iv

List of FiguresFigure 3.1.1 Lakeville 2006 Land CoverFigure 3.1.2 Lakeville 2020 Land CoverFigure 3.1.3 Lakeville 2030 Land UseFigure 3.3.1 Lakeville ElevationFigure 3.4.1 Lakeville Stormwater DistrictsFigure 3.5.1 Lakeville Soil TypesFigure 3.6.1 Bedrock GeologyFigure 3.6.2 Surficial GeologyFigure 3.8.1 Lakeville Public WatersFigure 3.9.1 Lakeville WetlandsFigure 3.10.1 Lakeville Surface Water SystemFigure 3.11.1 Crystal Lake Water Quality: Total PhosphorusFigure 3.11.2 Crystal Lake Water Quality: Seasonal Secchi Depth PatternsFigure 3.11.3 Crystal Lake Water Quality: Secchi DepthFigure 3.11.4 Lee Lake Water Quality: Secchi DepthFigure 3.11.5 Lee Lake Water Quality: Total PhosphorusFigure 3.11.6 Orchard Lake Water Quality: Total PhosphorusFigure 3.11.7 Orchard Lake Water Quality: Secchi DepthFigure 3.11.8 Kingsley Lake Water Quality: Total PhosphorusFigure 3.11.9 Kingsley Lake Water Quality: Secchi DepthFigure 3.11.10 Lake Marion Water Quality: Total PhosphorusFigure 3.11.11 Lake Marion Water Quality: Secchi DepthFigure 3.11.12 Valley Lake Water Quality: Secchi DepthFigure 3.11.13 Valley Lake Water Quality: Total PhosphorusFigure 3.12.1 Flood Insurance StudyFigure 3.13.1 Recreational Areas and Open SpacesFigure 3.16.1 Pollutant SourcesFigure 4.2.1 Crystal Lake SubwatershedsFigure 4.2.2 Crystal Lake Drainage SystemFigure 4.3.1 Orchard Lake SubwatershedsFigure 4.3.2 Orchard Lake Drainage SystemFigure 4.4.1 Marion Lake SubwatershedsFigure 4.4.2 Marion Lake Drainage SystemFigure 4.5.1 North Creek SubwatershedsFigure 4.5.2 North Creek Drainage SystemFigure 4.6.1 South Creek SubwatershedsFigure 4.6.2 South Creek Drainage SystemFigure 4.7.1 Farmington Outlet SubwatershedsFigure 4.7.2 Farmington Outlet Drainage SystemFigure 5.4.1 Wetland Inventory and ClassificationFigure 5.13.1 Watershed Management Organization BoundariesFigure 6.4.3 Wellhead Protection AreasLakeville Wetland Inventory - D sizeLakeville Water Resources Management PlanTable of Contents v

TablesTable 3.2.1Table 3.2.2Table 3.11.1Table 3.11.2Table 3.11.3Table 3.11.4Table 3.11.5Table 3.11.6Table 3.11.7Table 3.11.8Table 3.11.9Table 3.11.10Table 3.11.11Table 3.11.12Table 3.11.13Table 3.11.14Table 3.11.15Precipitation Summary – Minneapolis/St. Paul AirportSelected Precipitation and Runoff EventsAvailable Water Quality Data for Crystal LakeWater Quality Summary Grades for Crystal LakeAvailable Water Quality Data for Lee LakeWater Quality Summary Grades for Lee LakeAvailable Water Quality Data for Orchard LakeWater Quality Summary Grades for Orchard LakeAvailable Water Quality Data for Kingsley LakeWater Quality Summary Grades for Kingsley LakeAvailable Water Quality Data for Lake MarionWater Quality Summary Grades for Lake MarionAvailable Water Quality Data for Valley LakeWater Quality Summary Grades for Valley LakeAvailable Water Quality Data for North CreekAvailable Water Quality Data for South CreekSummary of Water Quality Data for South CreekTable 4.2.1Table 4.2.2Table 4.2.3Table 4.2.4Table 4.2.5Table 4.2.6Table 4.2.7Table 4.2.8Table 4.2.9Table 4.2.10Table 4.2.11Table 4.2.12Table 4.3.1Table 4.3.2Table 4.3.3Table 4.3.4Table 4.3.5Table 4.3.6Table 4.3.7Table 4.4.1Table 4.4.2Table 4.4.3Table 4.4.4Table 4.4.5Table 4.4.6Table 4.4.7Table 4.5.1Table 4.5.2Crystal Lake PONDNET ResultsLee Lake PONDNET ResultsPredicted Discharges from Hydrologic ModelsCrystal Lake District: Existing Conditions - Hydraulic and Hydrologic ParametersCrystal Lake District: Existing Conditions - Critical Events and Corresponding RunoffCrystal Lake District: Existing Conditions - Peak Discharges and ElevationsCrystal Lake District East: Proposed Plan 1 - Hydraulic and Hydrologic ParametersCrystal Lake District East: Proposed Plan 1 - Critical Events and Corresponding RunoffCrystal Lake District East: Proposed Plan 1 - Peak Discharges and ElevationsCrystal Lake District West: Proposed Case 6 - Hydraulic and Hydrologic ParametersCrystal Lake District West: Proposed Case 6 - Critical Events and Corresponding RunoffCrystal Lake District West: Proposed Case 6 - Peak Discharges and ElevationsOrchard Lake PONDNET ResultsOrchard Lake District: Existing Conditions - Hydraulic and Hydrologic ParametersOrchard Lake District: Existing Conditions - Critical Events and Corresponding RunoffOrchard Lake District: Existing Conditions - Peak Discharges and ElevationsOrchard Lake District: Proposed Conditions - Hydraulic and Hydrologic ParametersOrchard Lake District: Proposed Conditions - Critical Events and Corresponding RunoffOrchard Lake District: Proposed Conditions - Peak Discharges and ElevationsLake Marion PONDNET ResultsLake Marion District: Existing Conditions - Hydraulic and Hydrologic ParametersLake Marion District: Existing Conditions - Critical Events and Corresponding RunoffLake Marion District: Existing Conditions - Peak Discharges and ElevationsLake Marion District: Proposed Conditions - Hydraulic and Hydrologic ParametersLake Marion District: Proposed Conditions - Critical Events and Corresponding RunoffLake Marion District: Proposed Conditions - Peak Discharges and ElevationsNorth Creek District PONDNET ResultsNorth Creek District: Existing Conditions - Hydraulic and Hydrologic ParametersLakeville Water Resources Management PlanTable of Contents vi

Table 4.5.3Table 4.5.4Table 4.5.5Table 4.5.6Table 4.5.7Table 4.6.1Table 4.6.2Table 4.6.3Table 4.6.4Table 4.6.5Table 4.6.6Table 4.6.7Table 4.7.1Table 4.7.2Table 4.7.3Table 4.7.4Table 4.7.5Table 4.7.6Table 4.7.7North Creek District: Existing Conditions - Critical Events and Corresponding RunoffNorth Creek District: Existing Conditions - Peak Discharges and ElevationsNorth Creek District: Proposed Conditions - Hydraulic and Hydrologic ParametersNorth Creek District: Proposed Conditions - Critical Events and Corresponding RunoffNorth Creek District: Proposed Conditions - Peak Discharges and ElevationsSouth Creek District PONDNET ResultsSouth Creek District: Existing Conditions - Hydraulic and Hydrologic ParametersSouth Creek District: Existing Conditions - Critical Events and Corresponding RunoffSouth Creek District: Existing Conditions - Peak Discharges and ElevationsSouth Creek District: Proposed Conditions - Hydraulic and Hydrologic ParametersSouth Creek District: Proposed Conditions - Critical Events and Corresponding RunoffSouth Creek District: Proposed Conditions - Peak Discharges and ElevationsFarmington Outlet District PONDNET ResultsFarmington Outlet District: Existing Conditions - Hydraulic and Hydrologic ParametersFarmington Outlet District: Existing Conditions - Critical Events and Corresponding RunoffFarmington Outlet District: Existing Conditions - Peak Discharges and ElevationsFarmington Outlet District: Proposed Conditions - Hydraulic and Hydrologic ParametersFarmington Outlet District: Proposed Conditions - Critical Events and CorrespondingRunoffFarmington Outlet District: Proposed Conditions - Peak Discharges and ElevationsTable 5.4Table 5.13Wetland Management StrategiesBDWMO Requirements for City Policies and OrdinancesTable 6.1.1Table 6.1.2Table 6.1.6.1Table 6.1.6.2Table 6.4MPCA Impaired Waters Listing CriteriaSummary of the Impaired Waters ListThe City of Lakeville lake classification systemLake Classification and Goals for the City of LakevilleSummary of Stormwater Issues for the City of LakevilleTable 7.7.1Table 7.7.2Table 7.7.3Table 7.7.4Table 7.7.5Table 7.7.6Table 7.7.7Table 7.7.8Table 7.7.9Table 7.7.10Table 7.7.11Table 7.7.12City of Lakeville Water Resources Implementation Program: Capital improvement ProjectsCity of Lakeville Water Resources Implementation Program: StudiesCity of Lakeville Water Resources Implementation Program: Official ControlsCity of Lakeville Water Resources Implementation Program: Public Education, Outreach,and ParticipationCity of Lakeville Water Resources Implementation Program: Lakes Management ProgramCity of Lakeville Water Resources Implementation Program: Operation and MaintenanceCIP Timeline: Capital improvement ProjectsCIP Timeline: StudiesCIP Timeline: Official ControlsCIP Timeline: Public Education, Outreach, and ParticipationCIP Timeline: Lakes Management ProgramCIP Timeline: Operation and MaintenanceLakeville Water Resources Management PlanTable of Contents vii

List of AcronymsBDWMOBIBMPBWSRCAMPChl aCLMPCFSCIPCMPCOECWADNRDODWSMAEAWEISEPAEQBFEMAFIRMFISIBIISTSLALCALCMRLGULOMAMCESMCMMDHMDNRMnRAMMnDOTMPCAMS4sMSLBlack Dog Watershed Management OrganizationBiotic IndexBest Management PracticeMinnesota Board of Water & Soil ResourcesCitizen Assisted Monitoring ProgramChlorophyll aCitizen Lake Monitoring ProgramCubic Feet per SecondCapital Improvement ProgramCorrugated Metal PipeUnited States Army Corps of EngineersClean Water ActMinnesota Department of Natural ResourcesDissolved OxygenDrinking Water Supply Management AreasEnvironmental Assessment WorksheetsEnvironmental Impact StatementUnited States Environmental Protection AgencyMinnesota Environmental Quality BoardFederal Emergency Management AgencyFlood Insurance Rate MapFlood Insurance StudiesIndex of Biotic IntegrityIndividual Sewage Treatment SystemsLoad AllocationLocal Cooperation AgreementLegislative Commission on Minnesota ResourcesLocal Government UnitLetters of Map AmendmentMetropolitan Council Environmental ServicesMinimum Control MeasureMinnesota Department of HealthMinnesota Department of Natural ResourcesMinnesota Rapid Assessment MethodMinnesota Department of TransportationMinnesota Pollution Control AgencyMunicipal Separate Storm Sewer SystemsMean Sea LevelLakeville Water Resources Management PlanList of Acronyms

MSPMUSANCHFNPDESNWINURPOHWPUDPWIRCPSDSSWCDSWMPSWPPPTEPTIFTMDLTPTSITSISDTSSUSDAUSGSUSFWSVICVOCVSMPVRWJPOWCAWCBPWHEPWHPAWHPWLAWMPWMOWOMPWRMPMinneapolis/St. PaulMetropolitan Urban Service AreaNorth Central Hardwood ForestNational Pollutant Discharge Elimination SystemNational Wetlands InventoryNationwide Urban Runoff ProgramOrdinary High Water LevelPlanned Unit DevelopmentPublic Waters InventoryReinforced Concrete PipeState Disposal SystemSoil and Water Conservation DistrictSurface Water Management PlanStorm Water Pollution Prevent PlanTechnical Evaluation PanelTax Increment FinancingTotal Maximum Daily LoadTotal PhosphorusTrophic State IndexTrophic State Index - Secchi DiskTotal Suspended SolidsUnited States Department of AgricultureUnited States Geological SurveyUnited States Fish and Wildlife ServiceVoluntary Investigation and Clean-upVolatile Organic CompoundVolunteer Stream Monitoring ProgramVermillion River Watershed Joint Powers OrganizationWetland Conservation ActWestern Corn Belt PlainsWetland Health Evaluation ProjectWellhead Protection AreaWellhead Protection PlanWaste Load AllocationWetland Management PlanWatershed Management OrganizationWatershed Outlet Monitoring ProgramWater Resources Management PlanLakeville Water Resources Management PlanList of Acronyms

Executive SummaryThe city of Lakeville is located in the southeast corner of the Twin Cities metropolitan areawithin Dakota County. At one time, Lakeville was a rural community that serviced surroundingagricultural activities. In recent years, its convenient access to the metropolitan area hasstimulated both residential and commercial growth. The Metropolitan Council’s April 2006population estimate for Lakeville is 52,323, makingit the third largest city in Dakota County.As its name implies, Lakeville contains severallakes as well as hundreds of smaller ponds andwetlands within its borders. The largest lakesinclude Lake Marion, Orchard Lake, and CrystalLake which are recreational waters used heavily forfishing, boating, and swimming. Smaller namednatural lakes include Kingsley Lake and Lee Lake.Valley Lake is a small man-made lake in thenorthern part of the city.According to statute, the purposes ofwater management programs are to:• Protect, preserve, and use naturalsurface and groundwater storage andretention systems• Minimize public capital expendituresneeded to correct flooding and waterquality problems• Identify and plan for means toeffectively protect and improve surfaceand groundwater quality• Establish more uniform local policiesA branch of the Vermillion River flows throughLakeville. Its headwaters are just west of the citylimits in Credit River Township, and it flowseastward across Dakota County until it emptiesinto the Mississippi River at the Wisconsin border.••and official controls for surface andgroundwater managementPrevent erosion of soil into surfacewater systemsPromote groundwater rechargeMuch of Lakeville drains into the Vermillion River • Protect and enhance fish and wildlifehabitat and water recreational facilitieswatershed. North Creek, a major tributary of the• Secure the other benefits associatedVermillion, begins its flow in northern Lakevillewith proper management of surface andand flows eastward to meet the Vermillion nearground waterdowntown Farmington just east of Lakeville. Partsof the Vermillion River within Lakeville have beendesignated as a trout stream by the Minnesota Department of Natural Resources.This WRMP will guide the City of Lakeville in protecting, preserving, and managing its surfacewater resources and stormwater system. This plan meets the requirements of MinnesotaStatutes 103B.235, Minnesota Rules Chapter 8410, and the watershed organizations withjurisdiction in the city: the Vermillion River Watershed Joint Powers Organization (VRWJPO)and the Black Dog Watershed Management Organization (BDWMO). The purpose of this WRMPincludes those purposes given in Minnesota Statute 103B.201 for metropolitan watermanagement programs.Lakeville Water Resources Management Plan Page 0-1

This WRMP was submitted for review to the Vermillion River Watershed Joint PowersOrganization; the Black Dog Watershed Management Organization; Dakota County; the ScottCounty Watershed Management Organization; the Metropolitan Council; the MinnesotaDepartment of Health; the Dakota County Soil and Water Conservation District; the ScottCounty Watershed Management Organization; and adjacent cities, townships, and schooldistricts. All comments were addressed either as plan revisions or oral/written clarification forthe reviewers.The City’s NPDES-MS4 Permit requirements have led to the following specific requirements forthe city of Lakeville:1. Preparation of the MS4 General Storm Water Permit Application and Storm WaterPollution Prevention Program2. Preparation of a Loading Assessment and Nondegradation Report3. Preparation of this Water Resources Management Plan (WRMP)4. Preparation of future updates to the MS4 permit and WRMP to address the requirementsof future total maximum daily load (TMDL) analysesAs well as meeting the requirements of its NPDES-MS4 Permit, the City of Lakeville actively andprogressively manages stormwater to protect life, property, waterbodies within the city, andreceiving waters outside the city. The following summarizes the City’s long- and short-termgoals toward continuing that protection along with the policies that will move the City towardmeeting those goals. Section 2 of the plan presents detailed objectives and actions along withthese goals and policies.Lakeville Water Resources Management Plan Page 0-2

WaterQualityGoalProtect and enhance surface water quality in the city of Lakeville2.2.1 The City of Lakeville will be responsible for effectively managingstormwater. Responsibility for enforcing water quality and stormwatermanagement standards will be assumed by the City of Lakeville.Water Quality Policies2.2.2 The City of Lakeville supports and promotes a reduction in runoff ratesdue to new development.2.2.3 Use of existing natural retention and detention areas for stormwatermanagement to maintain or improve existing water quality will be achieved to theextent possible.2.2.4 Land use planning, policies and controls that maintain sustainable, highqualitysurface water resources are supported by the City of Lakeville.2.2.5 The City of Lakeville intends to meet or exceed all water relatedregulations that apply as promulgated by the Federal Government, the State ofMinnesota, Dakota County, the Vermillion River Watershed Joint PowersOrganization (VRWJPO), the Black Dog Watershed Management Organization(BDWMO) and the Metropolitan Council.WaterQuantityGoalManage the rate and volume of runoff entering rivers, streams, lakes andwetlands within the city of Lakeville2.3.1 A reduction in runoff volumes will be supported and promoted.Water Quantity Policies2.3.2 Use of existing natural retention and detention areas for stormwatermanagement to minimize flow rates will be encouraged.2.3.3 The City will continue implementation of the South Creek ManagementPlan.2.3.4 Stormwater will be managed to minimize erosion.2.3.5 Outlets from landlocked basins will be allowed, only when such outlets areconsistent with State and federal regulations, and the downstream impacts,riparian impacts, and habitat impacts of such outlets have been analyzed and nodetrimental impacts result.2.3.6 The Orchard Lake outlet will continue to restrict peak outflow to no morethan 65 c.f.s. for the 100 year, 24 hour runoff event, per BDWMO requirement.Lakeville Water Resources Management Plan Page 0-3

GroundwaterGoalProtect groundwater quality and quantity to preserve it for sustainableand beneficial purposesGroundwaterPolicies2.4.1 Groundwater quality should not be sacrificed to manage surfacewater. Holding ponds, wetlands and other water storage areas must bedesigned to protect groundwater.2.4.2 Infiltration of stormwater and resulting groundwater recharge will bepromoted where it is feasible and does not pose a threat to groundwaterquality.WetlandsandHabitatGoalsMaintain and enhance, where possible, the functions and values of existingwetlands and habitats within the cityPromote the restoration and/or creation of wetlands2.5.1 The City of Lakeville will work to achieve no net loss of wetland quantity,quality and biological diversity.2.5.2 Wetland replacements will provide equal or greater functions and values atthe replacement ratio dictated by the Lakeville Wetland Management Plan.Wetlands and Habitat Policies2.5.3 Avoidance of direct or indirect wetland disturbance will be required for alldevelopments and land disturbing activities, in accordance with State and federalrequirements and the Lakeville Wetland Management Plan.2.5.4 Buffers, acting as filter strips, will be required around every wetland basedon the Lakeville Wetland Management Plan.2.5.5 Wetlands will be protected from chemical, physical, biological, orhydrological changes so as to prevent significant adverse impacts to the followingdesignated wetland uses: maintaining biological diversity, preserving wildlifehabitat, providing recreational opportunities, erosion control, groundwaterrecharge, low flow augmentation, stormwater retention, stream sedimentation,and aesthetic enjoyment, as specified in Minnesota Rules 7050.2.5.6 Fragmentation of natural areas and corridors will be avoided whenfeasible.2.5.7 Impacts to locally and regionally significant natural areas will be avoidedwhen feasible or mitigated when possible.2.5.8 High priority natural areas identified through the land cover mappingdone for the Dakota County Farmland & Natural Area Program, the DakotaCounty Biological Survey and other inventories will be used to assist in evaluatingdevelopment proposals.Lakeville Water Resources Management Plan Page 0-4

FloodplainsGoalManage and protect the floodplains of the city from encroachment2.6.1 The natural function of the floodplain as a floodwater storage areashould be protected from encroachment.2.6.2 The City will work to maintain no net loss of floodplain storage.Floodplains Policies2.6.3 Floodplains will be managed to maintain critical 100-year flood storagevolumes.2.6.4 The City will work to restrict construction of new structures to sitesabove the regulatory flood protection elevation.2.6.5 Floodplain zoning regulations will be consistent with Dakota Countywater resource plans and ordinances.2.6.6 Upstream floodwater storage should be maximized.2.6.7 Accumulated sediment should be removed from flood storage facilitiesprior to reaching 50 percent of the storage area’s capacity.2.6.8 Infiltration in appropriate floodplain areas should be increasedthrough increased vegetated areas and reduced impervious surfaces.Open SpaceandRecreationalAreas GoalDevelop or improve recreational, fish and wildlife, open space areas andaccessibility in conjunction with water quality improvement projectsOpen Space and RecreationalAreas Policies2.7.1 Recreational uses of waterbodies that are a threat to human health willnot be promoted by the City of Lakeville.2.7.2 Impacts to regionally and locally important natural areas should beavoided or mitigated.2.7.3 Fragmenting natural areas and natural/wildlife corridors should beavoided or minimized.2.7.4 Creation and preservation of navigational and wading access to publicwaters will be sought, where appropriate.2.7.5 Natural areas, shoreland and wetland environments will be preserved,restored and enhanced wherever possible.2.7.6 Use of native vegetation should be considered for local governmentprojects and private development open spaces.Lakeville Water Resources Management Plan Page 0-5

Open SpaceandRecreationalAreas Policies2.7.7 Existing open spaces, outdoor recreational amenities, and culturalresources will be connected and enhanced whenever possible.2.7.8 Open space uses in wellhead protection areas will be encouraged andpromoted.2.7.9 Efforts to create a continuous trail system along the Vermillion Riverand its major tributaries will be supported.Land UseManagementGoalProtect and conserve water resources by promoting sustainable growth,integrated land use and land use planning, and water resourcemanagementLand UseManagementPolicies2.8.1 The presence of environmentally sensitive natural resource areasshould guide land use management decisions.2.8.2 The impacts of land disturbing activities on water resources,including cumulative impacts, should be considered for each proposedactivity before the activity occurs.2.8.3 Stormwater best management practices must be identified as part ofthe development approval process.EducationalGoalOffer programs, educational opportunities and information that facilitate anunderstanding of water resource issues in the city of Lakeville anddownstreamEducationalPolicy2.9.1 The City of Lakeville will provide support where appropriate, for thedevelopment and distribution of educational materials and assist otheragencies efforts.Lakeville Water Resources Management Plan Page 0-6

Section 6 of this plan presents issues and challenges that face the City in its stormwatermanagement program. The following table summarizes these issues.CATEGORYNPDES StormwaterPollution PreventionPlan (SWPPP)Nondegradation PlanImpaired Waters♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦ISSUEPublic education & outreachPublic participationIllicit discharge detection and eliminationConstruction site runoff controlPost construction stormwater managementPollution prevention/housekeepingDetermination of no prudent/feasible alternatives to discharge torestricted watersEvaluation of infiltration within source water protection areasInfiltration standardUpdate ordinances to conform with VRWJPO StandardsStream corridor buffersEducation on buffers and illicit dischargeSpill prevention, inspection and response planProhibit infiltration in 1 year travel zone at well head protectionplan (WHP)Tracking best management practice (BMP) implementationLee LakeCrystal LakeNorth CreekSouth CreekTMDL developmentLakeville Water Resources Management Plan Page 0-7

CATEGORYVRWJPOBDWMOMet Council♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦♦ISSUERiver flow volumes have increasedSurface water quality is threatened or impairedVermillion River corridor is threatened or impairedSensitive resources are present and/or threatened or impairedGroundwater quality is threatened or impairedAdditional development is expectedData for informed decisions is limitedPublic awareness about water resources in the watershed andappropriate stewardship is limitedInter-community flood controlFuture discharge limits at city boundariesVRWJPO policies and standardsCrystal Lake flooding and water quality goalsKingsley Lake water quality goalsOrchard Lake outflow rate and water quality goalsStormwater runoff water qualityIntercommunity flood controlWetland protectionWater resources educationMember accountability and evaluationReduction of stormwater volumeIncrease stormwater qualityMaximize infiltrationThermal pollutionWetland managementNondegradation goalsWater quality goalsLakeville Water Resources Management Plan Page 0-8

City Issues♦♦♦♦♦♦♦Retain permitting authority within the VRWJPO areaReview/revise ordinances for consistency with VRWJPO andBDWMO StandardsFuture city-wide hydraulic modelingFloodplain modificationsErosion at ravine west of Lake MarionTracking BMP implementationStormwater system maintenanceSection 7 of this plan describes the significant components of the City’s WRMP implementationprogram, including its NPDES Phase II MS4 permit, operation and maintenance of itsstormwater system, education and public involvement, funding, ordinance implementation andofficial controls, and implementation priorities. The implementation program details arepresented at the end of Section 7. The tables present summary details of the implementationprogram, including a project description, cost estimate, potential funding sources, and proposedyears of implementation from 2008-2017. Highlights of implementation tasks include:1. NPDES-MS4 Permit requirements including all the components of the City’s SWPPP, theNondegradation Report implementation items, and future TMDL requirements.2. Review and revision of the City’s development- and stormwater-related ordinances tomeet the standards of the VRWJPO and BDWMO Water Management Plans and officialStandards.3. Stormwater-related capital improvements.4. A comprehensive education program.5. Extensive operational and maintenance activities.Lakeville Water Resources Management Plan Page 0-9

Section 1.0 IntroductionAs its name implies, Lakeville contains several important lakes as well as hundreds of smallerponds and wetlands within its borders. The two largest lakes, Lake Marion and Orchard Lake,are heavily used recreational waters utilized for fishing, boating, and swimming. A portion ofCrystal Lake, another an important local resource, also lies within Lakeville. Smaller namednatural lakes include Kingsley Lake and Lee Lake. Valley Lake is a small man-made lake in thenorthern part of the city.A branch of the Vermillion River flows through Lakeville. Its headwaters are just west of the citylimits in Credit River Township, and it flows eastward across Dakota County until it empties intothe Mississippi River. Much of Lakeville drains into the Vermillion River watershed. NorthCreek, a major tributary of the Vermillion, begins its flow in northern Lakeville and flowseastward to meet the Vermillion near downtown Farmington just east of Lakeville. Parts of theVermillion River within Lakeville have been designated as a trout stream by the MinnesotaDepartment of Natural Resources.1.1 LOCATION AND HISTORYLakeville is located within Dakota County in the southeast corner of the Twin Cities metropolitanarea, 20 miles south of downtown Minneapolis and St. Paul. Major transportation corridors allowaccess along I-35, with interchanges at County Road (CSAH) 46, County Road (CSAH) 50, 185th St.W., and County Road (CSAH) 70. Access is also available on the east via Cedar Ave.At one time Lakeville was a rural community that servicedsurrounding agricultural activities. In recent years, itsconvenient access to the metropolitan area has stimulatedboth residential and commercial growth. Located betweenurban and rural service areas, Lakeville maintains a historicdowntown neighborhood and other mature residential areas.Lakeville FactsFounded 1853Total area 38 square milesPopulation over 50,000Lakeville had its origins in 1853 when Captain William B. Dodd, who came from the east to servethe military forts in the Minnesota Territory, designed and directed the construction of a roadthat would serve as a practical land route connecting the military forts in St. Paul to the southernforts. The road, which was named for Captain Dodd after he was killed in the Sioux uprising in1862, bisects present-day Lakeville.J.J. Brackett, who owned a St. Paul lumber mill and transported mail, supplies, and travelersalong this route, soon chose Lakeville as an ideal site for a town because it was roughly halfwayLakeville Water Resources Management Plan Page 1-1

etween St. Paul and St. Peter. In 1855 he platted 250 acres and named it Lakeville because itbordered the nearby Prairie Lake (Lake Marion). By 1858 Lakeville contained a general store,two hotels, a boarding house, a blacksmith shop, a saloon, and a shoemaker shop.Lakeville Township, which encompassed the rural area around the tiny town of Lakeville, wasofficially formed as a governing unit in 1858. A variety of ethnic groups settled in the Lakevillearea in the early years, including immigrants from Ireland, Scotland, England and theScandinavian countries.When the Hastings and Dakota Railroad was built near the tiny village of Lakeville in 1869,railroad officials tried to buy land for a depot froma Scotsman who refused to sell. The railroadthen bought 20 acres one-half mile east, put up aplatform and named this area Fairfield. It wasn'tlong before existing businesses moved from theoriginal town site to Fairfield, and new businesseswere established at the new town site. For nineyears, business owners and residents tried to getFairfield's name changed to Lakeville. In 1878,they decided they wanted a government separatefrom the township and sought incorporation as theVillage of Lakeville.In 1910, Colonel Marion Savage and severalpartners had a dream that resulted in building anamusement park, along with a railroad line thatconnected the park with the Twin Cities. Theylocated their park on the east shore of the thenPrairie Lake, renaming it Lake Marion afterColonel Savage. Antlers Amusement Park becameone of the most famous amusement parks in theupper Midwest. The amusement park declined inpopularity in the 1920s and 1930s due to aAccording to statute, the purposes ofwater management programs are to:combination of factors - the advent of the automobile, the Great Depression, and several dryyears that saw Lake Marion drop to its lowest level ever (Lakeville Area Historical Society,2004).Protect, preserve, and use naturalsurface and groundwater storage andretention systemsMinimize public capital expendituresneeded to correct flooding and waterquality problemsIdentify and plan for means toeffectively protect and improve surfaceand groundwater qualityEstablish more uniform local policiesand official controls for surface andgroundwater managementPrevent erosion of soil into surfacewater systemsPromote groundwater rechargeProtect and enhance fish and wildlifehabitat and water recreational facilitiesSecure the other benefits associatedwith proper management of surface andground waterAirlake Industrial Park, which is now home to more than 100 businesses and employs 4,000people, opened in 1967. At the same time, most of Lakeville Township merged with the Villageof Lakeville to become the 38-square-mile city of Lakeville. Just prior to the merger, LakevilleTownship included 2,100 residents, while the village was home to just under 1,000. By 1970,Lakeville's population had grown to 7,557. The population doubled from 1970 to 1980, anddoubled again from 1980 to 1992. The current population is more than 50,000. Lakeville isLakeville Water Resources Management Plan Page 1-2

expected to become the largest city in Dakota County by the year 2020 with a population ofabout 78,400.1.2 PLAN PURPOSE &SCOPEThe City of Lakeville’s Water Resources Management Plan (WRMP) is a local water managementplan prepared in accordance with Minnesota Statute 103B.235 and Minnesota Rules 8410. Thepurpose of this WRMP includes those purposes given in Minnesota Statute 103B.201 formetropolitan water management programs.This WRMP will guide the City of Lakeville in protecting, preserving, and managing its surfacewater resources and stormwater system. This plan meets the requirements of MinnesotaStatutes 103B.235, Minnesota Rules Chapter 8410, and the watershed organizations withjurisdiction in the city: the Vermillion River Watershed Joint Powers Organization (VRWJPO)and the Black Dog Watershed Management Organization (BDWMO).1.3 REGULATORY BACKGROUND AND HISTORYAlong with the purposes and requirements outlined in state statutes and rules, this WRMPreflects numerous other water resource-related state and federal mandates that the City mustmeet. As state and federal laws have changed over the years, the role of the City in waterresource management has also changed. The following paragraphs provide the background andhistory of some of these mandates (references: “Minnesota Environment,” Minnesota PollutionControl Agency (MPCA), Volume 7, Number 1 – Summer 2007, the MPCA’s websitewww.pca.state.mn.us, and the City of Plymouth’s July/August 2007 edition of “EnvironmentalExtra”).In 1945, the Minnesota State Legislature authorized a new state Water Pollution ControlCommission because too many communities were dumping raw sewage into lakes and rivers.One of the Commission’s jobs was to encourage communities to build wastewater treatmentplants to stop the flow of raw sewage into rivers and lakes. Three years later, in 1948, theUnited States (U.S.) Congress enacted the Federal Water Pollution Control Act (FWPCA), inresponse to the threat that polluted water posed to the public health and welfare.In 1967, the Minnesota Legislature created the Minnesota Pollution Control Agency, inresponse to oil spills and other major environmental incidents. Its mission was to protect theair, land, and waters of the state.Five years later, in 1972, the U.S. Congress enacted amendments to the FWPCA to address thegrowing public awareness and concern for controlling water pollution. This act became knownas the Clean Water Act (CWA). Amendments to the CWA in 1977 addressed “point source”Lakeville Water Resources Management Plan Page 1-3

facilities, such as municipal sewage plants and industrial facilities. The National PollutantDischarge Elimination System (NPDES) became the program for regulation of point sourcepollution. As a “delegated permitting authority,” the MPCA issues combined State DisposalSystem (SDS) and NPDES stormwater permits.In 1987, the Minnesota Legislature enacted laws to control polluted runoff, broadeningattention from “point” source to “nonpoint” source pollution, which is the movement ofpollutants from land to water, typically in stormwater or snowmelt runoff from streets, lawns,construction sites, farms, etc. Also in 1987, state regulatory authority for this program wasdelegated from the U.S. Environmental Protection Agency (EPA) to the MPCA. In 1987, anamendment to the federal Clean Water Act required implementation of a two-phasecomprehensive national program to address stormwater runoff.In 1990, the EPA promulgated regulations establishing the Phase I Stormwater Program. ThePhase I federal regulations required two general categories of stormwater discharges to becovered under a NPDES stormwater permit: 11 regulated categories of industrial activityincluding construction activity that disturbs five or more acres of land, and municipal separatestorm sewer systems (MS4s) serving populations of 100,000 or more (including Minneapolisand St. Paul).In 1994 and 1995, the MPCA promulgated rules to establish the Phase I Stormwater Programat the state level. Under Phase I, Minneapolis and St. Paul obtained individual permits anddesigned and implemented stormwater programs. By 1999,the Phase II federal regulationswere promulgated, which expanded the scope of the NPDES Stormwater Program to includesmaller MS4s in urbanized areas, construction activities that disturb between one and fiveacres of land, and smaller municipally owned industrial activities. The MPCA thenpromulgated rules related to the Phase II federal regulations to fulfill federal NPDESdelegation responsibilities. The rules establish the NPDES stormwater permit requirementsfor regulated MS4s, construction, and industrial activities.In 2002, the MPCA began identifying surface water resources that are impaired for theiridentified uses such as swimming and aquatic habitat. As required by the Clean Water Act, if awater body is included on the impaired waters list, it triggers an analysis called a totalmaximum daily load (TMDL) study. The TMDL analysis determines the impaired water body’scapacity to assimilate specific pollutants and still meet water quality standards. A TMDL alsodevelops an allocation scheme among the various contributors—point sources, nonpointsources and natural background—as well as a margin of safety. Section 303(d) of the CWArequires each state to identify and establish priority rankings for waters that do not meet thewater quality standards. The list of impaired waters, sometimes called the 303(d) list, isupdated by the states every two years.Then in 2003, Phase II of the NPDES program began. Phase II is a broader program thatincludes smaller construction sites, municipally owned or operated industrial activity, andLakeville Water Resources Management Plan Page 1-4

many more municipalities (MS4s). Regulated parties under the Phase II program mustdevelop stormwater pollution prevention plans to address their stormwater discharges, anddetermine the appropriate pollution prevention practices or “best management practices” tominimize pollution for their specific site. Each of the three permit types—construction,industrial, MS4—has distinct requirements and some regulated parties may require more thanone permit. In the same year, the MPCA issued a General Permit for municipalities withpopulations over 10,000 (MS4 permit), including Lakeville. The permit requires cities tocomply with six “minimum control measures,” which include public education, publicoutreach, illicit discharge detection and elimination, construction site stormwater runoffcontrol, post-construction stormwater management, and pollution prevention/goodhousekeeping measures. Approximately 200 MS4s in Minnesota were mandated by the PhaseII federal regulations as requiring NPDES permit coverage; these include municipalitieslocated within the boundaries of an urbanized area.In 2006, the MPCA issued a new MS4 General Permit. The new permit identifies a group of30 selected MS4s that must complete a Loading Assessment and a Nondegradation Report aspart of their MS4 Storm Water Permits. These MS4s must assess the volume of totalsuspended solids (soil, sand, and silt), phosphorus, and water in stormwater runoff andestablish a non-degradation plan to keep pollutant loadings at 1988 levels. The city ofLakeville is part of this group.1.4 NEED FOR THE PLANThe above regulations and requirements have led to the following specific requirements for thecity of Lakeville and other similar cities:Preparation of the MS4 General Storm Water Permit Application and Storm WaterPollution Prevention ProgramPreparation of a Loading Assessment and Nondegradation Report (required by MS4permit)Preparation of this Water Resources Management Plan (WRMP)Preparation of future updates to the MS4 permit and WRMP to address the requirementsof future TMDL analysesLakeville Water Resources Management Plan Page 1-5

1.5 WATER RESOURCES-RELATED AGREEMENTSThe City of Lakeville has entered into the following water resource related joint powersagreements.The City of Lakeville has entered into the Joint Powers Agreement establishing the Black DogWatershed Management Organization (BDWMO). The original joint powers agreement betweenthe five member cities (including Lakeville) went into effect in 1985. In 1999, the Dakota Countyportion of the Credit River WMO was added to the BDWMO and the member cities executed arevised and restated joint powers agreement, and the BDWMO and Scott County signed amemorandum of understanding regarding the management of the Credit River portion of theBDWMO.The original 1982 Joint Powers Agreement establishing the Vermillion River WatershedManagement Organization included the City of Lakeville along with 20 other units ofgovernment. In August 2002 this agreement was terminated and Scott County and DakotaCounty agreed on the joint administration and implementation of the former Vermillion RiverWMO Watershed Management Plan. The counties formed a Joint Powers Organization toexercise leadership in the development of policies, programs, and projects that will protect andpreserve the water resources in the Vermillion River Watershed. While the VRWJPOjurisdiction includes most of Lakeville, the City is not currently a direct party to this agreement.Lakeville has entered a Joint Powers Agreement with the City of Burnsville, dated January 3,1992 relating to three issues:1. Quarterly potable water usage2. Maple Island Sanitary Sewer Lift Station charges3. Payment for the Crystal Lake Outlet constructionLakeville has entered a Joint Powers Agreement with the City of Burnsville, dated March 17,1980 relating to the Crystal Lake Overflow System.Lakeville has entered a Joint Powers Agreement with the City of Burnsville, dated September 6,1983 relating to storm controls in an area adjacent to a common border between the cities ofLakeville and Burnsville in the vicinity of I35 northbound and 160th Street.1.6 PLAN ORGANIZATIONThe Lakeville Water Resources Management Plan (WRMP) sets the course for the City’smanagement of the water resources and stormwater within the city. The WRMP sets goals andpolicies for the city and its resources, provides data and other background information, outlinesLakeville Water Resources Management Plan Page 1-6

the applicable regulations, assesses city-wide and specific issues, and lists implementation tasksto achieve the goals. The WRMP also provides information regarding the funding of theimplementation program. The WRMP is organized into six major sections, summarized asfollows:Executive SummaryThe Executive Summary provides basic information about the city’snatural setting and summarizes the highlights of the WRMP, includingthe WRMP purpose and scope, goals, policies, and implementation tasks.Section 1.0IntroductionThis section provides general background on the city’s history and thebackground for the plan itself, including the regulatory history andrelated jurisdictional issues.Section 2.0Goals and PoliciesSection 2 presents the City’s water resource vision in the form of its goalsand policies.Section 3.0Lakeville Physical EnvironmentSection 3 provides technical information describing the surface andsubsurface conditions of the city. Most of Section 3 presents a city-wideinventory, including land use, climate and precipitation, topography,soils, geology, groundwater, MDNR public waters, wetlands, surface waterresource monitoring information, floodplain information, unique featuresand scenic areas, pollutant sources, and major basins and overall drainagepatterns.Section 3 also includes a number of maps, such as city-wide maps of landuse, MDNR public waters, wetlands, and drainage basins, and mapsshowing the drainage patterns for each major drainage basin. Thissection also includes a number of tables, such as precipitationinformation, and water quality information.Section 4.0Stormwater System District AnalysisThis section presents the hydrologic and water quality modelingperformed to analyze the City’s systematic needs regarding stormwaterquantity and quality management. This modeling was done in 1995 andwill be updated as part of the implementation of this plan.Lakeville Water Resources Management Plan Page 1-7

Section 5.0Programs and RegulationsSection 5 is organized to present the state, regional, and local programsand regulations that apply to water resource management in Lakeville.This is intended to be a resource for City staff, residents, and developersliving and working in Lakeville.Section 6.0Assessment of Issues and ProblemsSection 6 assesses the issues, challenges, and problems the City faces inmanaging stormwater on behalf of the public. City-wide and specificissues and problems are presented and discussed. This section discussesthe adequacy of the City’s ordinances and official controls, the City’sclassification system, the City’s education and public involvementprogram, maintenance of the stormwater system, groundwater protection,and the City’s funding programs.Section 7.0Implementation ProgramSection 7 describes the significant components of the City’s WRMPimplementation program, including its NPDES Phase II MS4 permit,operation and maintenance of its stormwater system, education andpublic involvement, funding, ordinance implementation and officialcontrols, implementation priorities, and a detailed implementation plan.Section 8.0ReferencesThis section lists the documents and other references used in thepreparation of the WRMP.1.7 PLAN UPDATE AND AMENDMENT PROCEDURESThis Water Resources Management Plan (WRMP) will guide the City of Lakeville’s activitiesthrough 2017, or until superseded by adoption and approval of a subsequent WRMP. The Citywill begin the process of updating this plan one to two years before its expiration date. Theupdated plan will meet the requirements of the applicable Minnesota laws and rules, theVRWJPO, and the BDWMO.The City may revise this WRMP through an amendment prior to updating the plan, if eitherminor changes are required, or if problems arise that are not addressed in the WRMP. However,this WRMP remains in full force and effect until an updated WRMP is approved by the VRWJPOand the BDWMO.Lakeville Water Resources Management Plan Page 1-8

Any significant changes to this WRMP must be approved by both the VRWJPO and the BDWMO.Minor changes to this WRMP will not require WMO approval and can be made by City staff, butmust be supplied to the WMOs for their information. The City considers minor changes thosethat do not modify the goals, policies, or commitments identified in the WRMP. Examples ofminor changes include:Inclusion of new or corrected hydrologic modeling results and mapping, as long as thechanges do not significantly affect the rate or quality of intercommunity stormwaterrunoffInclusion of new/updated water quality monitoring dataMinor changes to the City’s implementation program, such as added projects, schedulechanges, and revised cost estimates, as long as there are no intercommunity impacts ofsuch changes and the changes stem from the goals and policies in the WRMPIf it is unclear whether a proposed WRMP change is minor or not, the City will bring the issue tothe BDWMO and the VRWJPO for their determination.The City’s amendment procedure for significant changes to the WRMP is as follows:1. City staff preparation and review of WRMP amendment2. City council consideration of WRMP amendment. The City council would either approvesubmittal of the amendment for WMO review and approval, or decide not to moveforward with the amendment. If the City council decides to submit the amendment forWMO approval, the council would also need to determine when/if a public hearing orother public process should be undertaken.3. Submittal of proposed WRMP amendment to the VRWJPO, and the BDWMO for reviewand approval. The City must also submit the proposed WRMP amendment to theMetropolitan Council and Dakota County. The review process for a WRMP amendmentis the same as for the original WRMP. The WMOs have 60 days to review and commenton the proposed WRMP amendment.4. City council adoption of WRMP amendment, after WMO approval of the WRMPamendmentLakeville Water Resources Management Plan Page 1-9

Section 2.0 Goals and Policies2.1 INTRODUCTIONThe City of Lakeville actively and progressively manages stormwater to protect life, property,waterbodies within the city, and receiving waters outside the city. This plan section presents theCity’s long and short term goals toward continuing that protection.2.2 WATER QUALITYGoalProtect and enhance surface water quality in the city of Lakeville2.2.1 The City of Lakeville will be responsible for effectively managing stormwater.Responsibility for enforcing water quality and stormwater management standards willbe assumed by the City of Lakeville.2.2.2 The City of Lakeville supports and promotes a reduction in runoff rates due tonew development.Policies2.2.3 Use of existing natural retention and detention areas for stormwatermanagement to maintain or improve existing water quality will be achieved to theextent possible.2.2.4 Land use planning, policies and controls that maintain sustainable, high-qualitysurface water resources are supported by the City of Lakeville.2.2.5 The City of Lakeville intends to meet or exceed all water related regulations thatapply as promulgated by the Federal Government, the State of Minnesota, DakotaCounty, the Vermillion River Watershed Joint Powers Organization (VRWJPO), theBlack Dog Watershed Management Organization (BDWMO) and the MetropolitanCouncil.Surface Water Quality ObjectivesOBJECTIVE 1 – Maintain or improve water quality of lakes, streams, and wetlands relative tocurrent conditionsAction 1 –Implement all aspects of Lakeville’s NPDES Phase II MS4 permit SWPPPAction 2 – Require development to comply with the conditions and policies of the City’sNondegradation Report and SWPPPAction 3 – Require development to comply with and follow all BMPs for erosion andsedimentation control as specified in the MPCA publication "Protecting Water Quality inUrban Areas" as may be amendedLakeville Water Resources Management Plan Page 2-1

Action 4 – Require compliance with City's Erosion and Sediment Control ordinance(Section 10-4-5)Action 5 – Encourage implementation of BMPs beyond the minimum requiredAction 6 – Continue to implement buffer requirements of the Lakeville WetlandManagement Plan and the South Creek Management PlanAction 7 – Adopt ordinances implementing the VRWJPO buffer standards for streams andwater coursesAction 8 – Work with the MPCA and other agencies to develop and implement TotalMaximum Daily Load (TMDL) studies on all impaired water bodies, including, but notlimited to those included on the 303(d) listAction 9 – Actively participate in the TMDL process including but not limited to studysponsorship, participation in public meetings, education, liaison activities, and assistance inseeking and providing fundingAction 10 – Determine appropriate responsibilities in implementing load reductionmeasures identified in TMDL studiesAction 11 – Update water quality modeling of major subwatersheds and diagnose potentialproblemsAction 12 – Continue with an aggressive program of street sweeping and vacuum cleaningof settlement devices and manholesAction 13 – Continue program of water quality education aimed at lake associations, civicgroups, schools, and other community groupsOBJECTIVE 2 – Continue and improve the water quality monitoring program for the city ofLakevilleAction 1 – Maintain and enhance water quality monitoring in the cityAction 2 – Collect, organize, and interpret water quality monitoring dataAction 3 – Make water quality monitoring data available via website or other means andsummarize data for public information purposesOBJECTIVE 3 – Continue management programs for Orchard, Lee, Kingsley, Valley andMarion LakesAction 1 –Prepare or update management plans toward meeting water quality goals forpriority lakes and their watersheds including Orchard, Lee, Kingsley, Valley and MarionLakesLakeville Water Resources Management Plan Page 2-2

Action 2 – Collaborate with the VRWJPO, the BDWMO, Soil and Water ConservationDistricts (SWCD), federal, state, and other programs to cost share for lake shore restorationprojects undertaken by landownersAction 3 – Collaborate with other agencies to monitor lakes, including participation incitizen volunteer monitoring efforts such as Citizen Assisted Monitoring Program (CAMP)OBJECTIVE 4 – Minimize water quality impacts (including thermal impacts) from landdisturbingactivities, including new development and redevelopment (urban/rural), roadconstruction, and rural usesAction 1 – Require development to comply with and follow all BMPs for erosion andsedimentation control as specified in the MPCA publication "Protecting Water Quality inUrban Areas" as may be amendedAction 2 – Require compliance with City's stormwater design requirements and Erosionand Sediment Control ordinanceAction 3 – Require development to comply with the conditions and policies of the City’sNondegradation Report and SWPPPAction 4 – Require compliance with the BDWMO and VRWJPO Stormwater ManagementStandards, Construction Erosion Control, Post Construction Water Quality Criteria, andRunoff Temperature Control Criteria (See Appendix F)Action 5 – Require that temporary and permanent stormwater basins incorporaterecommendations from the Nationwide Urban Runoff Program (NURP)Action 6 – Continue to implement buffer requirements of the Lakeville WetlandManagement Plan and the South Creek Management PlanAction 7 – Adopt ordinances implementing the VRWJPO buffer standards for streams andwater coursesAction 8 – Encourage implementation of BMPs beyond the minimum requiredAction 9 – Monitor emerging technologies for protecting the cold-water fishery, includingreducing thermal impacts to streams from stormwater runoffOBJECTIVE 5 – Ensure stormwater management systems are maintained while minimizingthe total cost of the stormwater system (construction plus maintenance)Action 1 – Use higher-level hydrograph models with variety of storm durations andrecurrence intervals to optimize designAction 2 – Emphasize development of stormwater storage to keep peak rates at or belowexisting rates of runoffLakeville Water Resources Management Plan Page 2-3

Action 3 – Construct regional basins to maximum extent possible to minimize cost of basinmaintenanceAction 4 – Establish and implement stormwater management system maintenancestandardsAction 5 –Implement all aspects of Lakeville’s NPDES Phase II MS4 permit SWPPPAction 6 – Continue inspection program for identification of maintenance problems andillicit discharge detectionOBJECTIVE 6 – Continue to meet or exceed all water-related regulations that apply aspromulgated by the federal government, the State of Minnesota, Dakota County, theVermillion River Watershed Joint Powers Organization, the Black Dog WatershedManagement Organization, and the Metropolitan CouncilAction 1 – Involve appropriate agencies in the development of this planAction 2 – Adopt and implement this planAction 3 – Update City ordinances where necessary to meet current requirements of theFederal Government, the State of Minnesota, Dakota County, the Vermillion RiverWatershed Joint Powers Organization, the Black Dog Watershed Management Organization,and the Metropolitan CouncilAction 4 –Implement all aspects of Lakeville’s NPDES Phase II MS4 permit SWPPPAction 5 – Work with the MPCA and other agencies to develop and implement TotalMaximum Daily Load (TMDL) studies on all impaired water bodies, including, but notlimited to those included on the 303(d) listAction 6 – Track contaminant load reduction achieved by implemented BMPs2.3 WATER QUANTITYGoalManage the rate and volume of runoff entering rivers, streams, lakes, and wetlandswithin the city of Lakeville2.3.1 A reduction in runoff volumes will be supported and promoted.Policies2.3.2 Use of existing natural retention and detention areas for stormwatermanagement to minimize flow rates will be encouraged.2.3.3 The City will continue implementation of the South Creek Management Plan.Lakeville Water Resources Management Plan Page 2-4

2.3.4 Stormwater will be managed to minimize erosion.Policies2.3.5 Outlets from landlocked basins will be allowed, only when such outlets areconsistent with State and federal regulations, and the downstream impacts, riparianimpacts, and habitat impacts of such outlets have been analyzed and no detrimentalimpacts result.2.3.6 The Orchard Lake outlet will continue to restrict peak outflow to no more than65 c.f.s. for the 100 year, 24 hour runoff event, per BDWMO requirement.Surface Water Quantity ObjectivesOBJECTIVE 1 – Minimize downstream impacts of runoff from land-disturbing activitiesincluding new development and redevelopment, road construction, and rural usesAction 1 – Plan for and design storage basins to accommodate runoff from fully developedwatershed without increase in flow rates at watershed outletsAction 2 – Meet BDWMO and VRWJPO requirements for discharge limitationsAction 3 – Require compliance with City's stormwater design requirements and Erosionand Sediment Control ordinanceAction 4 – Require compliance with the BDWMO and VRWJPO Stormwater ManagementStandards, Construction Erosion Control, Post Construction Water Quality Criteria, andRunoff Temperature Control Criteria (See Appendix F)Action 5 – Continue to implement the South Creek Management PlanAction 6 – Provide funding for staff time or contracted services to provide oversight andguidance in review of developer’s design and plans for onsite water management practices tomeet City of Lakeville standardsAction 7 – Implement via ordinance and enforcement the City’s Nondegradation Planstandard for 0.5 inches of infiltration for new and re-development projects, whereappropriate, in all districts outside of the South Creek DistrictAction 8 – Enforce the requirement of 1.5 inches of infiltration for development projectswithin the South Creek District as per the South Creek Management PlanOBJECTIVE 2 – Assist in mitigating and reducing the impact of past increases in stormwaterdischarge on downstream conveyance systemsAction 1 – Continue to identify stream corridor reaches for streambank erosion reductionprojects, and restore damaged stream banks at priority locations, taking advantage ofpartnerships and cost-sharing whenever possibleLakeville Water Resources Management Plan Page 2-5

Action 2 – Collaborate with Soil and Water Conservation Districts (SWCD), federal, state,and local programs to cost share for streambank restoration projects undertaken bylandownersAction 3 – Seek opportunities to retrofit existing developments with low-impactdevelopment techniques, in partnership with other units of governmentAction 4 – Seek opportunities to retrofit sites under re-development with low-impactdevelopment techniquesAction 5 – Implement via ordinance and enforcement the City’s Nondegradation Planstandard for 0.5 inches of infiltration for new and re-development projects, whereappropriate, in all districts outside of the South Creek DistrictAction 6 – Enforce the requirement of 1.5 inches of infiltration for development projectswithin the South Creek District as per the South Creek Management PlanOBJECTIVE 3 – Address gully erosion problems in the city of LakevilleAction – Work cooperatively with other government entities to address identified gullyerosion problems in the city2.4 GROUNDWATERGoalPoliciesProtect groundwater quality and quantity to preserve it for sustainable andbeneficial purposes2.4.1 Groundwater quality should not be sacrificed to manage surface water. Holdingponds, wetlands and other water storage areas must be designed to protectgroundwater.2.4.2 Infiltration of stormwater and resulting groundwater recharge will be promotedwhere it is feasible and does not pose a threat to groundwater quality.Groundwater ObjectivesOBJECTIVE 1 – Protect groundwater quality and quantityAction 1 – Continue implementation of the City of Lakeville Wellhead Protection PlanAction 2 – Continue using the Lakeville Well Siting Study to protect vulnerable areas frominappropriate land usesAction 3 – Work with Dakota County Health Department in ensuring that abandoned wellsare properly sealed according to the Minnesota Department of Health Well CodeLakeville Water Resources Management Plan Page 2-6

Action 4 – Continue to monitor Vermillion River tributaries for temperature and flow rateAction 5 – Identify vulnerable wellhead protection areas within the city and define themeasures that will reduce the threat to drinking water to the maximum extent practicable. Thesemeasures will be developed in accordance with the Minnesota Department of Health’sEvaluating Proposed Storm Water Infiltration Projects in Vulnerable Wellhead ProtectionAreas, and the MPCA’s Minnesota Stormwater Manual guidance for potential stormwaterhotspots.Action 6 – Continue to update and implement the City of Lakeville Water ConservationPlan.OBJECTIVE 2 – Avoid reductions in the base flow of the River and its tributaries, andreductions in “normal” water levels of lakes and wetlands, due to increased appropriationsAction 1 – Continue using the Lakeville Well Siting Study to maximize groundwatersustainabilityAction 2 – Avoid watershed diversion to sustain water levels in other watersheds andsurface waterOBJECTIVE 3 – Eliminate discharges of fecal coliform bacteria and minimize discharges ofnitrate and other pollutants to groundwater and surface waters of the city of LakevilleAction 1 – Cooperate with the county’s efforts to inventory failing and non-compliant septicsystems and jointly prioritize areas for septic system upgradesAction 2 – Use Dakota County Well Management database in plan and permit reviews, andprovide educationOBJECTIVE 4 – Support and assist in groundwater research, regulation, and educationAction 1 – Collaborate with State and local agencies to provide groundwater and streammonitoring data for use in research and to develop targeted educational messagesAction 2 – Cooperate with the Minnesota Department of Health (MDH), Dakota County andother agencies to periodically assess the vulnerability of groundwater used for drinking watersuppliesLakeville Water Resources Management Plan Page 2-7

2.5 WETLANDS AND HABITATGoalsMaintain and enhance, where possible, the functions and values of existing wetlandsand habitats within the city.Promote the restoration and/or creation of wetlands.2.5.1 The City of Lakeville will work to achieve no net loss of wetland quantity,quality, and biological diversity.2.5.2 Wetland replacements will provide equal or greater functions and values at thereplacement ratio dictated by the Lakeville Wetland Management Plan.2.5.3 Avoidance of direct or indirect wetland disturbance will be required for alldevelopments and land-disturbing activities, in accordance with state and federalrequirements and the Lakeville Wetland Management Plan.2.5.4 Buffers, acting as filter strips, will be required around every wetland based onthe Lakeville Wetland Management Plan.Policies2.5.5 Wetlands will be protected from chemical, physical, biological, or hydrologicalchanges so as to prevent significant adverse impacts to the following designatedwetland uses: maintaining biological diversity, preserving wildlife habitat, providingrecreational opportunities, erosion control, groundwater recharge, low flowaugmentation, stormwater retention, stream sedimentation, and aesthetic enjoyment,as specified in Minnesota Rules 7050.2.5.6 Fragmentation of natural areas and corridors will be avoided when feasible.2.5.7 Impacts to locally and regionally significant natural areas will be avoided whenfeasible or mitigated when possible.2.5.8 High priority natural areas identified through the land cover mapping done forthe Dakota County Farmland & Natural Area Program, the Dakota County BiologicalSurvey and other inventories will be used to assist in evaluating developmentproposals.Wetlands and Habitat ObjectivesOBJECTIVE 1 – Protect existing wetlands and fish and wildlife habitat areas and promote thedevelopment of additional habitat areasAction 1 – Act as the Local Governmental Unit enforcing the Minnesota WetlandsConservation ActAction 2 – Inform potential developers of the MDNR protected waters and Corps Section404 permit programsLakeville Water Resources Management Plan Page 2-8

Action 3 – Continue implementation of the Lakeville Wetland Management PlanAction 4 – Continue implementation of the South Creek Management PlanAction 5 – Collaborate with other agencies and organizations to develop or enhance wildlifehabitat corridors that connect open space, stream corridors, lake buffers, wetland buffersand stormwater management facilitiesAction 6 – Collaborate with conservation agencies and other organizations to supplementtheir fish and wildlife habitat protection and enhancement efforts and programsOBJECTIVE 2 – Identify and pursue wetland restoration opportunities within the city ofLakevilleAction – Identify priority wetland restoration project opportunitiesOBJECTIVE 3 – Protect sensitive habitats and communities, and rare speciesAction 1 – Cooperate with Dakota County and the Dakota County Soil and WaterConservation District to identify, rank, and map disturbed shoreline areas at lakes andstreamsAction 2 – Review projects and plans with an awareness of sensitive habitats andcommunities, and rare speciesOBJECTIVE 4 – Assist in public education efforts regarding the fish and wildlife in the cityAction 1 – Assist the BDWMO, the VRWJPO, and other agencies with development anddistribution of educational materials or support programs that provide information on thefish and wildlife resources of the city of LakevilleAction 2 – Continue participation in the Wetland Health Evaluation Program (WHEP)Lakeville Water Resources Management Plan Page 2-9

2.6 FLOODPLAINSGoalManage and protect the floodplains of the city from encroachment.2.6.1 The natural function of the floodplain as a floodwater storage area should beprotected from encroachment.2.6.2 The City will work to maintain no net loss of floodplain storage.2.6.3 Floodplains will be managed to maintain critical 100-year flood storagevolumes.Policies2.6.4 The City will work to restrict construction of new structures to sites above theregulatory flood protection elevation.2.6.5 Floodplain zoning regulations will be consistent with Dakota County waterresource plans and ordinances.2.6.6 Upstream floodwater storage should be maximized.2.6.7 Accumulated sediment should be removed from flood storage facilities prior toreaching 50 percent of the storage area’s capacity.2.6.8 Infiltration in appropriate floodplain areas should be increased throughincreased vegetated areas and reduced impervious surfaces.Floodplain ObjectivesOBJECTIVE 1 – Reduce flood damage to homes and businesses as much as practicalAction 1 – Prepare preliminary designs to avoid flooding of homes adjacent to water bodiesfor events up to 100-year stormsAction 2 – Prepare preliminary design for subtrunks for the 10-year stormAction 3 – Design drainage facilities adjacent to arterial roads and highways and majorcollector streets to convey the 100-year stormAction 4 – Allow local streets and parking areas to overtop no more than one foot in the100-year stormAction 5 – Where existing housing has the identified potential for flood damage, proposeredesign of storm drainage system to eliminate flooding in the 100-year stormAction 6 – Minimize uncertainties and flood damage adjacent to landlocked ponds byplanning for some form of outletLakeville Water Resources Management Plan Page 2-10

OBJECTIVE 2 – Identify and protect floodplainsAction 1 – Continue participation in the National Flood Insurance ProgramAction 2 – Cooperate and coordinate with the Dakota County’s FEMA floodplain mappingupdates as neededAction 3 – Obtain flood and drainage easements and easements for maintenance access andover emergency overflow routes during development and/or building permit processesAction 4 –Assist the BDWMO, the VRWJPO, and other agencies with development anddistribution of educational materials or support programs that provide informationregarding floodplain locations, protection, and floodplain land use and land alterationrestrictionsOBJECTIVE 3 – Limit floodplain alterations in order to obtain "no net loss" of floodplainstorage, and including the preservation, restoration and management of floodplain wetlandsAction 1 – Require compensatory storage for filling or structures within the floodplainAction 2 – Continue implementation of the Lakeville Wetland Management PlanAction 3 – Continue implementation of the South Creek Management PlanOBJECTIVE 4 – Adopt shoreland and floodplain ordinances that are compatible with existingcounty and state ordinances, VRWJPO, and BDWMO standardsAction 1 – Review the status of Lakeville floodplain and shoreland ordinancesAction 2 – Make changes to ordinances as needed2.7 OPEN SPACE AND RECREATIONAL AREASGoalPoliciesDevelop or improve recreational, fish and wildlife, and open space areas andaccessibility in conjunction with water quality improvement projects2.7.1 Recreational uses of waterbodies that are a threat to human health will not bepromoted by the City of Lakeville.2.7.2 Impacts to regionally and locally important natural areas should be avoided ormitigated.2.7.3 Fragmenting natural areas and natural/wildlife corridors should be avoided orminimized.Lakeville Water Resources Management Plan Page 2-11

2.7.4 Creation and preservation of navigational and wading access to public waterswill be sought, where appropriate.2.7.5 Natural areas, shoreland and wetland environments will be preserved, restoredand enhanced wherever possible.Policies2.7.6 Use of native vegetation should be considered for local government projects andprivate development open spaces.2.7.7 Existing open spaces, outdoor recreational amenities, and cultural resources willbe connected and enhanced whenever possible.2.7.8 Open space uses in wellhead protection areas will be encouraged and promoted.2.7.9 Efforts to create a continuous trail system along the Vermillion River and itsmajor tributaries will be supported.Open Space and Recreational Areas ObjectivesOBJECTIVE 1 – Enhance open space and recreational opportunities in conjunction with waterquality improvementsAction 1 – Consider the above Policies 2.7.1 - 2.7.9 when reviewing development proposalsAction 2 – Review and revise City ordinances if needed for consistency with the abovePolicies 2.7.1 - 2.7.9OBJECTIVE 2 – Maintain natural stream corridor and lake shoreline qualities for recreationalusers and local residents.Action 1 – Collaborate with agency, non-profit, and volunteer groups for river cleanupactivitiesAction 2 – Adopt shoreland and floodplain ordinances that are compatible with existingcounty and state ordinances, and VRWJPO and BDWMO standardsOBJECTIVE 3 – Partner with others to develop a plan to improve access to public waters,while avoiding impacts of over-use or conflicting usesAction – Participate in VRWJPO activities regarding river corridor access issuesLakeville Water Resources Management Plan Page 2-12

2.8 LAND USE MANAGEMENTGoalProtect and conserve water resources by promoting sustainable growth, integratedland use and land use planning, and water resource management2.8.1 The presence of environmentally sensitive natural resource areas should guideland use management decisions.Policies2.8.2 The impacts of land disturbing activities on water resources, includingcumulative impacts, should be considered for each proposed activity before the activityoccurs.2.8.3 Stormwater best management practices (BMPs) must be identified as part of thedevelopment approval process.Land Use Management ObjectivesOBJECTIVE 1 – Require land disturbing activities including new development andredevelopment, road construction and other uses within the city of Lakeville to addressimpacts on water resources, including cumulative impactsAction 1 – Require development plans to consider impacts on local natural resources andcorresponding receiving watersAction 2 – Develop criteria to consider potential off-site impacts2.9 EDUCATIONGoalOffer programs, educational opportunities and information that facilitate anunderstanding of water resource issues in the city of Lakeville and downstreamPolicy2.9.1 The City of Lakeville will provide support where appropriate, for thedevelopment and distribution of educational materials and assist other agenciesefforts.Education ObjectivesOBJECTIVE 1 – Develop information and data for educational and other purposesAction 1 – Continue the existing Lakeville water monitoring programAction 2 – Collaborate with other agencies toward expanding and improving the dataavailableLakeville Water Resources Management Plan Page 2-13

OBJECTIVE 2 – Provide opportunities for community involvement and access to informationAction 1 – Continue to support and facilitate existing volunteer programs in Lakevilleincluding the Adopt-A-Pond program, the Citizen Assisted Monitoring Program (CAMP), theWetland Health Evaluation Project (WHEP), the School of Environmental Studies Lake ProfileProject, and the Vermillion River Watch programAction 2 – Seek new opportunities for collaboration with volunteer groupsAction 3 – Continue to distribute information through presentations, written materials,Lakeville’s local access TV channel 16, and via the Lakeville web site athttp://www.ci.lakeville.mn.usAction 4 – Develop educational materials that target public awareness of buffer desirabilityand requirements and the dangers and regulations regarding illicit discharge to storm sewersLakeville Water Resources Management Plan Page 2-14

Section 3.0 Lakeville Physical Environment3.1 LAND USELand use describes the type of development on a piece of land or the function it serves. This includesnatural as well as developed areas. Land use for each parcel in the city of Lakeville (updated in2006) is presented in Figure 3.1.1 and summarized by land use type in the figure below.Land use in Lakeville is primarily residential, with single family residences occupying over 30percent of the city. Most of the residential areas are concentrated in the north part of the city or tothe south and east of Lake Marion. Commercial areas are concentrated along I-35, as well as at theintersection of County Road 23 (Cedar Ave.) and County Road 9 (Dodd Blvd.) and the intersection ofCounty Road 50 (Kenwood Trail) and County Road 9 (Dodd Blvd.). Approximately 3 percent of thecity is classified as industrial land use; the majority of this area, including the Airlake IndustrialPark, is located in the southeast corner of the city along County Road 70 (215 th Street W).Agricultural use accounts for one-quarter of the land in the city of Lakeville. Most of this area islocated in the Farmington Outlet Stormwater District in the east-central part of the city betweenCounty Road 9 (Dodd Blvd.) and County Road 23 (Cedar Ave.). Additional agricultural land use islocated in the southwest and northeast corners of the city.2006 Lakeville Land UseWater9.3%Agricultural25.7%Single FamilyResidential31.5%Airport0.2%Commercial3.0%Rural Residential2.0%Multiple FamilyResidential3.3%Industrial3.4%Institutional3.7%Grassland6.2%Forest10.1%Highway1.4%Summary of city of Lakeville 2006 land use from Figure 3.1.1Lakeville Water Resources Management Plan Page 3-1

Figures 3.1.2 and 3.1.3 show the anticipated future land use in the city for 2020 and 2030,respectively. The 2020 projection data is summarized in the inset figure below. Expected changes inland use include a large increase in residential areas (from 37 percent to 56 percent) and more thandoubling of commercial areas (from 3 percent to 6.5 percent). Additional new development ofresidential areas is anticipated in the southeast part of the city in the Farmington Outlet StormwaterDistrict and South Creek Stormwater District. Some of this area is designated for inclusion in theMetropolitan Urban Service Areas (MUSA) as of 2010.2020 Lakeville Land UseWater9.3%Airport0.2%Agricultural5.9% Commercial6.5%Forest6.0%Single FamilyResidential39.3%Grassland6.4%Industrial4.6%Highway1.4%Institutional4.0%Multiple FamilyResidentialRural Residential10.4%6.1%Summary of city of Lakeville 2020 land use from Figure 3.1.23.2 CLIMATE AND PRECIPITATIONBecause of its location near the center of the North American continent, Lakeville—along with therest of Minnesota—has a continental climate, meaning it experiences a wide variation in climateconditions (e.g., droughts and floods, heat and cold).The mean annual temperature for Lakeville is 45°F, as measured at the Minneapolis/ St. Paul (MSP)airport station (1971-2000). Mean monthly temperatures vary from 13.1°F in January to 73.2°F inJuly (1971-2000). Extreme temperatures recorded were a high of 108°F on July 14, 1936 and a lowof -34°F on January 1, 1936 and January 19, 1970. For the period 1948-1992, the average date forlatest occurrence of freezing temperatures is April 29, while the average date for the first autumnfrost is October 6. The average frost-free period (growing season) is approximately 160 days.Lakeville Water Resources Management Plan Page 3-2

Table 3.2.1 summarizes precipitation data for the MSP airport station. Average total annualprecipitation (1971-2000) is 29.4 inches at the MSP airport station and has ranged from a low of 11.5inches in 1910, to a high of 40.2 inches in 1911. The mean monthly precipitation (1971-2000) variesfrom 4.3 inches in June to 0.8 inches in January. From May to September, the growing seasonmonths, the average rainfall (1971-2000) is 18.4 inches at MSP or about 62 percent of the averageannual precipitation. Average annual lake evaporation is about 31 inches.Average annual snowfall (1971-2000) is 56 inches at the MSP airport station. Extreme snowfallrecords range from 98.6 inches during the 1983-1984 season to 14.2 inches at MSP during the1930-1931 season.Average weather imposes little strain on the typical stormwater drainage system. Extremes ofprecipitation and snowmelt are important for design of flood control systems. The National WeatherService has data on extreme precipitation events that can be used to aid in the design of flood controlsystems. The amount, rate, and type of precipitation are important in determining flood levels andstormwater runoff rates, all of which impact water resources. In urbanized watersheds, shorterduration events tend to play a larger role in predicting high water levels on basins. Shorter-durationevents are generally used by hydrologists to study local issues (sizing catch basins, storm sewerpipes, etc.) Longer-duration events are generally used by hydrologists to study regional issues, suchas predicting high water levels for regional basins and basins that have no outlets (landlocked), orthat have small outlets relative to their watershed size.Snowmelt and rainstorms that occur with earlyspring snowmelt are significant in this region. Thevolumes of runoff generated, although they occurover a long period, can have significant impactswhere the contributing drainage area to a lake orpond is large and the outlet is small (or there is nooutlet). Extremes of snowmelt most often affectmajor rivers, the design of large stormwater storageLakeville Climate & Precipitation FactsMean annual temperatureAverage annual precipitationAverage annual snowfallAverage annual lakeevaporationareas, and landlocked basins, while extremes of precipitation most often affect the design ofconveyance facilities.45 F29.4 inches56 inches31 inchesIn contrast with stormwater drainage facilities, stormwater quality treatment systems are designedbased on smaller, more frequent storms. These more frequent storms account for the majority of theannual pollutant loadings from urban watersheds. Analysis of rainfall data (1971-2000) from theMSP station found that 90 percent of the storms produced 1.05 inches or less of rainfall (MNStormwater Manual, 2005).The major sources of information regarding rainfall in the region are publications TP-40 and TP-49issued by the National Weather Bureau (now the National Weather Service) in 1961 and 1964,respectively. These data are generally consistent with the specific analysis of Minneapolis-St. Paulintensity-frequency data compiled by Yarnell (USDA Miscellaneous Publication 204). The sourcesLakeville Water Resources Management Plan Page 3-3

give information on storm durations of up to 10 days. Runoff from spring snowmelt is alsoimportant in this region, and the Soil Conservation Service’s National Engineering Handbook,Hydrology, Section 4, presents maps of regional runoff volume. The information from all of thesesources (except for the Yarnell analysis) is summarized in the Hydrology Guide for Minnesota,published by the USDA’s Soil Conservation Service. Table 3.2.2 lists many of the precipitation andrunoff events used for design purposes.Even with wide variations in climate conditions, climatologists have found four significant climatetrends in the Upper Midwest (see right).According to the Soil and Water ConservationSociety’s (SWCS) 2003 report on climate change,total precipitation amounts in the United States(and in the Great Lakes region) are trendingupward, as are storm intensities. Precipitationrecords in the Twin Cities area show the annualaverage precipitation has increased, as shown in thefollowing examples:Upper Midwest Climate Trends1. Warmer winters2. Higher minimum temperatures3. Higher dew points4. Changes in precipitation trends(more rainfall from heavy thunderstormevents; increased snowfall)Source: Minnesota Weather Almanac, Seeley, 2006.Minneapolis-St. Paul Airport station – theaverage annual precipitation has increased from 28.32 inches (1961-1990 average) to 29.41inches (1971-2000 average), a 3.8% increase (data from the Climatology Working Groupwebsite: http://climate.umn.edu/). St. Paul station – the average annual precipitation has increased from 30.30 inches (1961-1990 average, from the MN DNR State Climatology Office) to 32.59 inches (1971-2000average), a 7.6% increase (data from the Midwestern Regional Climate Center websitehttp://mcc.sws.uiuc.edu/climate_midwest/mwclimate_data_summaries.htm#).As noted by the SWCS, increased storm intensities result in increased soil erosion and increasedrunoff. The MPCA’s global warming website (http://www.pca.state.mn.us/hot/globalwarming.html)states that increased flooding could also result from more intense precipitation events.Climate information can be obtained from a number of sources, such as the following websites:For climate information about the Twin Cities metropolitan area:http://climate.umn.edu/doc/twin_cities/twin_cities.htmFor a wide range of Minnesota climate information:http://climate.umn.edu/For other Minnesota climate information:http://www.dnr.state.mn.us/climate/index.htmlLakeville Water Resources Management Plan Page 3-4

Table 3.2.1. Precipitation Summary—Minneapolis/St. Paul Airport StationAverages: 1971-2000 Extremes: 1891-2001Total Precipitation, Inches Snow, inches # Days with PrecipMonth Mean High—Yr Low—Yr 1-Day Max Mean High—Yr > .10 > .50 > 1.0Jan 1.04 3.63 1967 0.05 1892 1.21 1/24/1967 13.7 46.4 1982 3.6 0.3 0.0Feb 0.79 3.25 1922 0.03 1894 1.90 2/4/1930 8.2 26.5 1962 2.7 0.3 0.0Mar 1.86 4.75 1965 0.09 1910 1.62 3/1/1965 10.5 46.1 1965 5.1 0.8 0.2Apr 2.31 7.00 2001 0.16 1987 2.22 4/27/1975 3.1 21.8 1983 5.5 1.4 0.2May 3.24 10.33 1906 0.21 1934 3.16 5/21/1906 0.1 2.4 1954 7.2 2.2 0.7Jun 4.34 9.82 1990 0.22 1988 2.91 6/7/1984 0.0 0.0 1949 7.5 3.0 1.1Jul 4.04 17.90 1987 0.11 1936 9.15 7/23/1987 0.0 0.0 1948 6.2 2.4 0.9Aug 4.05 9.31 1977 0.20 1925 7.28 8/30/1977 0.0 0.0 1948 6.5 2.6 0.9Sep 2.69 7.77 1903 0.41 1940 4.96 9/12/1903 0.0 0.4 1985 5.6 1.7 0.6Oct 2.11 6.42 1911 0.01 1952 2.75 10/19/1934 0.6 8.2 1991 4.4 1.3 0.4Nov 1.94 5.29 1991 0.02 1939 2.52 11/11/1940 10.0 46.9 1991 4.5 1.1 0.2Dec 1.00 4.27 1982 0.00 1943 1.50 12/14/1891 10.2 33.5 1969 2.9 0.2 0.1Annual 29.41 40.15 1911 11.54 1910 9.15 7/23/1987 56.3 101.5 1983 61.8 17.1 5.3Winter 2.83 6.24 1967 0.69 1958 1.90 2/24/1930 32.1 71.7 1967 9.3 0.8 0.2Spring 7.41 16.13 1965 2.12 1910 3.16 5/21/1906 13.7 48.1 1965 17.8 4.3 1.0Summer 12.43 23.52 1987 1.73 1894 9.15 7/23/1987 0.0 0.0 1949 20.2 8.0 3.2Fall 6.74 13.50 1911 1.71 1952 4.96 9/12/1903 10.6 55.1 1991 14.5 4.0 1.3Source: Midwest Regional Climate Center Website (http://www.mcc.sws.uiuc.edu)Lakeville Water Resources Management Plan Page 3-5

Table 3.2.2. Selected Precipitation and Runoff EventsType and FrequencyRainfallDurationAmount(Inches)10-year 24 hour4.225-year 4.850-year 5.3100-year6.025 year 10 day8.850-year 10.0100-yearRunoff (snowmelt)11.010-year 10 day4.725-year 5.750-year 6.4100-yearSource: Hydrology Guide for Minnesota (USDA Soil Conservation Service)7.13.3 TOPOGRAPHYThe city’s topography is a result of its glacial history and is presented in Figure 3.3.1. The mostrecent glaciation took place about 12,000 years ago (the Pleistocene era). As the glaciers movedacross the land, they cut and moved large amounts of material, sometimes carrying it for longdistances. As the glaciers retreated, this material (called glacial drift) was left behind and reworkedby the resulting glacial meltwater. Two geologic features/landforms occupy the majority of the cityof Lakeville: 1) glacial moraine; and 2) outwash plain.Glacial moraines (termination points of a glacial advance) cover large areas in the north and west ofthe city of Lakeville. This landform, also called knob and kettle topography, is characterized byrolling to hilly terrain interspersed with poorly drained depressions that form many deep ponds andlakes.Areas of outwash plain extend from northwest to southeast across the city of Lakeville. Outwashplains were created as water from the melting glaciers reworked the debris carried by the glaciers.Outwash plains contain some of the richest gravel deposits in the metropolitan area.Upland terrain located in the center of the city is separated from the highlands in the southwest by alow-lying area which includes Lake Marion and drains to the southeast into South Creek andLakeville Water Resources Management Plan Page 3-6

eventually the Vermillion River. Fewer ponds are observed in the south and the east than in thenorthwest part of the city. In these outwash regions, elevations decrease steadily as the land drainsinto streams that flow towards the Vermillion River. The ravines surrounding these tributarychannels are generally less steep than that observed in the glacial moraine located in the northwestpart of the city. The flattest areas are those immediately surrounding the downstream reaches ofSouth Creek and North Creek before they exit the city.Land surface elevations in the city of Lakeville range from a high value of 1189 feet mean sea level(MSL) in the southwest corner of the city, to a low value of 907 feet in the northeast area of the city.The average elevation is 1012.7 ft MSL.Dakota County has 2-foot contour interval topographic mapping available for the entire county.There are also 10-foot contour interval topographic maps available from the U.S. Geological Survey.The city of Lakeville is divided into six stormwater districts (see Figure 3.4.1) which fall into twomajor watersheds: the Vermillion River watershed and the Black Dog watershed. The Black Dogwatershed drains to the Minnesota River, while the Vermillion River discharges into the MississippiRiver near Hastings, Minnesota. A watershed divide runs southwest from the boundary betweenBurnsville and Lakeville, across the high terrain located in the center of the city, then extends westbetween Orchard Lake and Lake Marion to the western boundary of Lakeville. This divide placesabout 16% of the city within the Black Dog watershed (and therefore the greater Minnesota Riverwatershed). This area includes the Orchard Lake Stormwater District and Crystal Lake StormwaterDistrict.The remaining 84% of the city area drains east to the Vermillion River which, in turn, drains to theMississippi River. The Vermillion River watershed is further divided into four sub-watershedswithin the city of Lakeville. The North Creek Stormwater District drains west along the north side ofthe city. The Farmington Outlet Stormwater District lies to the south of the North Creek StormwaterDistrict and drains east from the elevated terrain near the center of Lakeville. The Lake MarionStormwater District exists to the west of the Farmington Outlet Stormwater District and drainssoutheast to Lake Marion, which in turn drains into the South Creek Stormwater District and to theVermillion River.Lakeville Water Resources Management Plan Page 3-7

3.4.1 Orchard Lake Stormwater DistrictThe Orchard Lake District encompasses approximately 2,511 acres.The southerly border is located approximately at 185 th Street Westand extends north to the boundary with the City of Burnsville, andwest from approximately one-half mile west of Ipava Avenue to theboundary with Credit River Township. Drainage from the OrchardLake District flows into Credit River, which discharges to theMinnesota River. The District is within the Black Dog WatershedManagement Organization (BDWMO) jurisdiction. Kingsley andOrchard are the major lakes in the district and lie entirely withinthe boundaries of the city of Lakeville. Two smaller lakes,Horseshoe and Goose Lakes, are also located in this district.Horseshoe Lake is located on the boundary with the city ofBurnsville, and outflow drains north.City of LakevilleStormwater DistrictsOrchard LakeCrystal LakeNorth CreekFarmington OutletLake MarionSouth CreekThe boundaries of the Lakeville Stormwater Districts are shown on Figure 3.4.1. More detailon the drainage system is contained in Section 4 of this plan.Within the city of Lakeville, an area of approximately 2,087 acres is tributary to Orchard Lake,the largest surface water feature in the district. The outlet from the lake is to the west into CreditRiver Township through Murphy Hanrehan Park Reserve. Part of Credit River Township(roughly 173 acres) is also tributary to Orchard Lake and runoff from this area flows throughLakeville in the southwestern portion of the watershed.Approximately 424 acres analyzed as part of this district do not drain to Orchard Lake, but northand west to other municipalities. Runoff from approximately 200 acres within this district flowsnorth into the city of Burnsville. Runoff from approximately 224 acres within the district flowswest into the Credit River Township.The land south of Orchard Lake is developed with medium density residential areas.Commercial and medium density residential areas occupy the Orchard Lake District east of I-35.The area to the north of Orchard Lake and between Orchard Lake and I-35 is less developed,containing some medium- to low-density residential and forest areas. The landforms in thenorthwestern part of Lakeville are nearly level to very steep and are comprised of unconsolidatedclay, sand, and gravel deposited as glacial moraines.3.4.2 Crystal Lake Stormwater DistrictThe Crystal Lake District has an area of approximately 1,420 acres in the city of Lakeville alongthe northern boundary of the city. It extends from Kenwood Trail on the west to HighviewAvenue on the east, between 175 th Street and the boundary with the city of Burnsville. Themajority of Crystal Lake and its watershed lie within the city of Burnsville and within the BlackDog Watershed Management Organization, of which Lakeville is a member. Outflow fromCrystal Lake flows to the Minnesota River via Earley Lake and Sunset Pond.Lakeville Water Resources Management Plan Page 3-8

The boundaries of the Lakeville Stormwater Districts are shown on Figure 3.4.1. More detailon the drainage system is contained in Section 4 of this plan.This entire district is tributary to Crystal Lake, although approximately 285 acres within thedistrict flow into Lee Lake. A gated outlet directs outflow from large events from Lee Lake to theeast under I-35. Runoff from the western Crystal Lake District flows to Crystal Lake by twomeans: a pond in Oak Shores Park (north of 162 nd Street West, between Jamaica Avenue andJoplin Avenue) and a drainage swale in Oak Shores Park (just east of Jamaica Avenue, between161 st Street West and Oak Shore Drive). Since 1993, runoff from the eastern portion of thedistrict has been routed along County Road 46 to the Bluebill Bay Pond as part of thereconstruction of County Road 46. The ponding basin in Bluebill Bay Estates is located south ofBluebill Bay Road and west of Inglewood Drive. Runoff from approximately 138 acres in theBuck Hill development in the city of Burnsville flows through the city of Lakeville Crystal LakeDistrict watershed into Crystal Lake.Within the city of Lakeville, most of the Crystal Lake District is developed. The majority of thearea is occupied by single family homes. Commercial and industrial are present surrounding I-35. Some park and grassland areas are also present.3.4.3 North Creek Stormwater DistrictThe total area of the North Creek watershed at the Lakeville-Farmington border is approximately12,200 acres, 5,737 of which lie within the city of Lakeville. Of the remaining area, 297 acres liewithin the city of Farmington and 6,150 acres lie within the city of Apple Valley. The District islocated in the portion of the city of Lakeville lying generally north of 180 th Street.The North Creek District is comprised largely of level outwash landforms, with fewer wetlandsand forest than the western portion of the city. A small man-made lake named Valley Lake islocated in the north-central part of the North Creek District and drains to North Creek. A largewetland (19-349W) located east of Pilot Knob Road also drains to North Creek.The district is drained by North Creek, a tributary of the Vermillion River and falls under thejurisdiction of the Vermillion River Watershed Joint Powers Organization (VRWJPO). The creekhas two branches; the West Branch of North Creek is a perennial stream fed by groundwaterdischarge during dry weather, and the Main Branch has more intermittent flow.The West Branch of North Creek begins in the western portion of the district, between Highviewand Ipava Avenue, and flows east. The West Branch roughly divides the district west to eastbefore entering the city of Farmington east of Pilot Knob Road.The Main Branch extends north into Apple Valley. The watershed of the Main Branch includes asignificant portion of the city of Apple Valley, extending as far as Alimagnet Lake. The MainBranch joins the West Branch about ½ mile downstream from Pilot Knob Road. The city ofLakeville Water Resources Management Plan Page 3-9

Apple Valley constructed a 60-inch storm sewer to convey Main Branch flow from a 10-acrestormwater pond north of County Road 46 to Wetland 19-349W, located east of Pilot Knob Road.The sewer follows the pre-existing channel alignment.The western two-thirds of the North Creek District is developed primarily for residential use.The eastern third is generally agricultural, with the exception of a gravel mining operation in theextreme northeast corner of the city.3.4.4 Farmington Outlet Stormwater DistrictThe Farmington Outlet District is located east of Ipava Avenue and extends to the boundary withthe city of Farmington, between 202 nd Street West and 175 th Street West. The district lies withinthe Vermillion River Watershed and falls under the jurisdiction of the VRWJPO. There are nolarge surface water bodies within this district. Drainage from the Farmington Outlet Districtflows east in existing channels through the city of Farmington into the Middle Creek portion ofthe Vermillion River, which discharges to the Mississippi River.Drainage from this district flows in three main channels. Drainage from west of Dodd Boulevardis collected in the northern channel and flows directly east at 182 nd Street West. The centralchannel collects runoff from areas adjacent to 190 th Street, and flows east. Runoff from areasbetween 195 th and 200 th Street West is collected in the southern channel and flows east.The Farmington Outlet District covers approximately 3,410 acres, which is mainly agriculturalland. The future land use is projected to be primarily low to medium density residential.3.4.5 Lake Marion Stormwater DistrictThe total area of the Marion Lake District, including the lake itself, is 4,987 acres, 4,791 of whichlie within the city of Lakeville. The remaining 196 acres lie in Credit River Township in ScottCounty. The district extends approximately from 210 th Street West in the south to Lake VillaGolf Estates in the north, and from Dodd Boulevard in the east to Credit River Township in thewest. It drains ultimately to the Vermillion River and falls under the jurisdiction of theVRWJPO.The Marion Lake watershed occupies a transitional zone within the city between the rolling hills,hardwood forests, and abundant wetlands of the northwestern part of the city and the leveloutwash landforms of eastern and southern Lakeville. Many of the sub-watersheds within theLake Marion District contain ponds or wetlands that act as storage areas during shorter-durationrain events. Runoff is ultimately stored in Lake Marion during larger precipitation events.Runoff enters Lake Marion at various points. The largest tributaries enter at the southwestcorner of the lake. Many smaller inflows are scattered around the perimeter of the lake.The area to the southwest of Lake Marion contains agricultural and forest areas along with rural,single-family housing. The area to the north and east of the Lake is more developed with theLakeville Water Resources Management Plan Page 3-10

Lakeville Commerce Center and residential use. The corridor along I-35 contains some lightindustry and commercial business.The boundaries of the Lakeville Stormwater Districts are shown on Figure 3.4.1. More detailon the drainage system is contained in Section 4 of this plan.3.4.6 South Creek Stormwater DistrictThe South Creek District extends from the southern boundary of the city northward to between215 th Street West and 185 th Street West. The district lies within the Vermillion River Watershedunder the jurisdiction of the Vermillion River Watershed Joint Powers Organization (VRWJPO).Drainage from the South Creek District flows into the Vermillion River, which discharges to theMississippi River. Portions of the South Creek in this district of Lakeville are designated as troutstream by the MnDNR.Runoff from the majority of this district flows in channels to the Vermillion River. Runoff from76 acres in the southwest corner of the city flows to the southwest into the Credit River Townshipand eventually discharges to the Vermillion River.There are three main channels within this district that outlet to the east into the city ofFarmington. The main channel is referred to locally, and in this plan, as South Creek. The mainchannel begins west of I-35 near the city boundary with New Market Township and flows eastthrough Airlake Industrial Park. At the regional scale this channel is often referred to as theNorth Branch of South Creek. In this plan, the North Branch of South Creek refers to thechannel that begins north of 192 nd Street between Dodd Boulevard and Kenwood Trail andcontinues to the southeast, eventually flowing into South Creek just south of Highway 50between Hamburg Avenue and Cedar Avenue.The other two channels exit the city just north and south of South Creek, and are referred to asthe South Branch of South Creek and the East Branch of South Creek. The South Branch ofSouth Creek drains approximately 2,467 acres, including roughly 1,527 from New Market andEureka Townships. Approximately 602 acres is tributary to the East Branch of South Creek. Themain channel and North Branch of South Creek drain approximately 4,865 acres, includingabout 23 acres from New Market Township.Outflow from Lake Marion enters the south branch south of Highway 50, west of HolyokeAvenue. The outlet from Marion Lake is 1 foot below the Ordinary High Water Level (OHW) of983.1.Agriculture accounted for about 34% of land use in the South Creek District in 2006. Almost1600 of those approximately 2150 acres of agricultural land will be included within the 2010MUSA boundary. Residential areas, mostly single family and low density, currently occupyanother 28% of the watershed. Another 13% contains commercial or industrial areas, mainlyLakeville Water Resources Management Plan Page 3-11

within the downtown area and the Airlake Industrial Park. The remainder is large made up offorest, grassland and developed parks.Estimated future land use changes for the South Creek Water District include 57% increase inresidential land use as well as large increases in commercial and industrial land use. Agriculturalland use is expected to decrease to approximately 25% of its 2006 level.3.5 SOILSSoil composition, slope, and land management practices determine the impact of soils on waterresource issues. Soil composition and slope are important factors affecting the rate and volume ofstormwater runoff. The shape and stability of aggregates of soil particles, expressed as soil structure,influence the permeability, infiltration rate, and erodibility of soils. Slope is important indetermining stormwater runoff rates and, hence, the soil’s susceptibility to erosion.Infiltration capacities of soils affect the amount of direct runoff resulting from rainfall. The higherthe infiltration rate for a given soil, the lower the runoff potential. Conversely, soils with lowinfiltration rates produce high runoff volumes and high peak discharge rates. Four general soilhydrologic groups have been established by the Natural Resources Conservation Service (NRCS—formerly the Soil Conservation Service). These groups are: Group A Low runoff potential—high infiltration rate Group B Moderate infiltration rate Group C Slow infiltration rate Group D High runoff potential—very slow infiltration rateThe hydrologic grouping symbols (A-D) are combined with land use and used to estimate the amountof runoff that will occur over a given area for a particular rainfall amount. The various soil typeslocated in the city were determined from the Soil Survey of Dakota County, Minnesota (SCS, 1983).The Dakota County soil survey lists the hydrologic soil groups in its tables, but does not map the soilsaccording to these groupings.Urbanization changes the character of soil typically resulting in decreased infiltration rates. As landis developed for urban use, much of the soil is covered with impervious surfaces, and soils in theremaining areas can be significantly altered. Development often results in consolidation of the soiland tends to reduce infiltration capacity of otherwise permeable soils, resulting in significantlygreater amounts of runoff. Grading, plantings, and tended lawns tend to dominate the landscape inurbanized areas and may become more important factors in runoff generation than the original soiltype.Lakeville Water Resources Management Plan Page 3-12

The soil types present within the city of Lakeville are grouped by hydrologic group in Figure 3.5.1.Most of the city is composed of mainly Group B soils. Group D soils are mixed with Group B soilswhere swales occur, especially along South Creek, North Creek, and channels in the FarmingtonOutlet District. Class A soils occupy less than 10% of the city and are localized around Lake Marion,between Lee and Crystal Lakes, and near the gravel pits in the far northeast corner of the city. Thefew areas where Class C soils are found are limited to the upland areas in the center of the city and inthe far southwest corner of the city.There are many different soil types within each hydrologic group. The Dakota County soil surveyshows that the soils of the city of Lakeville generally consist of well-drained soils formed in loamyand sandy glacial till and outwash from three different units: the Kingsley-Mahtomedi unit, theOstrander-Klinger-Maxfield complex, and the Waukegan-Wadena-Hawick complex. It should benoted that these soil units are named for the major soil types present but contain many unique soiltypes in varying amounts and patterns.The western half of the city generally falls under the Kingsley-Mahtomedi unit, with the majority ofthe area underlain by Kingsley sandy loam. The Dakota County soil survey indicates soils of theOstrander-Klinger-Maxfield complex are present in the eastern half the city. Soils here demonstratemore variety, but Ostrander loam and Klinger silt loam are common. The lower sections of NorthCreek and South Creek occupy the Waukegan-Wadena-Hawick complex and are dominated byWaukegan silt loam. The following generalized soil and land descriptions are taken from the countysoil maps.Kingsley-Mahtomedi soils are generally loamy and sandy soils, which are well drained andmoderately coarse-textured. These soils are generally found on gently sloping to very steep land,much of it urban, and are also found on uplands. Kingsley soils typically consist of an eight-inchthick surface layer of black sandy loam, followed by a four-inch thick subsurface layer of brownloamy sand, followed by a 26-inch thick subsoil. The subsoil is dark brown and reddish brown sandyloam in the upper part, and dark brown sandy loam in the lower part. The underlying material isdark brown sandy loam with layers of loamy sand. The permeability of this Kingsley soil is moderatein the surface layer and moderately slow in the subsoil and underlying material. The available watercapacity is moderate and runoff rapid. Erosion, complex slopes, and susceptibility to drought makeKingsley-Mahtomedi soils generally poorly suited to crop cultivation.Ostrander-Klinger-Maxfield soils are generally silty and loamy soils which may be well-drained,somewhat poorly-drained or poorly-drained. These soils are found on nearly level or sloping terrainand uplands. Ostrander soils generally consist of a 13 inch surface layer of black loam, underlain bya four-inch thick subsurface layer of very-dark grayish brown loam about 36-inches thick. Thesubsoil consists of yellowish brown, calcareous loam to a depth of about 60 inches. Soft sandstonebedrock is present in some locations at depths between 40 and 60 inches. The Ostrander soil ismoderately permeable, with high water capacity and rapid runoff. There is a moderate amount oforganic matter in Ostrander soils, which are well suited to their common use as cropland. Erosionprevention is the primary management concern.Lakeville Water Resources Management Plan Page 3-13

Waukegan-Wadena-Hawick soils are generally silty, loamy, and sandy soils, which are well drainedto excessively drained soils found on level to very steep land on outwash plains and terraces.Waukegan soils are similar to Kingsley soils; they are well drained silt loams with a bottom layer ofgravelly sand. Wadena soils are also well drained loams, sandy loams and loamy sands, while Hawicksoils are sandy loams, loamy sands and gravelly sands. These soils are suitable for individual sewagetreatment systems (ISTS), although Wadena and Hawick soils should be tested to assure the soil willfilter the effluent. Waukegan-Wadena-Hawick soils are well suited for crop cultivation, as well asroad and building construction.More information about soils can be obtained from the Dakota County soil survey.3.6 GEOLOGY AND GROUNDWATER RESOURCESThe geology of Lakeville consists of three major units: 1) Quaternary or surface geology whichincludes all of the (primarily glacial) deposits above the bedrock formations; 2) Paleozoic or bedrockgeology which includes several layers of dolomite and sandstone; and 3) Proterozoic or basementgeology which includes basalts and crystalline igneous rocks.Subcropping bedrock is the first bedrock encountered below the overlying soils. The subcroppingbedrock units in the city of Lakeville are sedimentary in origin and include the Platteville andGlenwood formations, the St. Peter sandstone, and the Prairie du Chien dolomite (see Figure3.6.1). The youngest subcropping bedrock unit, the Platteville and Glenwood formations, occur inthe north part of the city. The St. Peter formation covers approximately half of the city and isconcentrated in the northeast, while the Prairie du Chien formation occurs primarily in the southernand eastern parts of the city. All of these bedrock units are sedimentary rocks deposited by shallowseas during Paleozoic Era, approximately 225 to 600 million years ago. The bedrock formationsform part of a gently sloping bowl-like structure centered under the Minneapolis-St. Paulmetropolitan area, known as the Twin Cities Basin. The Dakota County geologic atlas contains moreinformation about the subcropping bedrock units.The geologic formations above the bedrock are primarily glacial deposits consisting of till or outwash(see Figure 3.6.2). Mixed outwash of the Des Moines and Superior Lobes underlies much of theNorth Creek and South Creek Districts, where the topography transitions smoothly from uplands tolowland swales. This formation encompasses some of the lower areas of the Crystal Lake and LakeMarion Districts. The Crystal Lake District and Lake Marion District also contain mixed till from theDes Moines Lobe. This till lies beneath most of the city west of I-35. Thin-mantled till of the DesMoines Lobe (less than 50 feet thick in most places) is concentrated near the center of the city andunderlies much of the Farmington Outlet District. The eastern part of the Farmington Outlet Districtsits atop “old gray” till. Stratified ice-contact deposits as much as 150 feet thick occur in the farnorthwest corner of the city in the Orchard Lake District. Outwash from the Superior Lobe occupiesLakeville Water Resources Management Plan Page 3-14

the extreme northeast corner of the city. The Dakota County geologic atlas contains moreinformation about the surficial geology units.3.6.1 Groundwater ResourcesTwo types of aquifers are present in the city of Lakeville: surficial (quaternary) aquifers andbedrock aquifers. The following paragraphs provide general information about the aquifers in thecity. For more information refer to the Dakota County geologic atlas and the Dakota CountyGroundwater Protection Plan.3.6.1.1 Surficial (Quaternary) AquifersSurficial (quaternary) aquifers are water-bearing layers of sediment, usually sand and gravel,which lie close to the ground surface. Recharge to the surficial aquifers is primarily throughthe downward percolation of local precipitation. Some surficial aquifers may also berecharged during periods of high stream stage. A large number of ponds and lakes arescattered throughout the western part of the city and recharge the groundwater. Some ofthese water bodies are landlocked and their only outlet is to the groundwater. Surficialaquifers may discharge to local lakes, streams or to the underlying bedrock.The highest yielding surficial aquifers aregenerally located in buried bedrock valleys.Water yield from surficial aquiferssurrounding Lake Marion, Crystal Lake,Orchard Lake, and some reaches of SouthCreek may be between 250 and 500 gallonsper minute (gpm). Measured water yields inA surficial aquifer is a water-bearinglayer of sediment, usually consisting ofsand and gravel, that is close to thesurface. Rain and snowmelt are theprimary sources of recharge to asurficial aquifer.the south and west parts of the city are generally higher than those measured in the centraland northeastern parts of the city, where yield is less than 5 gpm in many areas.Many domestic wells in the city (see Figure 3.6.1) draw water from surficial aquifers. Manyprivate drinking water wells were constructed in surficial aquifers, especially thoseconstructed prior to the first state Well Code in 1974. Since the surficial aquifers are moresusceptible to pollution, they are not used for municipal or public supply wells.3.6.1.2 Bedrock AquifersTwo major bedrock aquifers are used for water supply in the city of Lakeville: the Prairie duChien-Jordan, and the St. Peter. Many private wells in central and northeast Lakeville utilizethe St. Peter sandstone (see Figure 3.6.1). The Prairie du Chien-Jordan aquifer is usedthroughout the rest of city of Lakeville. The Prairie du Chien is confined in most areas, hashigh yields, has very good water quality and is continuous through most of the city. Themajority of Lakeville’s municipal wells are drilled into the Jordan sandstone of this aquifer.Lakeville Water Resources Management Plan Page 3-15

A bedrock aquifer is a layer of bedrockthat is porous enough to contain waterin the spaces between rock grains and infractures.The groundwater level in the Prairie duChien-Jordan aquifer varies from about700 feet to more than 800 feet above meansea level as shown in the county geologicatlas. The aquifer is recharged in areaswhere thin permeable drift overlies the limestone layers. Some recharge of this aquiferoccurs locally from percolation through the overlying glacial deposits or St. Peter sandstone.However, hydrogeologic considerations suggest this recharge would be a minimalcontribution to the aquifer flow. Regional recharge of the Prairie du Chien-Jordan aquiferoccurs to the south, in Freeborn and Mower Counties. Groundwater movement in the aquiferhere is generally from south to north.Static water levels in the St. Peter aquifer may be 10 to 40 feet higher than in the Prairie duChien-Jordan aquifer. Groundwater movement in this aquifer generally follows that of thePrairie du Chien-Jordan. The St. Peter aquifer varies between confined and unconfinedconditions depending on location. Recharge is greatest where the aquifer is covered by sandand may be enhanced by overlying lakes.3.7 FOREST RESOURCES AND NATIVE VEGETATIONPre-settlement data available from the DNR classifies vegetation in the city of Lakeville around theyear 1895 as oak openings and barrens, prairie and wet prairie. Pre-settlement vegetation in theeastern half of the city is primarily prairie. The pre-settlement vegetation present in western half ofthe city of Lakeville is primarily oak openings and barrens. Oak openings occur on rich, dry-mesic tomesic soils and are dominated by grasses, forbs, brush, and scattered large trees of mostly bur andwhite oak. Oak openings have less grass and more forbs and woody shrubs than prairie, but moregrass and fewer forbs than forests. Isolated areas of wet prairie occur in the far northeastern cornerof the city, along the Farmington-Lakeville border north of South Creek, and around Orchard Lakeand Lake Marion.Land use data updated in 2006 for the city of Lakeville classifies approximately 2,450 acres as forestand approximately 1,500 acres as grassland. This classification system, however, does not accountfor resources located in areas classified as another primary land use, which may be significant.Estimated land use changes in the city of Lakeville occurring between 2006 and 2020 include theconversion of some forested areas to rural residential and single-family residential areas (seeSection 3.1). Both land use and land cover must be considered to accurately measure changes tothe landscape and its forest and vegetative resources.Lakeville Water Resources Management Plan Page 3-16

3.8 MDNR PUBLIC WATERSPublic watersPublic waters are all water basins and watercourses thatmeet the criteria set forth in Minnesota Statutes, Section103G.005, subd. 15 that are identified on Public WaterInventory maps and lists authorized by MinnesotaStatutes, Section 103G.201.Public waters wetlandsPublic waters wetlands include all type 3, type 4, andtype 5 wetlands (as defined in U.S. Fish and WildlifeService Circular No. 39, 1971 edition) that are 10 acres ormore in size in unincorporated areas or 2 ½ acres ormore in size in incorporated areas (see MinnesotaStatutes Section 103G.005, subd. 15a and 17b).The MDNR designates certain waterresources as public waters to indicatethose lakes, wetlands, and watercoursesover which the MDNR has regulatoryjurisdiction. By statute, the definition ofpublic waters includes “public waters”and “public waters wetlands” (see box atleft).The MDNR uses county-scale maps toshow the general location of the publicwaters and public waters wetlands(lakes, wetlands, and watercourses)under its regulatory jurisdiction. Thesemaps are commonly known as PublicWaters Inventory (PWI) maps. Theregulatory “boundary” of these watersand wetlands is called the ordinary high water level (OHWL). PWI maps are available on a countyby-countybasis from the MnDNR’s website(http://www.dnr.state.mn.us/waters/watermgmt_section/pwi/maps.html).There are nine uniquely identified public waters partially or completely within the city of Lakeville:Crystal Lake, Horseshoe Lake, Kingsley Lake, Lee Lake, Lake Marion, Orchard Lake, and threeunnamed basins. Additionally, there are 47 uniquely identified public water wetlands within the cityof Lakeville. MDNR public waters within the city of Lakeville are presented in Figure 3.8.1.3.9 WETLANDSCombined data from the Vermillion River Watershed Joint Powers Organization (VRWJPO), BlackDog Watershed Management Organization (BDWMO), and the City of Lakeville list more than 450uniquely identified wetlands within the city of Lakeville (see Figure 3.9.1).3.9.1 Wetlands by Stormwater DistrictApproximately 350 wetlands, all located within the 2020 Metropolitan Urban Services Area(MUSA), have been evaluated and classified by the City of Lakeville Wetland Management Plancompleted in 2003. Omission of any wetland from the City of Lakeville Wetland ManagementPlan does not indicate the absence of a wetland, nor does it permit impacts to wetlands omittedfrom this inventory without proper regulatory procedure. Site-specific wetland inventory andLakeville Water Resources Management Plan Page 3-17

assessment is required prior to the development of any area regardless of its inclusion oromission from the City of Lakeville Wetland Management Plan. For more details on the WetlandPlan see Section 5.4.Crystal Lake WetlandsThirty-four wetlands were assessed within the Crystal Lake Stormwater District. The totalwetland acreage within this district is 42.7 acres, or roughly 3% of the area within the district.About half the wetlands in this district demonstrate high or average vegetative diversity andwildlife habitat functions as well as high or average water quality protection and floodattenuation functions. The remaining wetlands have functions either skewed towards vegetativeand wildlife functions or stormwater management functions. One wetland is classified as havingrestoration potential.Orchard Lake WetlandsAbout 110 wetlands were assessed within the Orchard Lake Stormwater District as part of theWetland Management Plan. The total wetland acreage within this district is 309 acres, or nearly15% of the watershed area within the district. Over 60 of the assessed wetlands show acombination of high or average vegetative/wildlife functions and high or average stormwaterfunctions. About 20 wetlands possess the highest vegetative diversity and wildlife habitatfunctions with little stormwater function. A similar number of wetlands exhibit the highest waterquality protection and flood attenuation functions with little vegetative/wildlife function. Thereare five potential wetland restoration sites in the Orchard Lake Stormwater District.Lake Marion WetlandsOver 100 wetlands were assessed within the Lake Marion Stormwater District as part of the 2003City of Lakeville Wetland Management Plan. The total wetland acreage within this district is 190acres, or 4% of the district. About half of these wetlands possess “some function for vegetativediversity and wildlife habitat with high functions for water quality protection and floodattenuation”. Another 20 wetlands have this combination of functions with the emphasisreversed, while the remainder are evenly split between either vegetative/wildlife functions andstormwater functions. There are five potential wetland restoration sites in the Lake MarionStormwater District. Wetlands in the western portion of this district were not assessed, as thisarea is currently largely undeveloped.North Creek WetlandsJust over 50 wetlands were assessed within the North Creek Stormwater District. The totalwetland acreage within this district is 351 acres, or 6% of the district. The majority of this areaoccurs along the banks of North Creek, especially upstream. Nearly 75 percent of the wetlands inthis district display a combination of both significant vegetative/wildlife functions andstormwater functions. The remaining wetlands are fairly evenly split between eithervegetative/wildlife functions and stormwater functions with little of the other. No wetlands inthis district are classified as restoration wetlands.Lakeville Water Resources Management Plan Page 3-18

South Creek WetlandsForty-one wetlands were assessed within the South Creek Stormwater District. The total wetlandacreage within this district is 237 acres, or approximately 4% of the district. The majority of thisarea occurs along South Creek. Nearly half of the wetlands in this district display “some functionfor vegetative diversity and wildlife habitat with high functions for water quality protection andflood attenuation”. Another eight wetlands along the West Branch of South Creek have afunctional classification based on their location along South Creek, which is a designated troutstream. Other wetland in the South Creek Stormwater District are have either vegetative/wildlifefunctions and stormwater functions with little of the other. One wetland in this district isclassified as a restoration wetland.Farmington Outlet WetlandsApproximately 46 acres of wetland in the Farmington Outlet Stormwater District wereinventoried. About half of this area belongs to a single wetland classified for restoration. Theremaining wetland areas possess a combination of both significant vegetative/wildlife functionsand stormwater functions. Much of the Farmington Outlet Stormwater District was notevaluated due to its exclusion from the 202o Metropolitan Urban Services Areas (MUSA). Asthis area is developed, additional wetland assessment will be required.3.10 SURFACE WATER SYSTEMThe city of Lakeville is split between two watersheds: the Vermillion River watershed, and the BlackDog watershed (see Figure 5.13). The Vermillion River watershed flows ultimately to theMississippi River and the Black Dog watershed flows to the Minnesota River. The watershed divideplaces about 6 square miles in the northwest part of the city within the within Black Dog and thegreater Minnesota River watershed. This area includes the Orchard Lake and Crystal LakeStormwater Districts. These watersheds generally drain north and west to the Credit River. Theremaining areas of the city belong to the Vermillion and ultimately the Mississippi River watershed.These watersheds generally drain to the southeast.3.10.1 LakesThere are six major lakes completely or partially located within the city of Lakeville: CrystalLake, Kingsley Lake, Lee Lake, Lake Marion, Orchard Lake, and Valley Lake (see Figure3.10.1).Crystal Lake is approximately 300 acres in size. Most of that area lies within the city ofBurnsville, but approximately 9 acres of area and a half mile of shoreline are located within thecity of Lakeville.Lakeville Water Resources Management Plan Page 3-19

Kingsley Lake, which is wetland-like in character, has an open water area of about 44 acres. Thisarea grows to nearly 80 acres when the adjacent wetland area included. Kingsley Lake has amaximum depth of 13 feet and a tributary watershed area of 193 acres. The lake drains intoOrchard Lake by a culvert located at the ordinary high water level (OHW) of 987.5 feet.Lee Lake is 25 acres in size with a tributary watershed of 313 acres. It has a maximum depth of17 feet. There is no public boat access to this lake, and motors are limited to 10 horsepower. LeeLake is part of the Crystal Lake watershed.Lake Marion is the largest lake in the city of Lakeville with an area of 560 acres and a maximumdepth of 21 feet. Lake Marion is bounded by several parks and includes public boat access, abeach, and three fishing piers. Lake Marion is located in the southeast corner of itsapproximately 8 square mile tributary watershed. Lake Marion outlets into a channel whichjoins South Creek (regionally known as the North Branch of South Creek) before leaving the cityof Lakeville. Lake Marion is considered a “high priority” lake by the Metropolitan Council due toits multi-recreational use.Orchard Lake is located in the northwest corner of the city of Lakeville. It has an area of 234acres and a tributary watershed of approximately 3 square miles. It is the deepest lake inLakeville, with a maximum depth of 33 feet. The lake is used for recreation and has a swimmingbeach and concrete boat launch.Valley Lake is a small lake approximately 8 acres in size and with a maximum depth of 10 feet.Valley Lake receives flow from a 117-acre tributary watershed located in the North Creek District.This is a man-made lake with a swimming beach and fishing pier.3.10.2 StreamsThe city of Lakeville contains over 51 miles of streams as delineated by the MnDNR (see Figure3.10.1). All of these streams are located in the North Creek District, Farmington Outlet District,Lake Marion District, or the South Creek District. Several intermittent streams drain to LakeMarion from the uplands located to the northeast and southwest of the lake. In the North CreekDistrict, North Creek flows from west to east for approximately 6 miles before enteringFarmington. Along that path, various intermittent streams enter from the north and south,including discharge from Valley Lake. Several intermittent streams drain west from the centraluplands east towards Farmington in the Farmington Outlet District. These parallel-flowingchannels are all considered part of Middle Creek and merge in Farmington before discharging tothe Vermillion River. In the South Creek district, there are three channels that drain from westto east into the city of Farmington. The main channel, referred to as South Creek, flows fromwest to east along the south side of the city and is joined by the North Branch of South Creek(which flows southeast from the uplands located in the center of the city) near the southeastcorner of the city. South Creek and the North Branch of South Creek together drain a watershedof about 4,900 acres. The South Branch of South Creek drains another 2,500 acres, over 1,500 ofwhich lie within New Market and Eureka Townships. The East Branch of South Creek has aLakeville Water Resources Management Plan Page 3-20

much smaller tributary area of roughly 600 acres. All three channels lie within the VermillionRiver Watershed and are under the jurisdiction of the Vermillion River Watershed Joint PowersOrganization (VRWJPO). In addition, all three channels are designated as trout streams ortributaries to trout streams.3.11 WATER QUALITY3.11.1 Water Quality Sampling Program3.11.1.1 Citizen Assisted Monitoring Program (CAMP)The CAMP program is run by the Metropolitan Council with funding from the City ofLakeville and the Black Dog Watershed Management Organization. Through this program,volunteers and City staff monitor the water quality of local waterbodies and submit collecteddata and samples to the Metropolitan Council to be analyzed. In Lakeville, Lake Marion, LeeLake, Kingsley Lake, Orchard Lake, Valley Lake and wetland 349W are included in CAMP.Resident volunteers or City staff collect bi-weekly samples and record important informationsuch as water clarity, temperature, and recreational suitability. Lakes are monitored frommid-April to mid-October each year. The Metropolitan Council analyzes collected water fortotal phosphorus, total Kjeldahl nitrogen, and chlorophyll-a for each lake and analyzes thedata to determine a letter grade for the water quality of each lake. Data collection andanalysis has been conducted by Metropolitan Council since 1980, so current data collectedcan be compared to past data to determine trends of in-lake water quality. Data collected isretained by Lakeville Environmental Resources staff.3.11.1.2 Wetland Health Evaluation Program (WHEP)The WHEP program is funded by Dakota County, Hennepin County, EPA Region 5, andparticipating cities. There are eight participating cities in Dakota County. Four sites aremonitored in Lakeville twice during the growing season. There were nine volunteers on theLakeville WHEP team in 2006. These trained volunteers participate in plant andinvertebrate surveys and spent a total of 193.25 hours monitoring in the 2006 season. Thedata collected is used to determine trends over time and provide a general overview ofwetland health in the area. Data from previous years of monitoring is kept on file byLakeville Environmental Resources staff.3.11.1.3 Vermillion River WatchStudent and citizen volunteers are trained to collect and identify macro invertebrates,conduct habitat assessments and evaluate water quality. In years past, Kenwood Trail Jr.High and Lakeville North High School have been monitoring several different locations ontributary streams. Unfortunately in 2006, Kenwood Trail Jr. High could no longerparticipate in the program. Lakeville High School did participate in 2006. The datacollected is analyzed by the students and is used to track water quality changes. The goals ofthe program are to increase awareness about the Vermillion River, educate the public, andLakeville Water Resources Management Plan Page 3-21

provide data to local government agencies. The Vermillion River Watershed Joint PowersOrganization supports and funds this program along with Dakota County PhysicalDevelopment Division, Dakota County Soil and Water Conservation District, Dakota Electric,Castle Rock Bank, and the DNR Volunteer Stream Monitoring Program.3.11.1.4 City Water Resource MonitoringThere are six lakes and wetlands in Lakeville that are monitored by Lakeville EnvironmentalResources staff and by Blue Water Science: Kingsley Lake, Lake Marion, Lee Lake, OrchardLake, Valley Lake and wetland East 349W. Blue Water Science conducts aquatic plantsurveys, iron treatment studies, barley straw/organic carbon amendment studies, shorelandinventories, and curlyleaf harvesting summaries. Environmental Resources staff performwater quality and dissolved oxygen monitoring, assists with DNR fish surveys, and conductsshoreline restorations.3.11.2 Water Quality Data summary3.11.2.1 Crystal LakeWater quality data for Crystal Lake date back to 1957. Regular water quality sampling hasbeen performed since 1972 by various organizations including the Metropolitan Council,DNR, MPCA, as well as citizen monitoring programs. Water quality data for Crystal Lake isavailable from the Minnesota Pollution Control Agency electronically athttp://www.pca.state.mn.us/data/edaWater/index.cfm (station ID: 19-0027). Data sourcesand years of observation are presented in Table 3.11.1.Table 3.11.1Available data for Crystal Lake by collecting agencyParameterSampling Dates by Collecting OrganizationMnDNR MPCA Met Council CLMPAlkalinity 1957, 1975 1972-1987 1980-1989BOD 1972-1974Cadmium 1972-1974Calcium 1972-1985Chloride 1972-1987 2002-2006Chlorophyll-a 1980-1987 1980-2006Chlorophyll-b 2006Chlorophyll-c 2006Copper 1972-1974Depth, bottom 1980-1987 2006Depth, Secchi 1957, 1975 1974-1987 1980-2006 1973-2006DO 1957, 1975 1972-1987 1980-2006Fecal Coliform 1972-1974Lakeville Water Resources Management Plan Page 3-22

ParameterFluoride 1972Sampling Dates by Collecting OrganizationMnDNR MPCA Met Council CLMPHardness 1980 1972-1985Iron 2006Lead 1985Magnesium 1985MBAS 1972-1974Nickel 1972-1974Nitrogen, NH 4 1972-1980Nitrogen, TKN 1980-1987 1980-2006 1979-1981Nitrogen, NO 3 1972-1987 1980-1983Nitrogen, organic 1972-1980Orthophosphate 2006pH 1972-1987 1980-2006Pheophytin-a 2001-2006Phosphorus 1972-1987 1980-2006 1979-1981Potassium 1972PhysicalAppearance1987 1999-2006 1987-2006RecreationalSuitability1987 1999-2006 1987-2006Redox Potential 2006Sodium 1972TSS 1972-1987VSS 1972-1987Spec. Conductance 1972-1987 1980-2006Sulfate 1972Temperature 1957, 1975 1972-1987 1980-2006Total Coliform 1972-1974Turbidity 1972-1987 2006Zinc 1972-1974The long-term mean total phosphorus concentration of Crystal Lake (measured May throughSeptember between depths of zero to 2 meters) is 0.044 mg/L, with annual averages rangingfrom 0.027 mg/L to 0.103 mg/L (see Figure 3.11.1). Individual samples as high as 1.4 mg/L(8/30/1995) have been recorded at the lake bottom. Figure 3.11.1 shows a decreasing trendin total phosphorus concentrations since the 1970s. This trend is more pronounced over thepast decade. Data on nitrogen to phosphorus ratios indicate that phosphorus is the limitingLakeville Water Resources Management Plan Page 3-23

nutrient for the growth of algae.Chlorophyll-a concentrations for summer conditions average 19 ppb, which, according topublished chlorophyll-phosphorus relationships for Twin Cities metropolitan area lakes, isappropriate to the observed phosphorus concentration.In the 2007 the mean summer Secchi disc transparency for Crystal Lake was 1.7 meters (5.6feet). For the period 1973-2007 mean summer Secchi disc transparency is 2.0 meters (6.6feet). Water transparency is typically highest in late spring and decrease steadily through thesummer. The seasonal cycle of water quality in Crystal Lake for 1989 and 1990 is presentedin Figure 3.11.2. Transparency measurements of approximately 3.5 meters are typical inmost years, but may reach minima of less than 1 meter in late summer. One meter is theapproximate Secchi disc transparency measurement below which lake use is severelyimpaired (Osgood, 1989). Transparency was first measured at or below 1 meter in August,1957. Average summer Secchi depth measurements for Crystal Lake show a slight decreasefrom 1973 to 2006 (see Figure 3.11.3). This trend is overshadowed by the seasonalvariability of Secchi depth, which can be as much as 5 meters (see Figure 3.11.2). Analysisfor trends in the data excluded the August 1957 date for Crystal Lake because these data weretoo far removed from the rest of the series.The lakes in Lakeville can be compared to the range of lakes in the metropolitan area toestimate their approximate rank with respect to water quality (Osgood, 1989). Incomparison to the 110 lakes that were sampled from 1980 through 1988, Crystal Lake issimilar to lakes in the 20th percentile, i.e., the lake has better water quality than 80 percentof the lakes in the metropolitan area.TSI estimates for Crystal Lake range from 46.5 to 59, with a median value of 54 from sevenindependent estimates in three sources. A report to the Black Dog Watershed ManagementCommission (OSM, 1990) estimated that the TSI for Crystal Lake was 46.5 when calculatedfrom Secchi transparency, 57.2 when calculated from phosphorus data, and 53.9 whencalculated from chlorophyll-a data. These three indices are reasonably consistent althoughclarity is relatively high in light of the phosphorus and chlorophyll-a readings. The dataindicate that the lake is moderately eutrophic with little or no use impairment. Any increasein trophic state could sharply reduce the use of the lake in late summer months, however.Qualitative water quality grades have been given for Crystal Lake based on summertimemonitoring results dating back to 1980. Those grades are summarized in Table 3.11.2.Lakeville Water Resources Management Plan Page 3-24

Table 3.11.2 Water Quality Summary for Crystal LakeYearTotalPhosphorusChlorophyllaSecchiDepthOverall1980 C C C C1981 C -- C --1982 -- -- C --1983 C B B B1984 -- -- C --1985 -- -- B --1986 -- -- B --1987 -- C C --1988 -- -- C --1989 B B B B1990 -- -- C --1991 -- -- B --1992 -- -- B --1993 -- -- -- --1994 C B C C1995 C C C C1996 C C C C1997 C C C C1998 C C C C1999 C B C C2000 C C C C2001 B B C B2002 C B C C2003 C C C C2004 C B C C2005 C C C C2006The collected data reveals no statistically significant trend in recent water quality, which hasreceived an overall grade of “C” in most years. One potential future problem is the presenceof Eurasian Water Milfoil, which has been reported in the lake and may interfere withrecreational activity.The relatively flat trend in Secchi depth, qualitative water quality grades and reduction intotal phosphorus are contrary to the expected pattern of increasing nutrient loading withLakeville Water Resources Management Plan Page 3-25

increased development of the watershed. Part of the reason for this stability may be due tothe fact that the amount of construction activity in the immediate watershed has beenreducing in recent years as Burnsville has attained ultimate development. Additionalimpacts from development may also be offset by the Black Dog WMO’s coordinating effortsto reduce nutrient loading from the watershed and to implement an alum treatment systemthat will help protect the lake from impacts of urbanization.3.11.2.2 Lee LakeLee Lake was landlocked, until 1993, when a gated outlet was constructed to Crystal Lake toreduce the peak flood level. At Elevation 947, Lee Lake has an area of approximately 22 acresand a maximum depth of approximately 17 feet. The outlet is described in more detail belowin Section II-F as part of the management of Watershed CL-12. Water quality data for LeeLake is available from the Minnesota Pollution Control Agency electronically athttp://www.pca.state.mn.us/data/edaWater/index.cfm (station ID: 19-0029). Data sourcesand years of observation are presented in Table 3.11.3.Table 3.11.3 Available data for Lee Lake by collecting agencyParameterSampling Dates byCollecting OrganizationMet CouncilChlorophyll-a 2001-2006Chlorophyll-b 2006Chlorophyll-c 2006Depth, Secchi 1994-1997, 2000-2006Nitrogen, TKN 1994-1997, 2000-2006Pheophytin-a 2001-2006Phosphorus 1994-1997, 2000-2006Physical Appearance 1994-1997, 2000-2006Recreational Suitability 1994-1997, 2000-2006Temperature 1994-1997, 2000-2006Lee Lake was labeled as nearly hypereutrophic in 1990, with a median TSI of 68.2, based onsix estimates in two sources. Compared to other lakes samples by the Metropolitan Council(Osgood, 1990b), Lee Lake would rank in the 10th to 20th percentile; i.e., it would havepoorer water quality than 80 to 90 percent of metropolitan lakes.The mean summer Secchi depth measured from 1994 to 2006 averaged 1.3 meters (seeFigure 3.11.4). The seasonal cycle is similar to Crystal Lake. Transparencies are high earlyin the year and decrease steadily through July and August. No significant trend is evidentover the span from 1994 to 2006, although Secchi transparency has improved annually since2003 (see Figure 3.11.4).Lakeville Water Resources Management Plan Page 3-26

The average summer total phosphorus concentration measured from 1994 to 2006 in LeeLake averaged 0.060 mg/L (measured at 0 to 6-foot depth). Annual averages have rangedfrom about 0.041 mg/L to 0.097 mg/L. Figure 3.11.5 shows that average epilimnetic totalphosphorus has increased over the past decade, in contrast to the Secchi transparency data.Qualitative water quality grades have been given for Lee Lake based on summertimemonitoring results dating back to 1994. Those grades are summarized below.Table 3.11.4 Water Quality Summary for Lee LakeYearTotalPhosphorusChlorophyllaSecchiDepthOverall1994 C C C C1995 C B C C1996 C B C C1997 C B C C1998 -- -- -- --1999 -- -- -- --2000 D C D D2001 C B C C2002 C B C C2003 C C C C2004 C C D C2005 D B C C2006Although the watershed of Lee Lake is now mostly developed, past farming operations arebelieved to have contributed to an internal phosphorus loading problem. Submerged aquaticvegetation (Curlyleaf Pondweed) is a continuing problem, both aesthetically and as a sourceof nutrients for algal populations.Lee Lake water quality has been consistently graded a “C”, except for in 2000. Nostatistically significant long term trends may be gleaned from the data. Overall water qualityhas not improved substantially since the beginning of barley straw treatment in 2003,although Secchi depth has increased. It is suspected that unusually high fish densities maybe impacting water quality, as fish removals in 2005 and 2006 coincided with improvedchlorophyll-a and Secchi depth measurements.Lakeville Water Resources Management Plan Page 3-27

3.11.2.3 Orchard LakeOrchard Lake has an area of 235 acres, a mean depth of 8.5 feet and a volume ofapproximately 2,100 acre-feet at elevation 976.6. Aquatic macrophytes are abundant,especially on the south side of the lake. The lake is normally dimictic, mixing only in thespring and fall. Water quality data for Orchard Lake is available from the MinnesotaPollution Control Agency electronically athttp://www.pca.state.mn.us/data/edaWater/index.cfm (station ID: 19-0031). Data sourcesand years of observation are presented in Table 3.11.5.Table 3.11.5 Available data for Orchard Lake by collecting agencyParameterSampling Dates by Collecting OrganizationMPCA Met Council CLMPAlkalinity 1987 1980-1989Aluminum 1980Arsenic 1980Barium 1980Boron 1980Cadmium 1980Chloride 1987 1980, 2006Chlorophyll-a 1987 1980-2006Chlorophyll-b 2006Chlorophyll-c 2006Chromium 1980Copper 1980Depth, bottom 1987Depth, Secchi 1987 1980-2006 1987-1991DO 1987 1980-2006Hardness 1980Iron 1980Lead 1980Manganese 1980Mercury 1980Nickel 1980Nitrogen, NH 4 1980-1983Nitrogen, TKN 1987 1980-2006Nitrogen, NO 3 1987 1980-1983Orthophosphate 2006pH 1987 1980-2006Lakeville Water Resources Management Plan Page 3-28

ParameterSampling Dates by Collecting OrganizationMPCA Met Council CLMPPheophytin-a 2001-2006Phosphorus 1987 1980-2006Physical Appearance 1987 1999-2006 1987-1991Recreational Suitability 1987 1999-2006 1987-1991Redox Potential 2006TSS 1987 1980VSS 1987 1980Spec. Conductance 1987 1980-2006SulfateTemperature 1987 1980-2006Turbidity 1987 1980, 2006Zinc 1980The long-term mean summer epilimnetic total phosphorus concentration of Orchard Lake is0.035 mg/L (measured between surface and 6 feet depth), with annual averages rangingfrom 0.025 mg/L to 0.049 mg/L. Data on nitrogen to phosphorus ratios indicate thatphosphorus is the limiting nutrient for the growth of algae. No trend in average epilimneticphosphorus concentration is evident in Orchard Lake (see Figure 3.11.6). Chlorophyll-aconcentrations for summer conditions average 17 ppb which, according to publishedchlorophyll-phosphorus relationships for Twin Cities metropolitan area lakes, is appropriateto the observed phosphorus concentration.Figure 3.11.7 demonstrates mean summer Secchi disc transparency is about 1.9 meters(6.2 feet). Seasonal data generally shows that water transparencies are high early in the yearand decrease steadily through June and July. Summer Secchi depths below 1 meter havebeen observed during eight of the seventeen years for which values were measured. Onemeter is the approximate Secchi disc transparency measurement below which lake use isseverely impaired (Osgood, 1989). Figure 3.11.7 shows an overall decline in Secchi depthsince 1980, although Secchi transparency has improved annually since 2003.TSI estimates for Orchard Lake range from 49.9 to 57, with a median of 52.4 from sixindependent estimates in three sources. This places the lake in the category of 50 to 70, aeutrophic (i.e., fertile) lake. However, the lake is barely in this category and in some years itwould be better classified as mesotrophic (i.e., moderately fertile). According to data fromthe Metropolitan Council (Osgood, 1989) Orchard Lake is comparable in water quality tolakes in the 20th to 30th percentiles in the metropolitan area. That is, its water quality isbetter than 70 to 80 percent of metropolitan area lakes. Like Crystal Lake, Orchard Lake isone of the better lakes in the region in terms of water quality.Lakeville Water Resources Management Plan Page 3-29

In 2006, user perception rankings described the physical condition of Orchard Lake assomewhere between “crystal clear” and “some algae present”. The recreational suitability ofthe lake was scored an average of 2.1 on a scale from 1 to 5, corresponding a ranking of as“minor aesthetic problem”. Qualitative water quality grades have been given for OrchardLake based on summertime monitoring results dating back to 1980. Those grades aresummarized in Table 3.11.6.Table 3.11.6 Water Quality Summary for Orchard LakeYearTotalPhosphorusChlorophyllaSecchiDepthOverall1980 C B C C1981 B B B B1982 -- -- -- --1983 B B B B1984 -- -- -- --1985 -- -- -- --1986 -- -- -- --1987 -- -- C --1988 -- -- C --1989 B B C B1990 -- -- D --1991 -- -- C --1992 -- -- -- --1993 C B C C1994 -- -- -- --1995 -- -- -- --1996 -- -- -- --1997 -- -- -- --1998 C C C C1999 C C C C2000 C C C C2001 B B B B2002 -- -- -- --2003 C C C C2004 C B B B2005 B B B B2006Lakeville Water Resources Management Plan Page 3-30

3.11.2.4 Kingsley LakeThe area of Kingsley Lake is 55 acres at the OHW; the lake is used for boating and canoeing,and is an important aesthetic resource. Kingsley Lake is believed to be the southernmostlake in Minnesota that is home to a nesting pair of loons. Kingsley Lake is eutrophic butthere is insufficient data to estimate the TSI. Water quality data for Kingsley Lake isavailable from the Minnesota Pollution Control Agency electronically athttp://www.pca.state.mn.us/data/edaWater/index.cfm (station ID: 19-0030). Data sourcesand years of observation are presented in Table 3.11.7.Table 3.11.7 Available data for Kingsley Lake by collecting agencyParameterSampling Dates by Collecting OrganizationMet CouncilCLMPChlorophyll-a 1993-2006Chlorophyll-b 2006Chlorophyll-c 2006Depth, bottom 2006Depth, Secchi 1993-2006 2006Dissolved Oxygen 1993Nitrogen, TKN 1993-2006pH 1993Pheophytin-a 2001-2006Phosphorus 1993-2006Physical Appearance 1995-2006 2006Recreational Suitability 1995-2006 2006Spec. Conductivity 1993Temperature 1993-2006The long-term mean summer total phosphorus concentration of Kingsley Lake is 0.019 mg/L(measured between surface and 6 feet depth), with annual averages ranging from about0.014 mg/L to 0.026 mg/L (see Figure 3.11.8). No trend is visible among the summer totalphosphorus data (see Figure 4.3.6).Kingsley Lake is believed to be thesouthernmost lake in Minnesota thatis home to a nesting pair of loons.Figure 3.11.9 demonstrates mean summerSecchi disc transparency is 2.4 meters (about8 feet). The data generally shows that watertransparencies are high early in the year anddecrease steadily through June and July. Summer Secchi depths have not been observedbelow 1.5 meters. One meter is the approximate Secchi disc transparency measurementbelow which lake use is severely impaired (Osgood, 1989). The long-term trend in SecchiLakeville Water Resources Management Plan Page 3-31

disc data for Orchard Lake shows improvement in Secchi transparency since 1993.Overall, Kingsley Lake has demonstrated good water quality, likely in part to a smallwatershed-to-lake-area ratio (4:1). The low Secchi transparency grades are the result of largeamounts of submerged macrophyte growth typical of wetlands, rather than suspendedparticulates or algae. This is augmented by the fact that, due to its shallow depth, the entirelake is considered littoral zone (area that may support aquatic vegetation). There do notappear to be trends in Kingsley Lake water quality, which averages a grade of A-B.Table 3.11.8 Water Quality Summary for Kingsley LakeYearTotalPhosphorusChlorophyllaSecchiDepthOverall1993 B A A A1994 -- -- -- --1995 B A B B1996 A A B A1997 A A B A1998 -- -- -- --1999 -- -- -- --2000 A A B A2001 A A C B2002 A A B A2003 B A B B2004 A A B A2005 A A B A20063.11.2.5 Lake MarionThe earliest water quality data for Lake Marion dates back to 1947. More frequent waterquality sampling has been performed since 1969. Lake Marion is considered a “HighPriority” Lake by the Metropolitan Council due to its multi-recreational use. Water qualitydata for Lake Marion is available from the Minnesota Pollution Control Agency electronicallyat http://www.pca.state.mn.us/data/edaWater/index.cfm (station ID: 19-0026-01 and 19-0026-02). Data sources and years of observation are presented in Table 3.11.9.Lakeville Water Resources Management Plan Page 3-32

Table 3.11.9 Available data for Lake Marion by collecting agencyParameterSampling Dates by Collecting OrganizationMnDNR MPCA Met Council CLMPChloride 1946, 1969 1987Chlorophyll-a 1987 1980-2006Chlorophyll-b 2006Chlorophyll-c 2006Depth, bottom 1987 2004Depth, Secchi 1969 1987 1980-2006 1977-2004Dissolved Oxygen 1969 1987 1980-1989Hardness 1946, 1969 1987 1980-1989Nitrogen, NH 4 1946, 1969 1980-1983Nitrogen, TKN 1946, 1969 1987 1980-2006Nitrogen, NO 3 1946, 1969 1987 1980-1983Orthophosphate 1946pH 1987 1980-1989Pheophytin-a 2001-2006Phosphorus 1946, 1969 1987 1980-2006Physical Appearance 1987 1994-2006 1989-2004Recreational Suitability 1987 1994-2006 1989-2004TSS 1987VSS 1987Spec. Conductance 1987 1980-1989Sulfate 1946, 1969Temperature 1969 1987 1980-2006Turbidity 1987The long-term mean summer total phosphorus concentration of Marion Lake at 0 to 3 feet isabout 0.036 mg/L with a annual average range of about 0.024 mg/L to 0.088 mg/L (seeFigure 3.11.10). Data on nitrogen indicate that phosphorus is the limiting nutrient foralgae growth. Chlorophyll-a concentrations for summer conditions average 21 ppb, which,according to published chlorophyll-phosphorus relationships for Twin Cities metropolitanarea lakes, is appropriate to the observed phosphorus concentration.Mean summer Secchi disc transparency is 1.9 meters (6.2 feet). Secchi depths in LakeMarion (see Figure 3.11.11) are typically high in the late spring and decrease through thesummer months. Seasonal minimum Secchi depths less than one meter occurred frequentlyLakeville Water Resources Management Plan Page 3-33

etween 1977 and 1991 and once more in 2005. One meter is the approximate Secchimeasurement below which lake use is severely impaired (Osgood, 1989). Based on Secchidisc data, severe use-impairment of Marion Lake is likely beginning in mid-July.Water quality data between 1977 and 2007 show a marked improvement in Secchitransparency. Figure 3.11.11 shows an average improvement of over 1 meter over the last20 years. During the same period, total phosphorus concentrations (see Figure 3.11.10) inLake Marion decreased. Despite the general downward trend, isolated high concentrationsof total phosphorus have been observed since 2003.Marion Lake is slightly more eutrophic than Crystal or Orchard Lakes in all of the studieswhere comparison is possible. TSI estimates for Marion Lake range from 53.1 to 67, with amedian of 57.9 from six independent estimates in three sources. This places the lake clearlyin the category of 50 to 70, a eutrophic lake.According to data from the Metropolitan Council (Osgood, 1989) Marion Lake is comparablein water quality to lakes in the 50th to 55th percentiles in the Metropolitan area. That is, itswater quality is better than 45 to 50 percent of the Metropolitan area lakes.Oxygen levels are now monitored during the winter because of past winter fish kills, and thelake is aerated when necessary. Qualitative water quality grades have been given for LakeMarion based on summertime monitoring results dating back to 1980. Those grades aresummarized below and show much variability in water quality over the past 25 years. Waterquality appears to be the best between 1994 and 2001. One potential future problem is thepresence of Eurasian Water Milfoil, which has been reported in the lake and may interferewith recreational activity.Table 3.11.10 Water Quality Summary for Lake MarionYearTotalPhosphorusChlorophyllaSecchiDepthOverall1980 C C C C1981 C D D D1982 -- -- -- --1983 C C B C1984 -- -- -- --1985 -- -- -- --1986 -- -- -- --1987 C C C C1988 -- -- -- --1989 C C C CLakeville Water Resources Management Plan Page 3-34

YearTotalPhosphorusChlorophyllaSecchiDepthOverall1990 -- -- C --1991 -- -- C --1992 -- -- -- --1993 -- -- -- --1994 B A B B1995 -- -- -- --1996 -- -- -- --1997 -- -- -- --1998 -- -- -- --1999 B B C B2000 B A B B2001 B B B B2002 C B C C2003 B C C C2004 C C C C2005 C C C C20063.11.2.6 Valley LakeWater quality monitoring was conducted in Valley Lake as part of CAMP from 1995-1997 and1999-present. Water quality data for Valley Lake is available from the Minnesota PollutionControl Agency electronically at http://www.pca.state.mn.us/data/edaWater/index.cfm(station ID: 19-0348). The dates, parameters, and reporting agency of the data are presentedin Table 3.11.11.Table 3.11.11 Available data for Valley Lake by collecting agencyParameterSampling Dates byCollecting OrganizationMetropolitan CouncilCarbon, total organic 2005Chloride 2002-2006Chlorophyll-a 1995-2006Chlorophyll-b 2006Chlorophyll-c 2006Depth, Secchi 1995-2006Nitrogen, TKN 1995-2006Lakeville Water Resources Management Plan Page 3-35

ParameterSampling Dates byCollecting OrganizationMetropolitan CouncilPheophytin-a 2001-2006Phosphorus 1995-2006Physical Appearance 1995-2006Recreational Suitability 1995-2006Temperature 1995-2006Summer Secchi transparency measurements have averaged just below 1.4 meters sinceobservation began in 1995 (see Figure 3.11.12). One meter is the approximate Secchimeasurement below which lake use is severely impaired (Osgood, 1989). Individual Secchidepth measurements below 1 meter occur with some frequency in Valley Lake, and Secchidepths below 0.5 meters have been observed in the past.Total phosphorus concentrations (measured from depths of 0 to 2 meters) in the summeraverage 0.067 mg/L for the same period (see Figure 3.11.13). The average summerconcentration of chlorophyll-a is 27 ppb. A TSI has not been estimated for Valley Lake.Water quality data for Valley Lake show two distinct trends between 1995 and 2006. Waterquality shows general improvement between 1995 and 2002. During this time, Secchitransparency increases by over 1 meter (see Figure 3.11.12), summer phosphorus levelsdecrease from an average of 90 ug/L to 45 ug/L (see Figure 3.11.13). After 2002, however,the opposite trends are observed. Secchi transparency decreased, while total phosphorusincreased.From 1999 to 2004 Valley Lake was involved in a barley straw pilot project aimed atinhibiting algal growth. Barley straw was added to the lake and water quality improvedduring the pilot project, except in 2005 when it is believed that an unusually large fishpopulation in 2005 negated the positive impacts. In 2005 crushed cornmeal was added toValley Lake instead because it is thought possesses similar qualities to barley straw but is lessexpensive. The improvements observed after the addition of barley straw are evident in thequalitative water quality measurements presented in Table 3.11.12.Lakeville Water Resources Management Plan Page 3-36

Table 3.11.12 Water Quality Summary for Valley LakeYearTotalPhosphorusChlorophyllaSecchiDepthOverall1993 -- -- -- --1994 -- -- -- --1995 D C D D1996 D C D D1997 C C D C1998 -- -- -- --1999 -- C D --2000 C B C C2001 C A C B2002 C A B B2003 C B B B2004 C C C C2005 C C C C2006Lakeville Water Resources Management Plan Page 3-37

3.11.2.7 North CreekThere is no water quality monitoring data available for North Creek prior to 2000. Since2000, it has been monitored by the MPCA. This data is available electronically from theMPCA at http://www.pca.state.mn.us/data/edaWater/index.cfm (station IDs: S003-348,S004-254, S004-255, S003-256). The dates, parameters, and reporting agency of the dataare presented in Table 3.11.13.Table 3.11.13 Available data for North Creek by collecting agency and locationParameterE. ColiFecalColiformStation IDSampling Dates byCollecting OrganizationMPCAS004-254 2006S004-255 2006S004-256 2006S003-328 2006S004-254 2006S004-255 2006S004-256 2006S003-328 2000, 2006Temperature S003-348 2005Transparency S003-348 2005-2006Samples taken in 2000, 2005, and 2006 averaged counts of approximately 6200 fecalcoliform per 100 ml of sample and 1500 E. coli per 100 ml of sample. Stream transparencywas greater than 60 cm in 36 of 74 samples, and averaged 42 cm among the other 38samples.In November 1992 grab samples were taken on the West Branch about one quarter mileupstream from Highview Avenue (south of Crystal Lake Golf Club); they showed that for baseflow conditions, the total phosphorus averaged 0.025 mg/L, total suspended solids averagedless than 7 mg/L and dissolved oxygen averaged 12.0 mg/L. The high water quality ischaracteristic of a groundwater base flow. Insufficient water quality data exists to evaluatelong term water quality trends in North Creek.3.11.2.8 South CreekA portion of South Creek extending from the Farmington-Lakeville border upstream to theconfluence with the West Branch of South Creek was designated a trout stream in 1983 bythe DNR (see Figure 3.14.1). Limited water quality data for South Creek is available fromthe MPCA at http://www.pca.state.mn.us/data/edaWater/index.cfm (station ID: S001-400).The dates, parameters, and reporting agency of the data are presented in Table 3.11.14.Lakeville Water Resources Management Plan Page 3-38

Table 3.11.14 Available data for South Creek by collecting agencyParameterStation IDSampling Dates byCollecting OrganizationMPCAFecal Coliform S001-400 1999-2000Temperature S001-400 1999, 2001-2003Transparency S001-400 1999, 2001-2003Stream clarity was greater than 60 cm in 38 of 92 samples and averaged ~45 cm in the other54 samples. Stream temperature averaged 9.8°C in March, 11.1°C in April, 12.8°C in May,16.5°C in June, 19.3°C in July, 19.9°C in August, 14.9°C in September, and 11.3°C in October.Fecal coliform counts averaged approximately 415, with the two highest values (2600 and2400) occurring in July of 1999.Water temperature is monitored in eight locations in South Creek. Temperature is recordedevery 10 minutes by Onset StowAway Temp loggers and HOBO Water Temp Pro V2 loggers.Temperature is monitored in the creeks to insure that water temperatures do not exceedcritical level of 73°F for more than 7 consecutive days. If temperatures remained above thecritical level for over 7 days, trout become stressed. Data can also used to track thermalchanges to the creek from surface water runoff, groundwater influence, and ambient airtemperature. Data collected in 2006 indicates that the water did not reach criticaltemperatures during the monitoring season. Water quality data was collected from SouthCreek at Cedar Avenue in 1990. That data is summarized in Table 3.11.15.Table 3.11.15 Summary of water quality data from South Creek at Cedar Ave (1990)Parameter Units Mean Range StandardDeviationBiological Oxygen Demand mg/L 6.1 4 – 8 4.2 – 8.8Specific Conductivity (25°C) µmohm/cm 681 650 – 705 653 – 711pH s.u. 8.07 8.0 – 8.2 7.96 – 8.18Total Suspended Solids mg/L 19.3 12 – 30 12.2 – 30.6Total Phosphorus µg/L 125 62 – 258 61 – 254Soluble Reactive Phosphorus µg/L 32 25 – 32 28 – 36More water quality data and information is available at the City of Lakeville web site:http://www.ci.lakeville.mn.us/departments/environmental.htmLakeville Water Resources Management Plan Page 3-39

Figure 3.11.1Crystal Lake average summer (May – September) total phosphorus concentrations, 0 – 2 meters0.1200.100Average Total Phosphorus (mg/L)0.0800.0600.0400.0200.0001970 1975 1980 1985 1990 1995 2000 2005 2010YearAverage Total Phosphorus (0 - 2 m, May - Sept) Trend (1973 - 2006)Lakeville Water Resources Management Plan Page 3-40

Figure 3.11.2 Seasonal variability in Secchi Depth, Crystal Lake, 1989 – 199054.543.5Secchi Depth (m)32.521.510.50Jan-89Feb-89Mar-89Apr-89May-89Jun-89Jul-89Aug-89Sep-89Oct-89Nov-89Dec-89Jan-90Feb-90Mar-90Apr-90May-90Jun-90Jul-90Aug-90Sep-90Oct-90Nov-90Dec-90Date1989 Seasonal Cycle 1990 Seasonal CycleLakeville Water Resources Management Plan Page 3-41

Figure 3.11.3 Crystal Lake average summer (June – September) Secchi Depth, 1973 – 20064.03.53.0Average Secchi Depth (m)2.52.01.51.00.50.01970 1975 1980 1985 1990 1995 2000 2005 2010YearAverage Secchi Depth (June - Sept) Trend (1973 - 2006)Lakeville Water Resources Management Plan Page 3-42

Figure 3.11.4 Lee Lake average summer (June – September) Secchi Depth, 1994 – 20062.52Average Secchi Depth (m)1.510.501992 1994 1996 1998 2000 2002 2004 2006 2008YearSummer Averages (June - September) Trend (1994 - 2006) Trend (2000 - 2006)Lakeville Water Resources Management Plan Page 3-43

Figure 3.11.5Lee Lake average summer (May – September) total phosphorus concentrations, 0 – 2 meters0.120.1Average Total Phosphorus (mg/L)0.080.060.040.0201992 1994 1996 1998 2000 2002 2004 2006 2008YearSummer Averages (0-2 m, May - Sept) Trend (1994 - 2006)Lakeville Water Resources Management Plan Page 3-44

Figure 3.11.6Orchard Lake average summer (May – September) total phosphorus concentrations, 0 – 2 meters0.060.05Average Total Phosphorus (mg/L)0.040.030.020.0101978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008YearAverage Total Phosphorus (0-2 m, May - Sept) Trend (1980 - 2006)Lakeville Water Resources Management Plan Page 3-45

Figure 3.11.7 Orchard Lake average summer (June – September) Secchi Depth, 1980 – 20063.532.5Average Secchi Depth (m)21.510.501978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008YearAverage Secchi Depth (June - Sept) Trend (1980 - 2006) Trend (1998 - 2006)Lakeville Water Resources Management Plan Page 3-46

Figure 3.11.8Kingsley Lake average summer (May – September) total phosphorus concentrations, 0 – 2 meters0.030.025Average Total Phosphorus (mg/L)0.020.0150.010.00501992 1994 1996 1998 2000 2002 2004 2006 2008YearAverage Total Phosphorus (0-2 m, May - Sept) Trend (1993 - 2006)Lakeville Water Resources Management Plan Page 3-47

Figure 3.11.9 Kingsley Lake average summer (June – September) Secchi Depth, 1993 – 200643.53Average Secchi Depth (m)2.521.510.501992 1994 1996 1998 2000 2002 2004 2006 2008YearAverage Secchi Depth (June - Sept) Trend (1993 - 2006) Trend (2001 - 2006)Lakeville Water Resources Management Plan Page 3-48

Figure 3.11.10Lake Marion average summer (May – September) total phosphorus concentrations, 0 – 2 meters0.10.090.08Average Total Phosphorus (mg/L)0.070.060.050.040.030.020.0101965 1970 1975 1980 1985 1990 1995 2000 2005 2010YearAverage Total Phosphorus (0-2 m, May - Sept) Trend (1969 - 2006)Lakeville Water Resources Management Plan Page 3-49

Figure 3.11.11 Lake Marion average summer (June – September) Secchi Depth, 1969 – 200632.5Average Secchi Depth (m)21.510.501965 1970 1975 1980 1985 1990 1995 2000 2005 2010YearAverage Secchi Depth (June - Sept) Trend (1969 - 2006)Lakeville Water Resources Management Plan Page 3-50

Figure 3.11.12 Valley Lake average summer (June – September) Secchi Depth, 1995 – 20062.52Average Secchi Depth (m)1.510.501994 1996 1998 2000 2002 2004 2006 2008YearAverage Secchi Depth (June - Sept) Trend (1995 - 2006)Lakeville Water Resources Management Plan Page 3-51

Figure 3.11.13Valley Lake average summer (May – September) total phosphorus concentrations, 0 – 2 meters0.120.1Average Total Phosphorus (mg/L)0.080.060.040.0201994 1996 1998 2000 2002 2004 2006 2008YearAverage Total Phosphorus (0 - 2 m, May - Sept) Trend (1995 - 2006)LakevilleWater Resources Management Plan Page 3-52

3.12 WATER QUANTITY /FLOODINGThe City of Lakeville has enforced a floodplain zoning ordinance (Floodplain Overlay District –Section 46 of the Zoning Ordinance) in conformation with Minnesota DNR requirements since 1978.This ordinance was updated in 1991. This ordinance references the floodplain as defined by theFlood Insurance Study (FIS) for the City of Lakeville published by the Federal EmergencyManagement Agency (FEMA). This FIS is described in Section 3.12.1 and presented in Figure3.12.1.The FIS, together with the City’s floodplain ordinance, allow the City to take part in the federalgovernment’s flood insurance program. Homeowners within FEMA-designated floodplains arerequired to purchase flood insurance. In some cases, homes within FEMA-designated floodplains onthe FEMA floodplain maps may actually not be in the floodplain. In order to waive the mandatoryflood insurance requirements for their homes, residents must remove their homes from the FEMAdesignatedfloodplain by obtaining Letters of Map Amendment (LOMA). The City of Lakevillefloodplain ordinance applies to those areas covered by the FIS.3.12.1 Flood Insurance StudiesThe Federal Emergency Management Agency (FEMA) completed a flood insurance study (FIS)for the City of Lakeville in 1979. In 1994, FEMA revised these maps based on the hydrologypresented in the City of Lakeville’s previous Stormwater Management Plan. The revised FISbecame effective in April of 1998. A city-wide floodplain map is included in this document asFigure 3.12.1. A more detailed FIS for the City of Lakeville may be obtained from theMinnesota DNR, City offices, or the map services center at the FEMA website(http://msc.fema.gov/).3.13 RECREATIONAL AREASThe Parks and Recreation Department of the City of Lakeville maintains a total of 53 community andneighborhood parks covering an area of more than 1,100 acres. Lakeville parks offer athletic fields,playgrounds, tennis courts, skating rinks, picnic areas, conservation areas, and nature areas. Thereare more than 60 miles of pedestrian and bike trails. Also available are cross-country ski trails,snowmobile trails, and equestrian trails. Figure 3.13.1 shows the distribution of recreational areasand open spaces in Lakeville.There are several public parks located along the shorelines of Lake Marion, Orchard Lake, and ValleyLake. These parks include three swimming beaches, and several public fishing areas. In addition,public boat access is available at Lake Marion and Orchard Lake.Lakeville Water Resources Management Plan Page 3-53

3.14 FISH AND WILDLIFE HABITATSeveral lakes within the city of Lakeville are stocked by the Minnesota DNR and contain large fishpopulations. Crystal Lake is managed by the Minnesota DNR as a pan-fish lake and is stocked withtiger muskellunge. Lee Lake has an excess number of stunted bluegill sunfish in addition to blackbullhead, black crappie, yellow perch, northern pike, and largemouth bass. All species present in LeeLake are also present in Lake Marion, with the addition of walleye and white sucker. The followingspecies are present in Orchard Lake: black bullhead, yellow bullhead, bluegill sunfish, green sunfish,hybrid sunfish, pumpkinseed sunfish, tiger muskellunge, northern pike, black crappie, largemouthbass, walleye, and yellow perch. Species similar to Orchard Lake are found in Valley Lake, with theaddition of golden shiner and white sucker. Tiger muskellunge is not found in Valley Lake. Keepingsunfish less than 5 inches (limit 20 per day) and bullheads (limit 100 per day) is encouraged in LakeMarion, Lee Lake, and Valley Lake.Sections of South Creek have been designated as trout streams by the Minnesota DNR (see Figure3.8.1). A survey in 1982 found no trout in the stream and reported the area as having marginalsuitability for trout habitat. South Creek was stocked with brown trout in 1983. In 1993, a MDNRrepresentative reported brown trout in South Creek east of Cedar Avenue.Every year, the Minnesota Department of Natural Resources conducts a trout survey along therestored stretches of South Creek on the east and west sides of Cedar Avenue in the AirlakeIndustrial area of Lakeville. The survey is conducted to obtain a population estimate and obtainbaseline data. The 2006 survey found a few large trout on the east side of Cedar Avenue and a largespawning male and female to the west of Cedar. The male was nearly 24” long with an estimatedweight of five pounds. Two rainbow trout were also counted. Each year brown trout and somerainbow trout are stocked in South Creek and several parts of the Vermillion River. The two femalerainbow trout were much larger than what would be stocked, so they were deemed to have beensuccessful in living in these waters for at least a couple of years. Several "young of the year" andmany large males and females were found during the 2006 survey. The survey results overallindicated that South Creek is successfully supporting reproducing trout.There are no county- or state-protected wildlife habitat areas within the city of Lakeville. The Cityhas established conservation easements to create an area of protection where important naturalareas have been preserved. The conservation easement protects significant features of the property,but the property remains in private ownership. The purposes of conservation easements ofteninclude preserving water quality, vegetation, and wildlife habitat.Lakeville Water Resources Management Plan Page 3-54

3.15 UNIQUE FEATURES AND SCENIC AREASThrough its Natural Heritage and Nongame Research Program, the DNR collects, manages, andinterprets information about nongame animals, native plants and plant communities. The programis closely tied with the MnDNR’s Minnesota County Biological Survey, which identifies and locatesrare natural resources. The Natural Heritage and Nongame Research Program develops andmaintains lists of the rare natural features in Minnesota, including Minnesota’s list of endangered,threatened, and special concern species; Minnesota’s list of natural communities; and importantanimal aggregation sites. This information is included in Minnesota’s Natural Heritage InformationSystem, which is maintained by the DNR, through its Natural Heritage and Nongame ResearchProgram, and can be obtained from the DNR for a fee.The MnDNR’s Minnesota County Biological Survey for Dakota County (1997) indicates two naturalcommunities with moderately significant biodiversity: a 55-acre area in Ritter Farm Park west ofLake Marion, and a 9-acre are south of North Creek near the Farmington-Lakeville border. Thenatural community in Ritter Farm Park is classified as oak woodland-brushland. This area isdescribed as dry woodlands on loess, outwash, and glacial till, with 50 to 70 percent canopy cover,and dominated by northern pin oak and white oak. Common canopy associates may include red oak,bur oak, quaking aspen, big-toothed aspen, and red elm. The shrub layer is often dense and mayinclude American hazelnut, gray dogwood, and chokecherry.The natural community south of North Creek is classified as dry prairie. These areas occur on glacialtill on slopes and hilltops. Common grasses include big bluestem, side-oats grama, porcupine grass,and Indian grass. Common forbs include sky-blue aster, bastard toad-flax, and western sunflower.The Dakota County survey shows the presence of rare animals in one location along the western edgeof the city near Murphy-Hanrehan Regional Park. The survey does not indicate the rare speciespresent; this information may be obtained through the DNR Natural Heritage and NongameResearch Program.3.16 POLLUTANT SOURCESFigure 3.16.1 shows the locations of existing and potential pollutant sources within the city ofLakeville. The sources include those sites listed in the MPCA’s Master Entity System (MES), leakingunderground storage tanks (LUSTs), existing above-ground and underground storage tanks, andhazardous waste generators. Many of these sites have been cleaned up or are in the clean-upprocess. Information regarding specific sites should be directed to Dakota County or the MPCA.The City of Lakeville has established best management practices (BMPs) designed to educate citizensabout the consequences of non-point source pollution and illicit discharges. The City sponsors alocal hazardous waste drop off event once a year at the City’s Central Maintenance Facility.Lakeville Water Resources Management Plan Page 3-55

Crystal LakeValley LakeLee LakeKingsley LakeNorth CreekOrchard LakeBarr Footer: Date: 5/14/2008 11:32:44 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_1_1_2006 Landuse.mxd User: arm2Lake MarionSouth CreekNorth Branch of South CreekEast Branch of South CreekSouth Branch of South CreekFigure 3.1.12006 LAND USECity of LakevilleWater Resources Management PlanMunicipal BoundaryStreamsParcel Boundary2006 Land Use*AgricultureAirportCommercialForestGrasslandMulti-Family ResidentialHighwayIndustrialInstitutionalRural ResidentialSingle Family ResidentialWater*Data Sources include 2005 Metropolitan Council Landuse GIS data, USGSNational Landcover Database (1992), Dakota County Parcel Data, 2006 aerialphotography, City Wetland Inventory, and development information from the Cityof Lakeville Engineering and Planning staff.Other data sources include: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31North CreekBarr Footer: Date: 5/14/2008 11:35:30 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_1_2_2020 Landuse.mxd User: arm2Orchard LakeKENWOOD TRL4567 23185TH ST W§¨¦ 35Lake Marion4567 50456 70IPAVA AVE4567 9DODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.1.22020 LAND USECity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreams2020 Land Use*AgricultureAirportCommercialForestOther data sources include: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500MetersGrasslandMulti-Family ResidentialHighwayIndustrialInstitutionalRural ResidentialSingle Family ResidentialWater*Data Sources include the City of Lakeville 2020 Comprehensive Landuse Plan,Lakeville wetland GIS data, USGS National Land Cover Database (NLCD)and information from City of Lakeville Engineering and Planning staff.

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31North CreekBarr Footer: Date: 5/14/2008 11:39:49 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_3_1 Elevation.mxd User: arm2Orchard Lake4567 23185TH ST W§¨¦ 35 4567 9Lake Marion4567 50456 70IPAVA AVEDODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.3.1ELEVATIONCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreamsLakes10ft Contours2ft ContoursI3,500 1,750 0 3,500Feet750 375 0 750 1,500MetersElevationHigh : 1188.92Low : 881.466Data Sources: City of Lakeville, Dakota County, Minnesota DNR, MnDOT.Imagery Source: Aerials Express, 2006.

Crystal LakeBarr Footer: Date: 5/14/2008 11:41:47 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_4_1 Stormwater Districts.mxd User: arm2Kingsley LakeOrchard LakeLake Marion Sormwater DistrictValley Lake162ND ST WLee LakeCrystal Lake Stormwater DistrictOrchard Lake Stormwater District§¨¦ 35Lake Marion456 70185TH ST W4567 50IPAVA AVESouth Creek Stormwater DistrictNorth Branch of South CreekEast Branch of South CreekSouth Creek215TH ST WSouth Branch of South CreekNorth Creek160TH ST WNorth Creek Stormwater District4567 23Farmington Stormwater District190TH ST W4567 9DODD BLVD202ND ST WCEDAR AVE4567 31PILOT KNOB RDFigure 3.4.1STORMWATER DISTRICTSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStormwater District BoundaryStreamsLakesBlack Dog WatershedVermillion River WatershedData Sources: City of Lakeville, Minnesota DNR, MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31North CreekBarr Footer: Date: 5/14/2008 11:46:30 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_5_1 Soils.mxd User: arm2Orchard Lake4567 23185TH ST W§¨¦ 35 4567 9Lake Marion4567 50456 70IPAVA AVEDODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.5.1SOIL TYPESCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreamsLakesHydrologic SoilsAA/DData Sources: NRCS, City of Lakeville, Minnesota DNR, MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500MetersBB/DCC/DDUrban/No Data

Crystal LakeBarr Footer: Date: 5/6/2008 1:58:03 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Figure_3_6_1 Bedrock Geology.mxd User: arm2!(!( !(!(!( !(!(!(GF !(!( !(!( !(!(!( Orchard LakeXW!( !(XW !( XW!(4567 23!(!(160TH ST W!(!(!(!(!(Valley Lake!( !( !(!(!(!(!(!(!( 162ND ST W ^_!(!(!(!( !(!( !(!(!( !(Lee Lake!(XW#*!( GFKingsley Lake !(!(!(#*!(GF!(!(!( !(!( !( !(!( !(!(!(#*!(#* !(!(!(GF!(!( !(XWGF!(§¨¦ 35 !(!(!(!(!(190TH !( ST W!( !(!(!(XW!( !(XWXW!( !( !(!(XW!(XW")185TH ST WXWXWXW !(!(!(!(!(!(!(!(!(!( !(!($8!(!(456 70!(!(!(!(Lake Marion4567 50IPAVA AVE!( !(!( !( !(!(DODD BLVD!(!(GFSouth Creek!(215TH ST W4567 9!(!( !(!(!(!(!(202ND ST WNorth Branch of South CreekEast Branch of South Creek!(!(!(!(")South Branch of South Creek!(CEDAR AVENorth Creek4567 31PILOT KNOB RDFigure 3.6.1BEDROCK GEOLOGYCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreamsLakesBedrock GeologyPrairie du ChienSt. Peter SandstonePlatteville Glenwood FormationData Sources: Dakota County, City of Lakeville,MN DNR, MnDOT, Geologic Atlas of Dakota County.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500MetersWells by Use( Domestic* Commercial) Municipal1 IndustrialYW Sealed_ IrrigationF UnknownWells by Aquifer Utilized' Prairie du Chien Dolomite' St. Peter Sandstone' Multiple Aquifer' Unconsolidated Sediments' Unknown

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31North CreekBarr Footer: Date: 5/14/2008 11:50:49 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_6_2 Surficial Geology.mxd User: arm2Orchard Lake4567 23185TH ST W§¨¦ 35 4567 9Lake Marion4567 50456 70IPAVA AVEDODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.6.2SURFICIAL GEOLOGYCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreamsLakesSurface Geology Type"Old Gray" TillOutwash; SuperiorIce-contact; SuperiorDes Moines Till over "Old Gray"Ice-contact; Des Moines/SuperiorMixed Till; Des Moines/SuperiorMixed Outwash; DesMoines/SuperiorOrganic DepositWater BodyData Sources: City of Lakeville, MN DNR, MnDOT, Geologic Atlas of Dakota County.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake19-27 P19-383 W19-32 P19-384 WLee Lake19-29 P19-360 W19-361 W162ND ST WValley Lake19-348 W160TH ST W19-30 PKingsley Lake19-349 WBarr Footer: Date: 5/14/2008 11:52:36 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_8_1 Public Waters.mxd User: arm219-362 W19-363 WOrchard Lake19-31 P19-386 W19-365 W19-366 W19-387 W19-390 W19-388 W19-391 W19-389 W19-393 W19-397 P19-399 P19-398 P19-401 W19-400 W19-367 W19-371 W4567 2319-371 W19-369 W19-368 W19-370 W19-394 W19-372 W19-377 W185TH ST W19-395 W19-373 W19-374 W19-375 W4567 9§¨¦ 35Lake Marion 19-378 W19-26 P19-404 W202ND ST W19-405 W19-406 W19-407 W19-396 W19-403 W19-402 W456 704567 50IPAVA AVEDODD BLVDCEDAR AVENorth Branch of South CreekSouth Creek190TH ST WEast Branch of South Creek19-410 W19-408 W215TH ST W19-411 W19-409 W19-413 W19-412 WSouth Branch of South Creek4567 31PILOT KNOB RD19-350 WFigure 3.8.1PUBLIC WATERSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryMinnesota Designated Trout StreamsPublic WatersData Sources: City of Lakeville, Minnesota DNR, MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31Orchard LakeBarr Footer: Date: 5/14/2008 11:53:46 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_9_1 Wetlands.mxd User: arm24567 23185TH ST W§¨¦ 35 4567 9456 70Lake Marion4567 50IPAVA AVEDODD BLVDCEDAR AVE202ND ST W215TH ST W190TH ST WPILOT KNOB RDFigure 3.9.1WETLANDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryWetlands - 2003 InventoryOther WetlandsParcel BoundaryData Sources: City of Lakeville, Dakota CountySoil and Water, Minnesota DNR, MnDOT,City of Lakeville Wetland Management Plan (2003).Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST WValley Lake162ND ST WKingsley LakeLee LakeCrystal Lake Stormwater DistrictNorth Creek Stormwater DistrictNorth Creek4567 31Barr Footer: Date: 5/14/2008 11:55:47 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_10_1 Surface Water System.mxd User: arm2Orchard LakeOrchard Lake Stormwater DistrictLake Marion Stormwater DistrictLake MarionSouth Creek Stormwater DistrictFarmington Stormwater District4567 23185TH ST W§¨¦ 35456 704567 50IPAVA AVE4567 9DODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.10.1SURFACE WATER SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryStormwater District BoundaryMinnesota Designated Trout StreamsOther StreamsLakesPublic WatersParcel BoundaryData Sources: City of Lakeville, MN DNR.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31North CreekBarr Footer: Date: 5/14/2008 12:05:40 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_12_1 Floodplain.mxd User: arm2Orchard Lake4567 23185TH ST W§¨¦ 35 4567 9Lake Marion4567 50456 70IPAVA AVEDODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.12.1FLOOD INSURANCE STUDYCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreamsFloodway*100 Year Floodplain*500 Year Floodplain*Approximate 100 Year Floodplain*Data Sources: City of Lakeville, Dakota County, MN DNR, MnDOT.*Digital Flood Insurance Rate Map (DFIRM) data is preliminary andnot yet effective.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31North CreekBarr Footer: Date: 5/14/2008 12:07:56 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_13_1 Recreational Areas.mxd User: arm2Orchard Lake4567 23185TH ST W§¨¦ 35 4567 9Lake Marion4567 50456 70IPAVA AVEDODD BLVDCEDAR AVENorth Branch of South Creek202ND ST WEast Branch of South Creek190TH ST WSouth Creek215TH ST WSouth Branch of South CreekPILOT KNOB RDFigure 3.13.1RECREATIONAL AREASAND OPEN SPACESCity of LakevilleWater Resources Management PlanMunicipal BoundaryStreamsLakesParcel BoundaryRecreational Areas & Open SpacesData Sources: City of Lakeville, MnDOT, Minnesota DNR.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Crystal Lake160TH ST W162ND ST WValley LakeBarr Footer: Date: 5/14/2008 12:14:35 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section3\Figure_3_16_1 Pollutant Sources.mxd User: arm2#*Kingsley LakeOrchard Lake!(!(!(!(!(!(!(!(!( !( !(#*Lee Lake#*#*!(!(!(!(!(!(!(!(!( !( !(!(!(!( !(!(!(!(!( !(185TH ST W !(!(4567 9Lake Marion!(!(4567 50!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(#*§¨¦ 35 4567 23456 70IPAVA AVEDODD BLVD!(#*!(#* !( #*#*#*!(South Creek!(215TH ST W!(#*!(202ND ST WNorth Branch of South Creek#*!(!(#*!(!( !(!(!(!(!( !(!(!( !(#*!( !(#*#*#*East Branch of South Creek!( South Branch of South Creek#*CEDAR AVE190TH ST WNorth Creek4567 31PILOT KNOB RD!(Figure 3.16.1POLLUTANT SOURCESCity of LakevilleWater Resources Management Plan!( Spills!( Existing Tanks#* MPCA M.E.S. Site!( Hazardous Waste Generators!( LUST SitesMunicipal BoundaryParcel BoundaryStreamsLakesData Sources: City of Lakeville, MPCA, MN DNR, MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Section 4.0 Stormwater System District AnalysisThe 1995 Lakeville Stormwater Management Plan included the development of a citywidehydrologic model and water quality modeling for the watersheds. The program presented here isbased on that modeling work done in 1994. Since that time development and other changes haveoccurred requiring update of this modeling. Further, the Vermillion River Watershed JointPowers Organization (VRWJPO) is currently developing an updated watershed-wide model uponwhich to guide community discharge rate restrictions.In response to these changes, the City of Lakeville will begin the development of updatedhydrologic and water quality models for the city in 2008. These updated models will account forchanges that have occurred in the system over the last 13 years and will conform to the VRWJPOhydrologic model results and any resulting flow or volume restrictions.The updated modeling will likely result in some changes in pond locations and volumes as wellas changes for pipe sizing. As a result, this program will be updated based on the updatedmodel. This Water Resources Management Plan will then be updated to include the new designprogram. In the interim, this section will continue to be the basis for design of the city’s systemneeds.The City recently completed the Lakeville Ms4 Loading Assessment and Non DegradationReport, included as Appendix D. This report also provides a general citywide water qualitymodel and analyses.The City will be updating both its hydrologic and water quality modeling as part of theimplementation of this plan (Section 7).4.1 CITY OF LAKEVILLE PIPE NETWORKFigures 4.2.1 – 4.7.2 present the city of Lakeville’s storm sewer network and other details.The following sections provide details for subwatershed districts with special issues.4.2 CRYSTAL LAKE DISTRICTThe Crystal Lake District has an area of approximately 1,420 acres in the city of Lakeville alongthe northern boundary of the city. It extends from Kenwood Trail on the west to HighviewAvenue on the east, between 175th Street and the boundary with the City of Burnsville. Themajority of Crystal Lake and the watershed contributing runoff to Crystal Lake lie within the cityLakeville Water Resources Management Plan Page 4-1

of Burnsville in the Black Dog Watershed Management Organization (WMO). Lakeville is amember of this Joint Powers Organization. Outflow from Crystal Lake flows to the MinnesotaRiver via Earley Lake and Sunset Pond.The City of Lakeville will begin the development of updated hydrologic and water quality modelsfor the city in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results and anyresulting flow or volume restrictions. The updated modeling will likely result in some changes inpond locations and volumes as well as changes for pipe sizing. As a result, this program will beupdated based on the updated model. This Water Resources Management Plan will then beupdated to include the new design program. In the interim, this section will continue to be thebasis for design of the city’s system needs.The watershed divides within the city of Lakeville in the Crystal Lake District are shown onFigure 4.2.1. Further details of the drainage system are shown on Figure 4.2.2.This entire district is tributary to Crystal Lake. Runoff from approximately 285 acres within thedistrict flows into Lee Lake which is currently landlocked. The city recently constructed a gatedoutlet to direct outflow from the lake to the east under Interstate 35 (I-35).The drainage system for the Crystal Lake District watershed was analyzed in two separatesections, the eastern and western sections of the watershed. Runoff from the western CrystalLake District flows to Crystal Lake through two locations:the pond in Oak Shores Park, north of 162nd Street West, between Jamaica Avenue andJoplin Avenue (CL-2-1)the drainage swale in Oak Shores Park just east of Jamaica Avenue, between 161st StreetWest and Oak Shore DriveUntil 1993, runoff from the eastern Crystal Lake District flowed to Crystal Lake through theexisting storm sewer located just south of County Road 46 and east of Illinois Avenue (inSubwatershed CL-31), extending north along Lac Lavon Drive through the city of Burnsville.Since 1993, the flow has been routed along County Road 46 to the Bluebill Bay Pond as part ofthe reconstruction of County Road 46. The ponding basin in Bluebill Bay Estates is located inSubwatershed CL-21, south of Bluebill Bay Road and west of Inglewood Drive.Runoff from approximately 138 acres in the Buck Hill development in the city of Burnsville flowsthrough the city of Lakeville, Crystal Lake District watershed into Crystal Lake.Within the city of Lakeville, nearly all of the Crystal Lake District is developed. Most of thewatershed is single family residential. The land adjacent to Interstate 35 is primarilycommercial.Lakeville Water Resources Management Plan Page 4-2

4.2.1 PONDNET Modeling of Crystal Lake DistrictBecause of the large area of the lake watershed that lies outside the city of Lakeville,modeling of the entire watershed was beyond the scope of this plan. This has beenundertaken by the Black Dog WMO.Runoff from the city of Lakeville currently enters Crystal Lake from three different locations:Oak Shores Park pond, Oak Shores drainage channel and Bluebill Bay Pond. The majority ofthe drainage that flows through the Oak Shores drainage channel was rerouted into the OakShores Park pond with the reconstruction of County Road 46 in the summer of 1994. Forproposed conditions, runoff from the city will enter Crystal Lake through the Oak ShoresPark and Bluebill Bay ponds. The PONDNET model estimates of the existing and proposedaverage surface inflow volume, phosphorus loading, average phosphorus concentration andpercent of total phosphorus removal for the flow into Crystal Lake are shown in Table 4.2.1.The computed existing phosphorus concentrations into Crystal Lake are higher than hasbeen observed in Crystal Lake, which is approximately 44 ppb (data from MPCA website).The PONDNET model was developed for networks of ponds, and may not accurately modelthe effect of a large lake such as Crystal Lake. Information on the entire Crystal Lakewatershed must be compiled to accurately model the lake concentrations.The proposed development in the Crystal Lake District is mainly low-density residential,with a large commercial area adjacent to Interstate 35. It was assumed that all wetlandsshown on the National Wetlands Inventory will be preserved for proposed conditions. Allstormwater ponds were assumed to be constructed with an average of at least 3 feet of waterquality storage (i.e., dead storage) below the runout elevation.4.2.2 PONDNET Modeling of Lee Lake DistrictThe water quality modeling results presented here were completed in 1993. The City ofLakeville will begin the development of updated hydrologic and water quality models for thecity in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results.This Water Resources Management Plan will be updated to include the new model results.In the interim, this section will continue to be the basis for design of the city’s system needs.The City recently completed the Lakeville Ms4 Loading Assessment and Non DegradationReport, included as Appendix D. This report also provides a general citywide water qualitymodel and analyses.The existing and proposed levels predicted by the PONDNET model are listed inTable 4.2.2. The model shows an existing average annual phosphorus concentration of84 ppb in Lee Lake. This value is approximately the same as that observed in the earlysummer of 1990 (70 ppb - 80 ppb).Lakeville Water Resources Management Plan Page 4-3

4.2.3 Flood ProtectionFor each subwatershed and storage pond, peak runoff rates, flood levels, flood dischargesand storage volumes were calculated using the HEC-1 model as described in Appendix B.The results of the modeling are shown in the tables at the end of this section. Information isdescribed as follows:Table 4.2.4Table 4.2.5Table 4.2.6Table 4.2.7Table 4.2.8Table 4.2.9Table 4.2.10Table 4.2.11Table 4.2.12Existing Conditions—Hydraulic and hydrologicparameters (subwatershed data)Existing Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Existing Conditions—Peak discharges and elevations(flood levels and outflows from ponds)East - Proposed Conditions—Hydraulic and hydrologicparameters (subwatershed data)East - Proposed Conditions—Critical events andcorresponding runoff (peak flow rates from watersheds andponds)East - Proposed Conditions—Peak discharges andelevations (Flood levels and outflows from ponds)West - Proposed Case 6—Hydraulic and hydrologicparameters (subwatershed data)West - Proposed Case 6—Critical events andcorresponding runoff (peak flow rates from watersheds andponds)West - Proposed Case 6—Peak discharges and elevations(flood levels and outflows from ponds)No monitoring data was available at the inflow locations for calibration of the HEC-1 model.The 100-year peak flow rates computed in the HEC-1 model were compared with the peakflow rates computed using the U.S. Geological Survey (USGS) regression method (Jacques &Lorenz, 1987). A comparison of existing conditions is shown in Table 4.2.3.The 100-year peak flow rates predicted using the USGS regression method are consistentlyhigher than those predicted in the HEC-1 model. The peak flow rates into the mostdownstream pond before entering a lake compare closer to the regression values. This can beattributed to the storm sewer system and network of ponds currently in place in the district.Lakeville Water Resources Management Plan Page 4-4

4.2.4 Subwatershed DescriptionsThe subwatersheds described in this section have unique characteristics or significantalterations from existing to proposed conditions.Crystal Lake District WestSix separate cases were analyzed for the western Crystal Lake subwatersheds under futureconditions. The cases were examined to find an acceptable way to lower the predicted floodlevels of Ponds CL-2-1, CL-3-1, and CL-5-1. The recommended alternative (Case 6) ispresented in the plan as the future condition. Information on the other alternatives isavailable from the City if necessary.CL-1 - Crystal Lake: The majority of Crystal Lake and the subwatershed draining to CrystalLake, lie within the city of Burnsville. A complete hydrologic analysis of Crystal Lake was notcompleted as a part of this plan.CL-2: The pond in this watershed (CL-2-1) is located in Oak Shores Park. The pond consistsof three connected ponding basins, which act as one pond during high water levels.Increased development and additional drainage areas from upstream subwatershedsincreases the proposed 100-year flood level of Pond CL-2-1. This flood level was decreasedby increasing the storage volume in upstream ponds and by lowering the two connectingpipes in CL-2-1 to elevation 938.2.CL-3: Subwatershed CL-3 is located within the Crystal Ridge Estates development. Theexisting outlet from Pond CL-3-1 is 2 48-inch RCPs that discharge under County Road 46 toPond CL-2-1.For proposed conditions, the storage volume of Pond CL-3-1 was assumed to decrease withthe construction of the new County Road 46. The proposed increase in developmentupstream is compensated for by the additional storage planned in upstream subwatersheds.A second pond (CL-3-2) was developed within this watershed (CL-3A) for proposedconditions to prevent flooding downstream.CL-4: A storage basin in Subwatershed CL-4A (Pond CL-4-1) contains water only duringlarger flooding events, when a portion of the park field is inundated. For proposedconditions, the drainage divides were assumed to remain approximately the same as existingconditions.CL-5: The flood levels predicted for Pond CL-5-1 are very close to the level of the adjacentlow house, which is approximately at elevation 950.5. The available storage volume includesstorage in the existing marsh located southwest of the Jewel Avenue cul-de-sac.For proposed conditions, the storage volume of Pond CL-5-1 was increased by expanding theexisting marsh in the western portion of the pond.Lakeville Water Resources Management Plan Page 4-5

CL-6: There is no existing stormwater detention pond in this subwatershed. Runoff iscollected in the existing storm sewer system and routed north to Pond CL-5-1. The proposedland use for this subwatershed was revised to low density residential, as reflected in theRolling Oaks South Plat 6 plans.CL-7: Subwatershed CL-7 borders Interstate 35 on the west. To provide a factor of safetyand eliminate flooding of downstream ponds, the overall imperviousness for the commercialareas in this subwatershed are restricted to 70 percent rather than 80 percent as is requiredin remainder of the city. The City has restricted imperviousness on new developments since1994.To analyze the drainage for future conditions, the subwatershed was subdivided into threeseparate areas: CL-7A, CL-7B and CL-7C. Two ponds, CL-7-1 and CL-7-2, were developedwithin this subwatershed for future conditions. Plans for the County Road 46 andInterstate 35 interchange were used for Subwatersheds CL-7A1 and CL-7A2.CL-8: Approximately 130 acres of this subwatershed is located within the city of Burnsville.Calculations indicate that the 100-year flood level of Pond CL-8-1 will overtop the existingoverflow berm and cause water to flow overland to an existing 43-inch by 27-inch CMP archunder Kenyon Avenue.To analyze the drainage for future conditions, the subwatershed was subdivided into twoseparate areas: CL-8A and CL-8B (using plans for the County Road 46 and Interstate 35interchange). According to the interchange plans, Pond CL-8-1 was relocated between theproposed frontage road and the northwest loop. Pond CL-8-2 was added in the northwestloop of the proposed interchange.CL-9, CL-10 and CL-11: To provide a factor of safety and eliminate flooding of downstreamponds, the overall imperviousness for the high density residential area in thesesubwatersheds was restricted to 50 percent and the imperviousness for the commercial areaswas restricted to 70 percent. The City has restricted imperviousness on new developmentssince 1994.CL-12 - Lee Lake: Lee Lake (CL-12-1) has an existing gated outlet that was installed in 1993.The historical water level of the lake has varied, but the City considers the long-term normalwater level to be elevation 946.1. Using this as a starting elevation for the analysis, theexisting 100-year flood level is elevation 953.1 (assuming the lake is landlocked). However,as with any landlocked lake, this will vary and can increase. The low structure adjacent tothe lake is at elevation 953.98.For proposed conditions, the recently installed 36-inch RCP outlet was assumed to be atelevation 947.0. To prevent flooding of downstream ponds, the outlet is equipped with aLakeville Water Resources Management Plan Page 4-6

gate. It was assumed that the gate will normally be closed and that the process of openingthe gate will take at least several hours. This means that all short duration storms (less thanone day in duration) will have to be stored in Lee Lake.The gate was assumed to remain closed when downstream ponds are at or near flood levels.For storms with durations from one to four days (the approximate critical duration fordownstream ponds) the gate will also remain closed and the runoff will have to be stored.For very long duration events (10-day and 30-day), it is assumed that the gate will be openedsoon after the commencement of the event and will remain open until Lee Lake reaches itsnormal level.Based on these assumptions, the proposed 100-year flood level of Lee Lake was lowered from953.1 to approximately 951.9 feet. This occurs with the complete storage of the four-daystorm. It should be recognized that this flood level is very dependent on the actual operationof the gate. The 100-year peak discharge rate assumes that the downstream Pond CL-5-1 isat elevation 945.5.CL-14: This subwatershed is currently landlocked. The storm sewer system proposed withthe reconstruction of County Road 46 will route runoff from this subwatershed to the eastinto Pond CL-8-1.CL-15: There is an existing low area (Pond CL-15-1) at the 24-inch RCP inlet under 162ndStreet West. Runoff from this subwatershed flows north under 162nd Street West through adrainage channel and storm sewer system just east of Jamaica Avenue through the OakShores development to Crystal Lake. The 18-inch RCP under 161st Street is restrictive of thechannel flow, and 161st Street is overtopped at elevation 961.0. When the Pond CL-15-1reaches approximate elevation 965, flow is diverted south of 162nd Street to the west througha drainage ditch to Pond CL-3-1.To prevent direct discharge to Crystal Lake for proposed conditions, the outlet under CountyRoad 46 was eliminated with the construction of the County Road 46 storm sewer system. Inthe summer of 1994 all flows were directed through the proposed storm sewer to Pond CL-3-1. The available storage volume in Pond CL-15-1 was increased to prevent flooding indownstream ponds (approximately 2-acre pond area).CL-16: A 2-acre pond (CL-16-1) was assumed to be constructed for proposed conditions, todecrease the peak flow rate downstream. Outflow from Pond CL-16-1 was assumed to berouted in the recently constructed storm sewer along County Road 46 to Pond CL-3-1.CL-17: To decrease the 100-year peak discharge for proposed conditions, a 2-acre pond wasassumed to be constructed south of 165th Street (CL-17-2).CL-18: The proposed storage volume of Pond CL-18-1 was obtained from theLakeville Water Resources Management Plan Page 4-7

Lynwood/Vivant development plans.CL-19: The proposed storage volume of Pond CL-19-1 was obtained from theLynwood/Vivant development plans.Crystal Lake District EastCL-25: Runoff from upstream subwatersheds enters CL-25, where flow is then directedthrough an existing 48-inch RCP under County Road 46 to Pond CL-21-1. The existingconditions 100-year flood level of Pond CL-25-1 overtops the existing County Road 46 byapproximately 1.8 feet.A majority of the area in this subwatershed is within the new Crystal Lake Golf Clubdevelopment. Plans for this development were used to determine the proposed conditionsdrainage and ponding areas. Discharge from Pond CL-25-1 flows into the storm sewer underCounty Road 46 and into Pond CL-21-1.CL-26: This subwatershed consists of mainly agricultural land, and includes the Crystal LakeElementary School. There is no existing stormwater detention pond in this subwatershed,and excess runoff flows in the County Road 46 drainage ditch to CL-25.The proposed land use in this watershed consists of commercial, high-density residential andschool zones. A one-half acre pond (CL-26-1) was assumed to be constructed for proposedconditions to reduce the 100-year peak flow rate. The portion currently zoned high-densityresidential (CL-26A) may be re-zoned to low-density residential (located southwest of Ipavaand 162nd Street). If the area is re-zoned as low density residential, Pond CL-26-1 is notrequired. This drainage plan contains information for the two alternatives.It is assumed that after reconstruction of County Road 46, runoff from CL-26 will flow to thenortheast section of the subwatershed and enter the 48-inch RCP under County Road 46 toPond CL-21-1.CL-27: Drainage from this subwatershed flows to Subwatershed CL-25 through a drainageswale. There is no existing stormwater detention pond in this subwatershed. This entiresubwatershed is included in the proposed Crystal Lake Golf Club development. Preliminaryplans for this development were used to determine the required drainage facilities.CL-30: This entire subwatershed is included in Crystal Lake Golf Club development forproposed conditions. Preliminary plans for this development were used to determine thedrainage area.CL-31: Prior to 1992, runoff from upstream subwatersheds entered CL-31 and was directedthrough a 15-inch RCP under County Road 46 to Burnsville, and flowed directly into CrystalLake. The existing 100-year flood level of CL-31-1 reflects this prior system, and showsLakeville Water Resources Management Plan Page 4-8

County Road 46 overtopped by approximately 0.4 feet. However, this culvert was eliminatedin 1994 with the reconstruction of County Road 46 and drainage was diverted to Pond CL-21-1, as reflected in the proposed conditions analysis.This entire subwatershed is included in the Crystal Lake Golf Club development. Preliminaryplans for this development were used to determine the required drainage facilities.CL-32: This entire subwatershed is located within the Hypointe Crossing development.Prior to 1992, outflow from Pond CL-32-1 flowed in the County Road 46 drainage ditch toCL-31, as reflected in the existing conditions analysis. For proposed conditions, the outflowfrom the pond was routed in the recently constructed storm sewer along County Road 46 tothe 48-inch RCP inlet under County Road 46, to Pond CL-21-1.CL-33: This entire subwatershed is located within the Hypointe Crossing development.Outflow from the pond flows through an existing storm sewer to Pond CL-32-1. Forproposed conditions, decreased drainage area from upstream subwatersheds decreases theproposed 100-year flood level on Pond CL-33-1.CL-34: Until 1992, runoff from this subwatershed flowed along the County Road 46 drainageditch to Pond CL-33-1, as reflected in the existing conditions analysis. For proposedconditions, drainage from CL-34 was routed through the storm sewer along County Road 46to Pond CL-32-1 which was subsequently constructed in 1994.4.3 ORCHARD LAKE DISTRICTThe Orchard Lake District has its south end approximately at 185th Street West and extendsnorth to the boundary with the city of Burnsville, and westerly from Ipava Avenue to theboundary with Credit River Township. The district lies within the Credit River Watershed,which is managed by the BDWMO. Drainage from the Orchard Lake District flows into CreditRiver, which discharges to the Minnesota River. Kingsley and Orchard Lakes are the major lakesin the district and lie entirely within the boundaries of the city of Lakeville. Two smaller lakes,Horseshoe and Goose Lakes, are also located in this district. Horseshoe Lake is located on theboundary with the city of Burnsville, and outflow drains north.The City of Lakeville will begin the development of updated hydrologic and water qualitymodels for the city in 2008. These updated models will account for changes that haveoccurred in the system over the last 13 years and will conform to the VRWJPO hydrologicmodel results and any resulting flow or volume restrictions. The updated modeling willlikely result in some changes in pond locations and volumes as well as changes for pipesizing. As a result, this program will be updated based on the updated model. This WaterResources Management Plan will then be updated to include the new design program. Inthe interim, this section will continue to be the basis for design of the city’s system needs.Lakeville Water Resources Management Plan Page 4-9

The watershed divides of the Orchard Lake District are shown on Figure 4.3.1. More detail onthe drainage system is shown on Figure 4.3.2.Most of this district is tributary to Orchard Lake, the largest surface water feature in the district.The outlet from the lake is to the west into Credit River Township through Murphy HanrehanPark Reserve. Within the city of Lakeville, an area of approximately 2,087 acres is tributary toOrchard Lake. Part of Credit River Township (roughly 173 acres) is also tributary to OrchardLake and runoff from this area flows through Lakeville in the southwestern portion of thewatershed.Approximately 424 acres analyzed as part of this district do not drain to Orchard Lake, but northand west to other municipalities. Runoff from approximately 200 acres within this district flowsnorth into the city of Burnsville. Runoff from approximately 224 acres within the district flowswest into the Credit River Township.The Orchard Lake District is largely developed with residential areas. Some commercial areasoccupy the land in close proximity to Interstate 35. Remaining areas consist of mainly forestareas and public parks. The landforms in the northwestern part of Lakeville are nearly level tovery steep and are comprised of unconsolidated clay, sand and gravel deposited as glacialmoraines.4.3.1 PONDNET Modeling of Orchard Lake DistrictThe water quality modeling results presented here were completed in 1993. The City ofLakeville will begin the development of updated hydrologic and water quality models forthe city in 2008. These updated models will account for changes that have occurred inthe system over the last 13 years and will conform to the VRWJPO hydrologic modelresults. This Water Resources Management Plan will be updated to include the newmodel results. In the interim, this section will continue to be the basis for design of thecity’s system needs. The City recently completed the Lakeville Ms4 Loading Assessmentand Non Degradation Report, included as Appendix D. This report also provides ageneral citywide water quality model and analyses.For Orchard Lake, the existing and proposed levels predicted by the PONDNET model areshown in Table 4.3.1. The PONDNET model shows a current average annual phosphorusconcentration of 61 ppb in Orchard Lake. This value is higher than has been observed at thelake, which is approximately 34 ppb (data from MPCA website). The PONDNET model wasdeveloped for networks of ponds, and may not accurately model the effect of a large lake suchas Orchard Lake.Consequently, several other phosphorus mass balance lake models were used to calibrate theresults of the PONDNET model to the observed total phosphorus concentrations in OrchardLake. The models included: Canfield and Bachman (1981), Dillon and Kirchner (1975), andLakeville Water Resources Management Plan Page 4-10

Larson and Mercier (1976). Annual phosphorus and hydrologic loading, and lake basincharacteristics from the PONDNET model were used in the mass balance models. Using thethree mass-balance models, the calculated phosphorus concentration in the lake variedbetween 6 to 55 ppb (compared to the observed concentration of 34 µg/L), much closer thanthe PONDNET prediction.The proposed development in the Orchard Lake District is primarily a continuation of lowdensity residential, with commercial areas adjacent to Interstate 35. The predicted totalphosphorus load in the inflow to Orchard Lake rises by approximately 300 percent underproposed conditions while the amount of surface water runoff that flows into Orchard Lakeincreases by approximately 500 percent. This prediction assumes that all wetlands shown onthe National Wetlands Inventory map will be preserved for proposed conditions and that allstormwater ponds will be constructed with an average of at least 3 feet of water qualitystorage (i.e., dead storage) below the runout elevation.Using the PONDNET estimates of phosphorus and hydraulic load after full development,three of the four lake phosphorus mass balance models predict an increase of over200 percent in the phosphorus concentration of Orchard Lake. Based on publishedrelationships between Secchi disc transparency and phosphorus concentrations, this changewould result in a reduction in mean Secchi disc transparency from 2.0 meters to 1.5 meters.Algae blooms would be more intense in mid to late summer. Water quality would be morecomparable to the present water quality of Lake Marion.The predicted change in Orchard Lake water quality would be very gradual, and would bemasked by the natural year-to-year variations in water quality caused by other factors, suchas weather and climate. If correct, this predicted degradation in water quality wouldcorroborate the statistical finding of a slight decline in water quality in recent years.On the other hand, it should be emphasized that this prediction contains a great deal ofuncertainty. Several major factors that determine the water quality of a lake are totallyunknown and were not included in the model. These include:groundwater inflow volumephosphorus content of the groundwaterbottom loading from sedimentsloading from sediments in Brackett's Crossing Golf CourseThe model uncertainty is also due to the fact that the actual quantity and quality of runofffrom the watershed was estimated and has not been measured. Therefore, the predictedchanges may not actually occur, or may be more severe than predicted.Lakeville Water Resources Management Plan Page 4-11

peak flow rate.4.3.3 Subwatershed DescriptionsFor proposed conditions, runoff from Credit River Township that flows into thesouthwestern subwatersheds is assumed to remain at the existing flow rates. Thesubwatersheds described in this section have unique characteristics or significant alterationsfrom existing to proposed conditions.OL-1A (Orchard Lake): The outlet for Orchard Lake is located at Orchard Lake Beach on thewest side of the lake. The control for Orchard Lake is a 17-foot concrete weir structure atapproximate elevation 976.7. Flow out of Orchard Lake is restricted by a 2-foot by 7-footconcrete box at elevation 976.1, located just downstream of the concrete weir. The MDNRhas determined the OHW of Orchard Lake to be elevation 977.6. City building permitsrequire the low floor to be at or above elevation 980.6 (3 feet above the OHW).The 100-year flood level on the lake is elevation 978.4 (1.7 feet above the weir) for existingconditions, with a 100-year peak discharge of 65 cfs. For proposed conditions, the flood levelis elevation 978.9 (2.2 feet above the weir), for the critical event (4-day rainfall) the 100-yearpeak discharge is 86 cfs. This result is based on full development. Currently, portions of thiswatershed are outside the 2030 urban service area for sanitary sewer and so the minimumlot size for new residential development in this area is 10 acres and it is expected that fullurban development is many years away.It is the policy of the BDWMO to require that post-development discharges be no greaterthan existing discharges. To decrease the 100-year peak discharge to existing conditions, theexisting box culvert may need to be restricted prior to ultimate development of thewatershed. The 100-year flood level would then be raised to elevation 979.1 (2.4 feet abovethe weir), with a 100-year peak discharge of 61 cfs.For the critical event 4-day rainfall, ponding which empties in 24 hours may not fullymitigate critical event flows. However, the City has installed additional detention in thelake's watershed, and as part of the implementation of this WRMP will implement a citywide0.5 inch infiltration standard. Another major component of the implementation of thisWRMP will be to develop a city-wide hydrologic/hydraulic model (Project S-2 in Table 7.2 ofthe Implementation Program). This model will include updated pond conditions and willexamine the impact from the application of a 0.5 inch infiltration requirement for newdevelopment. The City will use the results of the updated model to meet the BDWMO 65 cfsthreshold for Orchard Lake. The City will then implement the rate control requirements on aproject-by-project basis, and evaluate the 10-year and 100-year event rate controls.OL-1B: Historic water levels for Pond OL-1-2 correspond closely to Orchard Lake waterlevels, although no existing outlet had been located under the railroad tracks. The CanadianPacific Railway installed an outlet to Orchard Lake in 1993. The MDNR has determined theLakeville Water Resources Management Plan Page 4-13

OHW to be elevation 978.4. For proposed conditions, the outlet was assumed to be atelevation 978.5. To manage flows for water quality, a gated outlet could be considered.OL-2: The water quality removal efficiency of Pond OL-2-1 could be enhanced by severalmethods: excavating the main body of the wetland to a mean depth of at least 3 feet, flowspreading, or multiple ponds in series.OL-3: The pond located north of the Brackett's Townhomes development (Pond OL-3-2) hasa variable elevation control outlet. The actual flood levels will be dependent on the controlelevation at the time of the storm event. During large storm events, the backwater from OL-3-1 reaches the level of this pond, and the flood levels are the same. A majority of the area inthis subwatershed is located in a golf course. Pond OL-3-2 was formerly the discharge pointfor a sewage treatment plant and testing has shown high phosphorus concentrations in theentire series of ponds, possibly due to loading from sediments. This area should beinvestigated further to see if chemical treatment of bottom sediments would reduce nutrientloading to Orchard Lake.OL-4B: This entire subwatershed is located within the Credit River Township, and drainsunder Judicial Road to OL-4.OL-5: This subwatershed is located within a golf course.OL-6: Approximately 70 acres of this subwatershed is located within the Credit RiverTownship and 21 acres within the city of Lakeville. The existing outlet of Pond OL-6-1 is abox culvert. Based on topographic maps and site observation, the culvert was estimated tobe a 3-foot by 4-foot box, at invert elevation 998.OL-7: Approximately 34 acres of this subwatershed is located within the Credit RiverTownship and 41 acres within the city of Lakeville. For proposed conditions, it was assumedthat a 5-foot dike with a pipe outlet would be constructed across the natural drainage ofPond OL-7-1 to obtain the recommended 100-year flood storage.OL-9: Runoff from approximately 549 acres enters OL-9, and is stored in Pond OL-9-1.Pond OL-9-1 was assumed to be landlocked for existing conditions; after the analysis wascompleted a small agricultural drain tile was discovered that directs flow to Orchard Lake.Past flood levels in Pond OL-9-1 have been low, which indicate that the pond may be agroundwater discharge area. The computed existing 100-year flood level overtops172nd Street West by 0.7 foot. The proposed Pond OL-9-1 would be provided with an outletthat would direct flow to Orchard Lake.OL-10: The existing outlet pipe is several feet above the actual water level noted in the past.The 100-year storage volume is above the outlet elevation, which the water level may neverreach. The existing 100-year flood level of Pond OL-10-1 is approximately 0.8 feet higherLakeville Water Resources Management Plan Page 4-14

than the HWL shown on the Lake Villa Golf Estates plan. The proposed 100-year flood levelis 0.9 feet higher than the HWL shown on the Lake Villa Golf Estates plan. The proposed100-year flood level is still below the elevation of the existing homes adjacent to the pond.The wetland inventory notes that OL-11-1 and several other wetlands in this subwatershedhave excellent potential for modification to improve their nutrient trapping capability.OL-13: For proposed conditions, it was assumed that a 3-foot dike with an inlet structurewould be constructed as the outlet of Pond OL-13-1 to control 100-year flood level.OL-14: For proposed conditions, it was assumed that a 2-foot dike would be constructed atthe proposed outlet of Pond OL-14-1 to increase storage volumes.OL-15: For proposed conditions, it was assumed that a 5-foot dike would be constructed atthe proposed outlet of Pond OL-15-1 to increase storage volumes.OL-16A: The existing 100-year flood level on Pond OL-16-2 overtops the adjacent railroadtracks by 0.2 feet. For proposed conditions, it was assumed that the pond would be enlargedand the outlet under the adjacent railroad tracks would be increased.OL-16B: The proposed conditions assume that the outlet under 172nd Street West would beincreased. The proposed 100-year flood level is 0.5 feet below the existing elevation of172nd Street West.OL-17A1: For fully developed conditions, the increased imperviousness in the area drainingto Pond OL-17-1 will require enlarging the area of the pond. Some of this storage may beobtained from other portions of this subwatershed if desired, as long as the peak dischargefrom OL-17-1 is not increased.OL-17A2: Pond OL-17-3 is a low area at the 15-inch RCP storm sewer inlet in the southeastquadrant of 175th Street West and Junelle Path. The 100-year flood level at this low areaovertops 175th Street West by 0.5 foot under proposed conditions.OL-18C: Pond OL-18-3 was assumed to be enlarged for proposed conditions to maintain areasonable 100-year flood level after development. This additional area could be obtained inthe natural wetland area to the southwest.OL-20: For proposed conditions, it was assumed that a 4-foot dike would be constructed atthe proposed outlet of Pond OL-20-1 to increase storage volumes and reduce downstreamdischarges.OL-24: Based on field investigation and City records, there is no existing outlet for Pond OL-24-1 under the adjacent railroad tracks. The existing 100-year flood level of Pond OL-24-1Lakeville Water Resources Management Plan Page 4-15

overtops the railroad tracks by 0.2 foot. For proposed conditions, a 24-inch RCP outlet wasassumed to be constructed under the adjacent railroad tracks.OL-25 (Kingsley Lake): The MDNR has determined the OHW of Kingsley Lake to beelevation 978.5, which is 0.9 foot above the OHW for Orchard Lake. The existing normalwater level of Kingsley Lake was assumed to be at the OHW. Old construction plans showthat an outlet was constructed from Kingsley Lake (Pond OL-25-1) under Klamath Trail.However, this outlet could not be located, and was assumed to be not operational for existingconditions. It appears that water flows from Kingsley Lake through the groundwater toOrchard Lake. In 1994 an outlet was installed 0.5 feet above the OHW to direct high flows toOrchard Lake. For proposed conditions, the outlet was assumed to be above the OHW atelevation 981.2. To manage flows for water quality, the new outlet is gated.OL-26: Pond OL-26-1 is currently landlocked. An outlet to Orchard Lake was assumed to beconstructed for future conditions. If an outlet is installed, it should be designed to operate insuch a way as to minimize discharge volume to Orchard Lake.OL-27: Pond OL-27-1 is currently landlocked. The NWL of this pond is lower than anyadjacent lakes or ponds, and remains landlocked for proposed conditions. During periods ofhigh water, it may be necessary to temporarily pump water from OL-27-1 to Orchard Lake.As with OL-26-1, minimizing overflow volumes is important in preserving Orchard Lake'swater quality.OL-28A: This subwatershed and Horseshoe Lake (Pond OL-28-1) are located on theboundary with the city of Burnsville. Drainage from Pond OL-28-1 flows north through thecity of Burnsville and into Credit River. Information on Pond OL-28-1 was obtained from theCity of Burnsville Drainage Plan.OL-28B: Pond OL-28-2 is landlocked, and was assumed to remain landlocked for proposedconditions. The 100-year flood level is approximately 12 feet below the overflow elevation.During periods of high water, it may be necessary to temporarily pump water from OL-28-2to OL-28-1, after the peak has past downstream.OL-29: Approximately 48 acres of this subwatershed is located in the city of Lakeville andfour acres within the city of Burnsville.Pond OL-29-1 is landlocked, and was assumed to remain landlocked for proposed conditions.The 100-year flood level is approximately six feet below the overflow elevation. Duringperiods of high water, it may be necessary to temporarily pump water from OL-29-1 north tothe City of Burnsville, after the peak has past downstream. It may be desirable to install anoutlet at the OHW to control the flood level during periods of high water.Lakeville Water Resources Management Plan Page 4-16

4.4 MARION LAKE DISTRICTThe total area of the Marion Lake District, including the lake itself, is 4,987 acres, 4,791 of whichlie within the city of Lakeville. The remaining 196 acres lie in Credit River Township in ScottCounty. The district extends approximately from 210th Street West in the south to Lake VillaGolf Estates in the north, and from Dodd Boulevard in the east to Credit River Township in thewest. The Marion Lake watershed occupies a transitional zone within the city between therolling hills, hardwood forests, and abundant wetlands of the northwestern part of the city andthe level outwash landforms of eastern and southern Lakeville.At present, the area to the southwest of Marion Lake contains rural area with single-familyhousing. The area to the north and east of Marion Lake is more developed with the LakevilleCommerce Center and residential uses. The corridor along Interstate 35 contains some lightindustry and commercial business.The City of Lakeville will begin the development of updated hydrologic and water quality modelsfor the city in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results and anyresulting flow or volume restrictions. The updated modeling will likely result in some changes inpond locations and volumes as well as changes for pipe sizing. As a result, this program will beupdated based on the updated model. This Water Resources Management Plan will then beupdated to include the new design program. In the interim, this section will continue to be thebasis for design of the city’s system needs.The watershed divides of the Marion Lake District are shown on Figure 4.4.1. More detail onthe drainage system is shown on Figure 4.4.2.All of the subwatersheds, with the exception of ML-3 and ML-14, contain ponds and wetlands,which serve as intermediate storage areas. Several of these storage areas remain landlockedexcept during the largest rainfall events. A hydrologic analysis of each wetland was not feasiblefor this plan. Twenty-four of the subwatersheds currently have storage areas with outletstructures. For very long duration events (e.g., 10 or 30-day runoff), the smaller ponds havelimited effectiveness and the runoff is ultimately stored in Marion Lake.Stormwater enters Marion Lake at various points. The largest tributaries enter at the southwestcorner of the lake, via Subwatersheds ML-13 and ML-2. Many smaller inflows are scatteredaround the perimeter of the lake. Subwatersheds ML-25, ML-26, ML-27, ML-28, and ML-29 arecomprised largely of park land; drainage from these areas is presently uncontrolled. Forproposed conditions, it was assumed that this would remain a natural area, with installation ofcontrol structures limited to Pond ML-25-1. Subtrunk storm sewer is proposed for ML-27. Itwas assumed that existing wetlands throughout the watershed would be available for stormwaterstorage and conveyance, in a manner which will disrupt the wetlands as little as possible.Lakeville Water Resources Management Plan Page 4-17

Marion Lake has an area of 589 acres at elevation 982.1. The total volume of the lake at thiselevation is 5,390 acre-feet. Marion Lake is divided into several basins. The middle basin andthe west basin of the lake are located on opposite sides of Interstate 35 and are connected by aculvert. The east bay is the deepest and largest and is separated from the middle basin by twopeninsulas of sand. The sand peninsulas are the remains of a road which crossed the lake.Periodic dredging is required to maintain boating access between the two basins. The areas ofthe individual subbasins are approximately as follows: east bay, 300 acres; middle bay,185 acres; and west bay, 104 acres.The maximum depth of the lake is about 23 feet at the center of the east bay. The middle bay isshallower, while the west bay is shallowest. The mean depths of the east, middle and west basinsare approximately 15, 8, and 5 feet, respectively. These depths are all relative to the outletelevation of 982.1 (1 foot below the OHW). The lake is seldom at this elevation so the depths willgenerally be less than these.As noted, Marion Lake is relatively shallow. Because of this, it is susceptible to intermittentmixing during summer. Most lakes tend to stratify during open water periods due totemperature differences in the water column. This tends to isolate the surface waters(epilimnion) from the deeper waters which are cooler and often become rich in nutrientsreleased from the bottom. Shallow lakes tend to stratify weakly and mix intermittently duringthe course of a summer because they are not deep enough to remain stratified. Exposure towinds, or the "fetch" of a lake, is also a factor in mixing. Marion Lake appears to have thelongest fetch of any lake in the city, and the three basins of the lake lie along a northwest-tosoutheastline that is slightly longer than one mile. The surface water quality of a lake generallybecomes significantly degraded when a mixing event follows a period of stratification.The Dakota County Geologic Atlas (Balaban and Hobbs, 1990) noted that Marion Lake hasfluctuated up to 13 feet. A 1993 well study found that the lake level is controlled more by surfacewater inflows rather than groundwater level fluctuation. Spring time levels may fluctuate withinfiltration from the drift aquifer, but the effect is seasonal. Marion Lake has a gated outlet atthe southeast end of the lake; during occasional periods of high water overflow occurs throughthe structure to a channel and storm sewer system to downtown Lakeville, following the path ofthe natural outlet of the lake.4.4.1 PONDNET Modeling of Marion Lake DistrictThe water quality modeling results presented here were completed in 1993. The City ofLakeville will begin the development of updated hydrologic and water quality models for thecity in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results.This Water Resources Management Plan will be updated to include the new model results.In the interim, this section will continue to be the basis for design of the city’s system needs.The City recently completed the Lakeville Ms4 Loading Assessment and Non DegradationLakeville Water Resources Management Plan Page 4-18

Report, included as Appendix D. This report also provides a general citywide water qualitymodel and analyses.The PONDNET model provides a rough simulation of the hydraulic and phosphorus loadingthat the lake will experience as development proceeds. Especially for Marion Lake, it doesnot provide a full analysis of the lake's dynamics, such as intermittent mixing and loadingfrom bottom sediments. However, the model results may give an idea of future trends. Thelevels predicted by PONDNET for current and future conditions are shown in Table 4.4.1.The PONDNET model predicted a current average annual phosphorus concentration of59 ppb in Marion Lake. This is approximately equal to the observed mean phosphorusconcentration of 36 ppb in the east basin. In reality, the lake should be modeled as threebasins with water quality increasing from west to east. The PONDNET model was developedfor networks of ponds and is not sophisticated enough to accurately model the effect of alarge lake such as Marion Lake.Several mass balance models were used to roughly calibrate the results of the PONDNETmodel to the observed total phosphorus concentration in Marion Lake. The models included:Canfield and Bachman (1981), Dillon and Kirchner (1975), and Larson and Mercier (1976).Annual phosphorus and hydrologic loading, and lake basin characteristics from thePONDNET model were used in the mass balance models. Using the three mass-balancemodels, the calculated phosphorus concentration in the lake ranged from 19 to 71 ppb(compared to the observed concentration of 36 ppb).It should be emphasized that this prediction contains a great deal of uncertainty. Severalmajor factors that determine the water quality of a lake are totally unknown and were notincluded in the model. These include:groundwater inflow volumephosphorus content of the groundwaterbottom loading from sedimentsloading from sediments in Brackett's Crossing Golf CourseThe model uncertainty is also due to the fact that the actual quantity and quality of runofffrom the watershed was estimated and has not been measured. Therefore, the predictedchanges may not actually occur, or may be more severe than predicted. As mentionedpreviously, the limited monitoring data do not show any evidence to date of such a trend, butfurther study is clearly warranted.The predicted increase in hydraulic and phosphorus loadings can be attributed to twochanges: (1) Increased impervious surface due to proposed development; and (2) proposedconstruction of pond outlets from ponds that are currently landlocked.Lakeville Water Resources Management Plan Page 4-19

4.4.2 Flood ProtectionMarion Lake outflow is controlled by an outlet control structure and 30-inch culvert, whichwere installed in 1985. The structure consists of a 4-foot by 6-foot reinforced concrete boxweir, with an overflow elevation of 982.1. The 30-inch culvert has an invert elevation of980.4, and is controlled with a sluice gate. For the existing conditions analysis, outflowentered city storm sewer in downtown Lakeville, and flowed to the east through AirlakeIndustrial Park, via natural drainage. A storm sewer system was constructed in 1994 thatdirects the outflow from Marion Lake southeast along Dodd Boulevard and 210th Street Westto the West Branch of South Creek. This storm sewer system was assumed for the proposedconditions analysis.The outlet structure is necessary because the construction of County Highway 64 blocked thenatural overflow of the lake. This was not a problem until the early 1980s, when the lakelevel began to rise significantly. The lake reached a record elevation of 984.7 in 1984.Flooding of city streets and the threat to area homes prompted the City to seek permissionfrom the MDNR to install the outlet. The outlet was used in September 1992, when MarionLake reached an elevation of 982.6 following heavy rains. It was again used in 1993, andremained in use throughout much of the summer. Marion Lake reached a peak elevation of984.5 in July 1993. During this period, it was discovered that the outlet was operating atapproximately one-half the anticipated capacity. Reasons for this include high tailwaterelevations and high inlet losses.The 100-year flood level on Marion Lake was previously determined to be 984.5 (FIS 1978).A frequency distribution using average water surface elevations for the years 1946 through1990 confirms the FIS elevation. The results were also used as a basis for determiningtailwater control elevations for modeling of upstream pond outlets.It should be noted that the peak elevations of Marion Lake, as computed with HEC-1, differfrom those based on historical lake level data. Unlike most other lakes, Marion Lake is semilandlockedand is often below the outlet level. Making an assumption that the lake is alreadyat the outlet level prior to the extreme rainfall is probably an excessively conservativeassumption. As a reasonable compromise, the HEC-1 model uses the 50 percent probableelevation as a normal (pre-storm) water surface elevation. However, the "normal" watersurface elevation may change slowly with time due to development or long-term climatechange. Such change will cause a corresponding change in predicted flood levels.For each subwatershed and storage pond, peak runoff rates, flood levels, flood dischargesand storage volumes were calculated using the HEC-1 model as described in Appendix A.The results of the modeling are shown in the tables at the end of this section. Information isdescribed as follows:Lakeville Water Resources Management Plan Page 4-20

Table 4.4.2Table 4.4.3Table 4.4.4Table 4.4.5Table 4.4.6Table 4.3.7Existing Conditions—Hydraulic and hydrologicparameters (subwatershed data)Existing Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Existing Conditions—Peak discharges and elevations(flood levels and outflows from ponds)Proposed Conditions—Hydraulic and hydrologicparameters (subwatershed data)Proposed Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Proposed Conditions—Peak discharges and elevations(flood levels and outflows from ponds)4.4.3 Subwatershed DescriptionsFor proposed conditions, it is assumed that future runoff rates from Credit River Townshipinto the western subwatersheds of the Marion Lake District will remain at the existing flowrates. Following is a brief discussion of those subwatersheds for which alterations areproposed, or which have unique features.ML-1: ML-1 includes the area draining directly to Marion Lake. In 1987 the Dakota SWCDstaff noted in the city wetland inventory that Wetland #3085 (MDNR Wetland #19-374W)was a possible future nutrient trap. This wetland is located between the Soo Line tracks andJordan Trail; it should be studied to find ways to improve its nutrient removal functions.ML-2: Pond ML-2-1 (Wetland #960) is considered to be part of Marion Lake, with similarflood levels. For low flow events this pond serves to reduce nutrient inflows to Marion Lake.It should be studied to find ways to improve its nutrient removal functions.ML-3: Two ponds were constructed in this subwatershed in 1993. ML-3-1 is a wet pond,while ML-3-2 is a dry pond. The addition of these ponds will benefit the quality of the runoffbefore it enters Marion Lake.ML-5: This subwatershed has limited storage in the eastern portion. If possible, runoff fromthis area should be treated by detention storage before discharge to Subwatershed ML-2.ML-7: Pond ML-7-1 (Wetland #2949) presently has a 72 inch outlet directing flow easterlyunder the I35 freeway.Lakeville Water Resources Management Plan Page 4-21

ML-8: Pond ML-8-1 is a wetland area, and is controlled by a 30-inch outlet. If unaltered,this pond will overtop Keokuk Avenue during the 10-year flood event under futuredevelopment conditions. A larger culvert with a lower invert was assumed for proposedconditions to prevent overtopping of Keokuk Avenue.ML-9: There are several small wetland areas in this subwatershed. Runoff eventually drainsacross County Road 70 to Subwatershed ML-8, via a 4-foot by 6-foot box culvert. This planrecommends that the existing natural pond area be enlarged to provide additional storage forfuture conditions. A restrictive outlet was assumed to control discharge to the existing 4 by6-foot box culvert. The box culvert will continue to receive local ditch drainage.ML-10: For proposed conditions, additional storage was assumed in this subwatershed tocontrol discharge to Subwatershed ML-7.ML-11: This area is the site of a concrete mix plant, and gravel mining activity has alteredthe landscape considerably. The J.L. Shiely Company Post-Mining Grading Plan"Concept A", November 1990, was used to determine elevations for the proposed ponds.Under future conditions, this subwatershed will contain less area to the west and more areato the north than it does under existing conditions. This reflects anticipated changes in thefloodplain after the Shiely property is developed. With the development, this planrecommends that Pond ML-11-1 be constructed to control flow to Subwatershed ML-17. Inplanning for end use of this area, consideration should be given to enlargement of theproposed ponding to reduce future nutrient flows to Marion LakeML-12: Approximately 110 acres of this subwatershed lie within the city of Lakeville; theremaining 74 acres lie within Credit River Township. This subwatershed contains a largeamount of wetland area, some of which is being purchased by the U.S. Fish and WildlifeService. The subwatershed drains to Pond ML-12-1, located in Credit River Township. Flowis then discharged through a culvert across County Road 70 and through a drainage channel,before being stored in Pond ML-22-1.ML-13: Pond ML-13-1 is considered to be part of Marion Lake, with similar flood levels.ML-14: This subwatershed is presently landlocked, and drains to a large low area. The lowarea was man-made from gravel mining and is not classified as wetland. For proposedconditions, a ponding area was assumed to be developed in the southeast corner of the lowarea, with a culvert constructed to convey outflow to Subwatershed ML-13. Alternatives tothis outlet should be considered, if possible, to avoid increasing nutrient loading to MarionLake.ML-17: Pond ML-17-1 is presently divided into two basins: a large upper pond and a smallerlower pond. The upper pond receives the majority of the runoff from the subwatershed, anddischarges to the lower pond via a culvert of unknown dimensions. The lower pond is 10 feetLakeville Water Resources Management Plan Page 4-22

lower in elevation that the upper pond. The lower pond discharges to Subwatershed ML-15,but will backflow to the upper pond if the elevation exceeds 1003. It is anticipated that asimilar scenario will exist during future conditions. When the Shiely mining area isdeveloped, runoff from the southern portion of ML-17 will be diverted to Subwatershed ML-11.ML-18: The area of this subwatershed will increase under proposed conditions, as describedfor Subwatershed ML-11. Pond ML-18-1 was assumed to be constructed in the existing swaleto control runoff to Subwatershed ML-17. The Shiely Post-Mining Grading Plan "Concept A",November 1990, was used to determine proposed pond elevations.ML-19: Construction of Pond ML-19-1 was assumed for future conditions to controldischarge to Subwatershed ML-17. This area is included in the Shiely Post-Mining GradingPlan, but the plan does not include a pond at this location. Because of the large drainagearea, increasing detention storage in this area would help to reduce nutrient loading toMarion Lake. This should be reviewed as part of end use planning for the Shiely operation.ML-20: For future conditions, it was assumed that a 5-foot dike would be constructed at theproposed outlet of Pond ML-20-1 (Wetlands #745, 747, 751, 752, 753 and 761) to increase thestorage volume. This storage is necessary to protect Lake Marion's water quality andincrease the storage volume. This storage is necessary to restrict discharge, improve waterquality and prevent flooding in downstream subwatersheds. The wetlands are classified asType III cattail wetlands that have been excavated in some places.ML-21: Approximately 70 acres of this subwatershed lie within the city of Lakeville, whilethe remaining 22 acres lie within Credit River Township.ML-22: Approximately 149 acres of this subwatershed lie within the city of Lakeville, whilethe remaining 36 acres lie within Credit River Township.ML-23A: Approximately 67 acres of this subwatershed lie within the city of Lakeville, whilethe remaining 52 acres lie in Credit River Township. This area includes large wetland areas,and the outflow drains to ML-20. For future conditions, it was assumed that a 6-foot dikewould be constructed at the proposed outlet of Pond ML-23-1 (Wetlands #2515 and 2472) toincrease storage volume. This will reduce flood flows and increase nutrient retention.ML-23B: For future conditions, it was assumed that a three-foot dike would be constructedat the proposed outlet of Pond ML-23-2 (Wetlands #736 and 737) to increase the storagevolume and increase nutrient trapping capacity of these wetlands.ML-24A: Outflow from Pond ML-24-1 presently overtops the adjacent road before flowingthrough a natural swale to Marion Lake. Under proposed conditions, it was assumed that a36-inch outlet would be installed, with an overflow elevation of 987.0. This would requireLakeville Water Resources Management Plan Page 4-23

aising the roadway. If the road remains at present grade (overflow elevation 985.5), it willbe overtopped slightly during the 100-year flood event.ML-25: This subwatershed is located almost entirely within Ritter Farm Park. Underproposed conditions, an outlet was assumed to be constructed for Pond ML-25-1, to preventovertopping of the existing road. Wetland #960 is adjacent to Pond ML-25-1; the citywetland inventory notes that it has good potential for increasing floodwater storage. Thiswould also increase its nutrient trapping capacity.ML-26: The majority of this subwatershed lies within Ritter Farm Park boundaries.Consequently, installation of storm sewer is not proposed.ML-27: Runoff from this wooded subwatershed drains into a large wetland, which overflowsto Subwatershed ML-26. An outlet structure is not proposed for the wetland, as it is withinRitter Farm Park boundaries. For future conditions, it was assumed that the wetland wouldreceive runoff from the existing tributary area.ML-28: This subwatershed contains significant wetland area, and lies partially within RitterFarm Park boundaries. Because of the large wetland area outside of the Park, only lowdensity housing is probable and no subtrunk storm sewer was assumed for proposedconditions. Flow will be conveyed to Marion Lake via existing natural drainage channels.The city wetland inventory suggested that Wetland #706 is a good nutrient and sedimenttrap and there is potential for increasing floodwater storage at this point. This should beinvestigated further.ML-29: Approximately 79 acres of this subwatershed are within the city of Lakeville, whilethe remaining 13 acres lie within Credit River Township. Drainage is presently controllednaturally with several large upland ponds draining into a swale, which conveys flow toSubwatershed ML-28. It was assumed that this natural drainage system remain unalteredfor future conditions.ML-31: A portion of this subwatershed is located within a golf course. The outlet fromPond ML-31-1 was assumed to be increased for proposed conditions. Wetlands #785 and 787in this subwatershed were listed in the city wetland inventory as being a good potentialponding area. Since they will not be needed for rate control, their nutrient trapping functionshould be emphasized, if possible, to help protect Lake Marion.ML-32: Subwatershed ML-32 is partly within a golf course. An outlet was assumed to beconstructed from Pond ML-32-1 (Wetlands #2752, 2764 and 2784) for proposed conditionsto convey flow to Subwatershed ML-31. The water quality implications of this outlet shouldbe studied carefully before construction to avoid increasing loading to the north arm ofMarion Lake. If an outlet is unavoidable, the nutrient trapping capacity of the pond shouldbe maximized by placing the outlet as high as possible and providing sedimentation capacity.Lakeville Water Resources Management Plan Page 4-24

ML-34: This subwatershed contains a large amount of wetland area. For proposedconditions, Pond ML-34-1 will require a larger outlet to convey runoff to Marion Lakewithout overtopping 185th Street West. Vertical distance for pipe placement is limited by thetailwater elevation of Marion Lake and the elevation of the existing roadway. Runoff fromupstream watersheds passes through Wetlands #849 and #850 (MDNR #19-349W) beforereaching Pond ML-34-1 (Wetland #835). These are type III cattail and bulrush wetlands.The Dakota SWCD noted in the city's wetland inventory that they are good nutrient andsediment traps. If the two larger wetlands could be modified to increase their nutrienttrapping capability the nutrient load to Lake Marion could be reduced.ML-39: Presently, outflow from Pond ML-39-1 is regulated by a natural overflow to MarionLake. A constructed outlet was assumed under future conditions to control outflow toMarion Lake.ML-42: This subwatershed drains to ML-41 via twin 15-inch culverts under the railroadtracks. The culverts are in poor condition, but theoretically have the capacity for the 100-year flood.ML-46: Construction of a 5-foot dike and outlet structure is proposed for an existingwetland (Pond ML-46-1) to create additional storage volume for future conditions.Controlling outflow to ML-45 will reduce the potential for overtopping of Kenwood Trail,adjacent to Pond ML-45-1, in future conditions.ML-47: This area presently contains little storm sewer, with the exception of twin 24-inchculverts under 185th Street West. It was assumed that these culverts would be replaced witha larger culvert to reduce the probability of flooding under proposed conditions. A drop orweir structure will likely be necessary at the inlet, as the roadway elevation limits verticalclearance.ML-48: The area of this subwatershed will be increased under future conditions withadditional areas from Subwatershed ML-50. This change reflects proposed installation ofstorm sewer along Kenwood Trail. Pond ML-48-1 will overtop 199th Street West and Upper196th Way by 0.1 feet during the 10-year flood event, under proposed conditions. Preventingthe overtopping would require raising the roadway to create more flood storage volume, andinstalling a larger culvert.ML-49: No changes are proposed for this area, although the subwatershed gains area fromSubwatershed ML-50 under proposed conditions.ML-50: This subwatershed will be smaller under proposed conditions, as runoff from someareas will be diverted to Subwatersheds ML-48 and ML-49. It is proposed that all runofffrom ML-50 be directed into existing Pond ML-50-1. The storage volume of this pond will beLakeville Water Resources Management Plan Page 4-25

increased to contain future runoff and decrease the peak discharge to ML-48.ML-51: This area is subdivided into ML-51A and ML-51B under proposed conditions. Thisreflects the anticipated addition of storm sewer along Kenwood Trail. Pond ML-51-1presently has no constructed outlet. The overflow is a wooded dike which separates the pondfrom Marion Lake. The present overflow situation will meet future requirements, although itmay be desirable to provide a culvert structure or weir-type overflow structure to preventerosion of the dike. Installation of a culvert was assumed for modeling the proposedconditions.4.5 NORTH CREEK DISTRICTThe total area of the North Creek watershed at the Lakeville-Farmington border is approximately12,200 acres, 5,737 of which lie within the city of Lakeville. Of the remaining area, 297 acres liewithin the city of Farmington and 6,150 acres lie within the city of Apple Valley. The district islocated in the portion of the city of Lakeville lying generally north of 180th Street.The North Creek District is comprised largely of level outwash landforms, with fewer wetlandsand forest than the western portion of the city. The district is drained by North Creek, atributary of the Vermillion River. The creek has two branches. The West Branch of North Creekis a perennial stream fed by groundwater discharge during dry weather. The Main Branch ismore intermittent in flow.The West Branch of North Creek begins in the western portion of the district, between Highviewand Ipava Avenue, and flows east. The West Branch roughly divides the district west to eastbefore entering the city of Farmington east of Pilot Knob Road.The Main Branch extends north into Apple Valley. The watershed of the Main Branch includes asignificant portion of the city of Apple Valley, extending as far as Alimagnet Lake. The MainBranch joins the West Branch in Section 12, about one-half mile downstream from Pilot KnobRoad. The city of Apple Valley has constructed a 60-inch storm sewer to convey Main Branchflow from a 10-acre stormwater pond north of County Road 46 to Pond NC-9-1, located east ofPilot Knob Road. The sewer would follow the existing channel alignment.The western part of the North Creek District is developed primarily in residential uses. Theeastern portion is generally agricultural, with the exception of a gravel mining operation in theextreme northeast corner of the city. A yard waste composting site is operated east of Pilot KnobRoad in NC-1 and NC-3.The City of Lakeville will begin the development of updated hydrologic and water quality modelsfor the city in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results and anyLakeville Water Resources Management Plan Page 4-26

esulting flow or volume restrictions. The updated modeling will likely result in some changes inpond locations and volumes as well as changes for pipe sizing. As a result, this program will beupdated based on the updated model. This Water Resources Management Plan will then beupdated to include the new design program. In the interim, this section will continue to be thebasis for design of the city’s system needs.The subwatershed divides of the North Creek District are shown on Figure 4.5.1. The drainagesystem is shown in greater detail on Figure 4.5.2.North Creek does not provide the direct or indirect body contact recreation that many lakeswould provide. The creek and its associated ponds and wetlands do not sustain significant fishpopulations, either in Lakeville or downstream in Farmington. In Farmington, North Creekenters the Vermillion River at a point where it is no longer a designated trout stream so themanagement of the District will not have an impact on the trout fishery.The beneficial uses of North Creek are not as obvious as the uses of lakes but the Creek is still asignificant resource to the neighborhoods through which it flows. Probably the most significantuse of the creek will be as an aesthetic and wildlife resource. The Lakeville Park Plan envisions asystem of parks and trails along North Creek forming a linear park within a conservation area.Existing parks adjacent to North Creek include Dakota Heights Park, North Park, WoodburyPark, Foxborough Park, Bunker Hill Park, Valley Lake Park, Parkview Park, Sleepy Hollow Park,Dodd Trail Park, Meadowbrook Linear Trail, and acquired parkland in the southwest corner ofSection 1. Additional park acquisition is planned as development progresses to the east. Theentire North Creek park system will be intimately connected to the creek and will require thatthe clarity of the creek and the wetlands associated with the creek be maintained.During development of properties in Subwatershed NC-51D, it was found that a portion of thewetland contained a threatened species (valerian) which is sometimes found in fens. Golf coursedevelopment avoided this area and stormwater will not be routed into it. Because the watershedof the wetland will be limited, the groundwater system will affect it more than the stormwaterpractices in the tributary area.Based on these park and wildlife values, it is proposed that North Creek be managed as CategoryIII waters to maintain the aesthetic and wildlife values required for a park system. Thismanagement goal should also include meeting regional goals for non-degradation andimplementation of best management practices for urban watersheds. Because the stream andwetlands are not lakes, transparency goals for North Creek are probably not appropriate; a goalof maintaining a total suspended solids concentration of less than 30 mg/L and a minimum dailydissolved oxygen level of 5 mg/L would appear to be more reasonable. These goals may have tobe revised if better monitoring data are obtained. These goals will be served by the same bestmanagement practices that are employed in other districts for phosphorus reduction to maintaintransparency.Lakeville Water Resources Management Plan Page 4-27

4.5.1 PONDNET Modeling of North Creek DistrictThe water quality modeling results presented here were completed in 1993. The City ofLakeville will begin the development of updated hydrologic and water quality models forthe city in 2008. These updated models will account for changes that have occurred inthe system over the last 13 years and will conform to the VRWJPO hydrologic modelresults. This Water Resources Management Plan will be updated to include the newmodel results. In the interim, this section will continue to be the basis for design of theCity’s system needs. The City recently completed the Lakeville Ms4 Loading Assessmentand Non Degradation Report, included as Appendix D. This report also provides ageneral citywide water quality model and analyses.Because data on water quality for North Creek are lacking, PONDNET modeling of the NorthCreek District was relied upon for comparison of water quality under existing and proposedconditions. The PONDNET model predicts a 35 percent increase in the average surfacevolume for North Creek under proposed conditions. The estimated phosphorus loaddecreases by approximately 15 percent under developed conditions and the averagephosphorus concentration decreases by 37 percent according to the PONDNET modelresults. Table 4.5.1 summarizes the PONDNET results, for the location at which NorthCreek leaves the city of Lakeville.Information on phosphorus loading from inflows to Lakeville from the City of Apple Valleycan be found in Chapter 5 of the Apple Valley Stormwater Management Plan (2007).4.5.2 Flood ProtectionThe flood level of North Creek is primarily controlled by the size of culverts at major roadcrossings. These include, primarily, Highview Avenue, Cedar Avenue, Dodd Boulevard,Flagstaff Avenue and Pilot Knob Road.For each subwatershed and storage pond, peak runoff rates, flood levels, flood dischargesand storage volumes were calculated using the HEC-1 model as described in Appendix A.The results of the modeling are shown in the tables at the end of this section. Information isdescribed as follows:Table 4.5.2Table 4.5.3Table 4.5.4Existing Conditions—Hydraulic and hydrologicparameters (subwatershed data)Existing Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Existing Conditions—Peak discharges and elevations(flood levels and outflows from ponds)Lakeville Water Resources Management Plan Page 4-28

Table 4.5.5Table 4.5.6Table 4.5.7Proposed Conditions—Hydraulic and hydrologicparameters (subwatershed data)Proposed Conditions—Critical events and correspondingrunoff (peak runoff rates and volumes from watersheds)Proposed Conditions—Peak discharges and elevations(flood levels and outflows from ponds)The discharge computed using the HEC-1 model was compared to discharge data obtainedfrom the 1978 Flood Insurance Study (FIS) and the 1991 Revision of Hydrology for the SouthFork of North Creek. North Creek discharges were compared at Cedar Avenue, FlagstaffAvenue, and Pilot Knob Road, as well as at the Lakeville city limits. The HEC-1 dischargescompared reasonably well with the earlier published discharges, except at the corporatelimits. Here, the FIS predicts a discharge nearly twice that of the present study. Thedifference can be attributed to significant storage in the mining land areas in Lakeville andApple Valley contributing to Pond NC-9-1. This storage area was not included in the FIS, butwas included in the present study, reducing the discharges considerably. Other differencescan be attributed to modifications to the drainage system and increasing development of therural areas surrounding North Creek.4.5.3 Subwatershed DescriptionsFor proposed conditions, it is assumed that runoff from Apple Valley, which flows intoSubwatersheds NC-31 and NC-16, will conform to the rates shown in the Apple Valley SurfaceWater Management Plan. Following is a brief description of subwatersheds for whichalterations are proposed, or which have unique features.NC-1: North Creek flows through this subwatershed and into the city of Farmington. It isassumed that North Creek will be unaltered in this subwatershed under proposed conditions.NC-9: This subwatershed contains a large pond, NC-9-1, which is adjacent to an existingModel Stone Company gravel mining operation. For proposed conditions, this subwatershedwas divided into Subwatersheds NC-9A, NC-9B and NC-9C. NC-9A and NC-9B are includedin the post-mining Nordic Square Development Plan (April, 1991). Discharge from theproposed development will overflow into Pond NC-9-1. Outflow from the pond is presentlycontrolled by twin 48-inch culverts and is tributary to North Creek.NC-11: This subwatershed was divided into NC-11A, NC-11B and NC-11C for proposedconditions. These subwatersheds are part of the proposed Nordic Square Development.Based on existing end-use plans, Watershed NC-11A will contain a large pond, NC-11-1,which will receive discharge from smaller Ponds NC-11-2, NC-11-3 and NC-13-1. Pond NC-11-1 will receive little direct overland flow.Lakeville Water Resources Management Plan Page 4-29

NC-13: Cobblestone Lake in Apple Valley (EVR-44) has a pumped outlet that is designed tooperate in an extreme event. This discharge would be routed via force main to Lakevillethrough this subwatershed district to Lakeville Pond NC-9-1. Probably due to highinfiltration rates in Cobblestone Lake, the pump has never been operated except for testingand maintenance since it was installed in 2001. The boundaries of this subwatershed wererevised for proposed conditions to reflect alterations resulting from the proposed NordicSquare Development. Pond NC-13-1 was assumed to be constructed as shown in the plans,and will discharge to Pond NC-11-1.NC-14: This subwatershed was divided into NC-14A and NC-14B for proposed conditions, toreflect alterations of the watershed from the proposed Nordic Square Development.Pond NC-14-1 will receive inflow from Ponds NC-14-2, NC-9-2 and NC-9-3, and will receivelittle direct overland runoff. Outflow from this pond will be directed to Pond NC-9-1.NC-16: Water enters this Lakeville subwatershed from Apple Valley Pond WVR-443 andflows from here to Lakeville Pond NC-9-1. By mutual agreement between Apple Valley andLakeville, this subwatershed will receive a 100-year peak flow of 80 cfs from Apple Valleyunder fully developed conditions. For modeling it was assumed that 80 cfs would flow for allof the runoff events. The City of Apple Valley has constructed a NURP/stormwater pondnorth of County Road46. A 60-inch storm sewer conveys the flow NC-9-1.NC-20: A channel and weir was recently constructed in this subwatershed to increase lowflowconveyance capacity of North Creek. Both existing and proposed conditions reflect thisconstruction.NC-31: This watershed contains Valley Lake, the only lake in the district. When CountyRoad 46 was re-constructed runoff from Apple Valley was rerouted away from Valley Lake toApple Valley Pond WVR-443. From there the water travels back into Lakeville viasubwatershed NC-16 and ultimately to Lakeville Pond NC-9-1.NC-38: Runoff from this subwatershed drains north, across 160th Street into Apple Valley,where it travels through Apple Valley pond WVR-P50 and eventually to WVR-443. Fromthere the water travels back into Lakeville via subwatershed NC-16 and ultimately toLakeville Pond NC-9-1.NC-45: It was assumed that water quality Pond NC-45-1 would be constructed on the westside of Highview Avenue under proposed conditions. The wet detention storage volume ofthis pond will be approximately 4 acre-feet. It was assumed that the pond would beconstructed for water quality purposes and would have insignificant flood storage capacity.NC-50: This subwatershed was subdivided into four smaller subwatersheds to reflect thedrainage plan of the Crystal Lake Golf Course. Subwatershed ML-50D may contain a fen,which is being protected.Lakeville Water Resources Management Plan Page 4-30

NC-51: This subwatershed was divided into ten smaller subwatersheds to reflect thedrainage plan of the Crystal Lake Golf Course.NC-62: Pond NC-62-1 presently overflows through a natural swale. It was assumed that anoutlet structure will be constructed from Pond NC-62-1 under proposed conditions.4.6 SOUTH CREEK DISTRICTThe South Creek District extends from the southern boundary of the city northward to between215th Street West and 185th Street West. The district lies within the Vermillion RiverWatershed, which is managed by the Vermillion River WMO. Drainage from the South CreekDistrict flows into the Vermillion River, which discharges to the Mississippi River.Runoff from the majority of this district flows in channels to the Vermillion River. Runoff from76 acres in the southwest corner of the city flows to the southwest, into the Credit RiverTownship. This area also eventually discharges to the Vermillion River.There are three main channels within this district that outlet to the east into the city ofFarmington. The main channel is South Creek, which exits the city through Subwatershed SC-11.The other two channels exit the city just north and south of the main channel, the South Branchof South Creek through Subwatershed SC-1 and the East Branch of South Creek throughSubwatershed SC-69.Runoff from approximately 4,865 acres is tributary to the South Creek channel. This includesapproximately 23 acres from New Market Township that contributes runoff to the West Branchof South Creek. There are two tributaries referred to by the MDNR as the north branch andsouth branch. Runoff from approximately 2,467 acres is tributary to the South Branch of SouthCreek, including roughly 1,527 from New Market and Eureka Townships. Runoff from 602 acresis tributary to the northern channel.South Creek begins north of 192nd Street between Dodd Boulevard and Kenwood Trail. SouthCreek then flows to the southeast, past the new Lakeville High School and City Hall, and flowsjust east of the downtown area between Aranson Park and Upper 206th Street West. A longsection adjacent to 206th Street was improved in 1988 by the city to reduce flooding. The WestBranch, begins west of I-35 near the city boundary with New Market Township. The WestBranch flows through Airlake Industrial Park, past Schmitty's and Grist Mill, and joins SouthCreek just south of Highway 50 between Hamburg Avenue and Cedar Avenue. The MarionBranch of South Creek directs the outflow from Lake Marion to the southeast and enters theWest Branch south of Highway 50, west of Holyoke Avenue.The outlet from Marion Lake is 1 foot below the Ordinary High Water Level (OHW) of 983.1.Lakeville Water Resources Management Plan Page 4-31

Historical lake levels have fluctuated with climatic conditions. Using empirical data, there is aseven percent annual probability that Marion Lake will be at or above the overflow elevation (orapproximately once every 14 years). Section 4.4 contains more detailed information on MarionLake.The South Creek District is still largely undeveloped. The existing development is mainly withinthe downtown area and the Airlake Industrial Park. Other land use is mainly agriculture or openfields.The City of Lakeville will begin the development of updated hydrologic and water quality modelsfor the city in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results and anyresulting flow or volume restrictions. The updated modeling will likely result in some changes inpond locations and volumes as well as changes for pipe sizing. As a result, this program will beupdated based on the updated model. This Water Resources Management Plan will then beupdated to include the new design program. In the interim, this section will continue to be thebasis for design of the city’s system needs.The watershed divides of the South Creek District are shown on Figure 4.6.1. The drainagesystem is shown in greater detail on Figure 4.6.2.4.6.1. PONDNET Modeling of South CreekThe water quality modeling results presented here were completed in 1993. The City ofLakeville will begin the development of updated hydrologic and water quality models for thecity in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results.This Water Resources Management Plan will be updated to include the new model results.In the interim, this section will continue to be the basis for design of the city’s system needs.The City recently completed the Lakeville Ms4 Loading Assessment and Non DegradationReport, included as Appendix D. This report also provides a general citywide water qualitymodel and analyses.The land use tributary to South Creek is currently composed of large areas of agriculturalland interspersed with developed areas. South of 210th Street West is a large industrial area.Business and residential developments are located in the downtown area. Futuredevelopment within the district will be a combination of industrial areas south of 210thStreet West and mainly residential areas north of 210th Street West.The PONDNET model for the southern channel (tributary to Subwatershed SC-1) includesdata from the runoff from New Market and Eureka Townships. For areas outside the city ofLakeville, the future development levels were assumed to remain at the existing levels.For the three channels, the estimated future total phosphorus load and average phosphorusLakeville Water Resources Management Plan Page 4-32

concentration are at or below the estimated existing levels.The results of the existing and future conditions PONDNET models for the South CreekDistrict are tabulated in Table 4.6.1. The estimated average surface inflow volume forfuture conditions is significantly higher than under existing conditions. Under developedconditions, the amount of runoff increases with the increased imperviousness of residentialand commercial development. Therefore, the total volume of runoff will be higher than inexisting conditions even though rates will be controlled to pre-developed conditions.All wetlands shown on the National Wetland Inventory map are assumed to be preserved forproposed conditions and all stormwater ponds will be constructed with an average of at least3 feet of water quality storage (i.e., dead storage) below the runout elevation.A large number of ponding areas are proposed under future development conditions. Toachieve the desired removal efficiency of 60 percent, the average depth of several of thelarger ponds was increased (up to as much as 6 feet).4.6.2 Flood ProtectionFor each subwatershed and storage pond, peak runoff rates, flood levels, flood dischargesand storage volumes were calculated using the HEC-1 model as described in Appendix A.The results of the modeling are shown in the tables at the end of this section. Information isdescribed as follows:Table 4.6.2Table 4.6.3Table 4.6.4Table 4.6.5Table 4.6.6Table 4.6.7Existing Conditions—Hydraulic and hydrologicparameters (subwatershed data)Existing Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Existing Conditions—Peak discharges and elevations(flood levels and outflows from ponds)Proposed Conditions—Hydraulic and hydrologicparameters (subwatershed data)Proposed Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Proposed Conditions—Peak discharges and elevations(flood levels and outflows from ponds)4.6.3 Subwatershed DescriptionsThe subwatersheds described in the following sections have unique characteristics orsignificant alterations from existing to proposed conditions.Lakeville Water Resources Management Plan Page 4-33

SC-1: Subwatershed SC-1B covers approximately 153 acres, and is located entirely in EurekaTownship. Runoff from SC-1B flows north into the city of Lakeville Subwatershed SC-1A.SC-2: Subwatershed SC-2B covers approximately 160 acres, and is located entirely in EurekaTownship. The southern channel flows through Subwatershed SC-2B into the southeasternportion of Subwatershed SC-2A (in the city of Lakeville). Pond SC-2-1 was constructed inconjunction with the Ryt Way development, located north of the pond.SC-3: Subwatershed SC-3B covers approximately 157 acres, and is located entirely in EurekaTownship. The southern channel flows through Airlake Industrial Airport in Eureka. Runofffrom Subwatershed SC-3A flows south into Subwatershed SC-3B.SC-4: Subwatershed SC-4B covers approximately 58 acres, and is located entirely in EurekaTownship. Runoff from Subwatershed SC-4A flows south into the southern channel inEureka.The southern channel directs flow under Highview Avenue and the adjacent railroad tracksthrough existing box culverts located in Eureka Township. The 100-year flood level behindthese box culverts (Pond SC-4-1) floods an existing low area that extends north into the cityof Lakeville. The existing and proposed 100-year floods overtop Highview Avenue (currentlya gravel road) by approximately 2.8 feet.Construction of a 10-acre pond (SC-4-2) was assumed in Subwatershed SC-4A for proposedconditions, to decrease the peak flow into Eureka Township. It was assumed that a 4-footdike would be constructed at the outlet of Pond SC-4-2 to increase the storage volume forfuture conditions. Outflow from this pond is directed east of Highview Avenue into thesouthern channel.SC-5: Subwatershed SC-5 includes approximately 159 acres that is located entirely in EurekaTownship. The southern channel flows through this subwatershed in Eureka Township.SC-6: To decrease the 100-year peak discharge to Eureka Township for proposed conditions,it was assumed that the existing pond would be enlarged to 7 acres. It was assumed that a 2-foot dike would be constructed at the outlet of Pond SC-6-1 to increase the storage volumefor future conditions.SC-7: For proposed conditions, it was assumed that a 4-acre pond would be constructed inthe existing low area west of Dodd Boulevard, with a reduced outlet under Dodd Boulevard.SC-8: Subwatershed SC-8B covers approximately 114 acres, and is located entirely in EurekaTownship. The southern channel flows through Subwatershed SC-8B in Eureka Township.Runoff from Subwatershed SC-8A flows into Pond SC-8-1, which has a natural overflow toLakeville Water Resources Management Plan Page 4-34

Subwatershed SC-6.For proposed conditions, it was assumed that an outlet would be installed on existingPond SC-8-1, directing flow to Pond SC-6-1.SC-9: Runoff from Subwatershed SC-9A flows into the southern channel, and intoSubwatershed SC-9B located in Eureka Township. The southern channel directs flow underDodd Boulevard through an existing box culvert in Eureka Township. The existing 100-yearflood level behind this box culvert (Pond SC-9-1) floods an existing wetland area that extendsnorth into the city of Lakeville.Existing ponding areas in the Eureka Township section of this subwatershed were estimatedfrom U.S.G.S. quadrangle maps, and approximate storage was used in the hydrologicanalysis.SC-10: Subwatershed SC-10B includes runoff from approximately 531 acres in New Marketand Eureka Townships. Existing ponding areas in the Eureka Township section of thissubwatershed were estimated from U.S.G.S. quadrangle maps, and approximate storage wasused in the hydrologic analysis.SC-11: The section of South Creek located in this subwatershed has been designated by theMDNR as a trout stream. Management goals for the trout stream are discussed inSection I.D.2. A roadway that would cross South Creek at this location is planned. Culvertsinstalled under the road would be sized to store large storm events and control the rate ofrelease.SC-12: The section of South Creek located in this subwatershed has been designated by theMDNR as a trout stream. Management goals for the trout stream are discussed inSection I.D.2. The existing storage volume of Pond SC-12-1 was assumed to be the channelstorage from Cedar Avenue to Hamburg Avenue.SC-13: For proposed conditions, the channel storage of Pond SC-13-1 was computedassuming a trapezoidal channel at the existing channel slope. Alternate channel designs maybe necessary to attain the storage within existing wetland areas.SC-15: The existing storage volume of Pond SC-15-1 was assumed to be the channel storagecontained from Hamburg Avenue to the boundary with Subwatershed SC-16. The existingbridge under Hamburg Avenue has an 18-inch diameter sanitary sewer pipe suspendedwithin the bridge opening.In 1994, the channel was enlarged at the Grist Mill development to provide additionalstorage volume in Pond SC-15-1. The existing bridge at Hamburg was replaced with 2 12'x7'box culverts. The proposed conditions analysis reflects these changes.Lakeville Water Resources Management Plan Page 4-35

SC-17: The existing storage volume of Pond SC-17-1 was assumed to be the storage in thechannel between the railroad tracks and Dodd Road. The existing and proposed 100-yearflood level of Pond SC-17-1 overtops the adjacent railroad tracks by 0.1 foot.For proposed conditions, the area of Pond SC-17-1, at normal water level, was increased to5 acres. It was assumed that much of the floodplain storage would be filled for proposedconditions. It may be desirable to increase the storage capacity of Pond SC-17-1 further anddecrease the flood level at the railroad tracks and Holyoke Avenue. The mean depth ofPond SC-17-1 was assumed to be 4 feet, to obtain the desired water quality removal efficiencyfor South Creek.SC-23: The existing storage volume of Pond SC-23-1 was assumed to be the channel storagecontained within the subwatershed boundaries. The proposed channel storage wascomputed for a trapezoidal channel at the existing channel slope. Alternate channel designsmay be necessary to attain the storage within existing wetland areas.SC-24: The existing storage volume of Pond SC-24-1 was assumed to be the channel storagecontained within the subwatershed boundaries. The existing 100-year flood level ofPond SC-24-1 overtops 215th Street West by 0.6 foot.To decrease the peak flow for proposed conditions, construction of a 6-acre pond wasassumed in this subwatershed. The 100-year flood level of Pond SC-24-1 was reduced so that215th Street West is not overtopped for proposed conditions. The proposed channel storagewas included in the Pond SC-24-1 volume, and was computed assuming a trapezoidalchannel at the existing channel slope. Alternate channel designs may be necessary to attainthe storage within existing wetland areas.SC-25: The existing storage volume of Pond SC-25-1 was assumed to be the channel storagecontained within the subwatershed boundaries. The existing 100-year flood level ofPond SC-25-1 overtops Kaparia Avenue by 0.5 foot. Kaparia Avenue is currently a gravelroad, and was assumed to be raised at least 1 foot for future conditions.To decrease the peak flow for proposed conditions, a 10-acre pond was assumed in thissubwatershed. The outlet of Pond SC-25-1 was increased for proposed conditions.The channel in this subwatershed flows through an existing box culvert under KenrickAvenue. The existing 100-year flood level at Kenrick Avenue is approximately at theoverflow. The 100-year flow rate will be reduced for future conditions with additionalupstream ponding.SC-26: To reduce the peak flow rates downstream for proposed conditions, Pond SC-26-1was assumed to be enlarged to 3 acres.Lakeville Water Resources Management Plan Page 4-36

SC-27: The existing overflow for Pond SC-27-1 is to the north in the drainage swale west of I-35. Overflow in this swale drains to Pond SC-26-1.Construction of a 3-acre pond was assumed in this subwatershed for proposed conditions toreduce the peak flow rates downstream.SC-28: The existing outlet from Pond SC-28-1 is the overflow at Laigle Avenue. Underexisting conditions, the 100-year flood overtops Laigle Avenue by 0.2 foot. For proposedconditions, a 1-acre pond with an outlet to SC-27 was assumed to reduce the flood level.Laigle Avenue is currently a gravel road, and was assumed to be raised at least 0.5 foot forfuture conditions.SC-29: Pond SC-29-1 currently overflows east through a natural drainage swale to SC-33. Itwas assumed that a 3-foot dike would be constructed at the proposed outlet of Pond SC-29-1to increase the storage volume for future conditions.SC-30: Runoff from this subwatershed currently flows east through a natural drainage swaleto SC-27. Construction of a 3-acre pond was assumed for future conditions, to reduce the100-year peak flow rate. It was assumed that a 2-foot dike would be constructed at the outletof Pond SC-30-1 to increase the storage volume for future conditions.SC-31: Pond SC-31-1 overflows to the southwest through a natural drainage swale into NewMarket Township. The mean depth of Pond SC-31-1 was assumed to be 3.6 feet, to obtain thedesired water quality removal efficiency for this subwatershed.SC-32: Pond SC-32-1 is a low area at 215th Street West, which overtops the road by 0.3 footduring the 100-year flood. 215th Street West is a gravel road, and was assumed to be raisedby at least 0.5 foot for future conditions. Construction of a 3-acre pond was assumed forfuture conditions, to reduce the 100-year peak flow rate.SC-33: Pond SC-33-1 is a low area located between I-35 and Keokuk Avenue. For proposedconditions, Pond SC-33-1 was assumed to be located west of Keokuk Avenue, and enlarged to4 acres to reduce the 100-year peak flow rate. Keokuk Avenue is currently a gravel road andwas assumed to be raised by at least 3 feet under future conditions.SC-35: Under existing conditions, runoff from this subwatershed flows south toSubwatershed SC-17. This subwatershed was subdivided for proposed conditions todetermine the peak flow rates into the proposed storm sewer system along Dodd Boulevardand 210th Street West. A 5-acre pond (Pond SC-35-1) was assumed to be constructed inSubwatershed SC-35A under future conditions to reduce the 100-year peak flow rate. Theproposed storm sewer system directs the runoff under the adjacent railroad tracks toSubwatershed SC-16.Lakeville Water Resources Management Plan Page 4-37

SC-43: Outflow from Marion Lake enters this subwatershed, which is the upstream end ofthe Marion Branch of South Creek. For the existing conditions analysis, the Marion Branchflowed east through a channel and storm sewer system through downtown to the confluencewith the West Branch of South Creek in Subwatershed SC-15. The high flows through thedowntown storm sewer system placed portions of the downtown area in the floodplain. In1994, a new storm sewer system was constructed that routes the Marion Branch flow southalong Dodd Boulevard and east along 210th Street West to Subwatershed SC-16.For proposed conditions, the Marion Branch was routed south and east in the new stormsewer system to Subwatershed SC-16. This removes the floodplain designation in thedowntown area. To prevent floodplain zoning problems along Dodd and 210th Street, thenew trunk storm sewer has capacity for 100-year flows from Lake Marion as well as 100-yearinflows from local areas.The outflow from Marion Lake was assumed to be the discharge at the lake level determinedfrom the frequency distribution for the lake. The lake level is shown to be above the outletelevation for flood frequencies greater than the 15-year flood. Therefore, the 2- and 10-yearfrequency events assume no Marion Lake outflow. The discharge for the 50-year flood wasassumed to be 30 cfs. The discharge for the 100-and 500-year floods was assumed to 40 and50 cfs, respectively.This subwatershed was subdivided for proposed conditions to account for proposed pondingareas. A 3-acre pond (Pond SC-43-2) was assumed to be constructed in Subwatershed SC-43C for proposed conditions. A 2-acre pond (Pond SC-43-3) was assumed to be constructedin Subwatershed SC-43B for proposed conditions. The low area at Dodd Boulevard(Pond SC-43-1) was enlarged to 1 acre for proposed conditions. These ponds will more thancompensate for channel storage in the existing ditch east of Dodd Boulevard.It was assumed that a 4-foot dike would be constructed at the outlet of Pond SC-43-2 toobtain the storage volume for future conditions.SC-44: A 2-acre pond was assumed to be constructed for proposed conditions, to reduce thedischarge downstream. It was assumed that a 4-foot dike would be constructed at the outletto obtain the storage volume.SC-73: For proposed conditions, it was assumed that the existing low area at Cedar Avenuewill be enlarged to 3 acres (Pond SC-73-1). To reduce peak flow rates, the existing outlet wasassumed to be replaced with a smaller outlet under Cedar Avenue.SC-75: For proposed conditions, it was assumed that the existing low area at County Road64 is enlarged to 2 acres (Pond SC-75-1). To reduce peak flow rates, the existing cattle passunder County Road 64 was assumed to be replaced with a smaller outlet.Lakeville Water Resources Management Plan Page 4-38

SC-76: For proposed conditions, it was assumed that the existing low area at County Road64 is enlarged to 2 acres (Pond SC-76-1). To reduce peak flow rates, the existing outlet underCounty Road 64 was assumed to be replaced with a smaller outlet.4.7 FARMINGTON OUTLET DISTRICTThe Farmington Outlet District is located east of Ipava Avenue and extends to the boundary withthe city of Farmington, between 202nd Street West and 175th Street West. The district lieswithin the Vermillion River Watershed, which is managed by the VRWJPO. Lakeville is amember of this Joint Powers Organization. There are no large surface water bodies within thisdistrict. Drainage from the Farmington Outlet District flows east in existing channels throughthe city of Farmington into the Vermillion River, which discharges to the Mississippi River.The City of Lakeville will begin the development of updated hydrologic and water quality modelsfor the city in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results and anyresulting flow or volume restrictions. The updated modeling will likely result in some changes inpond locations and volumes as well as changes for pipe sizing. As a result, this program will beupdated based on the updated model. This Water Resources Management Plan will then beupdated to include the new design program. In the interim, this section will continue to be thebasis for design of the city’s system needs.The watershed divides of the Farmington Outlet District are shown on Figure 4.7.1. Moredetail on the drainage system is shown on Figure 4.7.2.Runoff from Farmington Outlet District currently flows into the city of Farmington from ninedifferent subwatersheds. Subwatersheds FO-1, FO-4, FO-22, FO-27 and FO-28 are isolated subwatershedswhere runoff flows directly to the city of Farmington. Subwatersheds FO-2 and FO-3are a similar isolated pair of subwatershed.Drainage from this district flows in three main channels (located in FO-5, FO-16 and FO-23) tothe city of Farmington. In the FO-5 channel, drainage from west of Dodd Boulevard is collectedin the northern channel and flows directly east at 182nd Street West. The central channelcollects runoff from areas adjacent to 190th Street, and flows east through Subwatershed FO-16.Runoff from areas between 195th and 200th Street West is collected in the southern channel andflows east through Subwatershed FO-23.The Farmington Outlet District covers approximately 3,410 acres, which is currently mainlyagricultural land. Most of this district lies outside of the Metropolitan Urban Service Area(MUSA). The future land use is projected to be primarily low density residential. Compared tothe northern and western portions of the city there is a considerable relief in this district. ThisLakeville Water Resources Management Plan Page 4-39

elief has created a high density of swales and channels. The streams of the Farmington OutletDistrict all discharge to the Vermillion River below the city of Farmington.As the stream flows through the city of Farmington it passes through large wetlands but notthrough parks or other public recreational facilities. The Watershed Management Organizationhas not set any specific goals for water quality in this area. The Parks Department of the City ofLakeville has prepared a system vision plan that calls for ultimate creation of parks in FO-5 andFO-23 east of Cedar Avenue. Since Cedar Avenue will act to control rates of runoff and providesedimentation of stormwater, the wetlands in these areas should be managed for wildlife andaesthetic uses, with nutrient removal as a secondary use.In other areas, it appears that the most appropriate management goal would be to try to meetregional goals for reduction of nutrients as set by the Metropolitan Council and MPCA. This willinclude nutrient reduction either through construction of on-site basins or regional detentionbasins to meet NURP standards.4.7.1 PONDNET Modeling of Farmington Outlet DistrictThe water quality modeling results presented here were completed in 1993. The City ofLakeville will begin the development of updated hydrologic and water quality models for thecity in 2008. These updated models will account for changes that have occurred in thesystem over the last 13 years and will conform to the VRWJPO hydrologic model results.This Water Resources Management Plan will be updated to include the new model results.In the interim, this section will continue to be the basis for design of the city’s system needs.The City recently completed the Lakeville Ms4 Loading Assessment and Non DegradationReport, included as Appendix D. This report also provides a general citywide water qualitymodel and analyses.The existing land use within this district is mainly agricultural. For future conditions, thisdistrict is zoned as low density residential. The results of the existing and future conditionsPONDNET models for the Farmington Outlet District are tabulated in Table 4.7.1.All wetlands shown on the National Wetlands Inventory map are assumed to be preserved forproposed conditions and all stormwater ponds will be constructed with an average of at least3 feet of water quality storage (i.e., dead storage) below the runout elevation.4.7.2 Flood ProtectionFor each subwatershed and storage pond, peak runoff rates, flood levels, flood dischargesand storage volumes were calculated using the HEC-1 model as described in Appendix A.The results of the modeling are shown in the tables at the end of this section. Information isdescribed as follows:Lakeville Water Resources Management Plan Page 4-40

Table 4.7.2Table 4.7.3Table 4.7.4Table 4.7.5Table 4.7.6Table 4.7.7Existing Conditions—Hydraulic and hydrologicparameters (subwatershed data)Existing Conditions—Critical events and correspondingrunoff (peak flow rates from watersheds and ponds)Existing Conditions—Peak discharges and elevations(flood levels and outflows from ponds)Proposed Conditions—Hydraulic and hydrologicparameters (subwatershed data)Proposed Conditions—Critical events and correspondingrunoff (peak runoff rates and volumes from watersheds)Proposed Conditions—Peak discharges and elevations(flood levels and outflows from ponds)4.7.3 Subwatershed DescriptionsFor proposed conditions, desired 100-year flow rates into the city of Farmington wereobtained from the City of Farmington Comprehensive Storm Drainage Plan, 1985.The subwatersheds described in this section have unique characteristics or significantalterations from existing to proposed conditions.FO-2: The discharge from this subwatershed flows directly into the city of Farmington.Under future conditions, a 7-acre pond would be necessary to reduce the 100-year peak flowrate to the rate of 60 cfs assumed in the Farmington water management plan. This issignificantly below the existing 100-year flow rate and might be increased if conditions inFarmington do not require such a reduction. It was assumed that a 5-foot dike would beconstructed at the outlet of Pond FO-2-1 to increase the storage volume and decrease thepeak flow rate.FO-4: The discharge from this subwatershed flows directly into Farmington. To reduce the100-year peak flow rate for proposed conditions, a 2-acre pond was assumed. Again, thisreduces the flow rate to below existing conditions. It was assumed that a 4-foot dike could beconstructed at the outlet of Pond FO-4-1 to increase the storage volume.FO-5: The mean depth of the wetlands in this subwatershed was assumed to be excavated to3 feet, to obtain the desired removal efficiency for the channel.FO-10: To reduce the 100-year peak flow rate to downstream subwatersheds for proposedLakeville Water Resources Management Plan Page 4-41

conditions, the area of Pond FO-10-1 was enlarged to 3 acres.FO-14: For proposed conditions, a 3-acre pond was assumed at the outlet under DoddBoulevard, to reduce peak discharges to downstream subwatersheds.FO-16: The mean depth of the wetlands in this subwatershed was assumed to be excavatedto 3 feet, to obtain the desired removal efficiency for the channel.FO-18: The mean depth of the wetlands in this subwatershed was assumed to be excavatedto 3 feet, to obtain the desired removal efficiency for the channel.FO-19: Under existing conditions, Pond FO-19-1 overtops 190th Street West byapproximately 0.2 feet during the 10-year flood and 0.5 feet during the 100-year flood. Tolower the 100-year flood level for proposed conditions, the area of the pond was assumed tobe enlarged to 1 acre and the outlet capacity was assumed to be increased.FO-20: The area of Pond FO-20-1 was enlarged to 4 acres for proposed conditions, to lowerthe 100-year flow rate and increase the storage volume. Some of the required storage volumemay be obtained in the existing upstream wetlands, as long as the peak flow rate does notincrease.FO-21: The mean depth of the wetlands in this subwatershed was assumed to be excavatedto 3 feet, to obtain the desired removal efficiency for the channel.FO-22: The discharge from this subwatershed flows directly into the city of Farmington. Toreduce the 100-year peak flow rate for proposed conditions to meet the assumptions of theFarmington plan, a 1-acre pond was assumed. It was assumed that a 5-foot dike would beconstructed at the outlet of Pond FO-22-1 to increase the storage volume.FO-23: For proposed conditions, a 10-acre pond was assumed to be constructed for waterquality purposes. The pond would have minimal stormwater detention storage.FO-24: The volume of Pond FO-24-1 was enlarged slightly for proposed conditions, to lowerthe 100-year peak discharge in downstream subwatersheds. Some of the required storagevolume may be obtained in the existing upstream wetlands, as long as the peak flow rate doesnot increase. The mean depth of the wetlands in this subwatershed was assumed to beexcavated to 3 feet, to obtain the desired removal efficiency for the channel.FO-25: Under future conditions, a 2-acre pond will be necessary to reduce the 100-year peakflow rate to downstream subwatersheds.FO-27: The discharge from this subwatershed flows directly into the city of Farmington. Toreduce the 100-year peak flow rate for proposed conditions, a 3-acre pond was assumed. ItLakeville Water Resources Management Plan Page 4-42

was assumed that a 5-foot dike would be constructed at the outlet of Pond FO-27-1 toincrease the storage volume. Some of the required storage volume may be obtained in theexisting upstream wetlands, as long as the peak flow rate does not increase.FO-28: The discharge from this subwatershed flows directly into the city of Farmington. A1-acre pond was assumed for proposed conditions, to reduce the 100-year peak flow rate. Itwas assumed that a 3-foot dike would be constructed at the outlet of Pond FO-28-1 toincrease the storage volume.Lakeville Water Resources Management Plan Page 4-43

CONDITION AVERAGESURFACEINFLOWVOLUME(acre-feet)EXISTING CONDITIONS:Oak Shores ParkPondOak ShoresDrainage ChannelTable 4.2.1 Crystal Lake PONDNET ResultsESTIMATEDPHOSPHORUSLOAD(Pounds/Year)AVERAGEPHOSPHORUSCONCENTRATION (ppb)PERCENTTOTALPHOSPHORUSREMOVAL412 74 66 7650 44 319 51Bluebill Bay Pond 100 53 195 48Storm Sewer East 36 46 292 32of Illinois AvenueFUTURE CONDITIONS WITH EXISTING WETLANDS:Oak Shores Park 1,111 301 100 63PondBluebill Bay Pond 277 138 183 40PROPOSED CONDITIONS:Oak Shores Park 1,111 256 85 68PondBluebill Bay Pond 277 112 148 55Lakeville Water Resources Management Plan Page 4-44

CONDITIONTable 4.2.2 Lee Lake PONDNET ResultsAVERAGESURFACEINFLOWVOLUME(acre-feet)ESTIMATEDPHOSPHORUSLOAD(Pounds/Year)AVERAGEPHOSPHORUSCONCENTRATION (ppb)PERCENTTOTALPHOSPHORUSREMOVALExisting 125 29 84 73Future Conditions 205 44 79 71with ExistingWetlandsProposed 205 44 79 71Table 4.2.3 Predicted Discharges from Hydrologic ModelsLOCATION100-YEAR PEAK FLOW RATE (cfs)U.S.G.S.RegressionHEC-1 Inflow toMostHEC-1 Flow toCrystal LakeMethod DownstreamPondOak Shores Park Pond 213 190 67Oak Shores Drainage Channel 382 233 194Bluebill Bay Pond 251 159 68Storm Sewer East of Illinois Ave. 185 118 100Lee Lake 363 342 0Lakeville Water Resources Management Plan Page 4-45

Table 4.2.4 Crystal Lake District: Existing Conditions - Hydrologic and Hydraulic ParametersSUBWATERSHEDNAMEAREA(AC)HYDRAULIC METHODLENGTH (FT) USEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSCL-1A 73.7 38 100.0 53.2 38.2CL-1B 5.0 16 100.0 61.0 16.0CL-1C 6.6 22 100.0 52.4 21.8CL-2 53.0 1050 Kin 600 26 75.9 48.8 0.0 24.1 98.0 0.0CL-3 46.7 3200 Kin 120 16 89.0 52.6 0.0 11.0 98.0 0.0CL-4 31.6 2300 Kin 1600 15 89.8 61.1 0.0 10.2 98.0 0.0CL-5 25.4 1400 Kin 330 12 88.4 56.3 0.0 11.6 98.0 0.0CL-6 24.0 1900 Kin 1900 22 84.3 52.1 0.0 15.7 98.0 0.0CL-7 95.2 2100 Kin 200 20 81.9 53.2 0.0 18.1 98.0 0.0CL-8 152.0 4150 Kin 2300 35 73.4 61.0 0.0 26.6 98.0 0.0CL-9 23.6 1600 Kin 1750 18 87.1 62.0 0.0 12.9 98.0 0.0CL-10 95.4 1970 Kin 1100 31 71.3 62.0 0.0 28.7 98.0 0.0CL-11 26.1 SCS 0.41 2900 4 100.0 61.0 4.0CL-12 197.3 1600 Kin * 17 84.0 60.5 0.0 16.0 98.0 0.0CL-13 26.3 SCS 0.25 1100 14 100.0 60.0 14.0CL-14 61.2 SCS 0.65 * 2 100.0 57.0 2.0CL-15 23.1 SCS 0.23 4500 5 100.0 66.0 5.0CL-16 39.7 SCS 0.18 700 3 100.0 79.0 3.0CL-17 54.0 SCS 0.32 1300 2 100.0 65.0 2.0CL-18 105.9 2800 Kin 500 14 95.1 65.6 0.0 4.9 98.0 0.0CL-19 22.6 SCS 0.13 2400 12 100.0 71.0 12.0CL-20 17.2 SCS 0.80 2670 4 100.0 60.0 4.0CL-21 14.5 690 Kin 165 42 65.4 57.0 0.0 34.6 98.0 0.0CL-22 19.8 1350 Kin 200 30 79.0 59.2 0.0 21.0 98.0 0.0CL-23 11.0 1200 Kin 1770 34 75.4 62.2 0.0 24.6 98.0 0.0CL-24 12.7 1900 Kin 300 30 79.0 49.4 0.0 21.0 98.0 0.0CL-25 14.1 SCS 0.13 600 7 100.0 77.0 7.0CL-26 57.1 SCS 0.52 700 15 100.0 74.5 15.0CL-27 42.7 SCS 0.24 600 1 100.0 67.2 1.0CL-28A 20.9 1300 Kin 700 13 90.8 61.1 0.0 9.2 98.0 0.0CL-28B 17.8 SCS 0.12 1700 5 100.0 58.4 4.5CL-29 19.6 SCS 0.17 * 2 100.0 58.2 2.0CL-30 5.4 SCS 0.11 300 5 100.0 79.2 5.0CL-31 50.7 SCS 0.23 1200 1 100.0 76.2 1.0CL-32 17.1 1300 Kin 1300 32 76.2 62.0 0.0 23.8 98.0 0.0CL-33 30.6 2900 Kin 500 31 78.3 62.0 0.0 21.7 98.0 0.0CL-34 15.1 SCS 0.12 500 7 100.0 70.0 6.7* This subwatershed remains landlocked for this case.Lakeville Water Resources Management Plan Page 4-46

LOCATIONDESIGNATIONTable 4.2.5 Crystal Lake District: Existing Conditions - Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)CL-14 61.2 2 day 0.42 5 2 day 1.04 12 6 0.69 22 6 0.90 28 6 1.37 43CL-14-1 61.2 30 day 0 30 day 0 30 day 0 30 day 0 30 day 0CL-13 26.3 0.5 0.17 10 0.5 0.25 15 1 0.58 24 1 0.71 29 1 1.00 43CL-13-1 26.3 1 1 2 day 3 2 day 4 12 4 12 5CL-12 197.3 0.5 0.16 147 0.5 0.25 230 0.5 0.39 325 0.5 0.48 363 0.5 0.68 455CL-12-1 223.6 30 day 0 30 day 0 30 day 0 30 day 0 30 day 0CL-19 22.6 0.5 0.17 12 0.5 0.33 23 1 0.85 40 0.5 0.68 49 0.5 0.95 70CL-19-1 22.6 1 8 1 16 1 26 1 32 1 44CL-20 17.2 2 day 0.59 2 6 0.49 4 6 0.89 7 6 1.13 9 6 1.66 14104 39.8 1 8 1 16 1 27 1 34 1 47CL-18 105.9 0.5 0.05 22 6 0.70 44 1 0.50 84 1 0.64 119 1 0.96 206CL-17 54.0 2 day 0.74 9 6 0.61 19 1 0.42 35 1 0.56 47 1 0.86 73CL-17-1 199.7 2 day 33 6 76 6 127 6 152 6 216CL-16 39.7 1 0.30 23 1 0.63 50 1 1.03 83 1 1.24 101 1 1.70 140CL-16-1 39.7 1 17 1 41 1 71 1 87 1 120CL-15 23.1 1 0.11 4 1 0.28 11 1 0.52 21 1 0.67 27 1 0.99 41CL-15-1 262.5 2 day 22 6 102 6 186 6 223 1 306CL-11 26.1 6 0.21 3 6 0.52 7 6 0.94 14 6 1.19 17 1 0.74 26CL-11-1 26.1 2 day 3 6 5 6 9 6 11 6 15CL-10 95.4 0.5 0.28 127 0.5 0.44 205 0.5 0.64 283 0.5 0.76 327 0.5 1.01 404100 121.5 0.5 127 0.5 205 0.5 283 0.5 327 0.5 405CL-10-1 121.5 2 day 14 2 day 27 6 38 6 41 6 47CL-9 23.6 0.5 0.13 11 0.5 0.22 18 0.5 0.36 26 0.5 0.44 30 0.5 0.65 38101 145.1 2 day 16 6 32 6 50 6 56 6 67CL-8 152.0 1 0.35 115 0.5 0.41 191 0.5 0.59 278 0.5 0.70 321 0.5 0.94 417CL-8-1 152.0 6 15 2 day 24 2 day 71 2 day 88 6 143CL-7 95.2 0.5 0.18 57 0.5 0.26 95 0.5 0.36 135 0.5 0.43 158 0.5 0.58 198CL-6 24.0 0.5 0.15 18 0.5 0.23 28 0.5 0.31 39 0.5 0.37 44 0.5 0.51 56CL-5 25.4 0.5 0.11 12 0.5 0.17 20 0.5 0.26 28 0.5 0.33 32 0.5 0.48 40CL-5-1 441.7 2 day 37 2 day 59 2 day 128 2 day 189 6 288CL-4 31.6 0.5 0.10 9 0.5 0.17 15 0.5 0.29 22 0.5 0.37 25 0.5 0.56 33CL-4-1 31.6 6 1 2 day 3 2 day 4 2 day 5 2 day 7CL-3 46.7 0.5 0.11 18 0.5 0.16 29 0.5 0.22 42 0.5 0.27 49 0.5 0.39 60CL-3-1 782.5 2 day 40 2 day 111 6 190 2 day 291 6 500CL-2 53.0 0.5 0.24 64 0.5 0.35 100 0.5 0.47 138 0.5 0.53 158 0.5 0.68 193CL-2-1 835.5 2 day 27 2 day 51 2 day 69 2 day 73 2 day 80CL-34 15.1 1 0.18 5 1 0.40 12 1 0.70 23 1 0.87 29 1 1.24 42CL-33 30.6 0.5 0.21 30 0.5 0.34 47 0.5 0.52 67 0.5 0.62 74 0.5 0.85 93CL-33-1 45.7 1 9 6 18 6 30 6 36 1 58CL-32 17.1 0.5 0.23 18 0.5 0.37 29 0.5 0.55 41 0.5 0.66 47 0.5 0.90 59RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-47

LOCATIONDESIGNATIONTable 4.2.5 Crystal Lake District: Existing Conditions - Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)CL-32-1 62.8 6 9 6 20 6 31 6 37 6 56CL-31 50.7 1 0.20 19 1 0.49 45 1 0.85 79 1 1.05 98 1 1.47 139CL-30 5.4 1 0.33 4 0.5 0.42 8 0.5 0.70 14 0.5 0.86 17 0.5 1.20 24CL-31-1 118.9 6 15 2 day 49 6 78 1 100 1 158CL-28B 17.8 0.5 0.05 3 0.5 0.08 5 1 0.31 10 1 0.41 14 1 0.65 24CL-28-1 17.8 0.5 2 1 4 1 9 1 12 1 20CL-28A 20.9 1 0.12 6 0.5 0.16 9 0.5 0.28 14 0.5 0.35 16 0.5 0.54 20108 38.7 0.5 8 0.5 11 0.5 16 0.5 18 1 28CL-26 57.1 1 0.36 23 1 0.67 44 1 1.04 69 1 1.24 82 1 1.68 112109 95.8 1 25 1 48 1 78 1 95 1 133CL-27 42.7 2 day 0.81 8 6 0.68 18 1 0.47 36 1 0.62 47 1 0.94 73CL-25 14.1 0.5 0.18 8 1 0.61 19 1 1.00 31 0.5 0.80 38 0.5 1.12 53CL-25-1 152.6 6 35 6 69 6 105 6 125 6 159110 152.6 6 35 6 69 6 105 6 125 6 159CL-23 11.0 0.5 0.24 12 0.5 0.38 20 0.5 0.57 27 0.5 0.68 31 0.5 0.92 39CL-23-1 11.0 1 5 1 7 1 9 1 10 0.5 12CL-22 19.8 0.5 0.21 19 0.5 0.32 31 0.5 0.47 43 0.5 0.56 48 0.5 0.77 61CL-24 12.7 0.5 0.21 12 0.5 0.31 20 0.5 0.41 27 0.5 0.47 31 0.5 0.61 39CL-21 14.5 0.5 0.34 27 0.5 0.51 41 0.5 0.70 57 0.5 0.81 63 0.5 1.05 76CL-21-1 210.6 2 day 21 2 day 40 2 day 53 2 day 68 6 134CL-29 19.6 2 day 0.46 2 2 day 1.11 5 1 0.24 9 1 0.33 13 1 0.56 22CL-29-1 19.6 30 day 0 30 day 0 30 day 0 30 day 0 30 day 0RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-48

Table 4.2.6 Crystal Lake District: Existing Conditions - Peak Discharges and ElevationsPONDNAMENWL(MSL)PEAK ELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAK ELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)CL-2-1 937.3 939.7 13.2 27 941.1 34.5 51 942.8 61.9 69 944.0 84.5 73 946.1 135.9 80CL-3-1 938.2 940.0 0.6 40 943.6 3.7 111 945.8 6.4 190 946.9 8.2 291 949.0 11.8 500CL-4-1 1008.6 1008.8 1.1 1 1009.1 2.2 3 1009.4 3.5 4 1009.5 4.3 5 1009.9 5.8 7CL-5-1 943.0 945.4 3.9 37 947.8 9.8 59 949.7 16.0 128 950.0 16.8 189 950.1 17.6 288CL-8-1 983.0 984.8 4.4 15 986.2 8.4 24 987.4 12.3 71 987.5 12.4 88 987.5 12.6 143CL-10-1 998.7 1000.4 3.4 14 1001.3 5.4 27 1002.4 7.9 38 1003.1 9.7 41 1004.6 13.9 47CL-11-1 1003.7 1004.3 0.2 3 1004.7 0.4 5 1005.2 0.7 9 1005.6 1.0 11 1006.2 1.5 15CL-12-1 946.1 ** ** 0 ** ** 0 ** ** 0 953.1 167.7 0 ** ** 0CL-13-1 964.6 965.2 0.9 1 965.8 1.8 3 966.4 2.9 4 966.7 3.5 4 967.4 4.8 5CL-14-1 992.9 ** ** 0 ** ** 0 ** ** 0 1006.6 45.9 0 ** ** 0CL-15-1 959.5 963.7 5.1 22 964.2 5.9 102 964.3 6.3 186 964.4 6.4 223 964.5 6.7 306CL-16-1 975.8 976.1 6.2 17 976.2 6.5 41 976.3 6.7 71 976.4 6.8 87 976.5 7.1 120CL-17-1 986.7 988.3 0.1 33 990.4 0.1 76 992.9 0.5 127 994.2 1.1 152 996.1 2.7 216CL-19-1 1090.5 1090.6 5.9 8 1090.7 6.1 16 1090.8 6.3 26 1090.8 6.4 32 1090.9 6.7 44CL-21-1 933.8 936.3 6.2 21 938.1 11.2 40 940.1 17.7 53 940.9 20.6 68 942.2 25.2 134CL-23-1 953.9 955.1 0.1 5 955.3 0.2 7 955.5 0.2 9 955.6 0.3 10 955.8 0.3 12CL-25-1 957.3 959.5 0.2 35 961.0 0.7 69 962.5 1.6 105 963.4 2.3 125 965.3 4.2 159CL-28-1 1074.0 1075.0 0.0 2 1075.8 0.0 4 1076.2 0.1 9 1076.4 0.1 12 1076.9 0.2 20CL-29-1 1066.5 ** ** 0 ** ** 0 ** ** 0 1081.2 14.7 0 ** ** 0CL-31-1 952.5 958.4 1.2 15 960.0 2.3 49 960.1 2.4 78 960.2 2.4 100 960.3 2.6 158CL-32-1 972.5 973.9 0.9 9 974.7 1.6 20 975.7 2.4 31 976.2 2.9 37 977.1 3.8 56CL-33-1 974.5 975.8 0.5 9 976.6 0.9 18 977.5 1.4 30 978.1 1.7 36 979.1 2.3 58** This pond remains landlocked for this case. The critical event is the 30-day snowmelt, which is shown for the 100-year frequency event. Otherfrequency events were not determined for landlocked basins.Lakeville Water Resources Management Plan Page 4-49

Table 4.2.7 Crystal Lake District East: Proposed Plan 1 – Hydrologic and Hydraulic ParametersSUBWATERSHEDNAMEAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSCL-21 14.5 690 Kin 165 42 65.4 57.0 0.0 34.6 98.0 0.0CL-22 19.8 1350 Kin 200 30 79.0 59.2 0.0 21.0 98.0 0.0CL-23 11.0 1200 Kin 1770 34 75.4 62.2 0.0 24.6 98.0 0.0CL-24 12.7 1900 Kin 300 30 79.0 49.4 0.0 21.0 98.0 0.0CL-25A 1.6 SCS 0.03 800 0 100.0 74.0 0.0CL-25B 2.1 SCS 0.05 60 0 100.0 74.0 0.0CL-26A 21.6 1100 Kin 400 30 79.0 1 62.0 0.0 21.0 1 98.0 0.0CL-26B 35.5 1600 Kin 550 46 57.2 58.8 0.0 42.8 98.0 0.0CL-27 12.8 2300 Kin 170 7 94.4 74.2 0.0 5.6 98.0 0.0CL-28A 25.3 1300 Kin 700 30 79.0 63.8 0.0 21.0 98.0 0.0CL-28B 17.8 1200 Kin 1700 30 79.0 62.0 0.0 21.0 98.0 0.0CL-29 19.6 700 Kin 1100 33 75.4 62.0 0.0 24.6 98.0 0.0CL-30 37.6 1800 Kin 240 25 79.8 74.8 0.0 20.2 98.0 0.0CL-31A 20.9 2000 Kin 1400 15 89.8 74.4 0.0 10.2 98.0 0.0CL-31B 3.1 SCS 0.06 2300 100.0 74.0 0.0CL-31C 23.1 1500 Kin 240 23 83.9 74.7 0.0 16.1 98.0 0.0CL-32 17.1 1300 Kin 1300 32 76.2 62.0 0.0 23.8 98.0 0.0CL-33 30.6 2900 Kin 340 31 78.3 62.0 0.0 21.7 98.0 0.0CL-34 15.1 2400 Kin 1000 30 79.0 62.0 0.0 21.0 98.0 0.01 For Plan 2, the percent of watershed in the pervious flow plane is 44.0 and 56.0 in the impervious flow plane (70 percent Composite Impervious).Lakeville Water Resources Management Plan Page 4-50

LOCATIONDESIGNATIONTable 4.2.8 Crystal Lake District East: Proposed Plan 1 – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)CL-34 15.1 0.5 0.21 18 0.5 0.33 27 0.5 0.50 36 0.5 0.61 40 0.5 0.83 49CL-33 30.6 0.5 0.21 30 0.5 0.34 47 0.5 0.52 67 0.5 0.62 74 0.5 0.85 93CL-33-1 30.6 1 7 6 11 6 18 6 23 1 32CL-32 17.1 0.5 0.23 18 0.5 0.37 30 0.5 0.55 42.00 0.5 0.66 48 0.5 0.90 60CL-32-1 62.8 6 9 6 19 6 30 6 36 6 56CL-31C 23.1 0.5 0.22 16 0.5 0.43 26 0.5 0.69 38 0.5 0.84 43 0.5 1.15 56CL-31-3 23.1 6 4 6 9 6 14 6 19 6 29CL-31B 3.1 0.5 0.06 1 0.5 0.21 3 0.5 0.43 6 0.5 0.55 8 0.5 0.83 12CL-31-2 26.2 6 3 6 5 6 7 12 10 6 17CL-31A 20.9 0.5 0.16 9 0.5 0.35 15 3 1.44 23 1 1.12 29 1 1.54 47CL-31-1 47.1 12 6 6 9 12 13 6 15 12 27112 105.4 12 13 6 26 6 40 6 48 6 68CL-29 19.6 0.5 0.24 23 0.5 0.38 37 0.5 0.57 51 0.5 0.68 58 0.5 0.92 72CL-29-1 19.6 0.5 2 3 4 6 6 6 7 6 8CL-28B 17.8 0.5 0.21 18 0.5 0.33 29 0.5 0.50 41 0.5 0.61 46 0.5 0.83 57107 37.4 0.5 18 0.5 29 0.5 40 0.5 46 0.5 58CL-28A 25.3 0.5 0.21 15 0.5 0.34 26 0.5 0.53 38 0.5 0.64 43 0.5 0.88 56108 62.7 0.5 30 0.5 49 0.5 72 0.5 83 0.5 106CL-26B 35.5 0.5 0.41 28 0.5 0.61 44 0.5 0.83 61 0.5 0.96 71 0.5 1.23 89CL-26A 21.6 0.5 0.21 23 0.5 0.33 35 0.5 0.50 49 0.5 0.61 55 0.5 0.83 68109 119.8 0.5 102 0.5 165 0.5 235 0.5 270 0.5 338CL-30 37.6 0.5 0.26 33 0.5 0.48 53 0.5 0.75 77 0.5 0.91 87 0.5 1.23 112CL-30-1 37.6 6 11 6 22 6 36 6 43 1 57CL-25B 2.1 0.5 0.06 1 0.5 0.21 2 0.5 0.43 4 0.5 0.55 5 0.5 0.83 8CL-25-2 39.7 6 10 6 23 6 37 6 45 1 57CL-27 13.8 6 0.55 4 6 1.10 9 3 1.34 15 1 1.02 19 1 1.44 31CL-27-1 13.8 0 0 12 1 24 3 12 6CL-25A 1.6 1 0.15 1 0.5 0.21 2 0.5 0.43 3 0.5 0.55 4 0.5 0.83 7CL-25-1 55.1 12 7 6 18 6 30 6 37 6 56110 293.8 0.5 105 0.5 170 0.5 240 0.5 277 0.5 348CL-23 11.0 0.5 0.24 12 0.5 0.38 20 0.5 0.57 27 0.5 0.68 31 0.5 0.92 39CL-23-1 11.0 1 5 1 7 1 9 1 10 0.5 12CL-22 19.8 0.5 0.21 19 0.5 0.32 31 0.5 0.47 43 0.5 0.56 48 0.5 0.77 61CL-24 12.7 0.5 0.21 12 0.5 0.31 20 0.5 0.41 27 0.5 0.47 31 0.5 0.61 39111 43.5 0.5 32 0.5 51 0.5 70 0.5 79 0.5 98CL-21 14.5 0.5 0.34 27 0.5 0.51 41 0.5 0.70 57 0.5 0.81 63 0.5 1.05 76CL-21-1 351.8 12 29 12 47 12 85 12 138 6 226For Plan 2, changes to the critical events, runoff and flow rates include:CL-26A 21.6 0.5 0.55 40 0.5 0.83 66 0.5 1.14 96 0.5 1.30 112 0.5 1.64 145CL-26-1 21.6 1 13 1 19 1 25 1 29 1 33RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-51

LOCATIONDESIGNATIONTable 4.2.8 Crystal Lake District East: Proposed Plan 1 – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)109 119.8 0.5 87 0.5 141 0.5 202 0.5 231 0.5 294110 293.8 0.5 91 0.5 147 0.5 210 0.5 240 0.5 304CL-21-1 351.8 12 31 12 49 12 93 12 146 6 242RUNOFF(IN)PEAKFLOW(CFS)Table 4.2.9 Crystal Lake District East: Proposed Plan 1 – Peak Discharges and ElevationsPONDNAMENWL(MSL)PEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV. (FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAK STORAGEELEV. (FT) VOLUME(AC-FT)PEAKFLOW(CFS)PEAK STORAGEELEV. (FT) VOLUME(AC-FT)PEAKFLOW(CFS)CL-21-1 933.8 937.1 8.2 29 939.5 15.6 47 941.8 23.9 85 942.2 25.3 138 942.5 26.6 226CL-23-1 953.9 955.1 0.1 5 955.3 0.2 7 955.5 0.2 9 955.6 0.3 10 955.8 0.3 12CL-25-1 967.0 968.0 0.7 7 968.7 1.1 18 969.3 1.6 30 969.6 1.8 37 970.1 2.1 56CL-25-2 967.0 969.7 1.1 10 969.9 1.2 23 970.1 1.3 37 970.2 1.3 45 970.4 1.3 57CL-27-1 965.5 970.0 0.9 0 971.0 1.8 0 972.0 2.6 1 972.1 2.7 3 972.3 2.9 6CL-29-1 1070.0 1070.9 1.4 2 1071.7 1.9 4 1072.6 2.4 6 1073.0 2.7 7 1074.0 3.4 8CL-30-1 971.0 972.2 0.6 11 972.9 1.0 22 973.6 1.4 36 973.9 1.6 43 974.8 2.2 57CL-31-1 955.6 956.8 0.8 6 957.6 1.4 9 958.4 2.1 13 958.8 2.4 15 959.7 3.4 27CL-31-2 964.0 965.2 0.6 3 966.5 1.4 5 967.9 2.4 7 968.4 2.6 10 968.9 3.0 17CL-31-3 973.0 974.2 1.1 4 975.0 1.6 9 975.9 2.1 14 976.2 2.4 19 976.6 2.7 29CL-32-1 972.5 973.9 0.9 9 974.6 1.5 19 975.6 2.3 30 976.1 2.8 36 977.1 3.8 56CL-33-1 974.5 975.6 0.4 7 976.1 0.6 11 976.6 1.0 18 976.9 1.1 23 977.8 1.5 32For Plan 2, the peak discharges, storage volumes and elevations changes include:CL-21-1 933.8 937.3 8.8 31 939.8 16.5 49 942.0 24.6 93 942.2 25.4 146 942.5 26.7 242CL-26-1 990.0 991.9 0.7 13 992.7 1.0 19 993.5 1.4 25 994.0 1.6 29 994.9 2.1 33Lakeville Water Resources Management Plan Page 4-52

SUBWATERSHEDNAMETable 4.2.10 Crystal Lake District West: Proposed Case 6 – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSIMPERVIOUS FLOW PLANEPERCENT OFWATERSHEDCURVENUMBERPERCENTIMPERVIOUSCL-1A 73.7 41 66.7 55.4 0.0 33.3 98.0 0.0CL-1B 5.0 34 75.5 63.1 0.0 24.5 98.0 0.0CL-1C 6.1 30 76.7 53.2 0.0 23.3 98.0 0.0CL-2 53.0 1150 Kin 600 43 64.2 50.4 0.0 35.8 98.0 0.0CL-3 46.7 2300 Kin 120 30 78.8 56.7 0.0 21.2 98.0 0.0CL-4A 13.1 3500 Kin 500 14 88.3 56.6 0.0 11.7 98.0 0.0CL-4B 34.6 3500 Kin 1100 30 79.0 63.7 0.0 21.0 98.0 0.0CL-5 25.4 1400 Kin 1000 40 68.7 58.8 0.0 31.3 98.0 0.0CL-6 24.0 1800 Kin 1900 30 79.0 54.6 0.0 21.0 98.0 0.0CL-7A1 25.1 800 Kin 400 50 54.4 59.2 0.0 45.6 98.0 0.0CL-7A2 7.0 700 Kin 1200 66 40.6 63.7 0.0 59.4 98.0 0.0CL-7B 21.2 1200 Kin 1000 55 53.1 52.6 0.0 46.9 98.0 0.0CL-7C 36.2 1300 Kin 300 70 37.0 57.1 0.0 63.0 98.0 0.0CL-8A 8.9 800 Kin 350 54 50.1 53.6 0.0 49.9 98.0 0.0CL-8B 166.9 3850 Kin 350 40 71.5 60.1 0.0 28.5 98.0 0.0CL-9 23.6 1600 Kin 900 41 67.1 63.1 0.0 32.9 98.0 0.0CL-10 95.4 2190 Kin 1100 50 57.9 63.5 0.0 42.1 98.0 0.0CL-11 26.1 2790 Kin 1400 54 55.4 65.0 0.0 44.6 98.0 0.0CL-12A 183.4 1600 Kin 3500 48 51.9 60.8 0.0 48.1 98.0 0.0CL-12B 7.4 500 Kin 1100 36 72.6 63.0 0.0 27.4 98.0 0.0CL-13 26.3 1200 Kin 500 34 74.2 63.0 0.0 25.8 98.0 0.0CL-14A 36.9 1900 Kin 350 32 77.1 58.2 0.0 22.9 98.0 0.0CL-14B 13.3 900 Kin 1300 32 46.1 64.1 0.0 53.9 98.0 0.0CL-15 23.1 1600 Kin 1100 30 79.0 62.0 0.0 21.0 98.0 0.0CL-16 39.7 1100 Kin 700 30 79.0 63.0 0.0 21.0 98.0 0.0CL-17 54.0 2300 Kin 1300 30 79.0 63.0 0.0 21.0 98.0 0.0CL-18 89.8 3000 Kin 500 31 77.4 63.4 0.0 22.6 98.0 0.0CL-19 and CL-20 39.8 1500 Kin 2400 33 75.5 64.0 0.0 24.5 98.0 0.0Lakeville Water Resources Management Plan Page 4-53

LOCATIONDESIGNATIONTable 4.2.11 Crystal Lake District West: Proposed Case 6 – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICAL RUNOFFEVENT (HR) (IN)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARPEAKFLOW(CFS)CRITICALEVENT (HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)CL-14B 13.3 0.5 0.53 42 0.5 0.81 61 0.5 1.12 83 0.5 1.28 95 0.5 1.62 116CL-14-2 13.3 3 3 1 4 3 6 3 7 1 7CL-14A 36.9 0.5 0.33 64 0.5 0.51 100 0.5 0.72 139 0.5 0.84 155 0.5 1.09 191CL-14-1 50.2 1 5 6 7 3 8 3 8 3 9CL-13 26.3 0.5 0.25 39 0.5 0.41 58 0.5 0.60 80 0.5 0.72 87 0.5 0.97 109CL-13-1 26.3 12 2 6 3 6 4 2 day 5 12 6CL-12B 7.4 0.5 0.27 12 0.5 0.43 18 0.5 0.63 24 0.5 0.75 27 0.5 1.00 32CL-12-2 7.4 1 1 0.5 1 3 2 1 2 3 3CL-12A 183.4 0.5 0.47 508 0.5 0.71 747 0.5 0.98 1035 0.5 1.13 1135 0.5 1.44 1421CL-12-1 217.1 4 day 0 4 day 0 4 day 0 4 day 0 4 day 0CL-19 and CL-20 39.8 0.5 0.24 51 0.5 0.39 80 0.5 0.60 108 0.5 0.71 122 0.5 0.96 149CL-19-1 39.8 2 day 4 6 7 3 7 12 8 3 8CL-18 89.8 0.5 0.22 104 0.5 0.36 164 0.5 0.55 224 0.5 0.66 251 0.5 0.91 313105 145.7 0.5 105 0.5 165 0.5 225 0.5 252 0.5 314CL-18-1 128.6 2 day 10 2 day 17 2 day 22 2 day 23 2 day 27CL-17 54.0 0.5 0.21 58 0.5 0.34 91 0.5 0.52 126 0.5 0.62 141 0.5 0.86 174106 199.7 0.5 59 0.5 92 0.5 124 0.5 140 0.5 175CL-16 39.7 0.5 0.21 44 0.5 0.34 69 0.5 0.52 92 0.5 0.62 103 0.5 0.86 130CL-16-1 39.7 12 3 2 day 6 12 9 12 10 2 day 13CL-15 23.1 0.5 0.21 25 0.5 0.33 40 0.5 0.50 54 0.5 0.61 60 0.5 0.83 74CL-15-1 245.4 2 day 12 2 day 22 2 day 29 2 day 32 2 day 54113 245.4 2 day 12 2 day 22 2 day 29 2 day 32 2 day 54114 0 0 0 0 0CL-11 26.1 0.5 0.44 45 0.5 0.68 74 0.5 0.96 106 0.5 1.11 120 0.5 1.43 154CL-11-1 26.1 1 9 1 13 6 16 3 17 6 20CL-10 95.4 0.5 0.42 132 0.5 0.64 218 0.5 0.90 314 0.5 1.04 365 0.5 1.35 473100 121.5 0.5 136 0.5 224 0.5 322 0.5 374 0.5 483CL-10-1 121.5 6 23 6 38 6 44 6 47 6 53CL-9 23.6 0.5 0.32 40 0.5 0.51 63 0.5 0.73 86 0.5 0.86 96 0.5 1.13 118101 145.1 0.5 40 0.5 63 0.5 86 0.5 96 0.5 119CL-7B 21.2 0.5 0.46 43 0.5 0.68 68 0.5 0.91 98 0.5 1.04 108 0.5 1.30 140102 166.3 0.5 80 0.5 128 0.5 179 0.5 204 0.5 258CL-7-2 166.3 12 21 12 33 12 41 12 43 2 day 52CL-7C 36.2 0.5 0.62 99 0.5 0.92 156 0.5 1.24 226 0.5 1.40 247 0.5 1.75 321CL-6 24.0 0.5 0.21 26 0.5 0.31 41 0.5 0.43 56 0.5 0.50 63 0.5 0.68 77CL-5 25.4 0.5 0.31 42 0.5 0.46 66 0.5 0.66 88 0.5 0.77 99 0.5 1.01 124CL-5-1 497.3 12 25 2 day 41 2 day 56 2 day 63 2 day 88CL-4A 13.1 1 0.15 6 0.5 0.17 10 0.5 0.27 14 0.5 0.33 16 0.5 0.49 20CL-4-1 13.1 2 day 0 6 1 2 day 2 24 2 2 day 3CL-4B 34.6 0.5 0.21 33 0.5 0.34 53 0.5 0.53 73 0.5 0.64 81 0.5 0.88 101PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-54

LOCATIONDESIGNATIONTable 4.2.11 Crystal Lake District West: Proposed Case 6 – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT (HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT (HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)PEAKFLOW(CFS)CRITICAL RUNOFFEVENT (HR) (IN)CL-3 46.7 0.5 0.21 49 0.5 0.31 77 0.5 0.45 105 0.5 0.53 117 0.5 0.72 146103 94.4 0.5 80 0.5 127 0.5 175 0.5 197 0.5 244CL-3-2 94.4 6 7 12 11 2 day 13 2 day 14 2 day 16CL-3-1 591.7 2 day 46 2 day 77 2 day 100 2 day 111 2 day 138CL-8B 166.9 0.5 0.28 239 0.5 0.43 378 0.5 0.62 515 0.5 0.73 574 0.5 0.97 721CL-8-1 166.9 24 5 2 day 7 2 day 8 4 day 14 4 day 9CL-8A 8.9 0.5 0.44 27 0.5 0.65 42 0.5 0.89 57 0.5 1.02 63 0.5 1.30 77CL-8-2 189.8 2 day 5 2 day 7 2 day 8 2 day 9 4 day 11CL-7A1 25.1 0.5 0.48 65 0.5 0.72 101 0.5 0.98 134 0.5 1.12 150 0.5 1.43 183CL-7-1 214.2 2 day 6 2 day 8 2 day 9 2 day 10 2 day 11CL-7A2 7.0 0.5 0.59 22 0.5 0.88 35 0.5 1.21 47 0.5 1.38 52 0.5 1.74 64CL-2 53.0 0.5 0.35 99 0.5 0.52 156 0.5 0.69 211 0.5 0.79 235 0.5 1.00 294CL-2-1 869.8 2 day 36 2 day 60 2 day 74 2 day 77 2 day 81PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-55

PONDNAMENWL(MSL)Table 4.2.12 Crystal Lake District West: Proposed Case 6 – Peak Discharges and ElevationsPEAKELEV. (FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV. (FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV. (FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV. (FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV. (FT)STORAGEVOLUME(AC-FT)CL-2-1 937.8 940.2 27.7 36 941.4 46.8 60 942.6 67.1 74 943.3 80.3 77 944.9 111.6 81CL-3-1 938.2 940.3 0.2 46 941.8 0.5 77 943.0 1.0 100 943.6 1.2 111 944.5 1.8 138CL-3-2 947.2 949.2 1.8 7 950.9 4.0 11 952.5 7.6 13 953.1 9.7 14 954.4 14.2 16CL-4-1 1008.6 1008.7 0.4 0 1008.8 0.8 1 1008.9 1.3 2 1008.9 1.6 2 1009.1 2.2 3CL-5-1 943.0 945.0 4.9 25 946.0 8.2 41 947.0 11.1 56 947.5 12.6 63 948.3 15.1 88CL-7-1 970.0 971.7 3.4 6 972.4 4.9 8 973.2 6.6 9 973.9 8.3 11 974.5 9.7 11CL-7-2 972.0 974.0 4.7 21 975.9 8.3 33 977.7 12.1 41 978.5 13.9 43 980.1 17.7 52CL-8-1 972.0 979.7 19.1 5 984.1 34.4 7 988.3 52.5 8 990.1 61.1 14 990.6 63.8 45CL-8-2 970.0 971.7 2.5 5 972.4 3.8 7 973.2 5.2 8 973.9 6.2 10 974.5 6.6 11CL-10-1 998.7 1001.0 4.8 23 1002.2 7.4 38 1003.6 11.2 44 1004.4 13.3 47 1006.0 17.9 53CL-11-1 1003.7 1005.2 0.7 9 1005.9 1.1 13 1006.3 1.7 16 1006.6 2.1 17 1007.1 3.1 20CL-12-1 947.0 * * 0 * * 0 * * 0 951.9 116.1 43 * * 0CL-12-2 991.0 991.3 0.3 1 991.6 0.5 1 991.9 0.7 2 992.0 0.9 2 992.3 1.1 3CL-13-1 964.6 965.5 1.3 2 966.1 2.3 3 966.7 3.5 4 967.0 4.2 5 967.7 5.6 6CL-14-1 992.0 993.8 1.2 5 994.8 2.1 7 996.0 3.5 8 996.6 4.3 8 998.0 6.2 9CL-14-2 1026.5 1028.1 0.8 3 1028.9 1.2 4 1029.9 1.6 6 1030.3 1.9 7 1031.2 2.5 7CL-15-1 959.0 960.8 3.8 13 961.8 6.1 22 962.9 8.6 28 963.5 10.1 31 964.2 11.8 39CL-16-1 972.0 972.9 1.9 2 973.6 3.4 4 974.5 5.3 6 974.9 6.3 7 975.8 8.5 8CL-17-2 1003.0 1004.2 2.6 3 1005.2 4.8 5 1006.4 7.4 7 1007.0 8.9 8 1008.3 12.1 10CL-18-1 992.0 994.0 3.7 10 995.9 7.5 17 997.8 11.5 22 998.7 13.8 23 1000.4 18.7 27CL-19-1 1085.5 1086.8 1.9 4 1088.1 3.0 7 1089.5 4.7 7 1090.2 5.7 8 1091.6 8.0 8*This pond assumed to be equipped with a gated outlet for proposed conditions. The critical 100-year frequency event is considered to bethe 4-day event.PEAKFLOW(CFS)CONDITIONTable 4.3.1 Orchard Lake PONDNET ResultsAVERAGESURFACEINFLOWVOLUME(acre-feet)ESTIMATEDPHOSPHORUSLOAD(Pounds/Year)AVERAGEPHOSPHORUSCONCENTRATION (ppb)PERCENTTOTALPHOSPHORUSREMOVALExisting 355 59 61 86Future Conditions with Existing Wetlands 1,795 245 50 81Proposed 1,795 235 48 82Lakeville Water Resources Management Plan Page 4-56

SUBWATERSHEDNAMETable 4.3.2 Orchard Lake District: Existing Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBEROL-1 424.8 1000 Kin 200 56 45.1 66.1 0.0 54.9 98.0 0.0OL-2 105.5 SCS 0.76 60 4 100.0 56.0 4.0OL-3 76.8 SCS 0.10 300 13 100.0 67.0 13.0OL-4A 61.5 SCS 0.67 200 2 100.0 52.0 2.0OL-4B 68.9 SCS 0.20 1700 5 100.0 82.5 5.0OL-5 27.7 SCS 0.30 300 0 100.0 65.0 0.0OL-6 90.9 SCS 0.60 1600 5 100.0 77.0 5.0OL-7 75.3 SCS 0.30 1000 5 100.0 66.0 5.0OL-8 61.3 SCS 0.37 100 5 100.0 60.3 4.6OL-9 154.1 SCS 1.10 300 2 100.0 59.1 2.3OL-10 32.3 1100 Kin 3080 25 80.5 62.2 0.0 19.5 98.0 0.0OL-11 61.0 SCS 0.82 4200 5 100.0 74.5 5.0OL-12A 56.6 2400 Kin 200 44 62.2 61.5 0.0 37.8 98.0 0.0OL-12B 22.6 700 Kin 1100 32 69.8 58.8 0.0 30.2 98.0 0.0OL-13 122.6 SCS 0.71 1400 5 100.0 61.0 5.0OL-14 36.5 SCS 0.68 2100 21 100.0 61.5 20.5OL-15 63.4 1500 Kin 1100 15 89.6 62.2 0.0 10.4 98.0 0.0OL-16A 27.6 SCS 0.12 500 11 100.0 55.1 11.1OL-16B 34.0 1900 Kin 500 30 74.0 58.4 0.0 26.0 98.0 0.0OL-17A 58.2 2100 Kin 800 17 86.6 65.3 0.0 13.4 98.0 0.0OL-17B1 19.3 1500 Kin 600 37 66.3 60.2 0.0 33.7 98.0 0.0OL-17B2 23.2 1500 Kin 600 57 47.6 62.1 0.0 52.4 98.0 0.0OL-18A 7.5 SCS 0.06 50 12 100.0 56.1 12.1OL-18B 7.1 SCS 0.11 250 12 100.0 58.4 12.3OL-18C 11.6 450 Kin 1700 14 90.6 62.4 0.0 9.5 98.0 0.0OL-18D 3.3 SCS 0.02 400 12 100.0 55.6 12.0OL-19 21.6 600 Kin 600 13 88.9 61.4 0.0 11.1 98.0 0.0OL-20 61.2 1200 Kin 400 13 90.9 60.7 0.0 9.1 98.0 0.0OL-21 55.2 SCS 0.16 1300 31 100.0 52.1 3.0OL-22 41.4 1400 Kin 630 25 80.7 60.5 0.0 19.3 98.0 0.0OL-23 46.7 SCS 0.44 1700 10 100.0 57.2 10.0OL-24 47.0 1400 Kin 100 5 96.7 63.8 0.0 3.3 98.0 0.0OL-25 220.6 * 30 100.0 59.9 30.5OL-26 32.7 SCS 0.30 600 27 100.0 58.1 26.6OL-27 74.6 * 7 100.0 58.3 6.7OL-28 113.3 *** 13 100.0 58.4 12.6OL-29 51.6 *** 17 100.0 58.7 16.5OL-30 38.8 *** 11 100.0 58.5 10.8OL-31 53.2 *** 5 100.0 57.9 5.2OL-32 32.9 *** 8 100.0 59.3 7.6OL-33 25.8 *** 44 100.0 45.2 43.7OL-34 37.2 *** 17 100.0 38.1 16.8*This subwatershed remains landlocked in this case. ***Runoff from this watershed drains outside of the City of Lakeville.PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-57

LOCATIONDESIGNATIONTable 4.3.3 Orchard Lake District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)OL-22 41.4 0.5 0.19 30 0.5 0.30 50 0.5 0.45 71 0.5 0.55 81 0.5 0.76 101OL-22-1 41.4 12 3 2 day 6 2 day 9 2 day 11 2 day 16OL-21 55.2 0.5 0.04 6 2 day 0.81 10 2 day 1.49 18 6 0.69 23 1 0.38 39OL-21-1 96.5 2 day 1 6 1 24 2 2 day 3 2 day 4OL-20 61.2 1 0.12 13 1 0.25 21 6 1.07 37 6 1.32 48 1 0.86 76OL-20-1 157.7 1 9 6 18 6 34 6 43 6 64OL-19 21.6 0.5 0.11 12 0.5 0.19 19 0.5 0.32 27 0.5 0.40 30 0.5 0.59 36OL-19-1 179.3 2 day 7 2 day 15 2 day 29 2 day 38 6 57OL-23 46.7 0.5 0.12 9 1 0.25 14 1 0.42 24 1 0.53 30 1 0.78 45OL-23-1 226.0 2 day 7 2 day 23 2 day 44 2 day 58 6 85OL-18A 7.5 0.5 0.15 5 0.5 0.20 7 0.5 0.30 9 0.5 0.36 10 0.5 0.51 13OL-18-1 7.5 3 1 0.5 1 6 2 3 2OL-18B 7.1 0.5 0.15 4 0.5 0.21 5 0.5 0.33 7 0.5 0.40 9 0.5 0.57 13OL-18-2 7.1 2 day 1 1 1 6 2 3 2 6 3OL-18D 3.3 0.5 0.14 3 0.5 0.20 4 0.5 0.29 5 0.5 0.35 5 0.5 0.50 6OL-18-4 17.9 0.5 1 3 2 12 4 2 day 5 6 6OL-18C 11.6 0.5 0.09 3 0.5 0.17 5 1 0.50 9 1 0.64 13 1 0.94 22OL-18-3 29.5 2 day 3 6 5 6 9 3 10 6 13OL-17A 58.2 0.5 0.14 44 0.5 0.25 67 0.5 0.42 90 0.5 0.52 102 1 1.16 135OL-17-1 313.7 0.5 14 2 day 37 2 day 73 2 day 91 2 day 125OL-17B2 23.2 0.5 0.52 45 0.5 0.78 74 0.5 1.07 107 0.5 1.23 122 0.5 1.56 152OL-17-4 23.2 2 day 2 3 2 6 3 24 4 2 day 5OL-17B1 19.3 0.5 0.33 24 0.5 0.50 39 0.5 0.71 57 0.5 0.83 66 0.5 1.09 81OL-17-2 42.5 0.5 17 0.5 27 0.5 38 0.5 44 0.5 58400 356.2 0.5 31 0.5 48 2 day 83 2 day 103 2 day 143OL-16A 27.7 0.5 0.13 13 0.5 0.19 18 0.5 0.27 24 0.5 0.33 27 1 0.74 39OL-16-2 383.9 1 34 0.5 50 2 day 75 2 day 92 2 day 157OL-16B 34.0 0.5 0.26 27 0.5 0.39 44 0.5 0.55 64 0.5 0.65 74 0.5 0.87 95OL-16-1 417.9 1 51 1 75 1 91 2 day 101 2 day 181OL-7 75.3 6 0.32 13 1 0.28 31 1 0.52 61 1 0.67 79 1 0.99 119OL-7-1 75.3 6 13 6 31 1 56 1 72 1 108OL-6 90.9 6 0.66 31 6 1.25 58 1 0.96 93 1 1.17 113 1 1.61 157OL-6-1 166.2 6 37 6 72 6 79 6 118 6 190OL-5 27.7 6 0.20 4 6 0.56 10 6 1.03 18 1 0.51 23 1 0.81 37OL-5-1 27.7 12 2 3 3 2 day 4 12 4 3 4OL-4A 68.9 1 0.42 55 1 0.81 108 1 1.25 170 1 1.49 204 1 1.99 274OL-4 61.5 2 day 0.27 3 2 day 0.76 9 2 day 1.43 17 6 0.65 21 6 1.05 33OL-4-1 324.3 6 57 6 117 6 159 6 182 6 292OL-3 76.8 0.5 0.16 46 0.5 0.29 71 0.5 0.48 121 0.5 0.59 153 0.5 0.83 225RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-58

LOCATIONDESIGNATIONTable 4.3.3 Orchard Lake District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)OL-3-1 401.1 2 day 33 2 day 53 2 day 66 2 day 71 2 day 81OL-2 105.5 2 day 0.45 9 2 day 1.06 21 6 0.71 36 6 0.92 47 6 1.39 71OL-2-1 506.6 10 day 31 2 day 49 2 day 63 2 day 69 2 day 93OL-15 63.4 0.5 0.10 26 0.5 0.18 42 0.5 0.31 61 0.5 0.40 70 1 0.95 93OL-15-1 63.4 0.5 15 0.5 27 6 42 6 53 1 87OL-14 36.5 1 0.32 11 1 0.51 17 1 0.77 26 1 0.92 32 1 1.25 43OL-14-1 36.5 3 3 2 day 8 6 17 6 21 6 31OL-13 122.6 2 day 0.66 15 6 0.55 32 6 0.97 58 6 1.22 73 6 1.77 106OL-13-1 222.6 2 day 24 2 day 48 6 85 6 108 6 157OL-12B 22.6 1 0.39 16 1 0.61 26 0.5 0.64 37 0.5 0.74 43 0.5 0.98 58OL-12-2 22.6 3 1 2 day 2 6 2 2 day 3 2 day 4OL-12A 56.6 0.5 0.37 81 0.5 0.57 133 0.5 0.80 189 0.5 0.93 216 0.5 1.21 269OL-12-1 301.8 1 36 2 day 62 6 100 6 120 6 162OL-11 61.0 6 0.57 16 6 1.11 32 6 1.75 50 6 2.10 59 3 2.23 79OL-11-1 362.8 2 day 36 2 day 68 2 day 94 12 107 12 131OL-10 32.3 0.5 0.19 24 0.5 0.31 40 0.5 0.48 57 0.5 0.58 66 0.5 0.80 81OL-10-1 32.3 6 2 2 day 5 2 day 8 2 day 9 2 day 13OL-9 154.1 2 day 0.51 14 2 day 1.18 31 6 0.80 54 6 1.02 69 6 1.53 102OL-9-1 549.2 4 day 9 2 day 55 2 day 129 2 day 158 2 day 203OL-8 61.3 2 day 0.62 8 6 0.51 17 6 0.93 32 6 1.17 41 1 0.73 63OL-8-1 61.3 0.5 6 0.5 6 3 7 2 day 8 6 8OL-24 47.0 2 day 0.71 6 6 0.59 14 6 1.06 27 6 1.32 35 6 1.90 51OL-24-1 47.0 10 day 0 10 day 1 10 day 5 2 day 5 2 day 17OL-26 32.7 0.5 0.43 29 0.5 0.61 41 0.5 0.81 54 0.5 0.92 62 1 1.58 79OL-26-1 32.7 ** ** ** ** ** ** 30 days 0 ** **OL-1 424.8 1 0.72 665 0.5 0.83 1102 0.5 1.15 1628 0.5 1.32 1893 0.5 1.68 2508OL-1-1 1443.3 10 day 26 10 day 38 4 day 52 4 day 64 4 day 86**This pond remains landlocked for this case. The critical event is the 30-day snowmelt, shown for the 100-year frequency event. Otherfrequency events were not determined for landlocked basins.RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-59

PONDNAMENWL(MSL)PEAKELEV.(FT)Table 4.3.4 Orchard Lake District: Existing Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)OL-1-1 976.7 977.4 181.8 26 977.8 275.4 38 978.2 379.7 53 978.4 448.7 65 978.9 589.4 87OL-2-1 976.7 977.4 3.8 31 978.2 11.9 49 978.9 20.9 63 979.2 25.2 69 979.6 30.1 93OL-3-1 980.4 984.1 14.9 33 985.8 28.4 53 987.2 45.4 66 987.9 55.1 71 989.1 75.7 81OL-4-1 987.5 989.5 2.6 57 990.0 3.9 117 990.2 4.6 159 990.2 4.9 182 990.5 6.6 292OL-5-1 988.8 989.7 0.5 2 990.7 1.3 3 992.0 2.6 4 992.3 3.4 4 993.0 5.1 4OL-6-1 998.0 1000.5 1.8 37 1002.1 3.4 72 1003.7 8.0 79 1004.2 9.7 118 1004.5 11.1 190OL-7-1 1022.0 1022.0 0.0 13 1022.2 0.2 31 1022.4 0.4 56 1022.5 0.6 72 1022.8 0.9 108OL-8-1 977.9 978.5 0.1 6 978.9 1.6 6 979.7 4.1 7 980.0 5.6 8 980.4 9.2 8OL-9-1 985.0 992.6 48.0 9 992.9 53.5 55 993.1 56.8 129 993.2 57.8 158 993.2 59.1 203OL-10-1 997.2 997.8 1.3 2 998.2 2.3 5 998.7 3.3 8 998.9 3.8 9 999.4 4.9 13OL-11-1 1021.9 1024.5 4.9 36 1025.9 9.4 68 1027.5 16.2 94 1028.4 20.3 107 1030.2 30.6 131OL-12-1 1024.6 1026.9 0.9 36 1028.1 1.7 62 1029.6 3.3 100 1030.5 4.6 120 1032.8 8.1 162OL-12-2 1040.4 1040.7 1.5 1 1041.0 2.5 2 1041.3 3.8 2 1041.4 4.4 3 1041.7 5.8 4OL-13-1 1046.2 1046.6 1.2 24 1047.0 2.4 48 1047.2 4.2 85 1047.4 5.3 108 1047.7 7.7 157OL-14-1 1099.7 1099.9 1.1 3 1100.0 1.9 8 1100.1 2.3 17 1100.1 2.5 21 1100.2 2.9 31OL-15-1 1061.5 1062.0 0.2 15 1062.1 0.2 27 1062.2 0.4 42 1062.2 0.4 53 1062.4 0.6 87OL-16-1 990.3 993.7 0.4 51 995.0 0.5 75 995.8 0.6 91 996.4 0.7 101 998.1 0.9 181OL-16-2 995.5 998.7 0.4 34 1000.1 0.5 50 1003.4 3.6 75 1004.8 6.1 92 1005.3 7.3 157OL-17-1 1012.1 1013.2 0.4 14 1014.5 0.9 37 1015.7 1.8 73 1016.5 2.3 91 1018.0 3.0 125OL-17-2 1008.2 1010.0 0.1 17 1010.5 0.2 27 1011.0 0.3 38 1011.2 0.3 44 1011.8 0.4 58OL-17-4 1028.0 1028.7 2.3 2 1029.1 3.6 2 1029.5 5.0 3 1029.8 5.7 4 1030.2 7.2 5OL-18-1 1050.0 1050.2 0.2 0 1050.4 0.3 1 1050.6 0.5 1 1050.7 0.6 2 1050.9 0.8 2OL-18-2 1056.9 1057.1 0.1 1 1057.4 0.3 1 1057.6 0.4 2 1057.8 0.5 2 1058.0 0.7 3OL-18-3 1042.0 1042.5 0.1 3 1043.1 0.2 5 1043.8 0.3 9 1044.1 0.3 10 1044.9 0.6 13OL-18-4 1047.9 1048.0 0.1 1 1048.1 0.1 2 1048.3 0.2 4 1048.4 0.2 5 1048.5 0.3 6OL-19-1 1044.0 1044.2 12.0 7 1044.4 13.5 15 1044.6 14.9 29 1044.6 15.3 38 1044.8 16.3 57OL-20-1 1057.5 1057.6 0.1 9 1057.7 0.3 18 1057.8 0.6 34 1057.9 0.7 43 1058.0 1.1 64OL-21-1 1082.6 1082.9 4.0 1 1083.1 8.3 1 1083.5 13.8 2 1083.7 16.9 3 1084.0 23.6 4OL-22-1 1094.5 1095.0 1.3 3 1095.5 2.5 6 1096.0 3.9 9 1096.2 4.5 11 1096.7 5.8 16OL-23-1 1039.0 1041.4 5.4 7 1041.7 6.2 23 1041.8 6.6 44 1041.9 6.8 58 1042.0 7.2 85OL-24-1 980.0 985.8 9.1 0 985.8 9.3 1 986.0 9.9 5 986.0 9.9 5 986.2 10.7 17OL-25-1 978.5 ** ** 0 ** ** 0 ** ** 0 980.8 165.5 0 ** ** 0OL-26-1 997.0 ** ** 0 ** ** 0 ** ** 0 1001.1 17.6 5 ** ** 0OL-27-1 933.4 ** ** 0 ** ** 0 ** ** 0 945.9 56.0 0 ** ** 0STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)OL-28-1130.0 5OL-28-2 983.8 ** ** 0 ** ** 0 ** ** 0 1000.8 25.9 0 ** ** 0OL-29-1 1038.0 ** ** 0 ** ** 0 ** ** 0 1044.4 38.7 0 ** ** 0**This pond remains landlocked for this case. The critical event is the 30-day snowmelt, which is shown for the 100-year frequency event.1 Information for this pond was obtained from the City of Burnsville Drainage Plan.PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-60

SUBWATERSHEDNAMEAREA(AC)Table 4.3.5 Orchard Lake District: Proposed Conditions – Hydrologic and Hydraulic ParametersHYDRAULICLENGTH(FT)METHODUSEDLAGTIMEDISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBEROL-1A 385.2 1000 Kin 200 74 29.8 66.4 0.0 70.2 98.0 0.0OL-1B 39.6 800 Kin 50 35 69.8 75.2 0.0 30.2 98.0 0.0OL-2 105.5 1200 Kin 60 28 80.5 58.2 0.0 19.5 98.0 0.0OL-3 76.8 SCS 0.10 300 13 100.0 67.0 13.0OL-4A 61.5 1200 Kin 200 26 81.9 59.1 0.0 18.1 98.0 0.0OL-4B 68.9 SCS 0.20 1700 5 100.0 82.5 5.0OL-5 27.7 SCS 0.30 300 1 100.0 65.5 1.0OL-6 90.9 SCS 0.60 1600 11 100.0 79.0 11.0OL-7 75.3 SCS 0.30 1000 19 100.0 70.5 19.0OL-8 61.3 1200 Kin 100 32 77.0 59.2 0.0 23.0 98.0 0.0OL-9 154.1 5200 Kin 300 66 40.4 64.5 0.0 59.6 98.0 0.0OL-10 32.3 1100 Kin 3080 34 74.0 63.0 0.0 26.0 98.0 0.0OL-11 61.0 2200 Kin 4200 57 49.1 64.1 0.0 50.9 98.0 0.0OL-12A 56.6 2400 Kin 200 77 32.3 65.9 0.0 67.7 98.0 0.0OL-12B 22.6 700 Kin 1100 68 40.0 64.3 0.0 60.0 98.0 0.0OL-13 122.6 2000 Kin 1400 52 57.0 64.3 0.0 43.0 98.0 0.0OL-14 36.5 1400 Kin 1400 41 66.7 63.9 0.0 33.3 98.0 0.0OL-15 63.4 1500 Kin 400 31 76.9 63.8 0.0 23.1 98.0 0.0OL-16A 27.7 1200 Kin 500 67 39.6 61.5 0.0 60.4 98.0 0.0OL-16B 34.0 1900 Kin 500 78 30.1 62.6 0.0 69.9 98.0 0.0OL-17A1 46.6 1600 Kin 1700 77 31.5 68.5 0.0 68.5 98.0 0.0OL-17A2 11.6 700 Kin 900 80 28.0 67.5 0.0 72.0 98.0 0.0OL-17B1 19.3 1500 Kin 600 65 41.4 63.6 0.0 58.6 98.0 0.0OL-17B2 23.2 1500 Kin 600 82 24.6 68.9 0.0 75.4 98.0 0.0OL-18A 7.5 500 Kin 50 37 71.1 61.5 0.0 28.9 98.0 0.0OL-18B 7.1 500 Kin 250 35 73.4 63.0 0.0 26.6 98.0 0.0OL-18C 11.6 450 Kin 1700 33 73.9 63.5 0.0 26.1 98.0 0.0OL-18D 3.3 SCS 0.02 400 44 100.0 61.0 43.5OL-19 21.6 600 Kin 1700 34 74.3 63.0 0.0 25.7 98.0 0.0OL-20 61.2 1200 Kin 400 37 73.9 63.5 0.0 26.1 98.0 0.0OL-21 55.2 700 Kin 1300 48 58.2 63.2 0.0 41.8 98.0 0.0OL-22 41.4 1400 Kin 630 35 72.9 61.5 0.0 27.1 98.0 0.0OL-23 46.7 1900 Kin 1700 41 67.8 63.2 0.0 32.2 98.0 0.0OL-24 47.0 1400 Kin 100 80 28.0 68.0 0.0 72.0 98.0 0.0OL-25 220.6 1800 Kin 100 58 48.6 66.0 0.0 51.4 98.0 0.0OL-26 32.7 1100 Kin 600 43 64.1 62.1 0.0 35.9 98.0 0.0OL-27 74.6 * 32 76.6 63.0 0.0 23.4 98.0 0.0OL-28 113.3 *** 37 71.7 63.1 0.0 28.3 98.0 0.0OL-29 51.6 *** 36 72.4 63.0 0.0 27.6 98.0 0.0OL-30 38.8 *** 33 75.7 63.0 0.0 24.3 98.0 0.0PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-61

SUBWATERSHEDNAMEAREA(AC)Table 4.3.5 Orchard Lake District: Proposed Conditions – Hydrologic and Hydraulic ParametersHYDRAULICLENGTH(FT)METHODUSEDLAGTIMEDISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBEROL-31 53.2 *** 30 79.0 62.6 0.0 21.0 98.0 0.0OL-32 32.9 *** 31 77.6 63.7 0.0 22.4 98.0 0.0OL-33 25.8 *** 55 50.6 53.4 0.0 49.4 98.0 0.0OL-34 37.2 *** 30 79.0 50.5 0.0 21.0 98.0 0.0*This subwatershed remains landlocked in this case.***Runoff from this subwatershed drains outside of the City of Lakeville.PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-62

LOCATIONDESIGNATIONTOTALDRAINAGEAREA(AC)Table 4.3.6 Orchard Lake District: Proposed Conditions – Critical Events and Corresponding RunoffCRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)OL-22 41.4 0.5 0.27 43 0.5 0.42 70 0.5 0.61 101 0.5 0.72 114 0.5 0.96 145OL22-1 41.4 2 day 4 6 6 2 day 10 12 12 12 17OL-21 55.2 0.5 0.41 105 0.5 0.63 166 0.5 0.89 227 0.5 1.03 268 0.5 1.33 335OL-21-1 96.5 2 day 2 2 day 3 2 day 4 24 4 2 day 5OL-20 61.2 1 0.35 36 1 0.59 60 1 0.89 90 1 1.06 106 0.5 0.99 146OL-20-1 157.5 2 day 3 24 4 2 day 6 2 day 6 24 7OL-19 21.6 0.5 0.25 27 0.5 0.40 43 0.5 0.60 61 0.5 0.72 68 0.5 0.97 85OL-19-1 179.3 2 day 4 2 day 7 2 day 10 2 day 11 2 day 13OL-23 46.7 0.5 0.32 46 0.5 0.50 76 0.5 0.72 109 0.5 0.85 129 0.5 1.12 168OL-23-1 46.7 6 4 6 6 6 8 6 9 6 10401 226.0 2 day 8 2 day 13 2 day 19 2 day 20 2 day 23OL-18A 7.5 0.5 0.28 12 0.5 0.44 19 0.5 0.64 25 0.5 0.75 29 0.5 34OL-18-1 7.5 1 1 0.5 1 3 2 1 2 3 3OL-18B 7.1 0.5 0.26 11 0.5 0.42 16 0.5 0.62 22 0.5 0.73 25 0.5 0.99 30OL-18-2 7.1 0.5 1 6 2 1 2 6 3 6 6OL-18D 3.3 0.5 0.52 10 0.5 0.74 14 0.5 1.00 18 0.5 1.14 19 0.5 1.43 24OL-18-4 17.9 0.5 2 6 4 6 6 6 7 6 10OL-18C 11.6 1 0.35 9 0.5 0.41 14 0.5 0.62 22 0.5 0.73 26 0.5 0.99 36OL-18-3 29.5 3 3 6 5 12 8 6 9 6 11402 255.5 2 day 11 2 day 19 2 day 26 2 day 29 2 day 34OL-17A2 11.6 0.5 0.71 44 0.5 1.08 67 0.5 1.46 92 0.5 1.66 104 0.5 2.06 130OL-17-3 11.6 0.5 15 0.5 26 0.5 59 0.5 74 0.5 103OL-17A1 46.6 0.5 0.68 185 0.5 1.03 277 0.5 1.41 375 0.5 1.60 427 0.5 2.00 521OL-17-1 313.7 1 46 1 73 1 100 1 114 1 137OL-17B2 23.2 0.5 0.75 66 0.5 1.13 106 0.5 1.52 153 0.5 1.73 176 0.5 2.15 217OL-17-4 23.2 6 2 6 3 6 4 6 4 6 5OL-17B1 19.3 0.5 0.58 42 0.5 0.87 69 0.5 1.20 99 0.5 1.37 113 0.5 1.72 140OL-17-2 42.5 0.5 31 0.5 48 0.5 74 0.5 85 0.5 107400 356.2 1 69 0.5 109 0.5 153 0.5 174 0.5 216OL-16A 27.7 0.5 0.60 72 0.5 0.89 114 0.5 1.21 164 0.5 1.38 184 0.5 1.73 231OL-16-2 383.9 1 65 1 100 1 140 1 160 1 198OL-16B 34.0 0.5 0.69 78 0.5 1.03 130 0.5 1.39 187 0.5 1.58 218 0.5 1.96 279OL-16-1 417.9 1 99 0.5 153 0.5 216 0.5 247 0.5 312OL-7 75.3 1 0.36 39 1 0.64 72 1 0.98 113 1 1.17 136 1 1.5 187OL-7-1 75.3 6 11 6 18 6 26 6 29 6 33OL-6 90.9 1 0.40 37 1 0.75 72 1 1.16 112 1 1.39 134 1 1.86 180OL-6-1 166.2 6 40 6 71 6 76 6 80 6 140OL-5 27.7 6 0.23 4 6 0.61 10 1 0.42 19 1 0.55 25 1 0.86 39OL-5-1 27.7 12 2 3 3 2 day 4 12 4 3 4OL-4B 68.9 1 0.42 55 1 0.81 108 1 1.25 170 1 1.49 204 1 1.9 274CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-63

LOCATIONDESIGNATIONTOTALDRAINAGEAREA(AC)Table 4.3.6 Orchard Lake District: Proposed Conditions – Critical Events and Corresponding RunoffCRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)OL-4A 61.5 0.5 0.18 56 0.5 0.27 88 0.5 0.41 120 0.5 0.50 135 0.5 0.70 169OL-4-1 324.3 6 65 6 121 6 170 6 196 1 251OL-3 76.8 0.5 0.16 46 0.5 0.29 71 0.5 0.48 121 0.5 0.59 153 0.5 0.83 225OL-3-1 401.1 2 day 36 2 day 57 2 day 68 2 day 72 2 day 81OL-2 105.5 0.5 0.19 108 0.5 0.29 171 0.5 0.43 228 0.5 0.52 256 0.5 0.71 321OL-2-1 506.6 10 day 25 2 day 44 2 day 71 2 day 82 2 day 102OL-15 63.4 0.5 0.23 58 0.5 0.37 95 0.5 0.57 136 0.5 0.68 155 0.5 0.93 201OL-15-1 63.4 1 4 2 day 7 6 8 2 day 11 2 day 20OL-14 36.5 0.5 0.33 46 0.5 0.52 75 0.5 0.75 107 0.5 0.88 124 0.5 1.16 153OL-14-1 36.5 1 1 6 2 12 3 2 day 4 2 day 5OL-13 122.6 1 0.57 119 1 0.89 196 1 1.26 283 1 1.46 328 0.5 1.38 435OL-13-1 222.6 6 26 6 42 6 60 6 67 6 77OL-12B 22.6 1 0.78 31 1 1.18 52 1 1.62 74 0.5 1.40 86 0.5 1.76 114OL-12-2 22.6 2 day 2 6 2 6 3 2 day 4 2 day 5OL-12A 56.6 0.5 0.67 148 0.5 1.01 241 0.5 1.37 347 0.5 1.56 394 0.5 1.95 492OL-12-1 301.8 1 62 1 86 1 111 1 120 1 141OL-11 61.0 0.5 0.50 132 0.5 0.77 210 0.5 1.06 299 0.5 1.22 336 0.5 1.55 434OL-11-1 362.8 6 50 6 74 6 93 6 103 12 119OL-10 32.3 0.5 0.26 33 0.5 0.41 53 0.5 0.61 76 0.5 0.72 88 0.5 0.97 109OL-10-1 32.3 3 2 12 5 12 8 2 day 10 12 13OL-9 154.1 0.5 0.59 279 0.5 0.89 459 0.5 1.22 652 0.5 1.39 761 0.5 1.75 979OL-9-1 549.2 6 69 12 98 12 117 12 128 12 151OL-8 61.3 0.5 0.23 63 0.5 0.35 103 0.5 0.51 145 0.5 0.60 168 0.5 0.82 209OL-8-1 61.3 0.5 6 3 7 0.5 7 6 8 3 8OL-24 47.0 0.5 0.71 111 0.5 1.08 186 0.5 1.46 265 0.5 1.66 311 0.5 2.07 398OL-24-1 47.0 1 22 1 28 1 30 1 31 3 34OL-25 220.6 0.5 0.48 523 0.5 0.75 869 0.5 1.05 1212 0.5 1.21 1359 0.5 1.56 1683OL-25-1 220.6 3 1 24 2 2 day 2 2 day 3 2 day 3OL-26 32.7 0.5 0.35 54 0.5 0.54 85 0.5 0.77 120 0.5 0.90 132 0.5 1.18 69OL-26-1 32.7 6 2 6 3 24 5 2 day 6 2 day 8OL-1B 39.6 1 0.51 35 0.5 0.61 62 0.5 0.91 98 0.5 1.08 116 0.5 1.42 165OL-1-2 260.2 6 1 2 day 2 4 day 3 2 day 3 4 day 4OL-1A 385.2 1 0.91 768 0.5 1.05 1282 0.5 1.42 1873 0.5 1.61 2175 0.5 2.01 2856OL-1-1 2260.0 4 day 33 4 day 51 4 day 74 4 day 86 4 day 137CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-64

PONDNAMENWL(MSL)PEAKELEV.(FT)Table 4.3.7 Orchard Lake District: Proposed Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)OL-1-1 976.7 977.6 236.4 33 978.1 365.9 51 978.6 506.6 74 978.9 581.2 86 979.4 706.8 137STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)OL-1-2 978.5 979.0 7.9 1 979.2 12.6 2 979.5 17.7 3 979.6 20.2 3 979.9 25.5 4OL-2-1 976.7 978.6 16.4 25 979.7 31.1 44 980.1 36.7 71 980.1 37.9 82 980.4 41.3 102OL-3-1 980.4 984.4 17.1 36 986.1 31.0 57 987.5 48.5 68 988.1 58.1 72 989.2 78.8 81OL-4-1 987.5 989.6 2.8 65 990.1 4.0 121 990.2 4.8 170 990.2 5.1 196 990.4 6.0 251OL-5-1 988.8 989.8 0.6 2 990.7 1.4 3 992.0 2.7 4 992.3 3.5 4 993.0 5.2 4OL-6-1 998.0 1000.7 1.9 40 1002.0 3.2 71 1003.1 6.4 76 1003.9 8.6 80 1004.3 10.1 140OL-7-1 1022.0 1023.6 2.5 11 1024.6 4.7 18 1025.5 7.4 26 1026.1 8.8 29 1026.9 12.1 33OL-8-1 977.9 978.8 1.0 6 979.2 2.4 7 980.0 5.2 7 980.2 7.0 8 980.5 10.7 8OL-9-1 985.0 989.0 12.1 69 990.2 20.3 98 991.2 30.9 117 991.8 36.8 128 992.6 48.1 151OL-10-1 997.2 997.9 1.5 2 998.3 2.5 5 998.8 3.5 8 999.0 4.1 10 999.5 5.1 13OL-11-1 1021.9 1025.1 6.9 50 1026.2 10.7 74 1027.4 15.9 93 1028.1 18.8 103 1029.2 24.9 119OL-12-1 1024.6 1028.1 1.7 62 1029.0 2.7 86 1030.0 3.9 111 1030.5 4.5 120 1031.5 6.1 141OL-12-2 1040.4 1041.0 2.6 2 1041.3 3.9 2 1041.6 5.3 3 1041.8 6.1 4 1042.1 7.6 5OL-13-1 1044.0 1044.9 5.3 26 1045.3 8.7 42 1045.9 12.6 60 1046.1 14.7 67 1046.8 19.8 77OL-14-1 1098.9 1099.5 3.3 1 1099.8 5.3 2 1100.2 7.7 3 1100.4 8.9 4 1100.8 11.5 5OL-15-1 1061.5 1063.5 2.5 4 1064.6 5.1 7 1065.6 8.3 8 1066.1 10.0 11 1066.7 12.4 20OL-16-1 990.3 993.4 0.3 99 994.6 0.5 153 996.0 0.6 216 996.6 0.7 247 997.8 0.8 312OL-16-2 995.5 998.1 2.1 65 999.6 3.2 100 1000.7 4.4 140 1001.3 5.0 160 1002.3 6.2 198OL-17-1 1012.1 1014.8 2.4 46 1015.7 3.3 73 1016.9 4.6 100 1017.5 5.3 114 1018.7 6.7 137OL-17-2 1008.2 1010.6 0.2 31 1011.4 0.3 48 1012.1 0.4 74 1012.3 0.5 85 1012.6 0.6 107OL-17-3 1031.9 1037.3 0.3 15 1038.4 0.5 26 1038.7 0.5 59 1038.7 0.5 74 1038.9 0.6 103OL-17-4 1028.0 1029.0 3.1 2 1029.4 4.6 3 1029.9 6.1 4 1030.1 6.9 4 1030.5 8.6 5OL-18-1 1050.0 1050.3 0.3 1 1050.5 0.5 1 1050.8 0.7 2 1050.9 0.8 2 1051.2 1.1 3OL-18-2 1056.9 1057.3 0.2 1 1057.5 0.4 2 1057.9 0.6 2 1058.0 0.7 3 1058.2 0.8 6OL-18-3 1042.0 1042.6 0.6 3 1043.1 1.1 5 1043.6 1.6 8 1043.8 1.8 9 1044.3 2.6 11OL-18-4 1047.9 1048.1 0.1 2 1048.3 0.2 4 1048.5 0.3 6 1048.5 0.4 7 1048.9 0.6 10OL-19-1 1040.0 1040.8 1.0 4 1041.3 1.7 7 1041.9 2.5 10 1042.1 2.9 11 1042.4 3.9 13OL-20-1 1058.6 1059.9 5.6 3 1060.6 9.7 4 1061.4 14.6 6 1061.9 17.2 6 1062.7 22.8 7OL-21-1 1082.6 1083.2 10.0 2 1083.6 16.5 3 1084.0 23.6 4 1084.2 27.6 4 1084.7 36.1 5OL-22-1 1094.5 1095.1 1.6 4 1095.6 2.9 6 1096.1 4.2 10 1096.3 4.9 12 1096.8 6.2 17OL-23-1 1039.0 1040.3 2.4 4 1041.0 4.1 6 1041.7 6.1 8 1042.0 7.3 9 1042.7 10.0 10OL-24-1 980.0 983.1 2.2 22 984.0 3.5 28 984.6 5.2 30 984.9 6.2 31 985.5 8.3 34OL-25-1 981.2 981.7 43.9 1 982.0 63.4 2 982.2 84.6 2 982.4 97.3 3 982.7 122.0 3OL-26-1 997.0 997.6 2.3 2 998.0 3.9 3 998.4 5.4 5 998.6 6.3 6 999.0 8.0 8OL-27-1 933.4 ** ** 0 ** ** 0 ** ** 0 945.9 56.0 0 ** ** 0OL-28-1130.0 5OL-28-2 983.8 ** ** 0 ** ** 0 ** ** 0 1000.8 25.9 0 ** ** 0OL-29-1 1038.0 ** ** 0 ** ** 0 ** ** 0 1044.4 38.7 0 ** ** 0**This pond remains landlocked for this case. The critical event is the 30-day snowmelt, which is shown for the 100-year frequency event.1 Information for this pond was obtained from the City of Burnsville Drainage Plan.PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-65

CONDITIONTable 4.4.1 Lake Marion PONDNET ResultsAVERAGESURFACEINFLOWVOLUME(acre-feet)ESTIMATEDPHOSPHORUSLOAD(Pounds/Year)AVERAGEPHOSPHORUSCONCENTRATION(ppb)PERCENT TOTALPHOSPHORUSREMOVALExisting 1,200 700 59 68Future Conditions with3,730 1,600 56 55Existing WetlandsProposed 3,700 1,600 56 55Lakeville Water Resources Management Plan Page 4-66

SUBWATERSHEDNAMETable 4.4.2 Lake Marion District: Existing Conditions – Hydrologic and Hydraulic ParametersAREA(ac)HYDRAULICLENGTH(ft)METHODUSEDLAG TIME(hr)DIST. TO D.S.WATERSHED(ft)COMPOSITEPERCENTIMPERV.% OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBER%IMPERV.% OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERML-1 1107.2 SCS 0.19 51 100.0 55.0 51.0ML-2 60.6 SCS 0.39 100 6 100.0 68.0 5.5ML-3 61.8 SCS 0.19 200 5 100.0 68.0 5.0ML-4 31.4 SCS 0.22 1900 4 100.0 77.0 3.8ML-5 100.5 SCS 0.56 600 1 100.0 76.0 0.6ML-6 108.2 SCS 0.19 1600 20 100.0 68.0 20.1ML-7 84.5 SCS 0.21 1200 10 100.0 77.0 10.1ML-8 67.2 SCS 0.23 1400 2 100.0 63.1 2.4ML-9 66.6 SCS 0.67 1400 2 100.0 63.2 2.3ML-10 73.0 SCS 0.90 400 1 100.0 61.0 1.1ML-11 39.0 SCS 0.26 0 5 100.0 79.0 5.2ML-12 183.6 SCS 1.30 4000 5 100.0 64.0 4.7ML-13 46.7 SCS 0.20 100 15 100.0 50.5 14.9ML-14 42.0 SCS 0.34 300 3 100.0 51.2 3.3ML-15 46.2 SCS 0.26 1100 5 100.0 56.2 4.9ML-17 104.1 SCS 0.24 800 16 100.0 51.0 16.3ML-18 59.2 SCS 0.28 800 2 100.0 61.0 2.0ML-19 63.8 SCS 0.36 100 14 100.0 59.2 14.4ML-20 89.0 SCS 1.00 1400 2 100.0 66.0 1.5ML-21 91.5 SCS 0.39 1800 2 100.0 72.0 1.6ML-22 184.3 SCS 0.67 1900 5 100.0 75.3 4.7ML-23 158.1 SCS 0.93 1600 5 100.0 72.0 5.2ML-24A 74.9 SCS 1.30 100 6 100.0 45.0 6.4ML-24B 44.2 SCS 0.87 1700 10 100.0 51.0 10.3ML-24C 24.3 SCS 0.12 1800 12 100.0 50.0 12.0ML-25 145.9 SCS 0.90 800 1 100.0 50.0 1.0ML-26 94.1 SCS 0.80 300 4 100.0 55.0 3.5ML-27 90.2 SCS 0.38 3200 1 100.0 73.0 0.7ML-28 97.3 SCS 0.80 900 0 100.0 61.0 0.2ML-29 91.5 SCS 0.33 2100 4 100.0 68.0 4.0ML-30 23.7 SCS 0.17 500 5 100.0 64.0 5.0ML-31 76.2 SCS 0.53 100 1 100.0 60.0 0.5ML-32 44.2 SCS 0.27 1900 6 100.0 62.0 5.6ML-33 59.2 800 Kin 200 12 90.0 58.0 0.0 10.0 98.0 0.0ML-34 79.4 SCS 0.93 400 15 100.0 62.0 15.2ML-35 74.7 SCS 1.20 0 10 100.0 59.0 10.1ML-36A 29.3 SCS 0.10 2700 5 100.0 59.0 4.7ML-36B 25.5 SCS 0.15 2200 1 100.0 78.0 0.5ML-37 31.0 SCS 0.44 1000 6 100.0 63.0 5.6ML-38 45.2 SCS 0.04 400 28 100.0 63.0 27.7ML-39 35.2 SCS 0.08 400 19 100.0 59.0 19.0%IMPERV.Lakeville Water Resources Management Plan Page 4-67

Table 4.4.2 Lake Marion District: Existing Conditions – Hydrologic and Hydraulic ParametersSUBWATERSHEDNAMEAREA(ac)HYDRAULICLENGTH(ft)METHODUSEDLAG TIME(hr)DIST. TO D.S.WATERSHED(ft)COMPOSITEPERCENTIMPERV.% OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBER%IMPERV.ML-40 32.0 SCS 1.15 300 5 100.0 61.0 5.4ML-41 53.1 SCS 0.33 800 3 100.0 62.0 2.7ML-42 108.2 SCS 0.90 1900 9 100.0 64.0 8.9ML-43 43.9 SCS 0.19 800 6 100.0 59.0 6.3ML-44 129.3 SCS 0.15 100 13 100.0 60.0 13.4ML-45 95.4 SCS 0.42 1100 2 100.0 64.0 1.9ML-46 120.3 SCS 0.33 2100 10 100.0 63.0 9.6ML-47 96.3 SCS 0.35 1600 12 100.0 65.0 11.5ML-48 41.2 SCS 0.29 100 7 100.0 53.0 6.7ML-49 33.9 SCS 0.11 400 11 100.0 59.0 11.1ML-50 114.3 SCS 0.27 600 14 100.0 61.0 14.0ML-51 59.4 SCS 0.15 100 9 100.0 55.0 9.0**This pond remains landlocked for this case; critical event is the 30-day snowmelt.% OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBER%IMPERV.Lakeville Water Resources Management Plan Page 4-68

LOCATIONAREA(ac)Table 4.4.3 Lake Marion District: Existing Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(hr)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)ML-12 183.6 2 day 0.78 23 6 0.64 46 6 1.12 81 6 1.39 100 6 1.97 142ML-12-1 183.6 2 day 19 2 day 34 12 47 12 55 12 65ML-22 184.3 6 0.59 54 6 1.15 106 6 1.80 165 3 1.68 196 1 1.50 272ML-22-1 367.9 2 day 49 2 day 57 2 day 68 2 day 72 24 77ML-21 91.5 6 0.42 22 6 0.91 49 1 0.67 87 1 0.84 109 1 1.23 159ML-23 158.1 6 0.49 35 6 0.99 71 6 1.60 113 6 1.92 136 6 2.61 183ML-23-1 158.1 6 34 6 71 6 113 6 136 6 183ML-20 89.0 2 day 0.77 12 6 0.64 26 6 1.13 46 6 1.41 57 6 2.01 80ML-20-1 706.5 2 day 103 6 175 6 269 6 317 6 418ML-19 63.8 0.5 0.17 20 1 0.36 31 1 0.57 49 1 0.70 60 1 0.98 87ML-18 59.2 2 day 0.57 8 6 0.46 116 6 0.88 31 6 1.12 41 1 0.68 66ML-11 39.0 1 0.32 21 1 0.66 44 1 1.06 72 1 1.28 88 1 1.75 120ML-17 104.1 0.5 0.20 49 0.5 0.27 69 0.5 0.36 88 0.5 0.41 99 1 0.80 130ML-17-1 972.6 2 day 128 6 219 6 342 6 407 6 512ML-15 46.2 0.5 0.06 6 2 day 1.10 11 6 0.75 20 1 0.36 26 1 0.58 43ML-14 42.0 0.5 0.04 3 2 day 0.77 7 6 0.50 12 6 0.67 16 6 1.06 25ML-14-1 42.0 ** ** ** ** ** ** 30 day 0 ** **ML-13 46.7 0.5 0.18 22 0.5 0.25 31 0.5 0.33 40 0.5 0.37 45 0.5 0.50 58ML-9 66.6 2 day 0.66 9 6 0.55 19 6 1.00 34 6 1.26 43 6 1.83 62ML-8 67.2 2 day 0.67 10 6 0.55 22 1 0.37 44 1 0.50 59 1 0.78 95ML-8-1 133.8 2 day 17 6 37 6 67 6 85 6 122ML-10 73.0 2 day 0.55 8 2 day 1.26 17 6 0.85 30 6 1.09 38 6 1.62 56ML-7 84.5 1 0.34 50 1 0.66 102 1 1.05 167 1 1.27 202 1 1.72 277ML-7-1 291.3 2 day 39 6 75 6 127 6 156 6 212ML-6 108.2 0.5 0.25 73 0.5 0.42 117 1 0.93 181 1 1.10 220 1 1.49 304ML-5 100.5 6 0.54 30 6 1.11 60 1 0.83 95 1 1.03 117 1 1.45 164ML-4 31.4 1 0.26 14 1 0.56 32 1 0.94 55 1 1.14 67 1 1.58 94ML-2 60.6 6 0.38 12 6 0.82 28 1 0.60 50 1 0.76 64 1 1.11 94ML-3 61.8 6 0.37 13 1 0.32 36 1 0.59 68 1 0.75 88 1 1.09 131ML-51 59.4 0.5 0.11 20 0.5 0.15 28 0.5 0.22 37 1 0.45 45 1 0.67 73ML-51-1 59.4 10 day 0 10 day 0 10 day 33 10 day 59 10 day 64ML-49 33.9 0.5 0.13 17 0.5 0.20 23 0.5 0.31 32 0.5 0.38 39 1 0.87 61ML-49-1 33.9 0.5 9 0.5 13 1 23 1 29 1 44ML-50 114.3 0.5 0.17 43 0.5 0.26 63 1 0.60 104 1 0.73 130 1 1.04 188ML-48 41.2 0.5 0.08 7 0.5 0.11 10 1 0.26 15 1 0.34 20 1 0.53 33ML-48-1 189.4 12 3 2 day 5 2 day 41 2 day 71 2 day 115ML-47 96.3 1 0.20 26 1 0.39 50 1 0.64 87 1 0.79 108 1 1.13 157ML-46 120.3 0.5 0.12 27 1 0.32 51 1 0.54 93 1 0.68 118 1 0.99 176ML-45 95.4 2 day 0.69 14 6 0.57 31 6 1.03 56 6 1.30 71 1 0.81 105ML-45-1 312.0 2 day 36 12 48 12 57 12 118 6 283RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-69

LOCATIONAREA(ac)Table 4.4.3 Lake Marion District: Existing Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(hr)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)ML-44 129.3 0.5 0.16 66 0.5 0.24 92 0.5 0.37 133 0.5 0.45 163 1 0.98 244ML-44-1 441.3 2 day 33 2 day 49 2 day 58 2 day 66 2 day 85ML-43 43.9 0.5 0.08 9 0.5 0.12 13 1 0.36 27 1 0.47 36 1 0.73 58ML-43-1 43.9 0.5 5 6 11 1 19 6 21 6 26ML-42 108.2 6 0.36 16 6 0.75 35 6 1.24 59 6 1.52 73 6 2.12 102ML-42-1 108.2 2 day 12 6 15 12 18 12 19 12 21ML-41 53.1 2 day 0.63 7 6 0.52 16 6 0.95 30 1 0.47 38 1 0.74 60ML-41-1 205.2 2 day 21 2 day 39 6 59 6 69 6 90ML-40 32.0 2 day 0.68 4 6 0.56 7 6 0.99 13 6 1.24 16 6 1.78 24ML-40-1 32.0 6 1 2 day 3 24 4 2 day 5 2 day 7ML-39 35.2 0.5 0.23 33 0.5 0.33 47 0.5 0.47 61 0.5 0.56 70 0.5 0.76 95ML-39-1 67.2 ** ** ** ** ** ** 30 day 0 ** **ML-37 31.0 2 day 0.76 5 6 0.63 10 1 0.45 18 1 0.58 23 1 0.87 35ML-38 45.2 0.5 0.33 76 0.5 0.49 106 0.5 0.70 137 0.5 0.82 157 0.5 1.08 207ML-38-1 76.2 2 day 2 24 3 24 4 12 4 2 day 24ML-35 74.7 2 day 0.75 8 6 0.62 17 6 1.05 30 6 1.29 38 6 1.83 54ML-35-1 74.7 ** ** ** ** ** ** 30 day 0 ** **ML-36B 25.5 1 0.24 13 1 0.55 30 1 0.93 52 1 1.14 64 1 1.58 90ML-36-2 25.5 1 12 1 24 1 28 1 31 1 34ML-36A 29.3 0.5 0.06 6 0.5 0.09 9 1 0.32 19 1 0.43 26 1 0.68 43ML-36-1 29.3 0.5 6 0.5 8 1 18 1 25 1 40ML-34 79.4 1 0.24 14 6 0.85 27 6 1.34 44 6 1.62 54 6 2.21 74ML-34-1 208.9 6 19 6 40 6 79 6 97 6 129ML-33 59.2 0.5 0.10 24 0.5 0.15 39 0.5 0.25 56 0.5 0.32 65 0.5 0.48 80ML-33-1 59.2 10 day 0 10 day 10 10 day 29 10 day 56 10 day 96ML-32 44.2 0.5 0.07 7 6 0.59 15 1 0.42 29 1 0.54 38 1 0.83 60ML-32-1 103.4 10 day 0 10 day 0 10 day 17 10 day 40 10 day 91ML-31 76.2 2 day 0.49 8 2 day 1.17 18 6 0.78 33 6 1.01 43 6 1.52 64ML-31-1 179.6 2 day 7 6 13 12 20 12 37 6 140ML-30 23.7 0.5 0.06 4 1 0.24 10 1 0.46 21 1 0.60 27 1 0.90 42ML-30-1 23.7 6 2 2 day 5 3 5 1 5 0.5 5ML-29 91.5 6 0.35 18 6 0.78 42 1 0.57 78 1 0.72 100 1 1.07 150ML-28 97.3 2 day 0.52 10 2 day 1.22 23 6 0.82 40 6 1.06 52 6 1.59 76ML-27 90.2 6 0.44 23 6 0.94 50 1 0.69 90 1 0.87 114 1 1.26 165ML-26 94.1 2 day 0.41 7 2 day 0.99 17 6 0.65 29 6 0.85 38 6 1.30 59ML-25 145.9 2 day 0.19 5 2 day 0.62 18 2 day 1.24 34 2 day 1.60 43 6 0.88 63ML-25-1 330.2 2 day 30 2 day 67 6 117 6 148 6 215ML-24A 74.9 1 0.10 4 2 day 0.64 7 2 day 1.18 14 2 day 1.50 18 2 day 2.23 26ML-24-1 74.9 10 day 31 10 day 45 10 day 55 10 day 61 10 day 75ML-24B 44.2 0.5 0.12 5 1 0.22 8 6 0.75 13 6 0.93 17 6 1.35 26ML-24C 24.3 0.5 0.14 12 0.5 0.20 17 0.5 0.26 22 0.5 0.30 25 0.5 0.41 30RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-70

LOCATIONAREA(ac)Table 4.4.3 Lake Marion District: Existing Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(hr)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)ML-24-3 24.3 0.5 10 0.5 14 0.5 18 0.5 20 0.5 26ML-1 1107.2 0.5 0.61 1880 0.5 0.86 2632 0.5 1.12 3396 0.5 1.26 3800 0.5 1.55 4658ML-1-1 4982 10 day 0 10 day 0 10 day 9 10 day 16 10 day 29RUNOFF(in)**This pond remains landlocked for this case; critical event is the 30-day snowmelt.PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-71

PONDNAMENWLPEAKELEV.(ft)Table 4.4.4 Lake Marion District: Existing Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)ML-1-1 1 978.8 981.0 1507 0 981.8 1965 0 982.6 2421 9 983.0 2641 16 983.7 3093 29ML-1-1 2 978.8 982.0 983.8 984.5 985.8ML-2-1 978.8 979.7 * * 980.5 * * 981.3 * * 981.7 * * 982.5 * *ML-3-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-3-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-3-3 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-4-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-7-1 1028.0 1029.5 2.8 39 1030.9 5.4 75 1032.5 9.2 127 1033.1 11.4 156 1034.3 16.1 212ML-8-1 1054.6 1056.6 0.2 17 1058.0 0.4 37 1058.1 0.5 67 1058.1 0.5 85 1058.2 0.5 122ML-12-1 1090.9 1092.7 2.1 19 1094.5 4.5 34 1096.1 8.3 47 1097.0 10.5 55 1098.6 16.6 65ML-12-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-13-1 978.8 979.7 * * 980.5 * * 981.3 * * 981.7 * * 982.5 * *ML-14-1 997.9 998.2 1.1 0 998.6 2.9 0 999.2 5.4 0 999.5 6.9 0 1000.2 10.2 0ML-17-1 988.2 993.0 2.0 128 994.6 3.0 219 997.3 5.6 342 999.2 8.2 407 1002.5 15.3 512ML-20-1 1037.5 1040.4 7.5 103 1040.8 9.0 175 1041.1 10.7 269 1041.3 11.3 317 1041.5 12.7 418ML-22-1 1067.8 1072.0 4.2 49 1072.7 11.4 57 1073.8 23.0 68 1074.2 30.3 72 1074.8 46.8 77ML-22-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-23-1 1076.8 1077.3 0.2 34 1077.5 0.3 71 1077.6 0.3 113 1077.6 0.4 136 1077.7 0.4 183ML-24-1 985.0 985.7 2.9 31 985.8 3.1 45 985.8 3.2 55 985.8 3.2 61 985.8 3.3 75ML-24-3 1010.8 1011.9 0.1 10 1012.3 0.1 14 1012.7 0.1 18 1012.9 0.1 20 1013.5 0.2 26ML-25-1 988.1 988.6 1.0 30 988.7 1.3 67 988.9 1.7 117 989.0 2.0 148 989.3 3.1 215ML-29-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-30-1 987.9 988.9 0.4 2 989.8 0.8 5 990.5 1.5 5 990.9 1.9 5 991.8 3.1 5ML-31-1 980.4 982.1 0.1 7 983.9 1.1 13 986.8 6.4 20 988.0 9.7 37 988.2 10.3 140ML-32-1 994.7 997.5 10.6 0 998.8 16.4 0 1000.5 25.5 17 1000.8 27.1 40 1001.1 29.2 91ML-33-1 992.4 1004.4 14.5 0 1006.0 19.7 10 1006.1 20.1 29 1006.2 20.7 56 1006.4 21.3 96ML-33-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-34-1 990.2 993.3 1.1 19 995.1 2.8 40 995.5 3.4 79 995.5 3.6 97 995.6 3.7 129ML-35-1 1000.0 1000.8 5.1 0 1001.6 10.1 0 1002.6 16.3 0 1003.1 19.6 0 1004.1 26.8 0ML-36-1 1012.7 1013.2 0.0 6 1013.4 0.0 8 1014.3 0.1 18 1014.9 0.1 25 1016.1 0.1 40ML-36-2 1018.3 1020.1 0.1 12 1022.1 0.2 24 1023.3 0.6 28 1024.0 0.9 31 1024.8 1.6 34ML-37-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-38-1 997.1 998.5 5.6 2 999.6 10.1 3 1000.6 15.3 4 1001.0 18.4 4 1001.2 20.3 24ML-39-1 982.9 983.9 5.3 0 984.5 10.1 0 985.3 15.8 0 985.7 19.0 0 986.4 25.7 0ML-40-1 981.0 981.8 1.0 1 982.2 2.0 3 982.7 3.3 4 982.9 4.0 5 983.5 5.5 7ML-41-1 999.5 1001.9 0.1 21 1003.1 0.4 39 1003.2 0.4 59 1003.2 0.4 69 1003.3 0.5 90ML-42-1 1023.2 1025.8 1.6 12 1027.1 4.2 15 1028.7 8.3 18 1029.6 10.9 19 1031.4 16.7 21ML-42-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-42-3 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-42-4 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-72

PONDNAMENWLPEAKELEV.(ft)Table 4.4.4 Lake Marion District: Existing Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)ML-43-1 1010.9 1012.0 0.1 5 1012.9 0.3 11 1014.2 0.6 19 1014.8 1.0 21 1016.3 1.9 26ML-44-1 978.9 982.8 9.8 33 984.7 18.0 49 986.9 27.9 58 988.2 35.3 66 990.1 56.8 85ML-45-1 996.6 1003.5 1.8 36 1007.6 8.6 48 1011.3 20.0 57 1012.0 23.0 118 1012.3 24.1 283ML-46-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-47-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-48-1 982.1 983.6 9.4 3 984.6 19.5 5 985.1 24.4 41 985.3 25.5 71 985.4 27.1 115ML-49-1 986.6 987.4 0.2 9 987.8 0.3 13 988.4 0.4 23 988.7 0.5 29 989.5 0.8 44ML-49-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-51-1 979.6 982.1 14.3 0 983.0 20.3 0 983.2 22.2 33 983.3 22.6 59 983.3 22.7 641 Based on HEC-1 model with normal water level 978.8, which is the historical 50 percent probability level. Normal water level may change with futureincreases in watershed yields and corresponding flood levels.2 Based on frequency distribution of average annual water surface elevations 1946-1991.*This pond is considered part of Marion Lake.**This pond was not included in HEC-1 model; see development plans for additional data.PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-73

SUBWATERSHEDNAMETable 4.4.5 Lake Marion District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(ac)HYDRAULIC LENGTH(ft)METHODUSEDLAGTIME(hr)DIST. TO D.S.WATERSHEDCOMPOSITEPERCENTIMPERV.% OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBER%IMPERV.% OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERML-1 1111.7 1200 Kin 64 40.0 69.0 0.0 60.0 98.0 0.0ML-2 60.6 1600 Kin 100 31 78.0 53.0 0.0 22.0 98.0 0.0ML-3 61.8 2000 Kin 200 30 79.0 61.0 0.0 21.0 98.0 0.0ML-4 31.4 1500 Kin 1900 56 53.0 58.0 0.0 47.0 98.0 0.0ML-5 100.5 1700 Kin 600 56 53.0 64.0 0.0 47.0 98.0 0.0ML-6 108.2 2800 Kin 1600 70 37.0 65.0 0.0 63.0 98.0 0.0ML-7 84.5 1500 Kin 1200 71 36.0 63.0 0.0 64.0 98.0 0.0ML-8 67.2 1900 Kin 1500 34 74.0 69.0 0.0 26.0 98.0 0.0ML-9 66.6 2200 Kin 1400 30 79.0 64.0 0.0 21.0 98.0 0.0ML-10 73.0 1200 Kin 200 34 75.0 66.0 0.0 25.0 98.0 0.0ML-11 44.2 1000 Kin 1000 65 44.0 61.0 0.0 56.0 98.0 0.0ML-12 183.6 3200 Kin 4000 17 87.0 67.0 0.0 13.0 98.0 0.0ML-13 46.7 500 Kin 100 57 51.0 56.0 0.0 49.0 98.0 0.0ML-14 42.0 1300 Kin 600 77 70.0 48.0 0.0 30.0 98.0 0.0ML-15 46.2 1200 Kin 1100 75 32.0 57.0 0.0 68.0 98.0 0.0ML-17 92.8 1600 Kin 1000 55 53.0 60.0 0.0 47.0 98.0 0.0ML-18 65.0 2400 Kin 500 30 79.0 63.0 0.0 21.0 98.0 0.0ML-19 64.0 1700 Kin 100 48 61.0 64.0 0.0 39.0 98.0 0.0ML-20 89.0 3400 Kin 1500 30 79.0 70.0 0.0 21.0 98.0 0.0ML-21 91.5 2200 Kin 1800 23 84.0 68.0 0.0 16.0 98.0 0.0ML-22 184.3 3400 Kin 1900 24 83.0 70.0 0.0 17.0 98.0 0.0ML-23A 119.7 1900 Kin 1600 20 85.0 68.0 0.0 15.0 98.0 0.0ML-23B 38.4 1900 Kin 800 33 76.0 69.0 0.0 24.0 98.0 0.0ML-24A 74.9 1700 Kin 100 55 54.0 55.0 0.0 46.0 98.0 0.0ML-24B 39.7 2200 Kin 1700 61 46.0 58.0 0.0 54.0 98.0 0.0ML-24C 24.3 800 Kin 1800 69 38.0 58.0 0.0 62.0 98.0 0.0ML-25 145.9 2600 Kin 800 2 98.0 50.0 0.0 2.0 98.0 0.0ML-26 94.1 3200 Kin 300 19 85.0 57.0 0.0 15.0 98.0 0.0ML-27 90.2 1400 Kin 3200 24 83.0 64.0 0.0 17.0 98.0 0.0ML-28 97.3 2400 Kin 900 15 90.0 62.0 0.0 10.0 98.0 0.0ML-29 91.5 1800 Kin 2100 29 78.0 66.0 0.0 22.0 98.0 0.0ML-30 23.7 1000 Kin 500 5 95.0 64.0 0.0 5.0 98.0 0.0ML-31 76.2 1700 Kin 100 22 85.0 64.0 0.0 15.0 98.0 0.0ML-32 44.2 600 Kin 1600 20 84.0 65.0 0.0 16.0 98.0 0.0ML-33 59.2 800 Kin 300 35 73.0 62.0 0.0 27.0 98.0 0.0ML-34 71.3 2200 Kin 400 50 57.0 67.0 0.0 43.0 98.0 0.0ML-35 74.7 1500 Kin 1800 54 54.0 64.0 0.0 46.0 98.0 0.0ML-36A 29.3 1000 Kin 2700 46 63.0 63.0 0.0 37.0 98.0 0.0ML-36B 25.5 1100 Kin 2200 45 64.0 66.0 0.0 36.0 98.0 0.0ML-37 31.0 900 Kin 1000 35 74.0 68.0 0.0 26.0 98.0 0.0ML-38 53.4 500 Kin 400 47 58.0 67.0 0.0 42.0 98.0 0.0%IMPERV.Lakeville Water Resources Management Plan Page 4-74

SUBWATERSHEDNAMETable 4.4.5 Lake Marion District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(ac)HYDRAULIC LENGTH(ft)METHODUSEDLAGTIME(hr)DIST. TO D.S.WATERSHEDCOMPOSITEPERCENTIMPERV.% OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBER%IMPERV.% OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERML-39 35.2 700 Kin 200 44 63.0 63.0 0.0 37.0 98.0 0.0ML-40 32.0 1900 Kin 300 32 76.0 65.0 0.0 24.0 98.0 0.0ML-41 53.1 1600 Kin 800 30 79.0 67.0 0.0 21.0 98.0 0.0ML-42 108.2 2200 Kin 1900 39 70.0 67.0 0.0 30.0 98.0 0.0ML-43 43.9 1400 Kin 800 76 41.0 65.0 0.0 59.0 98.0 0.0ML-44 129.3 1200 Kin 100 22 85.0 62.0 0.0 15.0 98.0 0.0ML-45 95.4 1200 Kin 1100 30 79.0 68.0 0.0 21.0 98.0 0.0ML-46 120.3 1700 Kin 2100 31 78.0 66.0 0.0 22.0 98.0 0.0ML-47 96.3 1700 Kin 1600 32 79.0 67.0 0.0 21.0 98.0 0.0ML-48 57.5 900 Kin 100 26 81.0 66.0 0.0 19.0 98.0 0.0ML-49 43.1 650 Kin 400 31 74.0 62.0 0.0 26.0 98.0 0.0ML-50 88.9 1200 Kin 600 33 76.0 65.0 0.0 24.0 98.0 0.0ML-51A 41.1 1100 Kin 100 28 80.0 61.0 0.0 20.0 98.0 0.0ML-51B 18.3 900 Kin 200 30 79.0 63.0 0.0 21.0 98.0 0.0%IMPERV.Lakeville Water Resources Management Plan Page 4-75

LOCATIONAREA(ac)Table 4.4.6 Lake Marion District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(hr)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)ML-12 183.6 1 0.21 41 1 0.42 72 6 1.49 131 6 1.79 164 6 2.44 238ML-12-1 183.6 2 day 27 2 day 40 6 55 12 61 6 72ML-22 184.3 0.5 0.19 102 0.5 0.36 167 0.5 0.58 239 0.5 0.71 280 0.5 0.99 364ML-22-1 367.9 2 day 51 2 day 59 2 day 70 2 day 73 24 78ML-21 91.5 0.5 0.17 49 0.5 0.32 81 0.5 0.52 116 0.5 0.64 136 0.5 0.90 173ML-23A 119.7 1 0.24 47 0.5 0.30 75 0.5 0.50 112 0.5 0.62 131 0.5 0.88 173ML-23-1 119.7 2 day 16 2 day 24 12 31 12 33 12 37ML-23B 38.4 0.5 0.25 36 0.5 0.44 59 0.5 0.67 84 0.5 0.81 97 0.5 1.10 123ML-23-2 38.4 0.5 7 0.5 8 3 9 3 10 3 11ML-20 89.0 1 0.34 41 1 0.61 68 1 0.96 102 1 1.15 120 0.5 1.07 162ML-20-1 706.5 2 day 86 2 day 118 2 day 147 2 day 161 2 day 179ML-19 64.0 0.5 0.39 82 0.5 0.60 137 0.5 0.85 195 0.5 0.99 230 0.5 1.29 295ML-19-1 770.5 2 day 88 2 day 127 2 day 160 2 day 175 2 day 200ML-18 65.0 0.5 0.21 53 0.5 0.34 88 0.5 0.52 124 0.5 0.62 144 0.5 0.86 180ML-18-1 65.0 2 day 6 2 day 12 2 day 17 2 day 19 2 day 23ML-11 44.2 0.5 0.55 85 0.5 0.83 140 0.5 1.13 201 0.5 1.29 233 0.5 1.62 298ML-11-1 44.2 1 19 1 28 1 37 1 41 1 52ML-17 92.8 0.5 0.46 210 0.5 0.69 341 0.5 0.96 476 0.5 1.10 538 0.5 1.40 661ML-17-1 972.5 1 107 2 day 171 0.5 232 0.5 265 0.5 324ML-15 46.2 0.5 0.67 125 0.5 0.99 204 0.5 1.33 291 0.5 1.51 335 0.5 1.87 421ML-14 42.0 0.5 0.30 42 0.5 0.44 69 0.5 0.58 99 0.5 0.65 116 0.5 0.83 148ML-14-1 42.0 12 2 2 day 3 24 4 2 day 5 24 6ML-13 46.7 0.5 0.48 121 0.5 0.72 189 0.5 0.97 259 0.5 1.10 285 0.5 1.39 347ML-9 66.6 0.5 0.21 54 0.5 0.35 88 0.5 0.53 123 0.5 0.64 141 0.5 0.89 180ML-9-1 66.6 12 5 12 9 12 11 12 12 12 14ML-8 67.2 0.5 0.27 55 0.5 0.46 91 0.5 0.71 133 0.5 0.84 151 0.5 1.14 201ML-8-1 133.8 0.5 53 0.5 87 0.5 125 0.5 140 0.5 183ML-10 73.0 0.5 0.25 88 0.5 0.42 141 0.5 0.64 198 0.5 0.76 225 0.5 1.03 278ML-10-1 73.0 2 day 8 2 day 14 2 day 21 6 24 6 29ML-7 84.5 0.5 0.63 216 0.5 0.95 342 0.5 1.29 486 0.5 1.47 548 0.5 1.83 710ML-7-1 291.3 1 63 1 95 6 135 6 157 6 201ML-6 108.2 0.5 0.62 266 0.5 0.94 439 0.5 1.28 624 0.5 1.46 719 0.5 1.84 903ML-5 100.5 1 0.61 137 0.5 0.71 228 0.5 0.99 324 0.5 1.15 377 0.5 1.47 491ML-4 31.4 0.5 0.46 71 0.5 0.69 115 0.5 0.94 161 0.5 1.08 182 0.5 1.37 222ML-2 60.6 1 0.28 35 0.5 0.32 56 0.5 0.44 82 0.5 0.51 96 0.5 0.68 125ML-3 61.8 0.5 0.21 63 0.5 0.32 101 0.5 0.49 141 0.5 0.59 160 0.5 0.81 198ML-51B 18.3 0.5 0.21 15 0.5 0.34 25 0.5 0.52 34 0.5 0.62 39 0.5 0.86 50ML-51A 41.1 0.5 0.20 38 0.5 0.31 61 0.5 0.47 83 0.5 0.57 97 0.5 0.79 122ML-51A-1 59.4 24 9 24 16 24 27 24 33 24 60ML-49 43.1 0.5 0.26 56 0.5 0.40 91 0.5 0.59 127 0.5 0.70 144 0.5 0.95 179RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-76

LOCATIONAREA(ac)Table 4.4.6 Lake Marion District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(hr)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)ML-49-1 43.1 1 24 0.5 36 0.5 49 0.5 55 1 62ML-50 88.9 0.5 0.24 92 0.5 0.40 149 0.5 0.60 216 0.5 0.72 246 0.5 0.98 315ML-50-1 88.9 1 40 1 53 1 64 6 78 6 161ML-48 57.5 0.5 0.19 45 0.5 0.34 71 0.5 0.53 101 0.5 0.65 117 0.5 0.90 149ML-48-1 189.5 3 5 4 day 42 2 day 90 2 day 106 2 day 133ML-47 96.3 0.5 0.21 79 0.5 0.37 130 0.5 0.58 185 0.5 0.71 215 0.5 0.97 271ML-46 120.3 0.5 0.22 81 0.5 0.38 135 0.5 0.58 196 0.5 0.70 231 0.5 0.96 305ML-46-1 216.6 2 day 32 6 66 6 111 6 132 6 174ML-45 95.4 0.5 0.22 76 0.5 0.39 125 0.5 0.60 180 0.5 0.73 207 0.5 1.00 267ML-45-1 312.0 0.5 61 6 91 6 131 6 141 6 164ML-44 129.3 0.5 0.15 110 0.5 0.25 163 0.5 0.39 219 0.5 0.49 246 0.5 0.7 297ML-44-1 441.3 2 day 39 2 day 57 2 day 75 2 day 85 2 day 104ML-43 43.9 0.5 0.58 100 0.5 0.88 162 0.5 1.21 232 0.5 1.39 269 0.5 1.75 337ML-43-1 43.9 1 24 1 27 1 30 1 31 1 73ML-42 108.2 0.5 0.30 105 0.5 0.50 174 0.5 0.74 249 0.5 0.87 294 0.5 1.16 376ML-42-1 108.2 1 15 3 18 6 20 12 22 12 43ML-41 53.1 1 0.31 30 0.5 0.37 49 0.5 0.58 72 0.5 0.71 85 0.5 0.97 113ML-41-1 205.2 1 49 6 66 6 89 6 101 1 165ML-40 32.0 3 0.50 8 1 0.57 15 1 0.88 28 1 1.05 36 1 1.42 55ML-40-1 32.0 6 2 2 day 4 2 day 6 2 day 7 2 day 9ML-39 35.2 0.5 0.36 52 0.5 0.56 86 0.5 0.80 121 0.5 0.94 139 0.5 1.22 174ML-39-1 67.2 24 4 2 day 7 24 9 24 10 2 day 13ML-37 31.0 0.5 0.27 32 0.5 0.45 53 0.5 0.69 75 0.5 0.82 86 0.5 1.11 110ML-38 53.4 0.5 0.42 108 0.5 0.66 175 0.5 0.94 245 0.5 1.10 276 0.5 1.42 346ML-38-1 84.4 2 day 7 2 day 11 12 14 2 day 15 2 day 48ML-35 74.7 1 0.60 84 1 0.94 133 0.5 0.98 186 0.5 1.13 216 0.5 1.44 281ML-35-1 74.7 2 day 4 2 day 6 2 day 7 12 7 24 8ML-36B 25.5 0.5 0.36 44 0.5 0.57 72 0.5 0.83 100 0.5 0.97 114 0.5 1.27 140ML-36-2 25.5 0.5 25 0.5 27 0.5 29 0.5 31 1 34ML-36A 29.3 0.5 0.36 57 0.5 0.56 89 0.5 0.80 120 0.5 0.94 134 0.5 1.22 168ML-36-1 29.3 0.5 41 0.5 52 0.5 64 0.5 66 0.5 70ML-34 71.3 1 0.58 79 1 0.92 124 0.5 0.96 178 0.5 1.11 206 0.5 1.44 266ML-34-1 200.8 1 87 1 110 1 141 1 158 1 213ML-33 59.2 0.5 0.27 68 0.5 0.42 109 0.5 0.61 153 0.5 0.72 177 0.5 0.97 224ML-33-1 59.2 1 13 6 20 6 32 6 38 6 50ML-32 44.2 0.5 0.16 34 0.5 0.28 55 0.5 0.46 77 0.5 0.57 83 0.5 0.80 104ML-32-1 103.4 2 day 11 12 18 12 24 12 26 12 29ML-31 76.2 0.5 0.15 37 0.5 0.26 63 0.5 0.43 90 0.5 0.53 104 0.5 0.75 137ML-31-1 179.6 1 55 1 77 6 111 6 131 6 170ML-30 23.7 0.5 0.05 3 6 0.64 7 6 1.11 14 6 1.38 18 6 1.97 26ML-30-1 23.7 12 2 2 day 5 3 5 3 5 1 5RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-77

LOCATIONAREA(ac)Table 4.4.6 Lake Marion District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(hr)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)ML-29 91.5 0.5 0.22 90 0.5 0.38 143 0.5 0.58 201 0.5 0.70 231 0.5 0.96 289ML-28 97.3 0.5 0.10 28 0.5 0.17 46 0.5 0.30 68 0.5 0.39 80 0.5 0.58 105ML-27 90.2 0.5 0.17 70 0.5 0.29 112 0.5 0.46 152 0.5 0.56 178 0.5 0.80 219ML-26 94.1 0.5 0.15 44 0.5 0.22 72 0.5 0.33 101 0.5 0.41 116 0.5 0.58 146ML-25 145.9 0.5 0.02 9 2 day 0.66 17 2 day 1.28 36 2 day 1.65 47 2 day 2.47 69ML-25-1 330.2 1 38 2 day 56 2 day 68 2 day 75 2 day 89ML-24A 74.9 0.5 0.45 117 0.5 0.67 194 0.5 0.91 276 0.5 1.03 319 0.5 1.31 409ML-24-1 74.9 6 11 6 16 6 23 6 27 6 36ML-24B 39.7 0.5 0.53 73 0.5 0.79 120 0.5 1.07 171 0.5 1.22 196 0.5 1.54 255ML-24-2 39.7 6 7 6 10 6 12 6 13 6 15ML-24C 24.3 0.5 0.61 59 0.5 0.91 98 0.5 1.22 139 0.5 1.39 159 0.5 1.73 202ML-24-3 24.3 0.5 33 0.5 41 1 47 0.5 48 0.5 52ML-1 1111.7 0.5 0.60 2457 0.5 0.92 4063 0.5 1.27 5826 0.5 1.45 6708 0.5 1.83 8560ML-1-1 4982 10 day 0 10 day 2 10 day 17 10 day 23 10 day 36**This pond remains landlocked for this case.RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)CRIT.EVENT(hr)RUNOFF(in)PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-78

PONDNAMENWLTable 4.4.7 Lake Marion District: Proposed Conditions – Peak Discharges and ElevationsPEAKELEV.(ft)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)ML-1-1 1 978.8 981.4 1703 0 982.2 2203 2 983.0 2676 17 983.4 2894 23 984.1 3358 36ML-1-1 2 978.8 982.0 983.8 984.5 985.8ML-2-1 978.8 980.5 * * 981.4 * * 982.3 * * 982.6 * * 983.4 * *ML-3-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-3-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-3-3 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-4-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-7-1 1028.0 1030.4 4.5 63 1031.6 6.8 95 1032.6 9.8 135 1033.1 11.5 157 1034.0 14.9 201ML-8-1 1053.0 1054.9 0.1 53 1055.8 0.2 87 1057.1 0.2 125 1057.6 0.3 140 1058.1 0.4 183ML-9-1 1098.0 1099.2 2.5 5 1100.2 4.6 9 1101.5 7.6 11 1102.1 9.3 12 1103.5 12.9 14ML-10-1 1054.0 1055.3 2.8 8 1056.3 4.8 14 1057.3 7.1 21 1057.8 8.3 24 1058.8 11.1 29ML-11-1 1005.5 1007.4 1.6 19 1008.2 2.4 28 1008.7 3.3 37 1009.0 3.7 41 1009.7 4.8 52ML-12-1 1090.9 1094.1 3.6 27 1095.5 6.9 40 1097.3 11.6 55 1098.2 14.9 61 1100.1 22.2 72ML-12-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-13-1 978.8 980.5 * * 981.4 * * 982.3 * * 982.6 * * 983.4 * *ML-14-1 1002.0 1002.4 2.0 2 1002.7 3.4 3 1003.0 5.1 4 1003.2 6.0 5 1003.6 8.0 6ML-17-1 988.2 992.6 1.7 107 993.6 2.3 171 994.6 3.0 232 995.1 3.3 265 996.1 4.0 324ML-18-1 1007.5 1008.4 2.1 6 1009.2 3.8 12 1010.0 5.7 17 1010.4 6.9 19 1011.1 9.4 23ML-19-1 1012.0 1016.0 8.9 88 1017.2 11.9 127 1018.2 14.6 160 1018.7 16.1 175 1019.6 18.5 200ML-20-1 1037.0 1041.2 11.5 86 1042.4 17.7 118 1043.6 25.1 147 1044.1 28.7 161 1045.1 36.9 179ML-22-1 1067.8 1072.1 4.7 51 1072.9 13.0 59 1074.0 25.4 70 1074.3 32.7 73 1074.9 49.5 78ML-22-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-23-1 1077.0 1079.5 2.5 16 1080.8 5.5 24 1082.3 9.5 31 1082.8 11.9 33 1083.9 17.2 37ML-23-2 1070.0 1070.2 1.9 7 1070.4 2.4 8 1071.2 3.9 9 1071.6 4.8 10 1072.3 6.8 11ML-24-1 983.0 984.1 3.8 11 984.7 5.6 16 985.3 7.9 23 985.5 9.1 27 986.1 11.6 36ML-24-2 1002.0 1003.4 2.3 7 1004.0 3.5 10 1004.6 5.0 12 1004.8 5.8 13 1005.5 7.6 15ML-24-3 1010.8 1014.4 0.4 33 1015.5 0.7 41 1016.2 1.1 47 1016.5 1.3 48 1017.1 1.8 52ML-25-1 988.0 988.7 1.6 38 989.1 2.9 56 990.3 9.2 68 991.0 13.7 75 992.3 24.1 89ML-29-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-30-1 987.9 988.8 0.4 2 989.7 0.8 5 990.5 1.4 5 990.8 1.9 5 991.8 3.0 5ML-31-1 980.0 982.7 0.7 55 984.1 1.6 77 986.0 4.6 111 986.5 5.9 131 987.4 8.4 170ML-32-1 990.0 991.4 2.4 11 992.5 4.7 18 993.8 7.8 24 994.5 9.7 26 995.8 14.3 29ML-33-1 992.4 997.0 1.0 13 997.6 1.7 20 998.5 2.6 32 999.0 3.2 38 1000.1 4.3 50ML-33-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-34-1 990.0 993.7 0.4 87 994.2 0.8 110 994.7 1.5 141 995.0 1.9 158 995.6 2.7 213ML-35-1 1000.0 1001.3 7.9 4 1002.0 12.5 6 1002.8 18.1 7 1003.3 21.1 7 1004.4 27.2 8ML-36-1 1012.7 1016.2 0.2 41 1017 0.3 52 1017.9 0.5 64 1018.2 0.6 66 1018.7 0.9 70ML-36-2 1018.3 1022.2 0.2 25 1022.8 0.4 27 1023.5 0.7 29 1024.0 0.9 31 1024.8 1.5 34ML-37-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-38-1 997.1 998.7 6.6 7 999.8 10.7 11 1000.6 15.3 14 1001.0 18.1 15 1001.3 20.6 48PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-79

PONDNAMENWLTable 4.4.7 Lake Marion District: Proposed Conditions – Peak Discharges and ElevationsPEAKELEV.(ft)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)PEAKFLOW(cfs)PEAKELEV.(ft)STORAGEVOLUME(ac-ft)ML-39-1 983.0 983.4 2.6 4 983.8 4.5 7 984.1 6.6 9 984.3 8.0 10 984.6 10.7 13ML-40-1 981.0 982.1 1.7 2 982.6 3.0 4 983.1 4.4 6 983.3 5.2 7 983.9 6.7 9ML-41-1 999.5 1001.9 0.1 49 1002.5 0.2 66 1003.0 0.4 89 1003.1 0.4 101 1003.3 0.5 165ML-42-1 1023.2 1026.6 3.0 15 1028.2 6.8 18 1029.9 12.0 20 1030.9 14.9 22 1032.2 19.6 43ML-42-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-42-3 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-42-4 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-43-1 1010.9 1015.7 1.4 24 1016.8 2.4 27 1018.1 3.7 30 1018.6 4.4 31 1019.2 5.2 73ML-44-1 978.9 983.3 12.0 39 986.6 26.3 57 989.1 45.8 75 990.0 56.3 85 991.8 77.8 104ML-45-1 996.6 1000.7 0.3 61 1002.6 1.0 91 1006.4 5.3 131 1007.6 8.8 141 1010.4 16.7 164ML-46-1 1050.0 1051.5 4.6 32 1052.6 8.3 66 1053.8 12.2 111 1054.4 14.5 132 1055.7 19.6 174ML-46-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-47-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-48-1 982.1 984.4 17.5 5 985.1 24.4 42 985.3 26.2 90 985.4 26.8 106 985.5 27.8 133ML-49-1 986.6 988.5 0.4 24 989.1 0.6 36 989.8 0.9 49 990.1 1.0 55 990.7 1.5 62ML-49-2 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **ML-50-1 998.0 1001.4 0.9 40 1002.4 1.4 53 1003.3 2.2 64 1004.0 2.8 78 1004.2 2.9 161ML-51-1 980.0 981.0 6.7 9 981.7 12 16 982.5 17.5 27 982.9 20.2 33 983.4 23.1 601 Based on HEC-1 model with normal water level 978.8, which is the historical 50 percent probability level. Normal water level may change with futureincreases in watershed yields and corresponding flood levels.2 Based on frequency distribution of average annual water surface elevations 1946-1991.*This pond is considered part of Marion Lake.**This pond was not included in HEC-1 model; see development plans for additional data.PEAKFLOW(cfs)Lakeville Water Resources Management Plan Page 4-80

CONDITIONTable 4.5.1 North Creek District PONDNET ResultsAVERAGESURFACEINFLOWVOLUME(acre-feet)ESTIMATEDPHOSPHORUSLOAD(Pounds/Year)AVERAGEPHOSPHORUSCONCENTRATION (ppb)PERCENTTOTALPHOSPHORUS REMOVALExisting 1,544 716 171 60Future Conditions2,188 779 131 45with ExistingWetlandsProposed 2,082 613 108 49Lakeville Water Resources Management Plan Page 4-81

SUBWATERSHEDNAMETable 4.5.2 North Creek District: Existing Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHOD USEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSNC_1 87.5 SCS 1.19 _-----_ 10 100.0 75.0 10.0NC-2 24.6 SCS 0.21 1000 0 100.0 71.0 0.0NC_3 96.4 SCS 1.50 700 2 100.0 71.0 1.9NC_4 117.5 SCS 0.87 3000 15 100.0 68.2 14.5NC_5 213.8 SCS 0.55 600 1 100.0 68.0 0.9NC_6 98.4 SCS 0.48 2500 1 100.0 68.0 0.5NC_7 43.6 SCS 0.36 3500 0 100.0 70.0 0.4NC_8 49.5 SCS 0.90 3500 2 100.0 70.0 1.6NC_9 212.6 SCS 0.37 2400 11 100.0 68.2 11.1NC_10 93.0 SCS 1.28 400 1 100.0 68.3 0.7NC_11 60.8 SCS 0.33 1000 3 100.0 76.3 3.0NC_12 410.0 SCS 1.42 * 1 100.0 69.6 1.4NC_13 55.0 SCS 0.36 100 1 100.0 73.3 0.9NC_14 107.4 SCS 0.32 100 6 100.0 67.0 6.2NC_15 83.5 SCS 0.48 1700 3 100.0 68.0 2.9PERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERNC_16 155.6 2100 Kin 2300 28 80.0 63.0 0.0 20.0 98.0 0.0NC_17 294.7 SCS 2.10 1200 2 100.0 71.0 1.9NC_18 58.4 SCS 0.96 3000 2 100.0 71.0 1.6NC_19 51.2 SCS 0.75 1000 2 100.0 68.7 2.2NC_20 64.5 SCS 0.32 3000 2 100.0 69.0 1.9NC_21 130.8 1400 Kin 2000 59 49.0 63.0 0.0 51.0 98.0 0.0NC_22 123.2 SCS 0.44 1300 15 100.0 64.0 15.2NC_23 108.0 SCS 0.59 1000 0 100.0 70.0 0.0NC_24 56.6 SCS 0.23 2500 6 100.0 70.0 5.8NC_25 76.5 SCS 0.83 200 5 100.0 70.0 5.0NC_26 50.4 SCS 0.81 3000 4 100.0 70.0 3.6NC_27 86.8 1800 Kin 4400 26 82.0 61.0 0.0 18.0 98.0 0.0NC_28 139.5 SCS 0.25 1400 5 100.0 70.0 4.9NC-29 223.0 5150 Kin 4400 33 75.0 63.0 0.0 25.0 98.0 0.0NC_30 100.0 4600 Kin 1500 26 82.0 63.0 0.0 18.0 98.0 0.0NC_31 124.8 1600 Kin 4400 25 80.0 61.0 0.0 20.0 98.0 0.0NC_32 167.2 4100 Kin 1500 23 84.0 62.0 0.0 16.0 98.0 0.0NC_33 55.4 1700 Kin 4000 30 79.0 63.0 0.0 21.0 98.0 0.0NC_34 68.9 SCS 0.48 2000 6 100.0 69.5 6.1NC_35 123.1 1900 Kin 4000 27 80.0 68.0 0.0 20.0 98.0 0.0NC_36 91.0 3400 Kin 300 12 90.0 68.0 0.0 10.0 98.0 0.0NC_37 96.6 2900 Kin 1500 16 88.0 60.0 0.0 12.0 98.0 0.0NC_38 65.3 SCS 0.41 ** 16 100.0 66.9 16.1NC_39 96.9 2200 Kin 2400 11 92.0 66.0 0.0 8.0 98.0 0.0NC_40 56.1 1000 Kin 4200 27 80.0 62.0 0.0 20.0 98.0 0.0NC_41 104.5 2300 Kin 2000 21 85.0 69.0 0.0 15.0 98.0 0.0PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-82

SUBWATERSHEDNAMETable 4.5.2 North Creek District: Existing Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHOD USEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERNC_42 63.7 2300 Kin 1000 25 82.0 68.0 0.0 18.0 98.0 0.0NC_43 126.8 1800 Kin 1900 20 86.0 69.0 0.0 14.0 98.0 0.0NC_44 108.8 SCS 0.30 2100 3 100.0 62.0 2.8NC_45 123.9 SCS 0.13 2000 4 100.0 65.0 3.8NC_46 96.7 SCS 0.15 400 3 100.0 68.0 3.1NC_47 48.6 SCS 0.37 1800 6 100.0 77.0 5.6NC_48 87.8 SCS 0.46 1700 1 100.0 70.0 1.1NC_49 41.3 1200 Kin 1200 19 86.4 66.8 0.0 13.6 98.0 0.0NC_50A 23.6 1250 Kin 225 13 88.9 70.5 0.0 11.1 98.0 0.0NC_50B 20.6 SCS 0.26 1100 0 100.0 70.3 0.0NC_50C 9.4 SCS 0.34 500 0 100.0 70.3 0.0NC_50D 64.0 3250 Kin 1200 4 97.1 65.6 0.0 2.9 98.0 0.0NC_51A 21.3 1920 Kin 410 27 81.0 64.5 0.0 19.0 98.0 0.0NC_51B 11.6 1700 Kin 255 4 96.7 73.5 0.0 3.3 98.0 0.0NC_51C/D 22.9 1600 Kin 220 39 68.7 63.0 0.0 31.3 98.0 0.0NC_51E/F 25.8 1700 Kin 300 30 79.0 63.0 0.0 21.0 98.0 0.0NC_51G 32.5 2450 Kin 300 22 84.3 65.2 0.0 15.7 98.0 0.0NC_51H 4.0 450 Kin 250 13 90.2 64.1 0.0 9.8 98.0 0.0NC_51I 15.0 1700 Kin 1400 30 79.0 63.0 0.0 21.0 98.0 0.0NC_51J 10.1 1500 Kin 1700 30 79.0 63.0 0.0 21.0 98.0 0.0NC_52 40.7 1100 Kin 3000 15 88.0 60.0 0.0 12.0 98.0 0.0NC_53 66.8 2200 Kin 1000 14 90.0 68.0 0.0 10.0 98.0 0.0NC_54 29.4 1600 Kin 3200 31 78.0 64.0 0.0 22.0 98.0 0.0NC_55 77.6 2000 Kin 900 10 93.0 67.0 0.0 7.0 98.0 0.0NC_56 120.5 2700 Kin 1800 14 90.0 69.0 0.0 10.0 98.0 0.0NC_57 39.9 2400 Kin 3000 13 91.0 62.0 0.0 9.0 98.0 0.0NC_58 57.9 1500 Kin 3000 21 85.0 63.0 0.0 15.0 98.0 0.0NC_59 43.5 2100 Kin 100 38 70.0 64.0 0.0 30.0 98.0 0.0NC_60 19.6 600 Kin 600 32 74.0 62.0 0.0 26.0 98.0 0.0NC_61 29.3 900 Kin 1500 34 75.0 71.0 0.0 25.0 98.0 0.0NC_62 53.3 2000 Kin 2500 24 81.0 67.0 0.0 19.0 98.0 0.0* This subwatershed remains landlocked for this case.** This subwatershed drains to Apple Valley before re-entering Lakeville.PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-83

LOCATIONDESIGNATIONTOTALDRAINAGEAREA(AC)Table 4.5.3 North Creek District: Existing Conditions – Critical Events and Corresponding RunoffCRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)NC_62 53.3 0.5 0.19 27 0.5 0.35 45 0.5 0.55 65 0.5 0.67 76 0.5 0.93 101NC_62_1 53.3 2_day 3 2_day 19 2_day 28 6 34 6 55NC_60 19.6 0.5 0.26 24 0.5 0.4 40 0.5 0.59 55 0.5 0.7 63 0.5 0.95 77NC_60_1 19.6 24 1 3 1 2_day 2 24 2 6 2NC_61 29.3 0.5 0.27 27 0.5 0.48 45 0.5 0.73 65 0.5 0.87 77 0.5 1.18 99NC_61_1 102.2 6 3 24 6 2_day 38 2_day 49 2_day 65NC_59 43.5 0.5 0.3 66 0.5 0.47 104 0.5 0.69 144 0.5 0.82 161 0.5 1.09 200NC_58 57.9 0.5 0.15 42 0.5 0.25 67 0.5 0.41 94 0.5 0.51 107 0.5 0.72 133NC_58_1 203.6 6 12 6 14 12 15 2_day 40 2_day 149NC_57 39.9 1 0.13 8 1 0.27 13 6 1.13 20 6 1.39 26 6 1.96 39NC_56 120.5 0.5 0.12 40 6 0.95 68 1 0.71 132 1 0.88 180 1 1.25 293NC_56_1 363.9 6 43 6 68 1 154 1 206 1 313NC_55 77.6 0.5 0.08 15 6 0.8 35 6 1.33 64 1 0.74 83 1 1.08 142NC_54 29.4 0.5 0.22 25 0.5 0.36 40 0.5 0.55 56 0.5 0.66 64 0.5 0.91 83NC_53 66.8 0.5 0.11 22 0.5 0.24 36 6 1.46 56 6 1.77 70 1 1.2 116NC_52 40.7 0.5 0.12 25 0.5 0.19 40 0.5 0.31 54 0.5 0.39 61 0.5 0.57 75NC_52_1 40.7 6 2 2_day 5 12 7 12 8 2_day 10NC_51J 10.1 0.5 0.21 13 0.5 0.34 19 0.5 0.52 25 0.5 0.62 28 0.5 0.86 34NC_51I 15.0 0.5 0.21 18 0.5 0.34 27 0.5 0.52 36 0.5 0.62 41 0.5 0.86 50NC_51H 4.0 0.5 0.1 2 0.5 0.19 3 0.5 0.34 5 0.5 0.43 5 1 1.02 7NC_51_4 4.0 6 1 0.5 1 1 2 1 2 1 3NC_51EF 25.8 0.5 0.21 31 0.5 0.34 47 0.5 0.52 62 0.5 0.62 70 0.5 0.86 86NC_51G 32.5 0.5 0.16 24 0.5 0.28 37 0.5 0.46 52 0.5 0.57 58 0.5 0.8 74NC_51_3 87.4 1 15 6 29 6 55 6 70 6 101NC_51CD 22.9 0.5 0.31 25 0.5 0.48 41 0.5 0.7 58 0.5 0.82 68 0.5 1.09 87NC_51B 11.6 6 0.49 3 6 1.02 6 6 1.64 11 3 1.53 13 1 1.35 20NC_51_2 121.9 1 19 6 35 6 69 6 88 6 131NC_51A 21.3 0.5 0.19 19 0.5 0.32 30 0.5 0.51 42 0.5 0.61 46 0.5 0.86 60NC_51_1 143.2 6 21 6 38 6 68 6 89 6 133NC_50A 23.6 0.5 0.14 13 0.5 0.29 20 0.5 0.5 28 0.5 0.62 32 0.5 0.89 41NC_50_1 166.8 2_day 21 2_day 39 6 73 6 85 6 120NC_50B 20.6 3 0.22 4 1 0.29 10 1 0.57 20 1 0.73 26 1 1.09 39NC_50_2 20.6 6 4 6 9 6 15 3 18 6 23NC_50C 9.4 3 0.22 2 6 0.79 5 1 0.57 8 1 0.73 11 1 1.09 16NC_50D 64.0 2_day 0.81 9 6 0.65 19 6 1.14 38 6 1.42 49 6 2.02 72NC_50_3 301.5 2_day 33 2_day 65 6 117 6 142 6 194NC_49 41.3 0.5 0.14 24 0.5 0.27 39 0.5 0.45 54 0.5 0.56 61 0.5 0.81 77NC_46 96.7 6 0.34 19 1 0.29 54 1 0.55 109 1 0.7 141 1 1.04 214NC_48 87.7 6 0.35 18 6 0.8 40 6 1.36 67 1 0.74 84 1 1.1 124NC_47 48.6 1 0.28 19 1 0.59 41 1 0.97 68 1 1.18 83 1 1.62 115NC_47_1 1113.5 2_day 124 2_day 229 6 369 6 454 6 778CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-84

LOCATIONDESIGNATIONTOTALDRAINAGEAREA(AC)Table 4.5.3 North Creek District: Existing Conditions – Critical Events and Corresponding RunoffCRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)NC-43 126.8 0.5 0.15 75 0.5 0.3 121 0.5 0.51 170 0.5 0.63 195 0.5 0.89 242NC_45 123.9 2_day 0.79 21 1 0.24 56 1 0.46 119 1 0.6 157 1 0.91 245NC_44 108.8 2_day 0.64 15 6 0.52 33 6 0.95 62 1 0.47 81 1 0.75 129NC_44_1 232.7 2_day 34 6 75 6 131 6 176 1 293NC_42 63.7 0.5 0.19 62 0.5 0.34 95 0.5 0.55 128 0.5 0.67 145 0.5 0.94 179NC_41 104.5 0.5 0.16 49 0.5 0.32 78 0.5 0.53 110 0.5 0.65 128 0.5 0.91 165NC_40 56.1 0.5 0.2 52 0.5 0.32 83 0.5 0.49 112 0.5 0.59 128 0.5 0.81 157NC_40_1 56.1 12 4 2_day 8 2_day 12 12 13 2_day 17NC_39 91.4 0.5 0.08 37 0.5 0.18 58 0.5 0.34 81 0.5 0.44 90 0.5 0.66 113NC_39_1 91.4 2_day 11 2_day 22 2_day 33 6 41 6 51NC_37 96.6 0.5 0.12 60 0.5 0.19 92 0.5 0.31 126 0.5 0.39 145 0.5 0.57 176NC_36 91.0 0.5 0.11 38 0.5 0.24 60 0.5 0.42 84 0.5 0.53 95 0.5 0.77 120NC_35 123.1 0.5 0.21 80 0.5 0.37 129 0.5 0.59 183 0.5 0.71 212 0.5 0.98 275NC_35_1 2099.4 2_day 242 2_day 449 6 638 6 744 6 1119NC_32 167.2 1 0.21 51 1 0.39 83 1 0.64 120 1 0.78 140 1 1.1 186NC-38 65.3 1 0.28 23 1 0.51 42 1 0.80 68 1 0.97 83 1 1.34 116AV-CP-6 497.0 2-day 4 4-day 9 2-day 67 2-day 99 2-day 176NC_31 124.8 1 0.26 71 0.5 0.31 119 0.5 0.47 174 0.5 0.57 201 0.5 0.79 264NC_31_1 621.8 2_day 5 4_day 9 4_day 60 2_day 106 2_day 199NC_33 55.4 0.5 0.21 32 0.5 0.34 54 0.5 0.52 79 0.5 0.62 93 0.5 0.86 125NC_30 100.0 1 0.24 23 1 0.44 39 6 1.43 67 6 1.72 84 1 1.19 125NC_34 74.4 6 0.45 16 6 0.92 34 1 0.69 58 1 0.84 77 1 1.22 112NC_34_1 74.4 2-day 12 6 19 6 25 6 27 6 73NC_28 139.5 6 0.42 34 1 0.37 85 1 0.66 158 1 0.83 199 1 1.19 292NC_28_1 213.9 2_day 21 2_day 38 2_day 52 2_day 59 12 113NC_27 86.8 1 0.24 37 1 0.41 57 0.5 0.44 80 0.5 0.53 93 0.5 0.74 120NC_27_1 3344.5 2_day 315 2_day 578 12 811 6 956 6 1350NC_24 56.6 1 0.17 14 1 0.38 37 1 0.68 68 1 0.85 86 1 1.22 125NC_23 108.0 6 0.33 20 6 0.78 46 6 1.33 77 6 1.64 94 6 2.29 130NC_29 223.0 1 0.33 70 1 0.56 122 1 0.85 192 1 1.02 234 1 1.37 336NC_26 50.4 6 0.4 10 6 0.86 21 6 1.43 34 6 1.74 42 6 2.4 57NC_26_1 50.4 12 6 2_day 12 6 25 6 38 6 56NC_22 134.1 1 0.25 37 1 0.44 70 1 0.7 117 1 0.85 144 1 1.19 204NC_25 65.6 6 0.43 13 6 0.9 28 6 1.47 45 6 1.78 55 6 2.44 75NC_19 51.2 6 0.34 9 6 0.78 20 6 1.33 34 6 1.63 41 6 2.28 57NC_21 130.8 1 0.66 158 0.5 0.76 246 0.5 1.06 340 0.5 1.21 389 0.5 1.54 488NC_21_1 4164.2 2_day 382 2_day 677 2_day 849 2_day 1042 12 1592NC_20 64.5 6 0.34 13 6 0.78 30 1 0.56 56 1 0.71 72 1 1.06 108NC_20_1 4228.7 2_day 375 2_day 674 2_day 856 2_day 1037 12 1578NC_18 58.4 6 0.39 11 6 0.86 23 6 1.44 38 6 1.75 46 6 2.42 63NC_17 294.7 2_day 1.03 42 6 0.87 78 6 1.45 128 6 1.76 156 6 2.43 213CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-85

LOCATIONDESIGNATIONTOTALDRAINAGEAREA(AC)Table 4.5.3 North Creek District: Existing Conditions – Critical Events and Corresponding RunoffCRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)AV_CP_1 5718.0 80 80 80 80 80NC_16 155.6 0.5 0.2 96 0.5 0.32 162 0.5 0.5 234 0.5 0.6 268 0.5 0.84 352NC_15 83.5 6 0.33 15 6 0.76 35 6 1.29 59 6 1.58 73 1 1.04 108NC_15_1 5957.1 2_day 112 6 142 6 184 6 199 6 229NC_14 107.4 6 0.37 21 1 0.32 50 1 0.58 94 1 0.73 120 1 1.07 178NC_14_1 107.4 10-day 0 10-day 0 10-day 0 10-day 0 10-day 15NC_13 55.0 6 0.44 14 1 0.38 31 1 0.7 57 1 0.88 72 1 1.27 104NC_13_1 55.0 10-day 0 10-day 6 2_day 9 2_day 24 2_day 47NC-12 410.0 2-day 0.97 63 6 0.81 129 6 1.37 216 6 1.68 262 6 2.33 362NC_11 60.8 1 0.23 21 1 0.52 48 1 0.88 82 1 1.07 101 1 1.5 142NC_11_1 115.8 ** ** ** ** ** ** 30-day 0 ** **NC_10 93.0 2_day 0.85 13 6 0.7 27 6 1.23 47 6 1.52 57 6 2.15 80NC_10_1 93.0 10-day 0 10-day 0 10-day 0 10-day 0 10-day 15NC_9 212.6 1 0.22 60 1 0.44 125 1 0.73 214 1 0.89 265 1 1.25 378NC_9_1 7190.6 2_day 179 2_day 262 2_day 354 2_day 401 2_day 488NC_8 49.5 6 0.36 9 6 0.82 19 6 1.38 32 6 1.68 39 6 2.34 53NC_7 43.6 6 0.34 9 6 0.79 20 1 0.56 37 1 0.72 47 1 1.08 70NC_7_1 43.6 10-day 0 10-day 0 10-day 6 10-day 7 10-day 8NC_6 98.4 2_day 0.84 17 6 0.7 39 6 1.22 68 6 1.51 83 1 0.97 121NC_6_1 98.4 ** ** ** ** ** ** 30-day 0 ** **NC_5 213.8 2_day 0.85 36 6 0.71 83 6 1.23 143 6 1.53 176 6 2.15 247NC_4 117.5 6 0.56 26 6 1.04 52 6 1.61 82 6 1.93 99 6 2.59 133NC_4_1 117.5 6 26 6 37 6 70 6 89 6 132NC_3 96.4 2_day 1.03 15 6 0.87 31 6 1.45 52 6 1.76 63 6 2.43 86NC-2 24.6 6 0.36 6 1 0.31 14 1 0.59 28 1 0.76 36 1 1.13 53NC_1 87.5 6 0.50 19 6 1.04 38 6 1.67 61 6 2.01 73 6 2.73 97NC_1_1 12184.4 2_day 576 2_day 991 2_day 1313 2_day 1496 2_day 2212** This pond remains landlocked for this case. The critical event is the 30-day snowmelt, which is shown for the 100-year frequency event. Other frequency events were not determined for landlockedbasins.CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-86

POND NAMENWL(MSL)Table 4.5.4 North Creek District: Existing Conditions – Peak Discharges and ElevationsPEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)NC_1_1 * 31.0 576 54.0 991 72.0 1313 80.0 1496 97.0 2212NC_4_1 917.0 919.9 0.5 26 920.6 2.1 37 921.1 3.9 70 921.2 4.2 89 921.2 4.6 132NC_6_1 919.0 ** ** 0 ** ** 0 ** ** 0 921.8 73.8 0 ** ** 0NC_7_1 918.1 922.5 10.3 0 923.1 14.5 0 923.2 15.2 6 923.2 15.5 7 923.3 15.8 8NC_9_1 917.2 922.1 187.4 179 922.1 189.4 262 922.2 191.4 354 922.2 192.2 401 922.2 194.2 488NC_10_1 922.0 925.2 20.0 0 926.0 29.5 0 926.5 38.0 0 926.7 43.0 0 927.1 50.5 15NC_11_1 910.0 ** ** 0 ** ** 0 ** ** 0 913.6 45.6 0 ** ** 0NC_13_1 924.0 932.8 12.3 0 933.0 13.1 6 933.0 13.2 9 933.1 13.4 24 933.1 13.6 47NC_14_1 912.0 915.4 25.0 0 916.8 35.5 0 918.1 46.5 0 918.8 51.5 0 920.0 61.2 15NC_15_1 923.0 926.5 5.2 112 927.0 8.2 142 927.9 12.4 184 928.2 15.0 199 929.0 21.6 229NC-20-1 * 17.0 375 30.0 674 36.0 856 41.0 1037 53.0 1578NC_21_1 915.6 919.7 34.5 382 921.7 67.8 677 923.1 127.5 849 923.7 158.6 1042 924.0 183.4 1592NC_26_1 926.5 927.7 1.0 6 928.6 1.9 12 929.6 2.8 25 929.6 2.9 38 929.7 2.9 56NC_27_1 924.8 932.5 7.4 315 932.8 8.6 578 933.0 9.8 811 933.0 10.1 956 933.2 10.8 1350NC_28_1 942.0 943.9 5.9 21 945.5 10.9 38 947.1 16.2 52 947.9 19.1 59 949.2 24.3 103NC_31_1 934.5 935.7 8.8 5 936.8 18.6 9 939.1 43.1 60 939.3 45.1 106 939.6 48.9 199NC_34_1 976.1 977.5 1.2 12 979.0 2.6 19 981.3 4.8 25 982.6 6.2 27 983.4 7.1 73NC_35_1 939.0 942.0 10.2 242 944.0 20.5 449 945.5 40.8 638 946.4 55.4 744 948.3 95.5 1119NC_39_1 969.4 970.7 1.3 11 972.0 2.6 22 973.1 3.9 33 973.8 4.8 41 975.4 7.3 51NC_40_1 1007.5 1008.5 1.9 4 1009.3 3.6 8 1010.2 5.5 12 1010.5 6.6 13 1011.3 8.9 17NC_44_1 968.0 970.0 0.3 34 971.4 1.3 75 972.8 2.8 131 973.1 3.4 176 973.6 4.3 293NC_47_1 975.2 979.3 7.6 124 981.0 18.0 229 982.3 29.9 369 982.9 37.5 454 983.4 44.7 778NC_50_1 1011.0 1013.1 3.7 21 1013.9 5.1 39 1016.0 5.8 73 1016.3 6.9 85 1017.0 9.5 120NC_50_2 1035.5 1036.3 0.1 4 1037.0 0.3 9 1037.7 0.4 15 1038.0 0.5 18 1038.7 0.8 23NC_50_3 1002.0 1002.5 0.5 33 1002.9 0.9 65 1003.3 1.4 117 1003.5 1.7 142 1003.8 2.1 194NC_51_1 1019.0 1021.1 0.6 21 1021.8 1.4 38 1022.5 2.9 68 1022.8 3.7 89 1023.3 5.1 133NC_51_2 1021.0 1023.1 0.7 19 1023.9 2.0 35 1025.8 3.3 69 1026.4 3.8 88 1027.3 4.8 131NC_51_3 1031.0 1032.8 1.0 15 1033.6 1.6 29 1034.3 2.3 55 1034.6 2.5 70 1035.1 3.0 101NC_51_4 1037.0 1037.2 0.0 1 1037.5 0.1 1 1037.8 0.1 2 1038.0 0.2 2 1038.3 0.2 3NC_52_1 1088.0 1088.7 1.1 2 1089.4 2.2 5 1090.2 3.6 7 1090.6 4.4 8 1091.5 6.2 10NC_56_1 1024.1 1027.7 0.2 43 1030.6 1.3 68 1031.2 1.8 154 1031.3 1.9 206 1031.5 2.1 313NC_58_1 1063.0 1066.5 2.9 12 1069.9 7.6 14 1074.3 20.2 15 1074.9 22.8 40 1075.3 24.4 149NC_60_1 1106.0 1106.4 1.5 1 1106.7 2.6 1 1107.1 3.8 2 1107.2 4.4 2 1107.6 5.8 2NC_61_1 1095.0 1096.6 2.1 3 1098.9 6.7 6 1099.3 7.7 38 1099.4 8.1 49 1099.5 8.5 65NC_62_1 1114.6 1117.0 4.7 3 1117.1 5.0 19 1117.2 5.1 28 1117.2 5.2 34 1117.3 5.6 55AV_CP-6 937.0 940.0 19.2 4 944.3 47.6 9 946.0 60.8 67 946.5 65.9 99 947.9 77.8 176PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-87

POND NAMENWL(MSL)Table 4.5.4 North Creek District: Existing Conditions – Peak Discharges and ElevationsPEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)AV_CP_1 *** *** *** 80 *** *** 80 *** *** 80 *** *** 80 *** *** 80* Normal water surface elevation not established for this pond.** This pond remains landlocked for this case. The critical event is the 30-day snowmelt, which is shown for the 100-year frequency event. Other frequency events were not determined forlandlocked basins.*** Constant discharge assumed.PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-88

SUBWATERSHEDNAMETable 4.5.5 North Creek District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERNC_1 87.5 3400 Kin ------- 30 79.0 68.0 0.0 21.0 98.0 0.0NC_2 24.6 1000 Kin ------- 30 79.0 63.0 0.0 21.0 98.0 0.0NC_3 96.4 3100 Kin 700 30 79.0 63.0 0.0 21.0 98.0 0.0NC_4 117.5 2600 Kin 3500 38 71.0 61.0 0.0 29.0 98.0 0.0NC_5 213.8 3200 Kin 600 30 79.0 56.0 0.0 21.0 98.0 0.0NC_6 98.4 1200 Kin 2500 30 79.0 55.0 0.0 21.0 98.0 0.0NC_7 43.6 1200 Kin 3500 30 79.0 61.0 0.0 21.0 98.0 0.0NC_8 49.5 2200 Kin 3500 30 79.0 63.0 0.0 21.0 98.0 0.0NC_9A 156.7 1100 Kin 2400 44 63.0 56.0 0.0 37.0 98.0 0.0NC_9B 24.9 800 Kin 100 34 74.0 42.0 0.0 26.0 98.0 0.0NC_9C 29.5 1700 Kin 100 65 44.0 58.0 0.0 56.0 98.0 0.0NC_10 93.0 1700 Kin 900 30 79.0 57.0 0.0 21.0 98.0 0.0NC_11A 39.6 200 Kin 1300 77 26.0 59.0 0.0 74.0 98.0 0.0NC_11B 19.6 2100 Kin 100 35 73.0 60.0 0.0 27.0 98.0 0.0NC_11C 11.5 600 Kin 100 34 74.0 61.0 0.0 26.0 98.0 0.0NC_12 396.6 3000 Kin * 30 79.0 55.0 0.0 21.0 98.0 0.0NC_13 57.2 1000 Kin 400 33 75.0 51.0 0.0 25.0 98.0 0.0NC_14A 71.7 350 Kin 100 80 24.0 54.0 0.0 76.0 98.0 0.0NC_14B 38.5 2550 Kin 500 61 48.0 51.0 0.0 52.0 98.0 0.0NC_15 83.5 1600 Kin 1700 30 79.0 61.0 0.0 21.0 98.0 0.0NC_16 155.6 2100 Kin 2400 30 79.0 63.0 0.0 21.0 98.0 0.0NC_17 294.7 4100 Kin 1300 30 79.0 63.0 0.0 21.0 98.0 0.0NC_18 58.4 2400 Kin 3000 30 79.0 63.0 0.0 21.0 98.0 0.0NC_19 51.2 2100 Kin 1500 30 79.0 63.0 0.0 21.0 98.0 0.0NC_20 64.5 1800 Kin 3000 30 79.0 64.0 0.0 21.0 98.0 0.0NC_21 130.8 1400 Kin 2000 69 41.0 64.0 0.0 59.0 98.0 0.0NC_22 123.2 3000 Kin 1300 34 75.0 60.0 0.0 25.0 98.0 0.0NC_23 108.0 2100 Kin 1000 31 78.0 61.0 0.0 22.0 98.0 0.0NC_24 56.6 1600 Kin 2500 30 79.0 63.0 0.0 21.0 98.0 0.0NC_25 76.5 3100 Kin 150 33 76.0 64.0 0.0 24.0 98.0 0.0NC_26 42.0 2100 Kin 2000 30 79.0 63.0 0.0 21.0 98.0 0.0NC_27 86.8 1800 Kin 4400 26 82.0 61.0 0.0 18.0 98.0 0.0NC_28 139.5 1600 Kin 1800 30 79.0 62.0 0.0 21.0 98.0 0.0NC_29 231.4 4150 Kin 5400 34 74.0 62.0 0.0 26.0 98.0 0.0NC_30 100.0 4600 Kin 1500 26 82.0 63.0 0.0 18.0 98.0 0.0NC_31 124.8 1600 Kin 4400 39 69.0 63.0 0.0 31.0 98.0 0.0NC_32 167.2 4000 Kin 1500 28 80.0 63.0 0.0 20.0 98.0 0.0NC_33 55.4 1700 Kin 3900 30 79.0 63.0 0.0 21.0 98.0 0.0NC_34 91.4 2400 Kin 2200 36 73.0 63.0 0.0 27.0 98.0 0.0NC_35 123.1 1900 Kin 4000 27 79.0 68.0 0.0 21.0 98.0 0.0NC_36 91.0 3100 Kin 300 44 64.0 64.0 0.0 36.0 98.0 0.0PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-89

SUBWATERSHEDNAMETable 4.5.5 North Creek District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERNC_37 96.6 2600 Kin 1500 31 79.0 63.0 0.0 21.0 98.0 0.0NC_38 65.3 2500 Kin ** 31 78.0 63.0 0.0 22.0 98.0 0.0NC_39 74.4 1900 Kin 2400 31 78.0 64.0 0.0 22.0 98.0 0.0NC_40 56.1 1000 Kin 4200 33 76.0 63.0 0.0 24.0 98.0 0.0NC_41 104.5 2300 Kin 2000 21 85.0 69.0 0.0 15.0 98.0 0.0NC_42 63.7 2100 Kin 1000 30 79.0 63.0 0.0 21.0 98.0 0.0NC_43 126.8 1600 Kin 1900 33 84.0 67.0 0.0 16.0 98.0 0.0NC_44 108.8 2200 Kin 2200 30 79.0 63.0 0.0 21.0 98.0 0.0NC_45 123.9 2600 Kin 2000 30 79.0 63.0 0.0 21.0 98.0 0.0NC_46 96.7 2200 Kin 400 30 79.0 63.0 0.0 21.0 98.0 0.0NC_47 48.6 1400 Kin 1800 30 79.0 71.0 0.0 21.0 98.0 0.0NC_48 87.7 3200 Kin 1500 30 79.0 63.0 0.0 21.0 98.0 0.0NC_49 41.3 1200 Kin 1200 19 86.0 67.0 0.0 14.0 98.0 0.0NC_50A 23.6 1250 Kin 225 13 88.9 70.5 0.0 11.1 98.0 0.0NC_50B 20.6 SCS 0.26 1100 0 100.0 70.3 0.0NC_50C 9.4 SCS 0.34 500 0 100.0 70.3 0.0NC_50D 64.0 3250 Kin 1200 4 97.1 65.6 0.0 2.9 98.0 0.0NC_51A 21.3 1920 Kin 410 27 81.0 64.5 0.0 19.0 98.0 0.0NC_51B 11.6 1700 Kin 255 4 96.7 73.5 0.0 3.3 98.0 0.0NC_51C/D 22.9 1600 Kin 220 39 68.7 63.0 0.0 31.3 98.0 0.0NC_51E/F 25.8 1700 Kin 300 30 79.0 63.0 0.0 21.0 98.0 0.0NC_51G 32.5 2450 Kin 300 22 84.3 65.2 0.0 15.7 98.0 0.0NC_51H 4.0 450 Kin 250 13 90.2 64.1 0.0 9.8 98.0 0.0NC_51I 15.0 1700 Kin 1400 30 79.0 63.0 0.0 21.0 98.0 0.0NC_51J 10.1 1500 Kin 1700 30 79.0 63.0 0.0 21.0 98.0 0.0NC_52 40.7 1100 Kin 4300 34 75.0 64.0 0.0 25.0 98.0 0.0NC_53 66.8 2200 Kin 1000 27 81.0 68.0 0.0 19.0 98.0 0.0NC_54 29.4 1600 Kin 3700 32 77.0 65.0 0.0 23.0 98.0 0.0NC_55 77.6 2000 Kin 900 30 79.0 66.0 0.0 21.0 98.0 0.0NC_56 120.5 2700 Kin 1800 35 75.0 65.0 0.0 25.0 98.0 0.0NC_57 39.9 2200 Kin 3000 30 79.0 65.0 0.0 21.0 98.0 0.0NC_58 57.9 1500 Kin 3200 26 81.0 69.0 0.0 19.0 98.0 0.0NC_59 43.5 2100 Kin 100 38 70.0 64.0 0.0 30.0 98.0 0.0NC_60 19.6 600 Kin 600 34 72.0 62.0 0.0 28.0 98.0 0.0NC_61 29.3 900 Kin 1500 34 75.0 71.0 0.0 25.0 98.0 0.0NC_62 53.3 2000 Kin 2500 34 75.0 69.0 0.0 25.0 98.0 0.0* This pond remains landlocked for this case.** This subwatershed drains to Apple Valley before re-entering Lakeville.PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-90

LOCATIONDESIGNATIONTable 4.5.6 North Creek District: Proposed Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)NC_62 53.3 0.5 0.26 37 0.5 0.45 61 0.5 0.69 87 0.5 0.82 103 0.5 1.12 136NC_62_1 53.3 12 6 6 9 6 27 6 39 6 62NC_60 19.6 0.5 0.28 26 0.5 0.43 42 0.5 0.63 59 0.5 0.74 67 0.5 0.99 84NC_60_1 19.6 24 1 3 1 2 day 2 24 2 6 2NC_61 29.3 0.5 0.27 27 0.5 0.48 45 0.5 0.73 65 0.5 0.87 77 0.5 1.18 99NC_61_1 102.2 2 day 6 2 day 12 2 day 37 2 day 50 6 70NC_59 43.5 0.5 0.3 66 0.5 0.47 104 0.5 0.69 144 0.5 0.82 161 0.5 1.09 200NC_58 57.9 0.5 0.2 53 0.5 0.37 85 0.5 0.59 119 0.5 0.72 136 0.5 0.99 172NC_58_1 203.6 6 13 3 14 2 day 23 2 day 49 2 day 144NC_57 39.9 0.5 0.21 40 0.5 0.35 64 0.5 0.55 88 0.5 0.66 101 0.5 0.91 126NC_56 120.5 0.5 0.25 110 0.5 0.41 179 0.5 0.62 254 0.5 0.74 294 0.5 1 383NC_56_1 363.9 1 67 1 145 0.5 254 0.5 304 0.5 420NC_55 77.6 0.5 0.21 50 0.5 0.36 82 0.5 0.57 119 0.5 0.68 140 0.5 0.94 186NC_54 29.4 0.5 0.23 32 0.5 0.38 52 0.5 0.58 72 0.5 0.7 83 0.5 0.96 104NC_53 66.8 0.5 0.2 45 0.5 0.36 73 0.5 0.57 105 0.5 0.69 120 0.5 0.96 158NC_52 40.7 0.5 0.25 53 0.5 0.4 84 0.5 0.6 113 0.5 0.72 126 0.5 0.98 156NC_52_1 40.7 2 day 4 2 day 7 6 8 6 9 12 11NC_51J 10.1 0.5 0.21 13 0.5 0.34 19 0.5 0.52 25 0.5 0.62 28 0.5 0.86 34NC_51I 15.0 0.5 0.21 18 0.5 0.34 27 0.5 0.52 36 0.5 0.62 41 0.5 0.86 50NC_51H 4.0 0.5 0.1 2 0.5 0.19 3 0.5 0.34 5 0.5 0.43 5 1 1.02 7NC_51_4 4.0 6 1 0.5 1 1 2 1 2 1 3NC_51EF 25.8 0.5 0.21 31 0.5 0.34 47 0.5 0.52 62 0.5 0.62 70 0.5 0.86 86NC_51G 32.5 0.5 0.16 24 0.5 0.28 37 0.5 0.46 52 0.5 0.57 58 0.5 0.8 74NC_51_3 87.4 1 15 6 29 6 55 6 70 6 101NC_51CD 22.9 0.5 0.31 25 0.5 0.48 41 0.5 0.7 58 0.5 0.82 68 0.5 1.09 87NC_51B 11.6 6 0.49 3 6 1.02 6 6 1.64 11 3 1.53 13 1 1.35 20NC_51_2 121.9 1 19 6 35 6 69 6 88 6 131NC_51A 21.3 0.5 0.19 19 0.5 0.32 30 0.5 0.51 42 0.5 0.61 46 0.5 0.86 60NC_51_1 143.2 2 day 22 6 38 6 68 6 89 6 133NC_50A 23.6 0.5 0.14 13 0.5 0.29 20 0.5 0.5 28 0.5 0.62 32 0.5 0.89 41NC_50_1 166.8 2 day 21 2 day 38 6 73 6 85 6 120NC_50B 20.6 3 0.22 4 1 0.29 10 1 0.73 26 1 0.73 26 1 1.09 39NC_50_2 20.6 6 4 6 9 6 15 3 18 6 23NC_50C 9.4 3 0.22 2 6 0.79 5 1 0.57 8 1 0.73 11 1 1.09 16NC_50D 64.0 2 day 0.81 9 6 0.65 19 6 1.14 38 6 1.42 49 6 2.02 72NC_50_3 301.5 2 day 34 2 day 67 6 119 6 145 6 196NC_49 41.3 0.5 0.15 25 0.5 0.28 40 0.5 0.47 56 0.5 0.58 63 0.5 0.82 79NC_46 96.7 0.5 0.21 86 0.5 0.34 139 0.5 0.52 195 0.5 0.62 231 0.5 0.86 286NC_48 87.7 0.5 0.21 71 0.5 0.34 115 0.5 0.52 165 0.5 0.62 191 0.5 0.86 242NC_47 48.6 0.5 0.23 29 0.5 0.43 49 0.5 0.67 71 0.5 0.81 83 0.5 1.1 110NC_47_1 1113.5 2 day 132 2 day 235 6 385 6 469 6 796CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-91

LOCATIONDESIGNATIONTable 4.5.6 North Creek District: Proposed Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)NC_43 126.8 0.5 0.17 78 0.5 0.31 126 0.5 0.5 177 0.5 0.61 204 0.5 0.87 258NC_45 123.9 0.5 0.21 77 0.5 0.34 125 0.5 0.52 178 0.5 0.62 207 0.5 0.86 269NC_44 108.8 0.5 0.21 68 0.5 0.34 111 0.5 0.52 160 0.5 0.62 185 0.5 0.86 240NC_44_1 232.7 1 76 1 114 1 172 1 219 1 326NC_42 63.7 0.5 0.21 73 0.5 0.34 111 0.5 0.52 149 0.5 0.62 168 0.5 0.86 208NC_41 104.5 0.5 0.16 49 0.5 0.32 78 0.5 0.53 110 0.5 0.65 128 0.5 0.91 165NC_40 56.1 0.5 0.24 66 0.5 0.38 102 0.5 0.57 140 0.5 0.68 160 0.5 0.93 198NC_40_1 56.1 2 day 5 2 day 9 12 12 2 day 14 2 day 18NC_39 91.4 0.5 0.22 104 0.5 0.36 165 0.5 0.55 223 0.5 0.66 249 0.5 0.91 309NC_39_1 91.4 6 14 6 27 6 43 6 47 6 56NC_37 96.6 0.5 0.21 109 0.5 0.34 163 0.5 0.52 224 0.5 0.62 254 0.5 0.86 312NC_36 91.0 0.5 0.36 145 0.5 0.56 228 0.5 0.8 318 0.5 0.93 362 0.5 1.22 446NC_35 123.1 0.5 0.22 85 0.5 0.39 136 0.5 0.6 193 0.5 0.73 223 0.5 1 289NC_35_1 2099.4 2 day 265 6 468 6 689 6 781 6 1268NC_32 167.2 1 0.27 66 1 0.48 108 1 0.75 158 1 0.9 187 1 1.24 253NC-38 65.28 0.5 0.22 72 0.5 0.35 114 0.5 0.54 158 0.5 0.64 177 0.5 0.88 219AV_CP-6 497.0 2 day 4 2 day 9 2 day 67 2 day 99 2 day 176NC_31 124.8 0.5 0.31 110 0.5 0.48 185 0.5 0.70 272 0.5 0.82 315 0.5 1.09 411NC_31_1 621.8 2 day 6 4 day 10 2 day 63 2 day 110 2 day 200NC_33 55.4 0.5 0.21 32 0.5 0.34 54 0.5 0.52 79 0.5 0.62 93 0.5 0.86 125NC_30 100.0 1 0.24 23 1 0.44 39 6 1.43 67 6 1.72 84 1 1.19 125NC_34 74.4 0.5 0.29 101 0.5 0.45 163 0.5 0.66 225 0.5 0.78 256 0.5 1 320NC_34_1 74.4 6 10 6 17 6 21 6 23 6 26NC_28 139.5 0.5 0.21 141 0.5 0.33 227 0.5 0.5 319 0.5 0.61 361 0.5 0.83 445NC_28_1 213.9 2 day 20 2 day 36 2 day 49 2 day 56 2 day 68NC_27 86.8 1 0.24 37 1 0.41 57 0.5 0.44 80 0.5 0.53 93 0.5 0.74 120NC_27_1 3344.5 2 day 339 6 611 6 881 6 1022 6 1542NC_24 56.6 0.5 0.21 57 0.5 0.34 91 0.5 0.52 126 0.5 0.62 145 0.5 0.86 181NC_23 108.0 0.5 0.22 112 0.5 0.34 181 0.5 0.51 250 0.5 0.61 285 0.5 0.83 358NC_23_1 164.6 2 day 17 2 day 29 6 78 6 103 6 157NC_29 231.4 0.5 0.26 170 0.5 0.40 280 0.5 0.59 398 0.5 0.70 463 0.5 0.95 598NC_26 42.0 0.5 0.21 27 0.5 0.34 46 0.5 0.52 66 0.5 0.62 75 0.5 0.86 98NC_22 134.1 1 0.32 69 1 0.53 109 1 0.79 153 1 0.94 176 1 1.27 230NC_25 65.6 1 0.33 21 1 0.56 37 1 0.85 57 1 1.02 70 1 1.38 100NC_19 51.2 0.5 0.21 36 0.5 0.34 59 0.5 0.52 86 0.5 0.62 100 0.5 0.86 125NC_19_1 51.2 24 2 2 day 12 2 day 25 2 day 30 6 48NC_21 130.8 1 0.76 184 0.5 0.88 287 0.5 1.21 397 0.5 1.38 454 0.5 1.73 569NC_21_1 4164.2 2 day 402 2 day 679 2 day 850 2 day 1041 12 1635NC_20 64.5 1 0.29 30 1 0.51 47 1 0.79 67 0.5 0.64 77 0.5 0.89 101NC_20_1 4228.7 2 day 395 2 day 677 2 day 857 2 day 1034 12 1618NC_18 58.4 1 0.28 18 1 0.49 30 1 0.77 45 1 0.92 54 1 1.27 74CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-92

LOCATIONDESIGNATIONTable 4.5.6 North Creek District: Proposed Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)NC_17 294.7 0.5 0.21 209 0.5 0.34 335 0.5 0.52 478 0.5 0.62 555 0.5 0.86 700NC_17_1 294.7 2 day 30 2 day 64 6 109 6 196 6 330AV_CP_1 5718.0 0.5 80 0.5 80 0.5 80 0.5 80 0.5 80NC_16 155.6 0.5 0.21 101 0.5 0.34 170 0.5 0.52 248 0.5 0.62 282 0.5 0.86 371NC_15 83.5 1 0.27 45 1 0.47 72 0.5 0.49 103 0.5 0.59 121 0.5 0.81 158NC_15_1 5957.1 3 114 6 142 6 183 6 198 6 228NC_14B 38.5 0.5 0.51 102 0.5 0.76 158 0.5 1.01 212 0.5 1.14 242 0.5 1.42 301NC_14_2 38.5 6 5 6 7 6 9 3 9 3 10NC_9C 29.5 0.5 0.55 56 0.5 0.82 93 0.5 1.11 132 0.5 1.26 154 0.5 1.59 197NC_9_3 29.5 3 5 6 8 6 10 6 11 6 13NC_9B 24.9 0.5 0.26 29 0.5 0.38 46 0.5 0.5 64 0.5 0.56 74 0.5 0.69 93NC_9_2 24.9 1 2 3 3 6 4 3 4 6 6NC_14A 71.7 0.5 0.75 298 0.5 1.11 460 0.5 1.47 614 0.5 1.66 695 0.5 2.05 855NC_14_1 164.6 3 1 2 day 2 12 2 2 day 3 4 day 4NC_13 57.2 0.5 0.25 49 0.5 0.36 81 0.5 0.49 117 0.5 0.56 134 0.5 0.73 172NC_13_1 57.2 3 3 6 5 2 day 9 2 day 10 12 12NC-12 396.6 0.5 0.21 354 0.5 0.31 561 0.5 0.43 784 0.5 0.51 902 0.5 0.69 1123NC_11C 11.5 0.5 0.26 13 0.5 0.4 22 0.5 0.58 30 0.5 0.69 35 0.5 0.93 43NC_11_3 11.5 0.5 1 6 3 3 4 6 5 6 7NC_11B 19.6 0.5 0.27 23 0.5 0.41 36 0.5 0.59 51 0.5 0.69 59 0.5 0.93 73NC_11_2 19.6 1 2 6 4 6 6 6 7 6 9NC_11A 39.6 0.5 0.73 161 0.5 1.08 248 0.5 1.45 132 0.5 1.64 374 0.5 2.03 460NC_11_1 127.9 24 2 24 3 24 4 2 day 5 4 day 6NC_10 93.0 0.5 0.21 72 0.5 0.31 116 0.5 0.45 162 0.5 0.53 190 0.5 0.72 238NC_10_1 93.0 6 5 2 day 11 2 day 19 2 day 22 2 day 49NC_9A 156.7 0.5 0.36 260 0.5 0.54 416 0.5 0.74 569 0.5 0.85 669 0.5 1.1 842NC_9_1 6895.9 4 day 92 4 day 103 4 day 118 4 day 179 2 day 288NC_8 49.5 1 0.28 19 1 0.49 32 1 0.77 46 1 0.92 55 1 1.27 74NC_7 43.6 0.5 0.21 44 0.5 0.32 71 0.5 0.49 100 0.5 0.59 113 0.5 0.81 139NC_7_1 43.6 2 day 4 2 day 10 6 20 6 27 6 40NC_6 98.4 0.5 0.21 93 0.5 0.31 148 0.5 0.43 203 0.5 0.51 237 0.5 0.69 300NC_6_1 98.4 2 day 4 2 day 7 2 day 14 2 day 30 2 day 56NC_5 213.8 0.5 0.21 195 0.5 0.31 312 0.5 0.44 432 0.5 0.52 502 0.5 0.7 627NC_5_1 312.2 6 35 1 75 1 139 1 173 1 242NC_4 117.5 0.5 0.29 129 0.5 0.44 209 0.5 0.64 300 0.5 0.75 346 0.5 1.00 439NC_4_1 117.5 6 21 6 41 6 85 6 110 1 185NC_3 96.4 0.5 0.21 69 0.5 0.34 111 0.5 0.52 159 0.5 0.62 184 0.5 0.86 230NC-2 24.6 0.5 0.21 19 0.5 0.31 31 0.5 0.43 44 0.5 0.51 50 0.5 0.69 64NC_1 87.5 0.5 0.22 62 0.5 0.39 101 0.5 0.6 143 0.5 0.73 167 0.5 1 212NC_1_1 12184.4 2 day 541 2 day 888 2 day 1148 2 day 1323 2 day 2064CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-93

POND NAMENWL(MSL)Table 4.5.7 North Creek District: Proposed Conditions – Peak Discharges and ElevationsPEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)NC_1_1 * * 30 541 * 48 888 * 63 1148 * 72 1323 * 94 2064NC_4_1 917.0 919.7 3.1 21 920.8 4.4 41 921.1 5.1 85 921.2 5.3 110 921.3 5.5 185NC_5_1 916.0 918.1 4.5 35 918.2 4.8 75 918.5 5.3 139 918.6 5.6 173 918.8 6.1 242NC_6_1 920.0 920.7 3.8 4 921.3 7.2 7 922.1 11.1 14 922.4 11.7 30 922.9 12.7 56NC_7_1 920.0 921.2 1.3 4 922.1 2.3 10 922.4 2.6 20 922.5 2.8 27 922.9 3.2 40NC_9_1 917.2 920.9 162.9 92 921.3 187.1 103 921.8 214.0 118 921.9 214.8 179 921.9 216.2 288NC_9_2 920.0 920.5 0.7 2 920.7 1.0 3 920.9 1.4 4 921.0 1.6 4 921.4 2.3 6NC_9_3 930.0 931.2 1.8 5 931.8 2.8 8 932.4 3.9 10 932.7 4.5 11 933.5 5.8 13NC_10_1 922.0 923.3 2.8 5 924.4 5.3 11 925.6 8.1 19 926.2 9.6 22 927.1 12.2 49NC_11_1 919.0 919.5 13.0 2 919.8 20.5 3 920.2 29.6 4 920.4 34.4 5 920.8 44.9 6NC_11_2 920.0 920.5 0.5 2 920.9 0.9 4 921.3 1.5 6 921.6 1.7 7 922.1 2.4 9NC_11_3 920.0 920.3 0.3 1 920.6 0.5 3 920.9 0.8 4 921.1 0.9 5 921.5 1.2 7NC_13_1 920.0 920.7 1.8 3 921.2 3.2 5 921.9 5.0 9 922.3 6.1 10 923.1 8.4 12NC_14_1 918.0 918.6 30.0 1 918.9 41.9 2 919.3 56.9 2 919.4 64.6 3 919.8 80.5 4NC_14_2 920.0 921.2 2.5 5 921.7 3.6 7 922.3 5.0 9 922.7 5.9 9 923.5 7.8 10NC_15_1 923.0 926.5 5.4 114 927.0 8.1 142 927.9 12.3 183 928.2 14.8 198 928.9 21.3 228NC_17_1 922.0 924.0 8.3 30 925.4 14.2 64 926.6 20.2 109 926.8 20.8 196 927.0 21.9 330NC_19_1 920.0 922.9 3.3 2 924.1 4.8 12 924.2 5.1 25 924.3 5.1 30 924.5 5.4 48NC_20_1 * * 18.0 395 * 30.0 677 * 36.0 857 * 41.0 1034 * 54.0 1618NC_21_1 915.6 919.9 35.9 402 921.7 68.0 679 923.1 127.5 850 923.7 158.6 1041 924.0 185.4 1635NC_23_1 925.0 927.1 4.5 17 928.8 8.6 29 929.6 10.5 78 929.9 11.2 103 930.5 12.9 157NC_27_1 924.8 932.5 7.5 339 932.8 8.8 611 933.0 9.9 881 933.1 10.2 1022 933.2 11.2 1542NC_28_1 942.0 943.8 5.7 20 945.3 10.2 36 946.8 15.1 49 947.5 17.8 56 949.0 23.4 68NC_31_1 934.5 936.0 11.1 6 937.0 20.6 10 939.2 43.3 63 939.3 45.2 110 939.6 49.0 200NC_34_1 976.1 977.4 2.8 10 978.4 5.0 17 979.7 8.2 21 980.5 10.2 23 982.2 14.6 26NC_35_1 939.0 942.2 11.3 265 944.2 22.6 468 945.9 46.5 689 946.7 62.2 781 948.5 98.9 1268NC_39_1 969.4 971.1 1.7 14 972.5 3.2 27 974.0 5.1 43 974.7 6.2 47 976.5 9.1 56NC_40_1 1007.5 1008.6 2.2 5 1009.5 3.9 9 1010.3 5.9 12 1010.7 7.0 14 1011.4 9.3 18NC_44_1 968.0 971.5 1.3 76 972.5 2.3 114 973.1 3.4 172 973.3 3.7 219 973.8 4.6 326NC-45-1 ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **NC_47_1 975.2 979.5 8.4 132 981.1 18.4 235 982.4 31.4 385 983.0 38.9 469 983.4 45.0 796NC_50_1 1011.0 1013.1 3.7 21 1013.8 5.0 38 1016.0 5.8 73 1016.3 6.9 85 1017.0 9.5 120NC_50_2 1035.5 1036.3 0.1 4 1037.0 0.3 9 1037.7 0.4 15 1038.0 0.5 18 1038.7 0.8 23NC_50_3 1002.0 1002.6 0.6 34 1002.9 0.9 67 1003.3 1.4 119 1003.5 1.7 145 1003.8 2.1 196NC_51_1 1019.0 1021.2 0.6 22 1021.8 1.4 38 1022.5 2.9 68 1022.8 3.7 89 1023.3 5.1 133NC_51_2 1021.0 1023.1 0.7 19 1023.9 2.0 35 1025.8 3.3 69 1026.4 3.8 88 1027.3 4.8 131NC_51_3 1031.0 1032.8 1.0 15 1033.6 1.6 29 1034.3 2.3 55 1034.6 2.5 70 1035.1 3.0 101NC_51_4 1037.0 1037.2 0.0 1 1037.5 0.1 1 1037.8 0.1 2 1038 0.2 2 1038.3 0.2 3NC_52_1 1088.0 1089.1 1.7 4 1089.9 3.0 7 1090.7 4.6 8 1091.1 5.5 9 1092.0 7.4 11NC_56_1 1024.1 1030.5 1.2 67 1031.2 1.8 145 1031.4 2.0 254 1031.5 2.1 304 1031.7 2.3 420NC_58_1 1063.0 1067.3 3.9 13 1071.1 10.4 14 1074.8 22.2 23 1075.0 23.2 49 1075.3 24.4 144PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-94

POND NAMENWL(MSL)Table 4.5.7 North Creek District: Proposed Conditions – Peak Discharges and ElevationsPEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)NC_60_1 1106.0 1106.4 1.5 1 1106.7 2.6 1 1107.1 3.8 2 1107.3 4.5 2 1107.6 5.8 2NC_61_1 1095.0 1097.9 4.2 6 1099.1 7.1 12 1099.3 7.7 37 1099.4 8.1 50 1099.5 8.6 70NC_62_1 1114.6 1116.1 2.2 6 1116.8 4.0 9 1117.1 4.9 27 1117.2 5.1 39 1117.3 5.6 62AV_CP-6 937.0 939.9 19.0 4 944.2 47.1 9 946 60.8 67 946.5 65.9 99 947.9 77.8 176AV_CP_1 *** *** *** 80 *** *** 80 *** *** 80 *** *** 80 *** *** 80*Normal water surface elevation not established for this pond.**Water quality pond - not included in hydraulic study.***Constant discharge assumed.PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-95

CONDITIONTable 4.6.1 South Creek District PONDNET ResultsAVERAGESURFACEINFLOWVOLUME(acre-feet)ESTIMATEDPHOSPHORUSLOAD(Pounds/Year)Existing Conditions:AVERAGEPHOSPHORUSCONCENTRATION(ppb)PERCENT TOTALPHOSPHORUSREMOVALSC-1 818 668 301 47SC-11 1,695 1,606 349 3130SC-69 135 177 483Future Conditions with Existing Wetlands:SC-1 2,259 1,148 187 22SC-11 5,683 3,292 213 17SC-69 629 365 214 18Proposed Conditions:SC-1 2,259 589 96 60SC-11 5,683 1,579 102 60SC-69 629 179 105 60Lakeville Water Resources Management Plan Page 4-96

SUBWATERSHEDNAMETable 4.6.2 South Creek District: Existing Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSSC-1A 121.0 SCS 0.67 *** 16 100.0 71.4 15.5SC-1B 153.4 SCS 0.64 2000 1 100.0 72.0 0.8PERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERSC-2A 144.6 4200 Kin 2600 44 63.3 70.6 0.0 36.7 98.0 0.0SC-2B 160.0 SCS 0.94 1500 36 100.0 70.3 36.2SC-3A 116.5 3200 Kin 500 43 64.0 68.3 0.0 36.0 98.0 0.0SC-3B 157.4 SCS 0.46 1500 23 100.0 70.1 22.8SC-4A 136.5 SCS 0.72 800 3 100.0 70.4 2.6SC-4B 57.6 SCS 0.28 2800 3 100.0 71.7 2.9SC-5 170.9 SCS 0.44 1200 0 100.0 71.6 1.0SC-6 67.5 SCS 0.41 2300 1 100.0 70.2 1.0SC-7 89.9 SCS 0.96 2200 0 100.0 70.1 0.4SC-8A 49.5 SCS 0.40 500 2 100.0 70.4 1.9SC-8B 114.2 SCS 0.49 2700 2 100.0 70.5 2.0SC-9A 94.1 SCS 0.56 400 1 100.0 68.4 0.5SC-9B 195.0 SCS 0.83 2000 2 100.0 70.6 1.8SC-10A 107.8 SCS 0.46 2000 0 100.0 67.0 0.1SC-10B 530.8 SCS 2.09 200 4 100.0 68.2 4.3SC-11 142.9 SCS 0.27 *** 18 100.0 78.1 17.9SC-12 58.7 SCS 0.22 3000 30 100.0 77.1 30.2SC-13 83.5 SCS 0.11 1300 17 100.0 77.8 16.9SC-14 99.3 4200 Kin 900 45 64.7 77.0 0.0 35.3 98.0 0.0SC-15 100.3 SCS 0.41 1400 15 100.0 69.5 14.7SC-16 90.6 2700 Kin 3500 28 77.5 71.7 0.0 22.5 98.0 0.0SC-17 79.7 SCS 0.51 2300 14 100.0 67.9 14.2SC-18 53.0 SCS 0.51 2500 9 100.0 69.4 9.2SC-19 112.3 SCS 0.41 1400 5 100.0 69.1 5.0SC-20 103.6 SCS 0.69 1900 3 100.0 71.6 3.4SC-21 125.5 SCS 0.91 1500 2 100.0 69.8 2.2SC-22 77.2 SCS 0.40 1500 4 100.0 69.5 4.2SC-23 111.2 SCS 0.55 1500 8 100.0 68.1 8.3SC-24 133.3 SCS 0.43 900 4 100.0 68.3 3.6SC-25 185.2 SCS 0.49 3400 25 100.0 62.9 21.2SC-26 63.4 SCS 0.44 2500 14 100.0 63.8 13.8SC-27 114.3 SCS 1.10 3300 4 100.0 68.9 3.6SC-28 27.1 SCS 0.73 3000 2 100.0 66.4 2.3SC-29 59.7 SCS 0.92 3800 2 100.0 59.8 1.8SC-30 61.5 SCS 0.94 2000 19 100.0 66.0 13.1SC-31A 90.4 SCS 0.43 *** 16 100.0 65.1 16.4SC-31B 10.3 *** 0.0 100.0 58.0 0.0SC-32A 59.8 SCS 0.74 2000 5 100.0 67.8 5.0SC-32B 129.4 SCS 0.73 100 18 100.0 66.7 17.7PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-97

SUBWATERSHEDNAMETable 4.6.2 South Creek District: Existing Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSSC-33 106.4 SCS 0.78 3000 4 100.0 64.4 3.7SC-34 25.1 SCS 0.57 2500 5 100.0 57.3 5.3SC-35 113.6 SCS 0.82 1000 3 100.0 67.3 3.0SC-36 76.2 SCS 1.02 400 4 100.0 69.3 3.7PERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERSC-37 184.5 4000 Kin 2800 25 80.4 61.8 0.0 19.6 98.0 0.0SC-38 136.5 SCS 0.30 3300 6 100.0 59.4 6.0SC-39 41.5 1500 Kin 3800 17 87.8 61.7 0.0 12.2 98.0 0.0SC-40 64.1 2800 Kin 3500 60 46.4 62.9 0.0 53.6 98.0 0.0SC-41 30.0 SCS 0.55 1600 2 100.0 69.5 1.3SC-42 42.6 2200 Kin 550 26 82.9 63.0 0.0 17.1 98.0 0.0SC-43 142.1 SCS 1.04 2000 10 100.0 65.8 8.9SC-44 33.2 SCS 0.94 2100 8 100.0 68.7 8.1SC-45 119.8 SCS 0.49 700 3 100.0 70.5 2.8SC-46 153.7 3700 Kin 1900 13 89.9 67.7 0.0 10.1 98.0 0.0SC-47 116.4 SCS 0.53 3800 6 100.0 64.1 5.5SC-48 74.0 2700 Kin 1000 39 66.6 62.3 0.0 33.4 98.0 0.0SC-49A 34.8 SCS 0.30 1000 8 100.0 63.6 7.5SC-49B 57.0 2400 Kin 900 27 77.1 62.7 0.0 22.9 98.0 0.0SC-50 119.2 SCS 0.84 1500 9 100.0 69.5 8.9SC-51 82.6 SCS 0.24 1300 1 100.0 69.9 1.0SC-52 54.4 SCS 0.59 700 33 100.0 64.0 33.0SC-53 111.8 SCS 0.38 900 6 100.0 70.3 6.2SC-54 49.9 SCS 0.42 1800 2 100.0 72.9 2.3SC-56 148.3 SCS 0.71 500 32 100.0 62.6 31.6SC-57 85.9 SCS 0.50 2300 1 100.0 70.0 1.2SC-58 19.0 SCS 0.22 1500 8 100.0 64.3 8.3SC-59 129.2 SCS 0.44 1900 0 100.0 65.6 0.2SC-60 74.2 SCS 0.42 1900 1 100.0 64.1 0.5SC-61 34.0 SCS 0.27 2300 0 100.0 68.5 0.4SC-62 40.3 SCS 0.32 2300 1 100.0 62.9 1.4SC-63 26.5 SCS 0.29 1400 6 100.0 70.6 6.1SC-64 45.4 SCS 0.35 1400 1 100.0 72.8 0.8SC-65 63.8 SCS 0.35 1300 3 100.0 73.4 2.9SC-66 46.2 SCS 0.30 1100 2 100.0 72.3 2.0SC-67 68.4 SCS 0.41 1300 1 100.0 66.7 1.3SC-68 42.8 SCS 0.15 2400 3 100.0 69.7 2.6SC-69 132.2 SCS 0.81 *** 14 100.0 68.0 13.6SC-70 92.7 SCS 0.72 2000 9 100.0 70.6 8.8SC-71 71.3 SCS 0.40 500 1 100.0 70.3 1.3SC-72 37.9 SCS 0.27 *** 0 100.0 71.1 0.0SC-73 86.5 SCS 0.45 1200 4 100.0 69.9 3.5PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-98

Table 4.6.2 South Creek District: Existing Conditions – Hydrologic and Hydraulic ParametersSUBWATERSHEDNAMEAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSSC-74 58.8 SCS 0.34 1500 3 100.0 69.4 3.3SC-75 55.2 SCS 0.25 1300 5 100.0 71.4 4.8SC-76 67.0 SCS 0.47 1700 4 100.0 67.4 3.6***Runoff from this watershed drains outside of the City of Lakeville.PERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-99

LOCATIONDESIGNATIONNORTHERN CHANNEL:Table 4.6.3 South Creek District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-76 67.0 6 0.33 12 6 0.75 27 6 1.27 47 1 0.69 58 1 1.02 87SC-76-1 67.0 6 12 6 27 6 47 1 58 1 85SC-75 55.2 1 0.17 15 1 0.40 37 1 0.71 68 1 0.89 85 1 1.27 123SC-75-1 55.2 1 15 1 34 1 68 1 85 1 123SC-74 58.8 6 0.38 13 1 0.32 28 1 0.60 53 1 0.76 68 1 1.12 100600 181.0 6 37 6 84 1 147 1 187 1 275SC-73 86.5 6 0.39 19 6 0.86 41 1 0.63 70 1 0.79 88 1 1.15 130SC-73-1 267.5 6 56 6 125 6 198 6 239 1 333SC-71 71.3 6 0.36 15 6 0.82 34 1 0.59 59 1 0.76 76 1 1.12 112SC-70 92.7 6 0.51 22 6 1.01 44 6 1.60 71 6 1.93 85 3 2.05 115SC-70-1 431.5 6 90 6 196 6 311 6 374 6 516SC-69 132.2 6 0.54 29 6 1.02 59 6 1.59 94 6 1.90 113 6 2.56 153601 563.7 6 118 6 253 6 402 6 483 6 666SOUTH CREEK:SC-31A 90.4 1 0.27 30 1 0.48 54 1 0.76 86 1 0.92 105 1 1.27 147SC-31-1 90.4 6 13 6 24 6 38 6 46 6 62SC-62 40.3 2 day 0.63 6 6 0.52 12 6 0.96 23 6 1.21 30 1 0.74 47SC-61 34.0 6 0.30 6 6 0.72 15 1 0.51 29 1 0.66 38 1 1 58608 74.3 2 day 12 6 27 1 50 1 66 1 104SC-60 74.2 2 day 0.65 11 6 0.54 23 6 1 43 6 1.26 54 1 0.78 79609 148.5 2 day 22 6 50 6 92 6 116 1 181SC-59 129.2 2 day 0.71 20 6 0.59 44 6 1.07 80 6 1.34 100 1 0.84 145SC-59-1 277.7 2 day 42 6 95 6 171 6 215 1 324SC-58 19.0 0.5 0.10 5 1 0.31 9 1 0.55 18 1 0.69 23 1 1.01 34SC-58-1 19.0 0.5 5 1 9 1 18 1 23 1 34SC-57 85.9 6 0.35 17 6 0.81 38 6 1.37 65 6 1.67 79 1 1.10 116610 382.6 2 day 59 6 140 6 248 6 309 1 461SC-57-1 382.6 2 day 59 6 140 6 248 6 304 1 457SC-68 42.8 6 0.37 10 1 0.32 27 1 0.60 53 1 0.76 69 1 1.12 103SC-67 68.4 6 0.27 11 6 0.66 26 6 1.17 46 1 0.60 57 1 0.93 87611 111.2 6 20 6 47 1 87 1 111 1 167SC-66 46.2 6 0.44 12 1 0.38 28 1 0.69 52 1 0.87 65 1 1.25 95SC-66-1 46.2 6 12 1 28 1 51 1 65 1 94SC-65 63.8 6 0.49 18 1 0.43 40 1 0.75 72 1 0.94 90 1 1.34 129612 110.0 6 30 1 68 1 123 1 155 1 222SC-64 45.4 6 0.43 12 1 0.37 26 1 0.69 47 1 0.86 59 1 1.25 86613 266.6 6 61 1 138 1 256 1 324 1 472SC-56 148.3 1 0.48 66 1 0.75 101 1 1.06 144 1 1.23 168 1 1.61 219SC-56-1 148.3 6 16 6 28 6 41 6 47 12 68SC-63 26.5 1 0.18 7 1 0.41 17 1 0.71 30 1 0.88 38 1 1.26 54CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-100

LOCATIONDESIGNATIONTable 4.6.3 South Creek District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-54 49.9 6 0.46 13 6 0.97 28 1 0.72 49 1 0.90 61 1 1.30 88614 873.9 6 142 6 321 6 541 6 653 1 952SC-52 54.4 1 0.51 29 1 0.79 45 1 1.12 64 1 1.30 74 1 1.69 97SC-52-1 54.4 3 11 6 23 6 39 6 47 3 64SC-53 111.8 6 0.46 27 1 0.40 61 1 0.70 109 1 0.87 137 1 1.24 197615 1040.1 6 176 6 388 6 657 6 795 6 1127SC-53-1 1040.1 2 day 155 6 351 6 586 6 735 6 999SC-49B 57.0 1 0.31 30 1 0.52 49 0.5 0.55 70 0.5 0.65 82 0.5 0.89 107616 1097.1 2 day 162 6 363 6 609 6 766 6 1049SC-49-2 1097.1 2 day 162 6 345 6 551 6 655 6 937SC-51 82.6 6 0.35 18 1 0.29 43 1 0.57 85 1 0.73 109 1 1.09 163SC-51-1 82.6 2 day 12 6 36 6 67 6 85 1 141SC-50 119.2 6 0.49 25 6 0.97 52 6 1.54 83 6 1.86 101 6 2.52 137SC-50-1 201.8 6 32 6 62 6 88 6 103 6 115SC-49A 34.8 0.5 0.09 6 1 0.28 14 1 0.51 27 1 0.65 34 1 0.95 52SC-49-1 1333.7 2 day 194 6 410 6 634 6 744 6 1054SC-48 74.0 1 0.44 46 1 0.70 79 1 1.02 114 1 1.20 132 1 1.57 172SC-47 116.4 2 day 0.80 17 6 0.67 40 6 1.15 70 6 1.42 87 1 0.92 123618 1524.1 2 day 216 6 450 6 692 6 812 6 1156SC-45 119.8 6 0.40 26 6 0.87 57 6 1.44 94 1 0.80 118 1 1.17 173SC-46 153.7 1 0.18 34 1 0.39 56 6 1.45 92 6 1.75 118 6 2.40 174619 1797.6 2 day 249 6 518 6 795 6 943 6 1304SC-46-1 1797.6 2 day 239 2 day 438 6 743 6 886 6 1284SC-14 99.3 1 0.59 80 1 0.99 147 1 1.43 238 1 1.67 290 1 2.16 403SC-29 59.7 2 day 0.52 6 2 day 1.20 13 6 0.81 23 6 1.04 29 6 1.56 43SC-29-1 59.7 2 day 5 2 day 12 6 20 6 25 6 37SC-34 25.1 0.5 0.06 2 6 0.44 5 6 0.81 10 6 1.03 13 6 1.52 20620 84.8 2 day 7 2 day 16 6 27 6 34 6 51SC-33 106.4 2 day 0.76 15 6 0.63 32 6 1.11 57 6 1.38 71 6 1.97 101SC-33-1 191.2 2 day 20 2 day 41 6 58 6 70 6 79SC-32A 59.8 6 0.37 10 6 0.80 23 6 1.34 39 6 1.63 47 6 2.27 66SC-32-1 251.0 2 day 28 2 day 56 6 79 6 93 6 124SC-32B 129.4 1 0.30 35 1 0.54 62 1 0.83 97 1 1 117 1 1.37 161SC-30 61.5 6 0.49 12 6 0.93 24 6 1.47 38 6 1.77 46 6 2.41 63SC-28 27.1 6 0.28 4 6 0.67 9 6 1.18 16 6 1.46 20 6 2.07 28SC-28-1 27.1 6 4 6 9 6 16 6 20 6 28SC-27 114.3 6 0.37 18 6 0.81 40 6 1.36 66 6 1.66 81 6 2.31 111621 202.9 6 32 6 72 6 118 6 142 6 190SC-27-1 202.9 6 32 6 71 6 118 6 142 6 190622 6 32 6 71 6 110 6 116 6 125623 0 0 6 8 6 26 6 64CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-101

LOCATIONDESIGNATIONTable 4.6.3 South Creek District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-26 63.4 1 0.23 17 1 0.41 31 1 0.66 52 1 0.81 64 1 1.14 92SC-26-1 63.4 1 14 1 26 1 41 6 54 6 81SC-25 185.2 1 0.33 72 1 0.54 116 1 0.82 176 1 0.97 211 1 1.32 288SC-25-1 451.5 2 day 67 6 148 6 246 6 292 6 379SC-24 133.3 6 0.35 26 6 0.79 58 1 0.57 100 1 0.72 128 1 1.07 190SC-24-1 965.2 2 day 126 6 283 6 475 6 571 6 768SC-23 111.2 6 0.44 23 6 0.89 50 6 1.45 83 1 0.83 103 1 1.18 148624 1076.4 2 day 139 6 319 6 542 6 654 6 886SC-23-1 1076.4 2 day 137 6 308 6 522 6 632 6 859SC-22 77.2 6 0.40 17 6 0.85 37 1 0.63 66 1 0.79 84 1 1.15 123625 1153.6 2 day 142 6 319 6 547 6 666 6 914SC-22-1 1153.6 2 day 141 6 314 6 533 6 650 6 895SC-21 125.5 6 0.37 22 6 0.82 48 6 1.38 80 6 1.69 97 6 2.34 134SC-20 103.6 6 0.44 23 6 0.93 48 6 1.52 79 6 1.85 95 6 2.53 129626 1382.7 2 day 166 2 day 364 6 621 6 765 6 1073SC-20-1 1382.7 2 day 164 2 day 362 6 608 6 749 6 1049SC-19 112.3 6 0.40 24 6 0.86 53 1 0.63 95 1 0.79 120 1 1.15 176SC-19-1 1495.0 2 day 172 2 day 373 6 602 6 742 6 1050SC-18 53.0 6 0.49 13 1 0.43 26 1 0.73 45 1 0.90 56 1 1.27 80627 1548.0 2 day 176 2 day 378 12 610 6 746 6 1058SC-39 41.5 0.5 0.12 25 0.5 0.20 40 0.5 0.34 54 0.5 0.42 62 0.5 0.62 76SC-39-1 41.5 2 day 4 2 day 9 2 day 14 6 15 6 17SC-38 136.5 0.5 0.07 20 6 0.52 38 1 0.37 73 1 0.48 97 1 0.73 154SC-38-1 136.5 2 day 3 2 day 7 24 10 2 day 11 2 day 13SC-37 184.5 0.5 0.19 153 0.5 0.31 241 0.5 0.48 335 0.5 0.57 382 0.5 0.80 488628 362.5 0.5 153 0.5 241 0.5 335 0.5 382 0.5 488SC-37-1 362.5 2 day 5 2 day 7 2 day 46 2 day 71 2 day 145SC-36 76.2 6 0.38 13 6 0.83 28 6 1.39 46 6 1.69 56 6 2.35 78SC-36-1 438.7 2 day 17 6 32 2 day 59 2 day 106 2 day 191SC-35 113.6 2 day 0.87 18 6 0.73 40 6 1.25 68 6 1.54 83 6 2.17 116SC-17 79.7 1 0.26 23 1 0.49 45 1 0.79 73 1 0.96 89 1 1.33 124SC-17-1 2180.0 2 day 185 2 day 370 2 day 525 2 day 861 12 1190SC-16 90.6 1 0.37 53 0.5 0.46 87 0.5 0.71 130 0.5 0.85 155 0.5 1.16 212630 2270.6 2 day 191 2 day 380 2 day 537 2 day 811 12 1217SC-44 33.2 6 0.45 6 6 0.91 13 6 1.47 21 6 1.78 26 6 2.44 35Lake Marion 0 0 30 40 50SC-43 142.1 6 0.40 22 6 0.82 48 6 1.34 80 6 1.63 97 6 2.25 135SC-43-1 175.3 6 28 6 59 6 103 6 115 6 133SC-42 42.6 0.5 0.17 29 0.5 0.28 46 0.5 0.45 65 0.5 0.55 75 0.5 0.77 92SC-41 30.0 6 0.34 6 6 0.79 13 6 1.34 22 6 1.64 26 1 1.08 37SC-41-1 247.9 2 day 33 12 52 2 day 83 2 day 111 2 day 141CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-102

LOCATIONDESIGNATIONTable 4.6.3 South Creek District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-40 64.1 1 0.69 96 0.5 0.80 158 0.5 1.10 228 0.5 1.26 266 0.5 1.60 346632 312.0 1 103 0.5 166 0.5 240 0.5 278 0.5 359SC-15 100.3 1 0.29 36 1 0.54 69 1 0.85 112 1 1.03 137 1 1.42 190SC-15-1 2682.9 2 day 227 2 day 440 2 day 636 2 day 891 12 1267SC-13 83.5 0.5 0.30 80 0.5 0.54 154 0.5 0.84 245 0.5 1 295 0.5 1.35 404634 4663.3 2 day 458 2 day 841 2 day 1257 2 day 1485 12 2191SC-12 58.7 0.5 0.43 62 0.5 0.71 103 0.5 1.03 151 1 1.66 177 1 2.14 232SC-12-1 4722.0 2 day 460 2 day 839 2 day 1234 2 day 1494 12 2183SC-11 142.9 1 0.46 104 1 0.82 193 1 1.24 296 1 1.47 353 1 1.94 471635 4864.9 2 day 472 2 day 859 2 day 1261 2 day 1518 2 day 2217SOUTHERN CHANNEL:SC-10B 530.8 2 day 0.95 22 2 day 1.86 42 2 day 1.34 71 2 day 1.64 87 2 day 2.28 170SC-10A 107.8 2 day 0.78 18 6 0.65 40 6 1.15 71 6 1.43 88 1 0.91 127602 638.6 2 day 25 2 day 51 2 day 80 2 day 98 2 day 186SC-9A 94.1 6 0.30 16 6 0.72 37 6 1.25 64 6 1.54 78 6 2.17 109603 732.7 2 day 40 2 day 79 6 136 6 168 6 236SC-9B 195.0 2 day 0.38 20 2 day 0.85 37 2 day 1.42 58 2 day 1.73 70 12 2.40 96SC-9-1 927.7 2 day 48 2 day 94 2 day 146 2 day 176 2 day 258SC-8B 114.2 6 0.38 24 6 0.85 54 6 1.42 89 1 0.78 110 1 1.15 162604 1041.9 2 day 59 2 day 114 2 day 177 2 day 211 2 day 283SC-7 89.9 6 0.34 15 6 0.79 33 6 1.35 56 6 1.66 68 6 2.31 94SC-7-1 89.9 2 day 14 6 25 6 37 6 57 6 87SC-8A 49.5 6 0.38 11 6 0.84 24 1 0.61 42 1 0.78 54 1 1.14 79SC-8-1 49.5 2 day 9 6 18 6 30 6 36 6 50SC-6 67.5 6 0.36 14 6 0.81 32 1 0.58 55 1 0.75 70 1 1.11 103SC-6-1 206.9 2 day 31 6 62 6 97 6 115 6 177SC-5 170.9 6 0.40 39 6 0.88 86 1 0.64 145 1 0.81 184 1 1.19 269SC-4A 136.5 6 0.39 27 6 0.86 59 6 1.43 97 6 1.74 117 6 2.40 161SC-4B 57.6 6 0.44 15 1 0.38 36 1 0.68 65 1 0.86 82 1 1.24 120SC-4-1 1613.8 2 day 112 2 day 216 2 day 256 2 day 266 2 day 292SC-3A 116.5 1 0.50 106 1 0.83 175 0.5 0.86 260 0.5 1.01 309 0.5 1.32 413SC-3B 157.4 1 0.41 77 1 0.70 133 1 1.05 202 1 1.24 240 1 1.65 323605 1887.7 1 155 2 day 257 2 day 390 2 day 427 1 550SC-3-1 1887.7 2 day 134 2 day 247 2 day 336 2 day 375 2 day 482SC-2B 160.0 1 0.60 70 1 0.94 111 1 1.34 158 1 1.55 183 1 2 236SC-2A 144.6 0.5 0.38 164 0.5 0.63 275 0.5 0.91 401 0.5 1.07 472 0.5 1.40 640606 2192.3 6 194 6 315 2 day 461 6 536 6 754SC-2-1 2192.3 6 191 6 311 2 day 448 2 day 508 6 679SC-1B 153.4 6 0.41 33 6 0.90 72 6 1.48 118 6 1.80 143 6 2.49 195SC-1A 121.0 1 0.32 37 1 0.59 69 1 0.93 109 1 1.12 132 1 1.53 180607 2466.7 6 255 6 438 6 627 6 716 6 925CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-103

PONDNAMENWL(MSL)PEAKELEV.(FT)Table 4.6.4 South Creek District: Existing Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)SC-2-1 934.5 936.4 1.2 191 937.3 3.0 311 938.2 6.8 448 938.5 9.8 508 939.3 18.4 679SC-3-1 942.0 945.6 7.7 134 947.6 17.7 247 949.1 25.5 336 949.5 28.6 375 949.7 30.4 482SC-4-1 959.0 963.7 18.9 112 965.4 38.5 216 966.3 69.5 256 966.8 95.5 266 968.2 169.4 292SC-6-1 969.7 970.0 4.6 31 970.1 4.9 62 970.1 5.2 97 970.2 5.3 115 970.3 5.9 177SC-7-1 987.0 989.0 0.4 14 990.2 1.2 25 991.3 3.3 37 991.4 3.6 57 991.6 4.1 87SC-8-1 974.5 974.6 19.5 9 974.7 20.1 18 974.8 20.8 30 974.9 21.2 36 975.0 22.0 50SC-9-1 983.9 985.4 3.2 48 986.3 8.2 94 987.2 14.0 146 987.8 17.3 176 989.2 26.4 258SC-12-1 934.0 936.8 22.4 460 938.8 34.6 839 941.0 54.1 1234 941.7 68.3 1494 942.0 78.3 2183SC-15-1 942.0 946.9 14.1 227 948.2 22.4 440 949.0 29.6 636 950.1 40.5 891 951.8 57.5 1267SC-17-1 962.0 966.2 22.0 185 968.0 47.0 370 969.9 83.9 525 970.1 87.6 861 970.3 90.4 1190SC-19-1 982.8 984.9 2.8 172 986.3 7.1 373 987.3 11.3 602 987.9 13.9 742 989.4 18.8 1050SC-20-1 996.0 997.6 3.1 164 999.2 6.8 362 999.6 10.8 608 999.8 13.2 749 1000.2 17.9 1049SC-22-1 1003.0 1004.7 1.4 141 1006.8 3.0 314 1007.2 6.6 533 1007.4 8.5 650 1007.7 12.3 895SC-23-1 1012.0 1013.7 1.7 137 1015.8 3.9 308 1016.6 7.8 522 1017.0 9.9 632 1017.6 13.9 859SC-24-1 1013.3 1016.2 0.3 126 1017.6 0.4 283 1019.5 0.6 475 1020.1 0.8 571 1021.0 1.5 768SC-25-1 1045.7 1049.9 9.1 67 1050.1 10.0 148 1050.2 10.5 246 1050.2 10.8 292 1050.3 11.3 379SC-26-1 1080.9 1082.1 0.3 14 1083.0 0.5 26 1084.2 0.9 41 1085.1 1.6 54 1087.5 4.7 81SC-27-1 1092.8 1094.5 0.3 32 1095.6 0.6 71 1096.6 1.0 118 1096.9 1.1 142 1097.2 1.3 190SC-28-1 1123.0 1123.0 0.1 4 1123.1 0.2 9 1123.2 0.2 16 1123.2 0.2 20 1123.3 0.3 28SC-29-1 1121.0 1121.1 16.6 5 1121.1 16.9 12 1121.2 17.3 20 1121.2 17.5 25 1121.4 18.1 37SC-31-1 1106.7 1106.9 1.8 13 1107.1 3.5 24 1107.3 5.4 38 1107.5 6.5 46 1107.7 8.8 62SC-32-1 1044.0 1047.0 0.0 28 1049.1 0.1 56 1049.2 0.1 79 1049.3 0.1 93 1049.5 0.1 124SC-33-1 1086.8 1088.4 0.4 20 1090.1 0.9 41 1091.2 2.9 58 1092.0 4.3 70 1093.1 9.1 79SC-36-1 965.7 967.5 0.0 17 968.4 0.2 32 969.5 0.5 59 970.4 0.9 106 970.6 1.1 191SC-37-1 978.3 981.6 15.9 5 984.3 32.8 7 985.1 39.2 46 985.3 40.5 71 985.5 43.3 145SC-38-1 989.3 990.3 5.1 3 991.3 10.6 7 992.6 17.5 10 993.3 21.8 11 994.8 31.1 13SC-39-1 989.9 990.5 0.5 4 991.1 1.0 9 991.8 1.7 14 992.2 2.0 15 993.1 3.3 17SC-41-1 962.7 966.0 2.1 33 967.2 5.7 52 969.9 19.6 83 970.5 24.7 111 971.1 30.1 141SC-43-1 969.8 972.1 0.2 28 973.4 0.9 59 975.8 5.1 103 976.5 8.1 115 977.7 14.9 133SC-46-1 945.4 950.1 12.3 239 952.1 24.5 438 952.6 36.9 743 952.8 41.4 886 953.1 49.9 1284SC-49-1 956.4 959.6 1.2 194 961.3 2.7 410 963.2 5.6 634 964.2 7.9 744 965.9 14.3 1054SC-49-2 962.4 964.9 2.2 162 967.0 5.5 345 969.5 12.9 551 970.6 19.1 655 971.2 29.0 937SC-50-1 969.5 971.2 0.1 32 972.4 2.2 62 973.4 6.7 88 973.9 9.2 103 974.5 15.6 115SC-51-1 977.1 980.4 1.6 12 980.6 1.8 36 980.9 2.1 67 981.0 2.2 85 981.2 2.6 141SC-52-1 979.5 979.9 15.4 11 980.1 16.3 23 980.2 16.8 39 980.2 17.1 47 980.3 17.6 64SC-53-1 965.1 968.4 8.9 155 970.0 14.1 351 971.6 22.2 586 971.7 25.3 735 972.0 33.0 999SC-56-1 980.3 982.2 6.7 16 983.2 10.8 28 984.4 15.5 41 985.0 18.1 47 986.0 23.4 68SC-57-1 989.0 989.3 0.1 59 989.8 0.2 140 991.0 0.5 248 991.7 1.0 304 992.3 1.6 457SC-58-1 1023.0 1024.1 0.0 5 1024.1 0.0 9 1024.2 0.0 18 1024.2 0.0 23 1024.3 0.0 34SC-59-1 1005.0 1006.2 0.1 42 1006.4 0.1 95 1006.6 0.1 171 1006.6 0.1 215 1006.7 0.1 324SC-66-1 1025.6 1026.1 0.0 12 1026.5 0.1 28 1027.1 0.1 51 1027.5 0.1 65 1028.1 0.1 94STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-104

PONDNAMENWL(MSL)PEAKELEV.(FT)Table 4.6.4 South Creek District: Existing Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)SC-70-1 940.0 942.4 0.3 90 943.4 0.7 196 944.6 1.5 311 945.3 2.2 374 946.0 3.1 516SC-73-1 948.0 949.4 0.2 56 951.2 0.5 125 952.9 1.4 198 953.8 2.3 239 955.8 4.2 333SC-75-1 994.8 996.5 0.0 15 998.9 0.1 34 999.7 0.2 68 999.8 0.2 85 999.9 0.2 123SC-76-1 1004.2 1004.8 0.0 12 1005.6 0.0 27 1006.6 0.1 47 1007.2 0.1 58 1008.3 0.2 85STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-105

SUBWATERSHEDNAMETable 4.6.5 South Creek District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED (FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERSC-1A 121.0 4300 Kin *** 80 28.0 68.7 0.0 72.0 98.0 0.0SC-1B 153.4 SCS 0.48 3000 1 100.0 81.9 0.8SC-2A 144.6 4200 Kin 2500 80 28.0 66.5 0.0 72.0 98.0 0.0SC-2B 160.0 SCS 0.66 1500 36 100.0 78.6 36.2SC-3A 116.5 3200 Kin 500 80 28.0 66.0 0.0 72.0 98.0 0.0SC-3B 157.4 SCS 0.49 1500 23 100.0 77.1 22.8SC-4A 136.5 4200 Kin 800 80 28.1 66.0 0.0 71.9 98.0 0.0SC-4B 57.6 SCS 0.16 2800 3 100.0 79.9 2.9SC-5 170.9 SCS 0.28 1200 7 100.0 76.7 6.8SC-6 67.5 2700 Kin 2300 80 28.0 66.0 0.0 72.0 98.0 0.0SC-7 89.9 4200 Kin 2200 80 28.0 66.0 0.0 72.0 98.0 0.0SC-8A 49.5 1900 Kin 500 80 28.0 67.3 0.0 72.0 98.0 0.0SC-8B 114.2 SCS 0.30 2700 2 100.0 77.3 2.0SC-9A 94.1 3700 Kin 400 80 28.0 66.0 0.0 72.0 98.0 0.0SC-9B 195.0 SCS 0.45 2000 2 100.0 79.5 1.8SC-10A 107.8 2900 Kin 2000 80 28.0 66.0 0.0 72.0 98.0 0.0SC-10B 530.8 SCS 1.56 200 4 100.0 73.1 4.3SC-11 142.9 4400 Kin *** 80 28.0 65.8 0.0 72.0 98.0 0.0SC-12 58.7 2500 Kin 3000 80 28.2 66.4 0.0 71.8 98.0 0.0SC-13 83.5 2100 Kin 1300 70 38.1 64.8 0.0 61.9 98.0 0.0SC-14 99.3 4200 Kin 900 80 27.9 66.0 0.0 72.1 98.0 0.0SC-15 100.3 3200 Kin 1400 80 28.6 65.9 0.0 71.4 98.0 0.0SC-16 90.6 2700 Kin 3500 60 47.6 63.9 0.0 52.4 98.0 0.0SC-17 79.7 3200 Kin 2300 33 75.8 63.1 0.0 24.2 98.0 0.0SC-18 53.0 1700 Kin 2500 57 51.1 63.9 0.0 48.9 98.0 0.0SC-19 112.3 3000 Kin 1400 56 52.7 64.2 0.0 47.3 98.0 0.0SC-20 103.6 3700 Kin 1900 46 62.4 64.4 0.0 37.6 98.0 0.0SC-21 125.5 4600 Kin 1500 70 38.7 65.4 0.0 61.3 98.0 0.0SC-22 77.2 3000 Kin 1500 80 28.0 67.1 0.0 72.0 98.0 0.0SC-23 111.2 5300 Kin 1500 80 28.0 66.1 0.0 72.0 98.0 0.0SC-24 133.3 4500 Kin 900 80 28.0 66.3 0.0 72.0 98.0 0.0SC-25 185.2 3200 Kin 3400 76 41.1 65.4 0.0 58.9 98.0 0.0SC-26 63.4 2200 Kin 2500 33 75.8 67.5 0.0 24.2 98.0 0.0SC-27 114.3 4200 Kin 3300 30 81.9 61.5 0.0 18.1 98.0 0.0SC-28 27.1 1800 Kin 2700 32 77.2 63.0 0.0 22.8 98.0 0.0SC-29 59.7 1700 Kin 3500 31 77.6 64.6 0.0 22.4 98.0 0.0SC-30 61.5 2300 Kin 2000 40 78.3 63.6 0.0 21.7 98.0 0.0SC-31A 90.4 1300 Kin *** 34 71.6 61.1 0.0 28.4 98.0 0.0SC-31B 10.3 *** 0 100.0 58.0 0.0SC-32A 59.8 3700 Kin 2000 78 30.1 66.4 0.0 69.9 98.0 0.0SC-32B 129.4 4700 Kin 100 80 28.2 65.8 0.0 71.8 98.0 0.0SC-33 106.4 2700 Kin 3000 32 77.2 64.2 0.0 22.8 98.0 0.0PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-106

SUBWATERSHEDNAMETable 4.6.5 South Creek District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED (FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERSC-34 25.1 1200 Kin 2500 33 75.6 68.4 0.0 24.4 98.0 0.0SC-35A 101.3 3300 Kin 2000 30 79.0 63.2 0.0 21.0 98.0 0.0SC-35B 12.4 1350 Kin 1200 30 79.0 63.2 0.0 21.0 98.0 0.0SC-36A 25.0 1400 Kin 600 30 79.0 63.7 0.0 21.0 98.0 0.0SC-36B 33.7 1700 Kin 800 30 79.0 63.9 0.0 21.0 98.0 0.0SC-36C 8.2 1000 Kin 1200 30 79.0 63.7 0.0 21.0 98.0 0.0SC-36D 9.3 800 Kin 800 30 79.0 63.0 0.0 21.0 98.0 0.0SC-37 184.5 4000 Kin 2800 31 78.3 63.2 0.0 21.7 98.0 0.0SC-38 136.5 2400 Kin 3300 32 77.3 63.2 0.0 22.7 98.0 0.0SC-39 41.5 1700 Kin 3800 31 77.4 63.0 0.0 22.6 98.0 0.0SC-40A 13.4 750 Kin 1300 64 45.3 64.6 0.0 54.7 98.0 0.0SC-40B 22.8 1600 Kin 1300 72 36.5 64.9 0.0 63.5 98.0 0.0SC-40C 14.8 1700 Kin 1000 69 39.7 64.8 0.0 60.3 98.0 0.0SC-40D 26.1 2100 Kin 3500 35 74.1 63.2 0.0 25.9 98.0 0.0SC-41 30.0 2300 Kin 1600 30 79.0 63.0 0.0 21.0 98.0 0.0SC-42 42.6 2200 Kin 550 56 53.2 63.9 0.0 46.8 98.0 0.0SC-43A 51.1 3300 Kin 850 31 78.4 63.0 0.0 21.6 98.0 0.0SC-43B 28.4 1200 Kin 3000 48 57.0 62.1 0.0 43.0 98.0 0.0SC-43C 62.7 1900 Kin 400 44 64.8 63.4 0.0 35.2 98.0 0.0SC-44 33.2 1900 Kin 2100 80 28.0 66.0 0.0 72.0 98.0 0.0SC-45 119.8 3400 Kin 700 31 78.0 64.0 0.0 22.0 98.0 0.0SC-46 153.7 3700 Kin 1900 39 70.0 63.3 0.0 30.0 98.0 0.0SC-47 116.4 3900 Kin 3800 18 85.7 64.3 0.0 14.3 98.0 0.0SC-48 61.0 2700 Kin 1000 47 61.7 63.5 0.0 38.3 98.0 0.0SC-49A 34.8 1900 Kin 1000 42 67.2 63.4 0.0 32.8 98.0 0.0SC-49B 57.0 2400 Kin 900 57 51.9 63.8 0.0 48.1 98.0 0.0SC-50 119.2 4200 Kin 1500 30 78.9 66.4 0.0 21.1 98.0 0.0SC-51 82.6 2100 Kin 1300 30 79.0 65.0 0.0 21.0 98.0 0.0SC-52 54.4 2300 Kin 700 71 37.1 64.5 0.0 62.9 98.0 0.0SC-53 111.8 2800 Kin 900 56 52.7 55.8 0.0 47.3 98.0 0.0SC-54 49.9 2300 Kin 1800 39 70.2 66.6 0.0 29.8 98.0 0.0SC-56 148.3 2400 Kin 500 38 65.2 64.0 0.0 34.8 98.0 0.0SC-57 85.9 3300 Kin 2300 30 78.9 66.3 0.0 21.1 98.0 0.0SC-58 19.0 1400 Kin 1500 30 79.0 64.5 0.0 21.0 98.0 0.0SC-59 129.2 3500 Kin 1900 30 79.0 67.7 0.0 21.0 98.0 0.0SC-60 74.2 2900 Kin 1900 30 79.0 64.4 0.0 21.0 98.0 0.0SC-61 34.0 1700 Kin 2300 30 79.0 65.7 0.0 21.0 98.0 0.0SC-62 40.3 2100 Kin 2300 30 79.0 66.2 0.0 21.0 98.0 0.0SC-63 26.5 2800 Kin 1400 30 78.9 66.4 0.0 21.1 98.0 0.0SC-64 45.4 2400 Kin 1400 30 79.0 67.7 0.0 21.0 98.0 0.0SC-65 63.8 2800 Kin 1300 30 79.0 67.0 0.0 21.0 98.0 0.0SC-66 46.2 2300 Kin 1100 30 79.0 65.1 0.0 21.0 98.0 0.0PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-107

SUBWATERSHEDNAMETable 4.6.5 South Creek District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED (FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERSC-67 68.4 3400 Kin 1300 30 79.0 65.1 0.0 21.0 98.0 0.0SC-68 42.8 1100 Kin 2400 30 79.0 63.0 0.0 21.0 98.0 0.0SC-69 132.2 3700 Kin *** 58 50.7 64.9 0.0 49.3 98.0 0.0SC-70 92.7 4400 Kin 2000 51 58.5 65.7 0.0 41.5 98.0 0.0SC-71 71.3 3000 Kin 500 55 55.2 66.2 0.0 44.8 98.0 0.0SC-72 37.9 1800 Kin *** 44 65.1 65.5 0.0 34.9 98.0 0.0SC-73 86.5 1600 Kin 1200 30 79.0 63.3 0.0 21.0 98.0 0.0SC-74 58.8 2200 Kin 1500 31 78.3 64.2 0.0 21.7 98.0 0.0SC-75 55.2 1700 Kin 1300 30 79.0 66.9 0.0 21.0 98.0 0.0SC-76 67.0 2700 Kin 1700 30 79.0 64.5 0.0 21.0 98.0 0.0***Runoff from this watershed drains outside the City of Lakeville.PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-108

LOCATIONDESIGNATIONTOTALDRAINAGEAREA (AC)Table 4.6.6 South Creek District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)NORTHERN CHANNEL:SC-76 67.0 1 0.29 55 1 0.51 81 1 0.80 108 1 0.97 121 1 1.32 150SC-76-1 67.0 2 day 6 2 day 10 2 day 14 2 day 16 2 day 19SC-75 55.2 1 0.31 46 1 0.55 68 1 0.87 90 1 1.04 101 1 1.42 125SC-75-1 55.2 2 day 5 2 day 9 2 day 13 2 day 15 2 day 18SC-74 58.8 1 0.30 51 1 0.52 75 1 0.81 99 1 0.97 111 1 1.33 136600 181.0 1 52 1 76 1 101 1 114 1 140SC-73 86.5 1 0.28 70 1 0.50 104 1 0.77 139 1 0.93 155 1 1.28 191SC-73-1 267.5 2 day 21 2 day 44 2 day 63 2 day 72 2 day 86SC-71 71.3 1 0.60 128 1 0.94 189 1 1.34 249 1 1.55 278 1 1.99 339SC-70 92.7 1 0.55 140 1 0.88 207 1 1.26 276 1 1.46 312 1 1.89 384SC-70-1 431.5 6 46 6 100 6 160 6 192 6 257SC-69 132.2 1 0.65 238 1 1.01 358 1 1.41 474 1 1.62 533 1 2.07 652601 563.7 1 239 1 360 1 480 1 539 1 660SC-69-1 563.7 2 day 58 2 day 118 6 182 6 217 6 368SOUTH CREEK:SC-31A 90.4 0.5 0.28 116 0.5 0.43 185 0.5 0.63 257 0.5 0.74 298 0.5 0.98 373SC-31-1 90.4 1 14 6 23 6 37 6 44 6 60SC-62 40.3 1 0.30 22 0.5 0.37 36 0.5 0.57 54 0.5 0.69 62 0.5 0.95 83SC-61 34.0 0.5 0.21 20 0.5 0.36 34 0.5 0.56 50 0.5 0.68 58 0.5 0.93 76SC-61-1 74.3 12 7 2 day 14 2 day 21 2 day 25 6 30SC-60 74.2 0.5 0.21 54 0.5 0.35 88 0.5 0.54 125 0.5 0.65 144 0.5 0.90 186609 148.5 0.5 54 0.5 88 0.5 126 0.5 145 0.5 187SC-59 129.2 0.5 0.22 106 0.5 0.38 172 0.5 0.60 241 0.5 0.72 282 0.5 0.99 353SC-59-1 277.7 1 41 6 84 6 143 6 176 6 265SC-58 19.0 0.5 0.21 13 0.5 0.35 22 0.5 0.54 32 0.5 0.65 37 0.5 0.90 48SC-58-1 19.0 0.5 2 2 day 5 6 8 6 10 6 12SC-57 85.9 0.5 0.21 79 0.5 0.37 129 0.5 0.57 181 0.5 0.69 208 0.5 0.95 260610 382.6 0.5 79 0.5 129 6 201 6 248 6 373SC-57-1 382.6 0.5 66 0.5 117 6 199 6 245 6 372SC-68 42.8 0.5 0.21 36 0.5 0.34 58 0.5 0.52 83 0.5 0.62 95 0.5 0.86 122SC-68-1 42.8 1 15 1 22 1 26 6 28 6 35SC-67 68.4 0.5 0.21 48 0.5 0.36 81 0.5 0.55 117 0.5 0.66 135 0.5 0.92 176611 111.2 0.5 59 0.5 94 0.5 133 0.5 153 0.5 196SC-66 46.2 0.5 0.21 41 0.5 0.36 65 0.5 0.55 93 0.5 0.66 105 0.5 0.92 135SC-66-1 46.2 0.5 40 0.5 63 0.5 88 0.5 98 0.5 120SC-65 63.8 0.5 0.21 59 0.5 0.37 97 0.5 0.58 138 0.5 0.71 158 0.5 0.97 197612 110.0 0.5 95 0.5 153 0.5 214 0.5 239 0.5 299SC-65-1 221.2 2 day 21 2 day 41 2 day 69 2 day 87 6 135CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-109

LOCATIONDESIGNATIONTOTALDRAINAGEAREA (AC)Table 4.6.6 South Creek District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-64 45.4 0.5 0.22 32 0.5 0.38 53 0.5 0.60 76 0.5 0.72 89 0.5 0.99 116613 266.6 0.5 32 0.5 52 2 day 85 2 day 106 6 167SC-63 26.5 0.5 0.21 26 0.5 0.37 42 0.5 0.58 59 0.5 0.69 67 0.5 0.96 84SC-54 49.9 0.5 0.30 69 0.5 0.49 111 0.5 0.73 155 0.5 0.86 176 0.5 1.15 216614 725.6 1 128 1 197 6 322 6 396 6 588SC-54-1 725.6 2 day 74 2 day 146 2 day 234 2 day 280 6 429SC-56 148.3 0.5 0.34 172 0.5 0.54 285 0.5 0.78 414 0.5 0.91 482 0.5 1.19 616SC-56-1 148.3 2 day 16 2 day 29 12 42 6 47 12 74SC-52 54.4 0.5 0.62 102 0.5 0.94 171 0.5 1.28 247 0.5 1.46 288 0.5 1.83 365SC-52-1 54.4 6 13 6 17 6 19 6 20 6 32SC-53 111.8 0.5 0.47 252 0.5 0.69 407 0.5 0.93 567 0.5 1.07 646 0.5 1.35 802615 1040.1 0.5 253 0.5 408 0.5 568 0.5 647 0.5 804SC-53-1 1040.1 2 day 108 2 day 204 12 317 12 368 12 542SC-49B 57.0 1 0.63 67 1 0.97 109 0.5 1.01 157 0.5 1.16 183 0.5 1.49 241616 1097.1 1 120 2 day 215 2 day 333 12 388 12 569SC-49-2 1097.1 2 day 113 2 day 214 2 day 330 12 386 12 547SC-51 82.6 0.5 0.21 62 0.5 0.35 103 0.5 0.55 148 0.5 0.66 170 0.5 0.91 222SC-51-1 82.6 1 35 0.5 52 0.5 70 0.5 79 1 102SC-50 119.2 0.5 0.21 92 0.5 0.37 151 0.5 0.58 216 0.5 0.69 250 0.5 0.96 320SC-50-1 201.8 2 day 23 2 day 42 6 65 6 80 6 109SC-49A 34.8 0.5 0.32 41 0.5 0.51 68 0.5 0.73 98 0.5 0.86 113 0.5 1.14 141SC-49-1 1333.7 2 day 135 2 day 261 2 day 401 12 471 12 653SC-48 74.0 1 0.50 53 1 0.80 90 1 1.15 131 1 1.34 152 1 1.74 198SC-47 116.4 0.5 0.14 69 0.5 0.25 111 0.5 0.42 156 0.5 0.52 177 0.5 0.75 226SC-47-1 116.4 2 day 9 2 day 18 2 day 28 2 day 34 2 day 41618 1524.1 2 day 150 2 day 290 2 day 448 2 day 524 12 715SC-45 119.8 0.5 0.22 103 0.5 0.36 169 0.5 0.55 238 0.5 0.66 276 0.5 0.91 341SC-46 153.7 1 0.40 117 0.5 0.47 187 0.5 0.68 274 0.5 0.80 318 0.5 1.07 411619 1797.6 3 173 2 day 340 2 day 521 2 day 612 12 810SC-46-1 1797.6 2 day 172 2 day 338 2 day 514 2 day 602 12 757SC-14 99.3 1 0.93 195 0.5 1.07 324 0.5 1.45 469 0.5 1.65 546 0.5 2.05 708SC-29 59.7 0.5 0.22 71 0.5 0.37 112 0.5 0.57 148 0.5 0.68 169 0.5 0.93 206SC-29-1 59.7 12 5 2 day 9 2 day 12 12 13 12 16SC-34 25.1 0.5 0.25 34 0.5 0.44 52 0.5 0.67 69 0.5 0.80 77 0.5 1.09 98620 84.8 0.5 34 0.5 53 0.5 70 0.5 78 0.5 100SC-33 106.4 0.5 0.23 128 0.5 0.37 196 0.5 0.57 268 0.5 0.68 300 0.5 0.93 373SC-33-1 191.2 2 day 25 6 43 6 56 6 64 6 76SC-32A 59.8 0.5 0.69 167 0.5 1.04 269 0.5 1.42 378 0.5 1.61 443 0.5 2 547SC-32-1 251.0 12 25 2 day 42 2 day 57 12 73 2 day 105SC-32B 129.4 0.5 0.71 374 0.5 1.07 589 0.5 1.44 828 0.5 1.64 971 0.5 2.04 1207SC-30 61.5 0.5 0.21 50 0.5 0.35 80 0.5 0.54 115 0.5 0.65 132 0.5 0.89 167CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-110

LOCATIONDESIGNATIONTOTALDRAINAGEAREA (AC)Table 4.6.6 South Creek District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-30-1 61.5 2 day 6 2 day 11 12 16 12 19 2 day 28SC-28 27.1 0.5 0.22 32 0.5 0.36 50 0.5 0.55 68 0.5 0.66 77 0.5 0.90 94SC-28-1 27.1 1 7 1 10 6 16 6 21 3 33SC-27 114.3 0.5 0.18 85 0.5 0.29 135 0.5 0.44 185 0.5 0.54 215 0.5 0.75 265621 202.9 0.5 85 0.5 135 0.5 185 0.5 215 0.5 265SC-27-1 202.9 2 day 19 2 day 42 2 day 65 6 78 6 120622 2 day 19 2 day 42 2 day 65 6 78 6 110623 0 0 0 0 6 9SC-26 63.4 0.5 0.25 78 0.5 0.42 122 0.5 0.65 162 0.5 0.78 185 0.5 1.05 233SC-26-1 63.4 6 8 6 14 6 22 6 26 6 36SC-25 185.2 0.5 0.58 422 0.5 0.89 682 0.5 1.22 981 0.5 1.39 1135 0.5 1.75 1429SC-25-1 451.5 2 day 40 2 day 75 2 day 120 2 day 136 2 day 151SC-24 133.3 0.5 0.71 331 0.5 1.07 537 0.5 1.45 762 0.5 1.65 889 0.5 2.05 1136SC-24-1 965.2 6 114 6 218 6 319 6 366 6 465SC-23 111.2 0.5 0.71 287 0.5 1.07 471 0.5 1.45 670 0.5 1.64 778 0.5 2.04 980624 1076.4 0.5 288 0.5 473 0.5 675 0.5 782 0.5 986SC-23-1 1076.4 0.5 247 0.5 401 0.5 577 0.5 666 0.5 850SC-22 77.2 0.5 0.71 215 0.5 1.07 353 0.5 1.46 491 0.5 1.65 578 0.5 2.06 706625 1153.6 1 360 0.5 571 0.5 813 0.5 942 0.5 1217SC-22-1 1153.6 12 135 6 255 6 383 6 455 6 597SC-21 125.5 0.5 0.61 340 0.5 0.92 542 0.5 1.26 771 0.5 1.44 854 0.5 1.80 1091SC-20 103.6 0.5 0.37 165 0.5 0.58 259 0.5 0.83 362 0.5 0.97 405 0.5 1.26 518626 1382.7 0.5 393 0.5 622 0.5 871 0.5 996 0.5 1253SC-20-1 1382.7 1 295 0.5 468 0.5 660 0.5 758 0.5 970SC-19 112.3 0.5 0.47 201 0.5 0.72 325 0.5 1 468 0.5 1.15 541 0.5 1.48 681SC-19-1 1495.0 12 176 12 323 6 501 6 598 6 801SC-18 53.0 0.5 0.48 74 0.5 0.74 126 0.5 1.03 182 0.5 1.18 214 0.5 1.51 274627 1548.0 12 181 12 333 6 516 6 617 6 828SC-18-1 1548.0 12 181 12 333 6 515 6 616 6 827SC-17 79.7 1 0.32 46 1 0.55 72 0.5 0.58 102 0.5 0.69 118 0.5 0.93 153SC-17-1 1627.7 2 day 178 12 329 12 494 12 621 6 868SC-35A 101.3 0.5 0.21 92 0.5 0.34 147 0.5 0.52 208 0.5 0.63 230 0.5 0.86 297SC-35-1 101.3 2 day 8 2 day 15 2 day 23 2 day 27 2 day 32SC-39 41.5 0.5 0.22 44 0.5 0.36 71 0.5 0.55 98 0.5 0.65 111 0.5 0.90 136SC-39-1 41.5 1 6 6 12 6 16 6 17 6 19SC-38 136.5 0.5 0.22 163 0.5 0.36 250 0.5 0.55 335 0.5 0.66 381 0.5 0.90 467SC-38-1 136.5 2 day 6 2 day 10 24 11 2 day 12 2 day 16SC-37 184.5 0.5 0.21 173 0.5 0.35 271 0.5 0.53 371 0.5 0.64 422 0.5 0.88 530628 362.5 0.5 173 0.5 271 0.5 371 0.5 422 0.5 530SC-37-1 362.5 2 day 13 2 day 28 2 day 38 2 day 41 2 day 69SC-36B 33.7 0.5 0.21 34 0.5 0.34 56 0.5 0.53 76 0.5 0.64 87 0.5 0.88 107CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-111

LOCATIONDESIGNATIONTOTALDRAINAGEAREA (AC)Table 4.6.6 South Creek District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-44 33.2 0.5 0.71 68 0.5 1.07 115 0.5 1.45 167 0.5 1.64 194 0.5 2.04 245SC-44-1 33.2 6 4 12 6 6 7 6 8 6 9SC-43C 62.7 0.5 0.35 78 0.5 0.54 129 0.5 0.78 181 0.5 0.91 210 0.5 1.19 265SC-43-2 95.9 2 day 8 2 day 12 24 15 2 day 17 2 day 22LAKE MARION 0 0 30 40 50SC-43B 28.4 0.5 0.42 35 0.5 0.65 59 0.5 0.90 86 0.5 1.04 101 0.5 1.34 128SC-43-3 28.4 2 day 4 2 day 9 6 53 6 66 6 81SC-43A 51.1 1 0.29 25 1 0.50 40 1 0.78 57 1 0.94 66 0.5 0.87 86SC-43-1 175.3 2 day 14 2 day 27 6 78 6 97 6 122631 571.5 0.5 34 2 day 56 2 day 122 2 day 144 6 177SC-36C 8.2 0.5 0.21 9 0.5 0.34 15 0.5 0.53 19 0.5 0.64 22 0.5 0.88 27SC-35B 12.4 0.5 0.21 14 0.5 0.34 22 0.5 0.52 29 0.5 0.63 33 0.5 0.86 41629 592.1 0.5 53 0.5 84 2 day 132 2 day 155 2 day 193SC-36A 25.0 0.5 0.21 25 0.5 0.34 40 0.5 0.53 55 0.5 0.64 62 0.5 0.88 77633 617.1 0.5 75 0.5 123 0.5 167 0.5 192 0.5 239SC-36D 9.3 0.5 0.21 10 0.5 0.34 15 0.5 0.52 21 0.5 0.62 24 0.5 0.86 30636 626.4 0.5 84 0.5 134 0.5 184 0.5 211 0.5 258SC-16 90.6 0.5 0.52 154 0.5 0.79 259 0.5 1.09 368 0.5 1.25 431 0.5 1.58 547SC-16-1 2445.9 2 day 226 2 day 404 12 653 12 830 6 1121SC-42 42.6 0.5 0.46 81 0.5 0.71 128 0.5 0.99 181 0.5 1.14 211 0.5 1.46 260SC-41 30.0 1 0.28 16 0.5 0.34 26 0.5 0.52 38 0.5 0.62 45 0.5 0.86 59SC-41-1 72.6 6 13 6 22 6 33 6 40 6 53SC-40A 13.4 1 0.71 18 1 1.10 30 0.5 1.14 43 0.5 1.30 50 0.5 1.65 65SC-40B 22.8 1 0.82 33 1 1.25 55 1 1.70 78 0.5 1.47 90 0.5 1.85 120SC-40C 14.8 1 0.78 21 1 1.19 34 0.5 1.24 48 0.5 1.41 56 0.5 1.77 74SC-40D 26.1 0.5 0.26 22 0.5 0.41 35 0.5 0.61 51 0.5 0.72 60 0.5 0.98 78632 149.7 1 85 1 137 1 193 1 221 1 281SC-15 100.3 1 0.92 198 0.5 1.06 325 0.5 1.44 470 0.5 1.63 536 0.5 2.03 698SC-15-1 2682.9 2 day 252 12 448 12 735 12 926 12 1251SC-13 83.5 0.5 0.61 152 0.5 0.92 254 0.5 1.26 367 0.5 1.44 425 0.5 1.81 552SC-13-1 4663.3 2 day 442 2 day 819 12 1279 12 1573 12 2041SC-12 58.7 0.5 0.71 126 0.5 1.07 209 0.5 1.45 306 0.5 1.64 355 0.5 2.04 460SC-12-1 4722.0 2 day 448 2 day 825 12 1286 12 1560 12 2072SC-11 142.9 1 0.93 213 1 1.40 355 1 1.89 513 1 2.14 599 0.5 2.04 783SC-11-1 4864.9 2 day 449 2 day 822 2 day 1272 12 1513 12 2002SOUTHERN CHANNEL:SC-10B .8 y .51 28 2 day 1.03 51 2 day 1.64 85 2 day 1.98 111 2 day 2.68 222SC-10A 107.8 0.5 0.71 329 0.5 1.07 523 0.5 1.45 736 0.5 1.64 859 0.5 2.04 1065602 638.6 0.5 329 0.5 523 0.5 736 0.5 859 0.5 1065SC-9A 94.1 0.5 0.71 269 0.5 1.07 431 0.5 1.45 606 0.5 1.64 692 0.5 2.04 879603 732.7 0.5 486 0.5 776 0.5 1098 0.5 1270 0.5 1607CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-112

LOCATIONDESIGNATIONTOTALDRAINAGEAREA (AC)Table 4.6.6 South Creek District: Proposed Conditions – Critical Events and Corresponding RunoffCRIT.EVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)SC-9B 195.0 2 day 0.71 30 12 0.63 49 6 1.03 82 6 1.25 99 6 1.71 198SC-9-1 927.7 1 101 3 150 6 208 6 239 2 day 318SC-8B 114.2 1 0.24 44 1 0.55 101 1 0.92 172 1 1.13 210 1 1.57 294604 1041.9 1 136 1 230 1 342 1 403 1 533SC-7 89.9 0.5 0.71 251 0.5 1.07 405 0.5 1.45 572 0.5 1.64 658 0.5 2.04 820SC-7-1 89.9 6 27 6 42 6 57 6 69 6 91SC-8A 49.5 0.5 0.71 136 0.5 1.07 227 0.5 1.46 321 0.5 1.65 374 0.5 2.06 467SC-8-1 49.5 6 5 3 6 6 7 12 8 12 9SC-6 67.5 0.5 0.71 187 0.5 1.07 311 0.5 1.45 437 0.5 1.64 508 0.5 2.04 633SC-6-1 206.9 12 22 2 day 38 12 54 12 62 12 107SC-5 170.9 1 0.29 78 1 0.60 168 1 0.98 278 1 1.19 339 1 1.63 469SC-4B 57.6 1 0.32 37 1 0.66 80 1 1.07 132 1 1.29 160 1 1.76 220SC-4-1 1477.3 2 day 128 2 day 230 2 day 257 2 day 268 2 day 293SC-4A 136.5 1 0.93 273 0.5 1.07 456 0.5 1.45 666 0.5 1.64 778 0.5 2.04 996SC-4-2 136.5 2 day 14 12 23 12 33 12 36 12 42SC-3A 116.5 1 0.93 214 1 1.40 347 0.5 1.45 510 0.5 1.64 598 0.5 2.04 774SC-3B 157.4 1 0.51 93 1 0.87 163 1 1.29 243 1 1.52 287 1 1.99 378605 1887.7 1 256 1 396 0.5 544 0.5 628 0.5 801SC-3-1 1887.7 2 day 180 2 day 299 6 418 6 512 6 658SC-2B 160.0 1 0.70 109 1 1.12 175 1 1.59 248 1 1.83 286 1 2.33 366SC-2A 144.6 0.5 0.71 324 0.5 1.07 540 0.5 1.45 764 0.5 1.65 898 0.5 2.05 1148606 2192.3 0.5 325 0.5 541 0.5 766 0.5 899 0.5 1150SC-2-1 2192.3 6 280 6 428 6 591 6 713 6 940SC-1B 153.4 6 0.81 69 1 0.72 139 1 1.15 222 1 1.39 267 1 1.87 361SC-1A 121.0 0.5 0.71 252 0.5 1.08 421 0.5 1.47 602 0.5 1.67 702 0.5 2.07 912607 2466.7 6 392 6 606 6 819 6 933 6 1239SC-1-1 2466.7 2 day 243 2 day 399 12 556 12 662 12 869CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRIT.EVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-113

PONDNAMENWL(MSL)PEAKELEV.(FT)Table 4.6.7 South Creek District: Proposed Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)SC-1-1 928.0 931.1 70.5 243 932.3 98.0 399 933.3 121.2 556 933.8 133.5 662 934.5 151.5 869SC-2-1 934.5 937.2 4.4 280 938.2 8.3 428 939.1 14.3 591 939.8 20.0 713 940.8 30.3 940SC-3-1 942.0 946.4 11.8 180 948.5 22.3 299 949.6 29.6 418 949.7 30.8 512 950.0 32.8 658SC-4-1 959.0 964.4 24.3 128 965.5 40.3 230 966.4 73.5 257 966.9 100.5 268 968.3 182.2 293SC-4-2 960.0 961.5 15.6 14 962.4 23.0 23 963.2 29.7 33 963.5 33.5 36 964.0 41.7 42SC-6-1 967.0 969.0 14.6 22 969.7 20.0 38 970.4 25.3 54 970.8 28.2 62 971.2 31.7 107SC-7-1 987.0 988.6 6.5 27 989.3 9.6 42 990.0 12.7 57 990.3 14.2 69 990.9 16.9 91SC-8-1 970.0 972.0 5.7 5 972.6 8.8 6 973.3 12.3 7 973.6 14.0 8 974.3 17.7 9SC-9-1 983.9 986.4 9.0 101 987.3 14.5 150 988.3 20.9 208 988.9 24.3 239 990.3 37.2 318SC-11-1 925.0 927.1 63.2 449 928.1 95.1 822 929.2 127.8 1272 929.7 143.8 1513 930.6 174.8 2002SC-12-1 930.9 934.5 15.0 448 937.0 27.1 825 939.3 38.8 1286 940.6 45.9 1560 941.8 53.1 2072SC-13-1 940.0 944.0 2.8 442 945.3 4.4 819 946.5 6.1 1279 947.2 7.1 1573 948.1 8.7 2041SC-15-1 942.0 945.4 5.7 252 946.3 8.1 448 947.1 10.7 735 947.6 12.3 926 948.8 16.6 1251SC-16-1 954.0 956.7 2.7 226 957.8 4.3 404 958.7 6.1 653 959.3 7.4 830 960.2 9.3 1121SC-17-1 962.0 966.1 21.9 178 967.6 30.8 329 969.6 42.8 494 970.1 46.4 621 970.4 48.1 868SC-18-1 975.0 977.4 1.3 181 978.3 2.1 333 979.2 3.0 515 979.6 3.5 616 980.2 4.3 827SC-19-1 982.8 984.9 21.8 176 986.0 33.8 323 986.9 42.8 501 987.3 47.7 598 988.2 58.1 801SC-20-1 998.0 1001.4 2.4 295 1002.4 3.5 468 1003.2 4.6 660 1003.5 5.1 758 1004.2 6.1 970SC-22-1 1004.0 1006.1 21.4 135 1006.9 30.6 255 1007.9 40.6 383 1008.3 45.2 455 1009.0 53.4 597SC-23-1 1013.0 1015.8 1.2 247 1016.8 1.7 401 1017.5 2.2 577 1017.9 2.5 666 1018.4 3.0 850SC-24-1 1013.3 1016.0 22.3 114 1017.0 28.6 218 1017.9 34.6 319 1018.4 37.9 366 1019.4 44.9 465SC-25-1 1045.7 1047.5 18.3 40 1048.6 29.8 75 1049.6 40.1 120 1050.3 45.7 136 1057.9 61.3 151SC-26-1 1080.9 1081.6 2.1 8 1082.1 3.6 14 1082.7 5.5 22 1083.0 6.5 26 1083.8 9.1 36SC-27-1 1092.8 1094.1 4.1 19 1094.8 6.2 42 1095.4 8.4 65 1095.8 9.7 78 1096.6 12.5 120SC-28-1 1122.0 1122.4 0.4 7 1122.6 0.6 10 1122.9 0.9 16 1123.0 1.0 21 1123.1 1.1 33SC-29-1 1116.0 1117.1 2.4 5 1117.9 4.4 9 1118.6 6.8 12 1119.0 8.1 13 1119.8 10.9 16SC-30-1 1120.0 1120.6 1.8 6 1121.1 3.4 11 1121.6 5.2 16 1121.9 6.1 19 1122.4 7.8 28SC-31-1 1106.7 1106.9 2.0 14 1107.1 3.3 23 1107.3 5.2 37 1107.4 6.3 44 1107.7 8.5 60SC-32-1 1044.0 1046.8 9.0 25 1048.2 14.5 42 1049.1 21.0 57 1049.2 21.8 73 1049.4 23.4 105SC-33-1 1086.8 1088.8 2.5 25 1090.2 4.8 43 1091.1 8.7 56 1091.6 10.9 64 1092.7 15.8 76SC-35-1 965.0 966.1 3.6 8 967.1 6.7 15 968.2 10.2 23 968.7 12.0 27 969.8 16.1 32SC-37-1 978.3 980.1 15.3 13 981.4 24.9 27 982.8 36.2 37 983.7 43.0 41 984.9 53.6 66SC-38-1 989.3 991.0 8.9 6 992.2 15.6 10 993.8 24.5 11 994.5 29.2 12 996.1 39.1 16SC-39-1 989.9 990.7 0.7 6 991.5 1.4 12 992.4 2.4 16 993.0 3.0 17 994.1 4.6 19SC-41-1 962.7 964.2 2.3 13 964.7 3.5 22 965.3 4.9 33 965.7 5.8 40 966.4 7.6 53SC-43-1 969.8 970.9 1.5 14 972.1 3.4 27 974.3 7.1 78 975.4 8.8 97 976.9 11.2 122SC-43-2 981.0 982.6 4.9 8 983.5 7.9 12 984.5 11.4 15 985.0 13.2 17 986.1 17.1 22SC-43-3 979.0 980.1 2.3 4 980.4 2.9 9 981.7 5.8 53 982.0 6.5 66 982.5 7.7 81SC-44-1 985.0 986.6 3.4 4 987.4 5.1 6 988.2 7.0 7 988.6 8.0 8 989.5 10.0 9SC-45-1 952.0 953.4 4.3 10 954.5 7.9 20 955.6 11.7 31 956.1 13.6 36 957.4 18.1 43SC-46-1 945.4 948.7 7.4 172 949.8 11.3 338 951.0 17.7 514 951.7 21.1 602 952.6 36.6 757STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-114

PONDNAMENWL(MSL)PEAKELEV.(FT)Table 4.6.7 South Creek District: Proposed Conditions – Peak Discharges and Elevations2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)SC-47-1 962.0 963.2 3.7 9 964.3 7.2 18 965.3 10.8 28 965.9 12.7 34 967.0 16.9 41SC-49-1 956.4 958.7 1.1 135 960.3 3.0 261 961.3 4.9 401 961.7 5.9 471 963.4 9.7 653SC-49-2 962.4 964.4 1.5 113 965.4 2.8 214 966.8 5.1 330 967.5 6.6 386 969.4 12.8 547SC-50-1 969.5 970.8 6.6 23 971.7 11.2 42 972.6 16.1 65 973.1 19.0 80 974.2 25.2 109SC-51-1 977.1 978.8 0.4 35 979.4 0.7 52 979.9 1.0 70 980.1 1.2 79 980.4 1.6 102SC-52-1 974.0 976.9 4.8 13 978.0 6.6 17 978.7 9.0 19 979.2 10.4 20 979.7 12.6 32SC-53-1 965.1 968.1 6.2 108 968.8 8.5 204 969.7 11.2 317 970.3 13.0 368 971.4 18.5 542SC-54-1 980.0 981.5 15.1 74 982.4 24.3 146 983.2 33.4 234 983.6 38.0 280 984.6 48.6 429SC-56-1 980.3 982.2 6.7 16 983.3 11.0 29 984.4 15.6 42 985.0 18.3 47 986.0 23.5 74SC-57-1 989.0 989.4 2.1 66 989.7 2.3 117 990.3 2.7 199 990.9 3.2 245 992.1 4.2 372SC-58-1 1023.0 1023.7 0.3 2 1024.2 0.6 5 1024.7 0.9 8 1025.0 1.1 10 1025.7 1.6 12SC-59-1 1005.0 1006.3 2.6 41 1007.2 4.7 84 1008.2 6.9 143 1008.7 8.1 176 1009.3 9.8 265SC-61-1 1050.0 1051.1 2.2 7 1052.0 4.2 14 1052.9 6.3 21 1053.4 7.4 25 1054.4 9.8 30SC-65-1 995.0 996.5 7.5 21 997.6 13.6 41 998.6 19.4 69 999.1 22.0 87 999.8 25.9 135SC-66-1 1025.6 1026.8 0.1 40 1027.4 0.1 63 1028.0 0.1 88 1028.2 0.2 98 1028.5 0.2 120SC-68-1 1051.1 1053.1 0.3 15 1053.8 0.5 22 1054.2 0.8 26 1054.6 1.1 28 1055.6 2.1 35SC-69-1 930.0 932.1 11.3 58 933.2 17.6 118 934.4 24.6 182 935.1 28.6 217 935.7 32.7 368SC-70-1 940.0 941.9 7.8 46 942.5 10.5 100 943.1 13.0 160 943.4 14.4 192 944.0 17.2 257SC-73-1 948.0 950.1 6.6 21 951.4 10.9 44 952.6 15.5 63 953.3 18.0 72 954.8 23.6 86SC-75-1 1000.0 1001.1 2.3 5 1001.9 4.1 9 1002.8 6.2 13 1003.3 7.3 15 1004.3 9.7 18SC-76-1 1008.0 1009.2 2.5 6 1010.2 4.6 10 1011.3 7.2 14 1011.8 8.5 16 1013.0 11.5 19STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-115

Table 4.7.1 Farmington Outlet District PONDNET ResultsCONDITIONAVERAGESURFACE INFLOWVOLUME(acre-feet/Year)ESTIMATEDPHOSPHORUS LOAD(Pounds/Year)AVERAGEPHOSPHORUSCONCENTRATION(ppb)PERCENT TOTALPHOSPHORUSREMOVALEXISTING CONDITIONS:FO-2 35 40 416 64FO-5 256 214 306 69FO-16 149 113 280 68FO-23 68 88 477 62FUTURE CONDITIONS WITH EXISTING WETLANDS:FO-2 176 94 197 23FO-5 1171 568 178 31FO-16 594 257 159 38FO-23 369 210 209 19FUTURE CONDITIONS:FO-2 176 59 123 52FO-5 1171 346 109 58FO-16 594 167 103 60FO-23 369 106 106 59Lakeville Water Resources Management Plan Page 4-116

Table 4.7.2 Farmington Outlet District: Existing Conditions – Hydrologic and Hydraulic ParametersSUBWATERSHEDNAMEAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAG TIME(HR)DISTANCE TODOWNSTREAMWATERSHED (FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSFO-1 34.5 SCS *** 0 100.0 68.2 0.0FO-2 134.7 SCS 0.71 *** 1 100.0 70.2 1.1FO-3 101.6 SCS 0.57 1400 1 100.0 68.2 1.2FO-4 65.8 SCS 0.64 *** 0 100.0 71.2 0.3FO-5 151.0 SCS 0.50 *** 1 100.0 72.1 0.8FO-6 259.4 SCS 0.71 3000 1 100.0 71.5 1.2FO-7 101.8 SCS 0.39 800 3 100.0 68.9 3.2FO-8 120.6 SCS 0.67 1000 0 100.0 72.6 0.0FO-9 236.4 SCS 0.40 3000 3 100.0 69.7 3.1FO-10 57.3 SCS 0.33 5400 4 100.0 69.3 3.8FO-11 189.1 SCS 0.55 1000 1 100.0 72.4 1.3FO-12 99.8 SCS 0.39 3000 3 100.0 70.3 2.5FO-13 98.0 SCS 0.33 2000 4 100.0 69.6 3.7FO-14 144.8 SCS 0.46 5400 1 100.0 68.6 1.1FO-15 116.4 SCS 0.62 1700 1 100.0 65.3 1.0FO-16 192.0 SCS 0.65 *** 1 100.0 70.0 1.4FO-17 116.5 SCS 0.61 3500 1 100.0 72.3 0.5FO-18 107.7 SCS 0.45 2400 1 100.0 67.4 0.7FO-19 82.5 SCS 0.57 300 2 100.0 70.5 2.4FO-20 142.1 SCS 0.76 3400 1 100.0 70.7 1.4FO-21 158.0 SCS 0.39 3500 3 100.0 71.7 2.8FO-22 57.2 SCS 0.32 *** 0 100.0 71.3 0.0FO-23 146.3 SCS 0.58 *** 1 100.0 72.1 0.9FO-24 73.9 SCS 0.34 3000 1 100.0 70.8 0.9FO-25 138.5 SCS 0.49 3000 1 100.0 72.2 0.6FO-26 137.3 SCS 0.48 2600 0 100.0 72.5 0.2FO-27 117.2 SCS 0.53 *** 2 100.0 71.9 1.5FO-28 31.4 SCS 0.38 *** 0 100.0 71.0 0.0***Runoff from this watershed drains outside of the City of Lakeville.PERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-117

LOCATIONDESIGNATIONTable 4.7.3 Farmington Outlet District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)FO-3 101.6 6 0.3 17 6 0.72 40 6 1.25 68 6 1.55 84 6 2.18 118FO-2 134.7 6 0.36 25 6 0.81 56 6 1.38 93 6 1.68 114 6 2.34 157FO-4 65.8 6 0.37 13 6 0.84 29 6 1.42 49 6 1.73 59 6 2.4 81FO-13 98 6 0.39 22 1 0.34 49 1 0.62 92 1 0.78 117 1 1.14 172FO-13-1 98 6 21 1 49 1 92 1 117 1 172FO-12 99.8 6 0.39 22 6 0.85 49 1 0.62 87 1 0.78 110 1 1.15 162500 197.8 6 43 6 97 1 177 1 225 1 331FO-11 189.1 6 0.43 44 6 0.93 95 6 1.52 155 6 1.85 187 1 1.24 269FO-11-1 386.9 6 87 6 178 6 312 1 387 1 594FO-10 57.3 6 0.38 12 1 0.33 28 1 0.61 53 1 0.77 67 1 1.13 100FO-10-1 444.2 6 98 6 195 6 263 6 289 6 496FO-15 116.4 2 day 0.72 17 6 0.6 37 6 1.08 66 6 1.35 83 6 1.94 118FO-14 144.8 6 0.31 26 6 0.74 61 6 1.28 104 6 1.57 128 1 1.02 191FO-14-1 261.2 2 day 42 6 93 6 155 6 183 6 234FO-9 236.4 6 0.38 50 6 0.84 113 1 0.61 199 1 0.77 253 1 1.13 373FO-9-1 236.4 6 50 6 84 6 193 1 240 1 371FO-8 120.6 6 0.41 27 6 0.91 57 6 1.5 93 6 1.83 112 6 2.52 153501 357 6 77 6 138 6 290 6 349 1 508FO-7 101.8 6 0.36 20 6 0.8 47 1 0.58 83 1 0.74 106 1 1.09 157FO-6 259.4 6 0.4 54 6 0.88 116 6 1.46 190 6 1.78 230 6 2.45 315FO-6-1 1423.6 6 270 6 516 6 786 6 990 6 1319FO-5 151 6 0.41 35 6 0.9 76 6 1.49 124 1 0.83 154 1 1.21 224502 1574.6 6 285 6 546 6 816 6 1057 6 1447FO-19 82.5 6 0.39 17 6 0.86 38 6 1.43 62 6 1.74 76 1 1.16 107FO-19-1 82.5 2 day 12 6 36 6 61 6 75 6 104FO-21 158 6 0.43 39 6 0.93 84 1 0.68 152 1 0.86 191 1 1.24 277FO-20 142.1 6 0.38 27 6 0.85 60 6 1.41 99 6 1.73 120 6 2.39 165FO-20-1 382.6 6 73 6 171 6 239 6 259 6 299FO-18 107.7 2 day 0.81 18 6 0.68 42 6 1.19 73 6 1.48 90 1 0.95 134FO-17 116.5 6 0.41 26 6 0.9 56 6 1.5 92 6 1.82 111 1 1.22 151FO-17-1 224.2 6 43 6 96 6 158 6 198 6 275FO-16 192 6 0.36 36 6 0.81 81 6 1.37 136 6 1.68 165 6 2.33 228503 798.8 6 151 6 342 6 510 6 603 6 755FO-26 137.3 6 0.41 33 6 0.91 70 1 0.66 115 1 0.84 145 1 1.22 211FO-25 138.5 6 0.41 32 6 0.9 70 6 1.49 115 1 0.83 143 1 1.21 209FO-25-1 275.8 6 65 6 140 6 228 6 274 1 348FO-24 73.9 6 0.37 16 6 0.84 37 1 0.61 68 1 0.77 87 1 1.14 129FO-24-1 73.9 6 16 6 37 1 68 1 86 1 117FO-23 146.3 6 0.41 33 6 0.9 71 6 1.49 116 6 1.81 140 1 1.21 196504 496 6 114 6 247 6 403 6 484 1 646FO-22 57.2 6 0.37 13 6 0.84 30 1 0.61 55 1 0.77 70 1 1.15 104CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-118

LOCATIONDESIGNATIONTable 4.7.3 Farmington Outlet District: Existing Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAK FLOW(CFS)FO-27 117.2 6 0.42 27 6 0.91 58 6 1.5 95 1 0.84 115 1 1.22 168FO-28 31.4 6 0.36 7 6 0.83 15 1 0.59 27 1 0.76 35 1 1.13 51CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)POND NAMENWL(MSL)Table 4.7.4 Farmington Outlet District: Existing Conditions – Peak Discharges and ElevationsPEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)FO-6-1 968.2 972.1 0.2 270 974.3 5 516 976 19 786 976.1 20.7 990 976.3 23.5 1319FO-9-1 996.3 999.5 0.1 50 1002.4 2.6 84 1003.1 3.9 193 1003.1 3.9 240 1003.2 4.2 371FO-10-1 1008.5 1013 0.2 98 1015.7 1.7 195 1018 7 263 1019 12 289 1019.9 17.3 496FO-11-1 1019.8 1022.8 0.3 87 1025.1 1.8 178 1027.1 4.6 312 1027.2 4.8 387 1027.4 5.3 594FO-13-1 1077 1080.1 0.2 21 1080.5 0.2 49 1080.6 0.3 92 1080.6 0.3 117 1080.7 0.3 172FO-14-1 1013.8 1016.4 0 42 1018.3 0.3 93 1020.2 1.4 155 1020.9 2.7 183 1022.3 6.2 234FO-17-1 982.4 984 0.1 43 986 0.2 96 987 2.2 158 987.1 2.3 198 987.3 2.6 275FO-19-1 989.6 993.3 1.4 12 993.5 0.2 36 993.7 1.9 61 993.8 2 75 994 2.2 104FO-20-1 982.2 984.5 0.1 73 987.3 0.9 171 989.6 5.3 239 990.6 9.4 259 992.7 20.4 299FO-24-1 1000 1000.7 0 16 1001.5 0.1 37 1002.7 0.2 68 1003.5 0.3 86 1004.7 0.6 117FO-25-1 985.8 988.2 0 65 990.5 0.1 140 992.2 0.4 228 993.1 0.8 274 994.9 2.8 348PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-119

SUBWATERSHEDNAMETable 4.7.5 Farmington Outlet District: Proposed Conditions – Hydrologic and Hydraulic ParametersAREA(AC)HYDRAULICLENGTH(FT)METHODUSEDLAGTIME(HR)DISTANCE TODOWNSTREAMWATERSHED(FT)COMPOSITEPERCENTIMPERVIOUSPERCENT OFWATERSHEDPERVIOUS FLOW PLANECURVENUMBERPERCENTIMPERVIOUSPERCENT OFWATERSHEDIMPERVIOUS FLOW PLANECURVENUMBERFO-1 34.5 Kin *** 20 87 62 0 13 98 0FO-2 134.7 3800 Kin *** 20 87 62 0 13 98 0FO-3 101.6 3000 Kin 1400 20 87 65 0 13 98 0FO-4 65.8 3300 Kin *** 20 87 62 0 13 98 0FO-5 151 3500 Kin *** 20 87 65 0 13 98 0FO-6 259.4 6200 Kin 3000 20 87 65 0 13 98 0FO-7 101.8 2600 Kin 800 20 87 63 0 13 98 0FO-8 120.6 4300 Kin 1000 20 87 65 0 13 98 0FO-9 236.4 2800 Kin 3000 20 87 63 0 13 98 0FO-10 57.3 2300 Kin 5400 20 87 62 0 13 98 0FO-11 189.1 3800 Kin 1000 20 87 66 0 13 98 0FO-12 99.8 2800 Kin 3000 20 87 62 0 13 98 0FO-13 98 2500 Kin 2000 20 87 68 0 13 98 0FO-14 144.8 3300 Kin 5400 20 87 62 0 13 98 0FO-15 116.4 3800 Kin 1700 20 87 62 0 13 98 0FO-16 192 4000 Kin *** 20 87 63 0 13 98 0FO-17 116.5 3400 Kin 3500 20 87 66 0 13 98 0FO-18 107.7 2800 Kin 2400 20 87 64 0 13 98 0FO-19 82.5 3400 Kin 300 20 87 63 0 13 98 0FO-20 142.1 4800 Kin 3400 20 87 63 0 13 98 0FO-21 158 2800 Kin 3500 20 87 65 0 13 98 0FO-22 57.2 2500 Kin *** 20 87 63 0 13 98 0FO-23 146.3 3900 Kin *** 20 87 65 0 13 98 0FO-24 73.9 2800 Kin 3000 20 87 63 0 13 98 0FO-25 138.5 3100 Kin 3000 20 87 65 0 13 98 0FO-26 137.3 3100 Kin 2600 20 87 65 0 13 98 0FO-27 117.2 3100 Kin *** 20 87 65 0 13 98 0FO-28 31.4 2100 Kin *** 20 87 62 0 13 98 0***Runoff from this watershed drains outside of the City of Lakeville.PERCENTIMPERVIOUSLakeville Water Resources Management Plan Page 4-120

LOCATIONDESIGNATIONTable 4.7.6 Farmington Outlet District: Proposed Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICAL EVENT(HR)FO-3 101.6 0.5 0.13 60 0.5 0.24 95 0.5 0.41 130 0.5 0.51 147 0.5 0.74 188FO-2 134.7 0.5 0.13 70 0.5 0.22 110 0.5 0.36 153 0.5 0.45 177 0.5 0.65 223FO-2-1 236.3 2 day 3 2 day 6 2 day 8 2 day 9 2 day 49FO-4 65.8 0.5 0.13 25 0.5 0.22 40 0.5 0.36 56 0.5 0.45 65 0.5 0.65 83FO-4-1 65.8 6 1 12 2 24 3 12 3 2 day 11FO-13 98 0.5 0.14 64 0.5 0.28 101 0.5 0.47 139 0.5 0.58 157 0.5 0.84 196FO-13-1 98 2 day 11 2 day 22 2 day 35 6 41 6 87FO-12 99.8 0.5 0.13 54 0.5 0.22 86 0.5 0.36 123 0.5 0.45 137 0.5 0.65 177500 197.8 0.5 55 0.5 92 0.5 123 0.5 137 0.5 172FO-11 189.1 0.5 0.13 91 0.5 0.25 146 0.5 0.43 210 0.5 0.53 242 0.5 0.77 308FO-11-1 386.9 2 day 41 2 day 87 2 day 131 6 156 6 314FO-10 57.3 0.5 0.13 33 0.5 0.22 52 0.5 0.36 72 0.5 0.45 82 0.5 0.65 103FO-10-1 444.2 2 day 40 2 day 81 2 day 123 2 day 140 2 day 174FO-15 116.4 0.5 0.13 57 0.5 0.22 94 0.5 0.36 133 0.5 0.45 154 0.5 0.65 188FO-14 144.8 0.5 0.13 82 0.5 0.22 131 0.5 0.36 181 0.5 0.45 211 0.5 0.65 266FO-14-1 261.2 2 day 21 2 day 54 2 day 86 2 day 100 6 133FO-9 236.4 0.5 0.13 129 0.5 0.22 205 0.5 0.37 293 0.5 0.47 325 0.5 0.68 423FO-9-1 236.4 2 day 16 2 day 36 2 day 56 2 day 64 2 day 99FO-8 120.6 0.5 0.13 66 0.5 0.24 103 0.5 0.41 146 0.5 0.51 169 0.5 0.74 214501 357 0.5 65 0.5 104 0.5 143 0.5 168 0.5 211FO-7 101.8 0.5 0.13 58 0.5 0.22 93 0.5 0.37 127 0.5 0.47 151 0.5 0.68 188FO-6 259.4 1 0.19 86 1 0.39 136 0.5 0.41 198 0.5 0.51 234 0.6 2.3 331FO-6-1 1423.6 2 day 72 2 day 175 2 day 291 2 day 347 2 day 441FO-5 151 1 0.19 56 0.5 0.24 91 0.5 0.41 131 0.5 0.51 156 0.5 0.74 205502 1574.6 2 day 77 2 day 187 2 day 311 2 day 372 2 day 475FO-19 82.5 0.5 0.13 42 0.5 0.22 68 0.5 0.37 97 0.5 0.47 110 0.5 0.68 140FO-19-1 82.5 2 day 10 2 day 20 6 37 6 48 6 66FO-21 158 0.5 0.13 90 0.5 0.24 146 0.5 0.41 209 0.5 0.51 237 0.5 0.74 296FO-20 142.1 0.5 0.13 81 0.5 0.22 129 0.5 0.37 178 0.5 0.47 207 0.5 0.68 257FO-20-1 382.6 2 day 35 2 day 78 2 day 126 2 day 151 6 207FO-18 107.7 0.5 0.13 61 0.5 0.23 99 0.5 0.39 135 0.5 0.49 159 0.5 0.71 198FO-17 116.5 0.5 0.13 62 0.5 0.25 99 0.5 0.43 142 0.5 0.53 164 0.5 0.77 208FO-17-1 224.2 2 day 12 2 day 25 2 day 40 2 day 51 2 day 118FO-16 192 0.5 0.13 82 0.5 0.22 133 0.5 0.37 189 0.5 0.47 219 0.5 0.68 280FO-16-1 798.8 2 day 59 2 day 135 2 day 220 2 day 269 2 day 417FO-26 137.3 0.5 0.13 74 0.5 0.24 118 0.5 0.41 168 0.5 0.51 192 0.5 0.74 244FO-25 138.5 0.5 0.13 74 0.5 0.24 118 0.5 0.41 166 0.5 0.51 189 0.5 0.74 241FO-25-1 275.8 2 day 35 2 day 76 6 131 6 163 6 221FO-24 73.9 0.5 0.13 37 0.5 0.22 61 0.5 0.37 86 0.5 0.47 101 0.5 0.68 126FO-24-1 73.9 2 day 9 2 day 18 6 30 6 37 6 48FO-23 146.3 0.5 0.13 62 0.5 0.24 101 0.5 0.41 147 0.5 0.51 167 0.5 0.74 216RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-121

LOCATIONDESIGNATIONTable 4.7.6 Farmington Outlet District: Proposed Conditions – Critical Events and Corresponding RunoffTOTALDRAINAGEAREA(AC)CRITICALEVENT(HR)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARRUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)CRITICAL EVENT(HR)FO-23-1 496 2 day 31 2 day 71 2 day 115 2 day 131 2 day 265FO-22 57.2 0.5 0.13 33 0.5 0.22 53 0.5 0.37 75 0.5 0.47 86 0.5 0.68 107FO-22-1 57.2 12 2 2 day 4 2 day 5 12 5 2 day 19FO-27 117.2 0.5 0.13 59 0.5 0.24 95 0.5 0.41 137 0.5 0.51 158 0.5 0.74 200FO-27-1 117.2 12 2 24 4 24 5 2 day 8 2 day 32FO-28 31.4 0.5 0.13 17 0.5 0.22 27 0.5 0.36 39 0.5 0.45 44 0.5 0.65 56FO-28-1 31.4 3 1 6 2 12 3 6 3 2 day 8RUNOFF(IN)PEAKFLOW(CFS)CRITICALEVENT(HR)RUNOFF(IN)PEAKFLOW(CFS)POND NAMENWL(MSL)Table 4.7.7 Farmington Outlet District: Proposed Conditions – Peak Discharges and ElevationsPEAKELEV.(FT)2-YEAR 10-YEAR 50-YEAR 100-YEAR 500-YEARSTORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)PEAKFLOW(CFS)PEAKELEV.(FT)STORAGEVOLUME(AC-FT)FO-2-1 958 959.3 15.6 3 960.4 29.9 6 961.8 46.9 8 962.5 56.2 9 963.2 66 49FO-4-1 968 969.1 3.6 1 970.2 7 2 971.5 11.4 3 972.2 13.8 3 973.2 17.4 11FO-6-1 968.2 970 39.8 72 971.4 69.1 175 972.8 100 291 973.5 114.3 347 974.9 145.8 441FO-9-1 996.3 997.7 7 16 999.1 13.3 36 1000.6 20.3 56 1001.5 24.3 64 1003 31.8 99FO-10-1 1008.5 1011.1 8.4 40 1012.7 13.7 81 1014.4 20.2 123 1015.3 23.8 140 1017.4 32.5 174FO-11-1 1019.8 1021.9 5.9 41 1023.2 10.3 87 1024.6 15.2 131 1025.5 18.5 156 1027.1 25 314FO-13-1 1076 1077.3 2.6 11 1078.3 4.8 22 1079.1 6.9 35 1079.6 7.9 41 1080.2 9.5 87FO-14-1 1013.8 1015.7 5.5 21 1017.1 9.9 54 1018.3 14.1 86 1018.9 16.4 100 1020.5 22.3 133FO-16-1 950 952.1 6.5 59 953.3 10.7 135 954.5 15 220 955.1 17 269 955.7 19.3 417FO-17-1 982.4 983.7 9.5 12 984.8 17.7 25 986 26.9 40 986.6 31.5 51 987.2 36.8 118FO-19-1 989.6 990.5 0.9 10 991.4 1.7 20 992.6 2.7 37 993.2 3.2 48 993.9 4.5 66FO-20-1 982.2 984.1 8.7 35 985.5 15.4 78 987 22.2 126 987.8 25.7 151 989.4 33.9 207FO-22-1 972 973.3 2.7 2 974.5 5.3 4 975.9 8.6 5 976.6 10.5 5 977.3 12.2 19FO-23-1 960 961.6 16 31 962.9 29.9 71 964.2 44.5 115 965 52.9 131 965.7 60.6 265FO-24-1 1000 1001.2 0.6 9 1002.3 1.3 18 1003.5 2.1 30 1004.3 2.7 37 1006.2 4.3 48FO-25-1 985.8 988.2 4.6 35 989.3 7.3 76 990.8 10.9 131 991.6 13 163 993.4 18 221FO-27-1 970 971.5 7.6 2 972.8 14.6 4 974.3 23 5 975.1 27.5 8 975.5 30.3 32FO-28-1 1014 1015.2 1.3 1 1016.3 2.6 2 1017.6 4.2 3 1018.3 5.2 3 1019.3 6.5 8PEAKFLOW(CFS)Lakeville Water Resources Management Plan Page 4-122

Crystal LakeBarr Footer: Date: 5/1/2008 5:28:28 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_2_1_Crystal_Lake_Watersheds.mxd User: arm2Kingsley LakeCL-14CL-13CL-8BCL-8ACL-1CCL-7A1CL-2CL-1ACL-22CL-21CL-24CL-7A2CL-23162ND ST WCL-3BCL-15CL-26BCL-5CL-3ACL-16CL-7CCL-26ALee LakeCL-12CL-6CL-17CL-28ACL-7BCL-29CL-4A§¨¦ CL-18CL-94567 3550 CL-11CL-4BCL-19 CL-28BCL-10CL-20KENWOOD TRAIL175TH ST WIPAVA AVECL-1BCL-25CL-27CL-30CL-31CL-32CL-33CL-34165TH ST WFigure 4.2.1CRYSTAL LAKE SUBWATERSHEDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryCrystal Lake Stormwater DistrictSubwatershed DivideProposed Subwatershed DivideText StreamsLakesData Sources: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I1,500 750 0 1,500Feet500 250 0 500Meters

Crystal LakeCL-21-1CL-31-1CL-31-2CL-33-1CL-14-1CL-8-1CL-8-2CL-7-1CL-5-1CL-3-1CL-2-1CL-15-1162ND ST WCL-16-1CL-23-1CL-25-1CL-26-1CL-30-1CL-25-2CL-27-1CL-31-3CL-32-1CL-13-1Lee LakeCL-12-1CL-3-2LakeBarr Footer: Date: 5/2/2008 10:45:04 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_2_2_Crystal_Lake_Drainage_System.mxd User: arm2Orchard LakeKingsley Lake§¨¦ 35CL-7-2CL-10-1CL-4-1CL-18-1CL-19-1CL-17-2CL-29-1Figure 4.2.2CRYSTAL LAKE STORMWATER DISTRICTDRAINAGE SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryExisting PondProposed PondStreamsLakesCrystal Lake Stormwater DistrictSubwatershed DivideProposed Subwatershed DivideData Sources: City of Lakeville, MN DNR, MnDOT.I1,250 625 0 1,250Feet500 250 0 500MetersAbandonedForcemainStorm MainPrivate Storm MainDrain TilePrivate Drain TileProposed Storm SewerProposed Sub-TrunkStorm SewerAVE

OL-30OL-29OL-28ABarr Footer: Date: 5/2/2008 8:49:24 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_3_1_Orchard_Lake_Watersheds.mxd User: arm2OL-4BOL-31OL-32OL-33OL-34OL-4AOL-6OL-7OL-27Orchard LakeOL-3OL-2OL-5OL-28BOL-26OL-1AOL-10OL-8OL-25Kingsley LakeOL-1BOL-9OL-24OL-16B162ND ST WLee Lake§¨¦ 354567 50OL-16AOL-11OL-17B1OL-17B2OL-18COL-12AOL-12BOL-18DOL-17A1OL-17A2OL-18AOL-18BKENWOOD TRAILOL-19OL-23OL-13OL-20OL-15OL-14185TH ST WOL-21OL-22IPAVA AVEFigure 4.3.1ORCHARD LAKE SUBWATERSHEDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryOrchard Lake Stormwater DistrictSubwatershed DivideProposed Subwatershed DivideStreams TextLakesData Sources: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I2,000 1,000 0 2,000Feet500 250 0 500Meters4567 9

Crystal LakeOL-28-1OL-29-1OL-28-2162ND ST WLee Lake§¨¦ 35OL-26-1OL-27-1Kingsley LakeOL-25-1OL-1-2Barr Footer: Date: 5/9/2008 11:53:44 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_3_2_Orchard_Lake_Drainage_System.mxd User: arm2Orchard LakeOL-1-1OL-2-1OL-3-2OL-3-1OL-4-1OL-5-1OL-6-1OL-7-1OL-10-1OL-8-1OL-9-1OL-24-1OL-16-1OL-16-2OL-17-4OL-11-1OL-12-1OL-18-2OL-18-4OL-18-3OL-17-1OL-18-1OL-21-1OL-19-1OL-20-1OL-23-1OL-17-2OL-17-3OL-15-1OL-13-1OL-12-2OL-14-1OL-22-1185TH ST WIPAVA AVEFigure 4.3.2ORCHARD LAKE STORMWATER DISTRICTDRAINAGE SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryExisting PondsProposed PondsStreamsLakesOrchard Lake Stormwater DistrictSubwatershed DivideI1,750 875 0 1,750Data Sources: City of Lakeville, MN DNR, MnDOT.Feet500 250 0 500MetersAbandonedForcemainStorm MainPrivate Storm MainDrain TilePrivate Drain TileProposed Storm SewerProposed Sub-TrunkStorm Sewer

ML-33Barr Footer: Date: 5/2/2008 10:11:13 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_4_1_Marion_Lake_Watersheds.mxd User: arm2ML-32ML-31ML-30ML-28ML-29 ML-25ML-26ML-27ML-23BML-23AML-19ML-20ML-21ML-18ML-10ML-22ML-8ML-9ML-124567 50ML-35ML-36AML-36BML-34ML-47ML-42ML-37185TH ST WML-41ML-38ML-43ML-46ML-39ML-40ML-45§¨¦ 35ML-44ML-1Lake Marion ML-49 ML-50ML-24AML-24CML-48ML-24BML-14ML-17ML-13ML-15ML-4 ML-2ML-11ML-3ML-7ML-5ML-6456 70215TH ST WML-51BML-51AKENWOOD TRAILSouth CreekIPAVA AVE4567 9DODD BLVDFigure 4.4.1LAKE MARION SUBWATERSHEDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundarySubwatershed DivideProposed Subwatershed DivideLake Marion Stormwater DistrictStreamsLakesSouth CreekData Sources: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I2,000 1,000 0 2,000Feet500 250 0 500 1,000MetersEast Br

Barr Footer: Date: 5/15/2008 9:08:50 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section4\Figure4_4_2_Marion_Lake_Drainage_System.mxd User: arm2ML-29-1ML-23-1ML-21-1ML-12-2ML-23-2ML-22-2ML-32-1ML-30-1ML-20-1ML-25-1ML-33-2ML-31-1ML-1-1ML-19-1ML-18-1ML-10-1ML-9-1ML-8-1ML-33-1ML-35-1ML-38-1ML-34-1ML-40-1§¨¦ 35 ML-44-14567 23ML-36-1ML-36-2ML-42-2ML-42-4ML-42-1ML-47-1ML-42-3ML-37-1185TH ST WML-43-1 ML-46-2ML-46-1ML-41-1ML-39-1ML-45-1ML-24-1ML-24-2ML-17-1ML-11-1ML-7-1ML-24-3ML-14-1ML-4-1ML-13-1456 70Lake MarionML-1-1ML-2-1215TH ST WML-3-1ML-3-3ML-49-2ML-49-1ML-45-1ML-3-2ML-50-1ML-51-14567 50IPAVA AVESouth Creek4567 9DODD BLVDFigure 4.4.2202ND ST WSouth CreekEast Branch South CreekLAKE MARION STORMWATER DISTRICTDRAINAGE SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryExisting PondsProposed PondsStreamsLakesLake Marion Stormwater DistrictSubwatershed DivideProposed Subwatershed DivideData Sources: City of Lakeville, MN DNR, MnDOT.I2,000 1,000 0 2,000 4,000Feet500 250 0 500 1,000MetersAbandonedForcemainStorm MainCEDAR AVEPrivate Storm MainDrain TilePrivate Drain TileProposed Storm SewerProposed Sub-TrunkStorm Sewer190TH ST W

Barr Footer: Date: 5/2/2008 9:02:03 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_5_1_North_Creek_Watersheds.mxd User: arm2162ND ST W165TH ST W175TH ST WNC-60NC-61NC-62185TH ST WLake MarionNC-52NC-54NC-59NC-58NC-51ENC-57NC-51HNC-51FNC-50BNC-53NC-50CND-50DNC-56NC-51JNC-51INC-51BNC-51DNC-51ANC-51CIPAVA AVENC-50A4567 9DODD BLVDNC-51GNC-55NC-38NC-45NC-37NC-42NC-44NC-46NC-41NC-43NC-47NC-49NC-40NC-48HIGHVIEW AVE202ND ST WNC-31NC-36NC-33NC-32NC-35NC-39NC-344567 23CEDAR AVE190TH ST WNC-30160TH ST WNorth CreekNC-27NC-28NC-24NC-29NC-26NC-23NC-22NC-16NC-25NC-17NC-21NC-4NC-15NC-194567 31PILOT KNOB RDNC-9ANC-20NC-14BNC-9C NC-14ANC-8NC-18NC-3NC-7Figure 4.5.1NC-9BNC-1NC-11ANC-11C NC-11BNC-10NC-13NC-6NC-12NC-5NC-2NORTH CREEK SUBWATERSHEDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryNorth Creek Stormwater DistrictSubwateshed DividesStreams TextLakesData Sources: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I3,000 1,500 0 3,000Feet500 250 0 500 1,000Meters

160TH ST WNC-31-1NC-13-1162ND ST WNC-45-1NC-9-3NC-14-1NC-14-2NC-11-1NC-51-4NC-15-1NC-11-3NC-11-2NC-51-3NC-51-2NC-44-1NC-35-14567 31NC-10-1NC-51-1NC-50-2NC-50-1NC-47-1NC-17-1NC-9-1North CreekNC-52-1NC-50-3NC-40-1NC-39-1NC-34-1NC-27-1NC-19-1NC-7-1NC-6-1NC-28-1Barr Footer: Date: 5/2/2008 11:02:58 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_5_2_North_Creek_Drainage_System.mxd User: arm2arion LakeNC-60-1NC-61-1NC-62-1NC-58-1185TH ST WIPAVA AVE4567 9NC-56-1DODD BLVD4567 23 190TH ST WCEDAR AVENC-23-1NC-21-1NC-4-1PILOT KNOB RDNC-20-1Figure 4.5.2NC-1-1NC-5-1NORTH CREEK STORMWATER DISTRICTDRAINAGE SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryExisting PondsProposed PondsStreamsLakesNorth Creek Stormwater DistrictSubwateshed DividesI2,000 1,000 0 2,000Data Sources: City of Lakeville, MN DNR, MnDOT.Feet500 250 0 500MetersAbandonedForcemainStorm MainPrivate Storm MainDrain TilePrivate Drain TileProposed Storm SewerProposed Sub-TrunkStorm Sewer

TRAIL175TH ST WIPAVA AVEFigure 4.6.1NC-24SOUTH CREEK SUBWATERSHEDSCity of LakevilleWater Resources Management PlanNC-23Barr Footer: Date: 5/2/2008 10:14:04 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_6_1_South_Creek_Watersheds.mxd User: arm2210TH ST WSC-33SC-34SC-29SC-31ASC-26SC-28SC-27SC-31B SC-30SC-10B SC-10B§¨¦ 35SC-32ASC-25456 70SC-32BSC-24SC-23SB-10B4567 50Lake MarionSC-21SC-10A185TH ST WKENWOOD TRAILSC-39SC-38SC-22SC-59SC-43BSC-20SC-37SC-9ASC-9BSC-7SC-62SC-43ASC-19SC-57SC-44SC-61SC-60SC-56SC-43CSouth CreekSC-35BSC-8ASC-8B4567 9SC-58DODD BLVDSC-52SC-63SC-42SC-41SC-36BSC-40C SC-46SC-40ASC-36ASC-36CSC-40DSC-36DSC-35ASC-18SC-6SC-68SC-67SC-64SC-54SC-53SC-49BSC-65SC-48SC-40BSC-17SC-66SC-4ASC-50SC-49ASC-16HIGHVIEW AVESC-51SC-47SC-15SC-14SC-3ASC-76North Branch of South Creek215TH ST W202ND ST WEast Branch of South CreekSC-45SC-74SC-13SC-2ASC-75SC-73SC-12SC-70SC-11SC-1ASC-5 SC-4B SC-3B SC-2B SC-1BMunicipal BoundaryParcel BoundarySouth Creek Stormwater DistrictSubwatershed DivideProposed Subwatershed DivideStreamsLakes190TH ST WData Sources: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I3,000 1,500 0 3,000CEDAR AVEFeet500 250 0 500 1,000MetersSC-71SC-69SC-72South Branch of South Creek

kOrchard LakePILOT KNOB RDBarr Footer: Date: 5/15/2008 9:10:21 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section4\Figure4_6_2_South_Creek_Drainage_System.mxd User: arm2SC-33-1SC-29-1SC-28-1SC-30-1SC-33-1SC-26-1SC-27-14567 23185TH ST WSC-61-1SC-68-1§¨¦ 35456 70215TH ST WSouth CreekIPAVA AVE190TH ST WSC-59-1SC-66-1Marion Lake4567 9SC-64-1SC-54-1SC-56-14567 50SC-51-1SC-50-1SC-75-1SC-52-1SC-76-1202ND ST WSC-43-3SC-44-1SC-49-1SC-39-1SC-47-1SC-43-2SC-37-1SC-73-1SC-38-1SC-43-1SC-41-1SC-70-1SC-36-1SC-35-1SC-69-1SC-17-1SC-33-1SC-23-1SC-32-1SC-22-1SC-24-1SC-25-1DODD BLVDNorth Branch of South CreekEast Branch of South CreekSC-12-1SC-11-1SC-19-1SC-7-1SC-6-1SC-8-1South Branch of South CreekSC-4-2SC-3-1SC-2-1SC-1-1SC-9-1SC-4-1CEDAR AVEFigure 4.6.2SOUTH CREEK STORMWATER DISTRICTDRAINAGE SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryExisting PondsProposed PondsStreamsLakesSouth Creek Stormwater DistrictSubwatershed DivideProposed Subwatershed DivideData Sources: City of Lakeville, MN DNR, MnDOT.I2,000 1,000 0 2,000 4,000Feet500 250 0 500 1,000MetersAbandonedForcemainStorm MainPrivate Storm MainDrain TilePrivate Drain TileProposed Storm SewerProposed Sub-TrunkStorm Sewer

North CreekBarr Footer: Date: 5/2/2008 9:12:16 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_7_1_Farmington_Watersheds.mxd User: arm2175TH ST WFO-13185TH ST W4567 50Lake MarionKENWOOD TRAILIPAVA AVEFO-124567 9DODD BLVDFO-11FO-10FO-14FO-9FO-8FO-6FO-15FO-18FO-21FO-26North Branch of South CreekHIGHVIEW AVE202ND ST WFO-7FO-17FO-19FO-20FO-24FO-254567 23CEDAR AVEFO-3FO-4FO-5FO-16190TH ST WFO-22FO-23FO-27FO-28FO-2FO-1Figure 4.7.1PILOT KNOB RDFARMINGTON SUBWATERSHEDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryFarmington Stormwater DistrictSubwatershed DivideStreamsLakesData Sources: City of Lakeville, Dakota County, MN DNR and MnDOT.Imagery Source: Aerials Express, 2006.I2,500 1,250 0 2,500Feet500 250 0 500 1,000MetersSou

4567 9DODD BLVDNorth CreekFO-9-1PILOT KNOB RDIPAVA AVEFO-11-1FO-10-14567 23FO-2-1FO-4-1Barr Footer: Date: 5/2/2008 11:12:48 AM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Maps\Section4\Figure4_7_2_Farmington_Drainage_System.mxd User: arm2Lake Marion4567 50 185TH ST WFO-13-1190TH ST WFO-14-1202ND ST WNorth Branch of South CreekFO-17-1CEDAR AVEFO-6-1FO-19-1FO-20-1FO-24-1FO-25-1FO-22-1FO-23-1FO-27-1FO-28-1Figure 4.7.2FARMINGTON STORMWATER DISTRICTDRAINAGE SYSTEMCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryExisting PondsProposed PondsStreamsLakesFarmington Stormwater DistrictSubwatershed DivideData Sources: City of Lakefille, MN DNR, MnDOT.I2,000 1,000 0 2,000 4,000Feet500 250 0 500 1,000MetersAbandonedForcemainStorm MainPrivate Storm MainDrain TilePrivate Drain TileProposed Storm SewerProposed Sub-TrunkStorm Sewer

Section 5.0 Programs and RegulationsThe following section provides details of the City of Lakeville’s programs and regulations thataffect water resources management within the city. It also provides a general overview of theVermillion River Watershed Joint Powers Organization’s (VRWJPO) and the Black DogWatershed Management Organization’s programs.These plans, ordinances and programs are intended as a resource for staff, residents and peopledoing business in Lakeville. They also serve here to deliver a complete guide to the Lakevillewater resources program for reviewers and others.The details presented here represent these programs as they stand as of the date of this Plan.Some of these programs will certainly change. For example, the City will be revising ordinancelanguage to conform to the VRWJPO and the BDWMO standards as part of the implementationof this plan. Users of this section should check the City’s web site athttp://www.ci.lakeville.mn.us to locate any revisions to the following programs that may haveoccurred.5.1 THE ROLE OF THE CITY OF LAKEVILLE IN WATER MANAGEMENTThe City of Lakeville actively and progressively manages stormwater to protect life, property,waterbodies within the city, and receiving waters outside the city. Toward this end the City ofLakeville has created and implements regulatory programs that accomplish these aims. The Cityintends to continue its implementation of the regulations and programs contained in thisSection.City regulations and land use controls include the following water resource-related plans andordinances: The Lakeville Stormwater Pollution Prevention Program (2007)(See Section 5.2 & Appendix C) The South Creek Management Plan (2000)(See Section 5.3) The Lakeville Wetland Management Plan (2003)(See Section 5.4) Wetland Protection (Lakeville City Code, Section 10-4-8)(See Section 5.4.1) Shoreland zoning ordinance (Lakeville City Zoning Code, Chapter 102)(See Section 5.5) Floodplain zoning requirements (Lakeville City Code, Chapter 101)Lakeville Water Resources Management Plan Page 5-1

(See Section 5.6) Grading, Drainage, and Erosion Control (Lakeville City Code, Section 10-4-5)(See Section 5.7) Storm Drainage (Lakeville City Code, Section 10-4-6)(See Section 5.8) Tree preservation ordinance (Lakeville City Code, Section 10-4-11)(See Section 5.9) Protected Areas (Lakeville City Code, Section 10-4-7)(See Section 5.10) Surface Water Management Utility (Lakeville City Code, Chapter 13)(See Section 5.11)Spill containment and cleanup plan(See Section 5.13)Wellhead Protection Plan(See Appendix E) Zoning ordinance (Lakeville City Code, Title 11). Subdivision ordinance (Lakeville City Code, Title 10).The City requires permits and/or approvals for land-disturbing projects (including developments),depending on the type of project. The following is a general list of City permits and/or approvals:Concept plan reviewWetland Conservation Act approvalPreliminary and final plat approvalRezoning approvalComprehensive Plan amendmentPlanned unit development (PUD) permitConditional use permitLand alteration (grading) permitBuilding permitApplications for preliminary plat approvals, major site plan approval, and planned unit developmentpermits must include a grading and drainage plan, an erosion control plan, a tree preservation planand a wetland plan.The City of Lakeville acts as the Local Governmental Unit for the Wetland Conservation Act. Thisincludes requiring and verifying that all projects impacting wetlands meet the requirements of theMinnesota Wetland Conservation Act and the Lakeville Wetland Management Plan.The City of Lakeville is required to meet the conditions of its NPDES MS4 permit and to implementthe Lakeville Storm Water Pollution Prevention Program. The City continues to actively engage theLakeville Water Resources Management Plan Page 5-2

MPCA and others to keep its permit and implementation up to date with regard to technology andregulations.The City also actively works with the BDWMO and the VRWJPO toward accomplishing commongoals and adhering to the policies of these watershed organizations.In order to meet permit requirements, conform to watershed standards, and improve the City’ssurface water management effectiveness, the City will review and update its existing plans andordinances to bring them in conformance with the policies and goals of this plan, the BDWMOand VRWJPO Plans, and the NPDES MS4 Permit requirements.This plan serves as the guide for the City for operating and maintaining the City’s stormwatersystem. It also lays out the general direction the City will take in planning for the future.5.2NATIONAL POLLUTION DISCHARGE ELIMINATION SYSTEM(NPDES) PROGRAMThe City of Lakeville is included in a group of communities with populations greater than 10,000that are federally required to obtain a Municipal Separate Storm Sewer System (MS4) permit formanaging non-point source storm water. The Phase II NPDES permitting process requires citiessuch as Lakeville to file a Phase II NPDES permit with the Minnesota Pollution Control Agency(MPCA), which addresses how the City will regulate and improve storm water discharges. Thepermit must include a SWPPP addressing all of the requirements of the permit.The Lakeville Environmental Resources Department has managed the permit application process,including identifying issues and developing implementation measures to address the issues. Theframework for developing the City’s NPDES Phase II permit application and plan was the City’sformer Comprehensive Surface Water Management Plan (SWMP), adopted in 1995. Lakeville’sNPDES Phase II SWPPP addresses six minimum control measures (MCMs) outlined in the permitrequirements. Many of the best management practices (BMPs) required in the NPDES permit havealready been developed and are in place. The six minimum control measures required by the permitare:1. Public outreach and education2. Public participation/involvement3. Illicit discharge detection and elimination4. Construction site runoff control5. Post-construction runoff control6. Pollution prevention/good housekeepingThe Storm Water Pollution Prevention Program (SWPPP) identifies issues related to the aboveminimum measures and more. The SWPPP is designed to address these issues, thereby minimizingLakeville Water Resources Management Plan Page 5-3

the discharge of pollutants into the city’s storm water system, protecting and enhancing waterquality, and satisfying the appropriate requirements of the Clean Water Act of 1984 and as amended.The complete SWPPP is presented in Appendix C of this plan.5.2.1 Loading Assessment and Non-Degradation ReportThe Minnesota Pollution Control Agency (MPCA) revised the General National PollutantDischarge Elimination System/State Disposal System (NPDES/SDS) Permit MNR040000(Permit) for the City of Lakeville to discharge storm water associated with Municipal SeparateStorm Sewer Systems (MS4), effective June 1, 2006. Lakeville has completed a Storm WaterPollution Prevention Program (SWPPP) to address the six minimum control measures requiredby the previous permit. The report was developed to address modifications to the SWPPP formeasures that may be necessary to meet the new, applicable requirements for the re-issuedpermit. These new requirements cover discharges to trout waters and wetlands that areapplicable to the city of Lakeville. New requirements also cover the non-degradationrequirements for selected MS4s (30 permittees including the city of Lakeville), including thedevelopment of a loading assessment and non-degradation report. The complete LakevilleLoading Assessment and Non-Degradation Report is presented in Appendix D of this plan.The report concluded that without BMPs the total average annual flow volume from the cityhas increased significantly since 1988 and would continue to increase substantially by 2020,without implementation of infiltration practices. Following implementation of BMPs theoverall average annual flow volume from the city in 2020 is 40 percent higher than the flowvolume estimate from 1988 but continued implementation of infiltration practices will offsetthe increases in flow volume between 2006 and 2020 and result in an overall flow volumereduction of more than 7 percent, compared to the volume estimate for 2006.The loading assessment and non-degradation report were completed assuming that futureBMP implementation would follow the Vermillion River Watershed Joint PowersOrganization Standards (VRWJPO, 2008 amended) for most of the city, with the exceptionof the South Creek watershed, which would continue to follow the more stringent volumecontrol requirements established in the City of Lakeville South Creek Management Plan. Asa result, the city will update its development review policies, standards and procedures, ascited in the SWPPP. In addition, the SWPPP will be modified to discuss further protectionfor the physical and biological integrity within the trout stream watersheds by implementingthe following measures:1. Establishment of buffers along stream corridors, based on the most restrictiverequirements for each type of corridor in the South Creek Management Plan and theVRWJPO Standards.2. Continued education of landowners and residents of existing developments aboutthe importance of maintaining existing stream buffers and eliminating illicit discharges.3. Establishing spill prevention and response procedures for industrial andmunicipal operations within the watersheds.Lakeville Water Resources Management Plan Page 5-4

In the few projects where the requirements of the WCA are not as comprehensive as MPCAwater quality standards, then the requirements of the NPDES permit will require an LGU tomake a determination that will also satisfy Minn. R. 7050.0186. The SWPPP will show wherethe vulnerable wellhead protection areas are within the city and define the measures that willreduce the threat to drinking water to the maximum extent practicable. These measures willbe developed in accordance with the Minnesota Department of Health’s EvaluatingProposed Storm Water Infiltration Projects in Vulnerable Wellhead Protection Areas, andthe MPCA’s Minnesota Stormwater Manual guidance for potential stormwater hotspots.The SWPPP will also provide for tracking the implementation of the BMPs and actions to betaken.5.2.2 Impaired Waters and TMDLThe federal Clean Water Act (CWA) requires states to adopt water quality standards to protectthe nation’s waters. Water quality standards designate beneficial uses for each waterbody andestablish criteria that must be met within the waterbody to maintain the water quality necessaryto support its designated use(s). Section 303(d) of the CWA requires each state to identify andestablish priority rankings for waters that do not meet the water quality standards. The list ofimpaired waters, or sometimes called the 303(d) list, is updated by the state every two years.For impaired waterbodies, the CWA requires the development of a total maximum daily load(TMDL). A TMDL is a threshold calculation of the amount of a pollutant that a waterbody canreceive and still meet water quality standards. A TMDL establishes the pollutant loadingcapacity within a waterbody and develops an allocation scheme amongst the variouscontributors, which include point sources, non-point sources and natural background, as well asa margin of safety. As a part of the allocation scheme a waste load allocation (WLA) is developedto determine allowable pollutant loadings from individual point sources (including loads fromstorm sewer networks), and a load allocation (LA) establishes allowable pollutant loadings fromnon-point sources and natural background levels in a waterbody. Table 6.1.2 lists impairedwaters within the City of Lakeville.Lake Pepin is on the impaired waters list for excess nutrients. Once the Lake Pepin TMDL iscompleted, it will impact the City of Lakeville, since the area tributary to Lake Pepin is theentire Mississippi River (and Minnesota River) basin upstream of the lake. Load reductionswill likely be assigned to the City, based on the TMDL results. The TMDL requirements willthen be incorporated into the City’s NPDES Phase II MS4 permit. This Water ResourcesManagement Plan would likely need to be amended to incorporate those TMDLrequirements.Lakeville Water Resources Management Plan Page 5-5

5.3 SOUTH CREEK MANAGEMENT PLAN1. Executive SummaryThe Lakeville South Creek Management Plan is a statement of City goals and management strategiescombined with a set of Best Management Practice recommendations for the South Creek StormwaterDistrict. The Plan is designed to preserve trout stream habitat within the city of Lakeville andminimize impact to downstream areas designated as trout stream habitat.The goals of the Lakeville South Creek Management Plan are:1. preserve trout stream habitat within the city of Lakeville2. minimize impact to downstream areas designated as trout stream habitat3. map out a coherent, long term management strategy for trout habitat preservation4. focus limited resources in the most effective direction5. create a guide for surface water design aspects of development6. identify key educational areas7. improve the quality, functionality, and biological diversity of the South Creek fishery8. continue the growth of the Airlake Industrial Park9. integrate the trout stream corridor with city green space and greenway amenities.Based on technical studies performed by Barr Engineering Company and discussions with allinterested state and local agencies the Subcommittee recommends the following protectivemeasures:1. Infiltration depressions for all new development within the South Creek Stormwater District withvolume sufficient to contain 1.5” of rainfall over the impervious surface area for all current and futurephases of the development. Infiltration depressions shall not be lined nor shall mining of nativematerial be allowed before the pond is constructed. Re-vegetation on the infiltration areas bottomsshall consist in the majority of plant types which can tolerate inundated condition for periods of daysand have root depths in excess of 18 inches.2. Site landscaping for all new developments within the South Creek Stormwater District shallinclude planting of shade trees or shrubs of native species sufficient to shade the full reach of thetrout stream channel or tributary flows adjacent to the development. It is further recommended thatspecifications provide some level of shade for infiltration areas.3. Transfer of ownership to the city of a minimum 50 foot buffer on either side of the streamcenterline in newly platted areas and where practical in existing areas.The Subcommittee recommends consideration of the following mechanisms that might be used toachieve goals outlined:Lakeville Water Resources Management Plan Page 5-6

Current controlsCity-owned bufferThe Lakeville Subdivision OrdinanceThe Lakeville Stormwater Management PlanThis Plan also outlines recommendations for a stream monitoring plan, educational project andemergency response plan.Implementation of the Plan recommendations should include ongoing evaluation of theeffectiveness of the plan measures in maintaining the cold water fishery. Adaptation of themechanisms used to protect the habitat over time should be evaluated periodically in light ofdata collected to improve the effectiveness of protective measures.2. BACKGROUND AND NEEDA branch of the Vermillion River known as South Creek runs through a large part of southern andsoutheastern Lakeville. In 1988 the Commissioner of the Minnesota Department of NaturalResources designed an area of the main branch of South Creek as trout stream within the city ofLakeville. In 1996 additional tributaries of the creek were added to the designation.The South Creek watershed within Lakeville covers approximately 5050 acres (3.9 square miles).The Airlake Industrial Park covers approximately 1300 acres within the water shed of South Creek.The watershed also includes approximately 2400 acres of residential development while another1350 acres are currently rural.The Airlake Industrial Park occupies the area of the watershed immediately adjacent to the troutdesignated stream and is generally seen as the crucial aspect of the surface water and ground watermanagement for protecting the trout fishery. Since 1995 the City’s Stormwater Management Planhas been used as the blueprint to guide stormwater design for development in the Airlake IndustrialPark. Storm ponding was designed based on NURP standards that were not developed with coldwater fisheries and temperature impacts from runoff in mind.In 1998 a joint subcommittee of the Environmental Affairs Committee and the EconomicDevelopment Commission was created to study the implications of the designation and develop aplan to manage the trout stream resource. Upon consultation with state agencies and AirlakeIndustrial Park property owners, the Subcommittee resolved to take a proactive approach tomanagement of the resource.Since then the Joint EAC/EDC South Creek Subcommittee and City staff have studied availabletechnical information and conferred with various agency technical staffers toward development ofthis Management Plan. The Subcommittee has discussed and identified a set of goals to address thediverse interests involved as follows:Lakeville Water Resources Management Plan Page 5-7

maintain or improve the trout habitatfacilitate commercial/industrial developmentcreate a guide for surface water design aspects of developmentprovide a technical basis for design criteriaintegrate the stream corridor area with the City’s greenway plans.The Subcommittee and City staff have had very productive discussions with representatives ofthe Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, DakotaCounty Soil and Water District, Metropolitan Council, Trout Unlimited, City of Farmington,Vermillion River Watershed Management Organization, and Lakeville’s storm watermanagement consultant, Barr Engineering. The result of discussions with these organizationshas been strong support for this process and some recommendations regarding protectivemeasures. Additionally, Barr Engineering has performed several important quantitative studiesto assist in evaluating potential protective measures.Protective measures are aimed at mitigating the impact of development on stormwater runoff inthe most economically efficient way possible. The major stream impacts addressed are due tourban runoff which generally increases temperature and suspended sediments, and increasesvolume and velocity.The City of Lakeville has been proactive on this issue for a number of reasons. One primaryreason is the desire for long-term economic growth and development in Airlake Industrial Park.Another factor is the continued interest of Lakeville residents in protecting unique naturalresources throughout the City. The City also recognizes that it is in a unique position to bringtogether all affected and interested parties to strive toward a mutually beneficial solution forprotecting the creek as well as continued economic growth.The South Creek Subcommittee has been striving throughout the development process toaddress concerns of property owners in the South Creek watershed. A primary goal is to allowimpervious surface percentages on parcels at the present standard while maintaining orimproving the trout habitat. In order to achieve this goal, the subcommittee is working ondeveloping creative design elements that can be incorporated with minimal infrastructureinvestment and maintenance costs. The continued development of Airlake Industrial Park hasbeen and will continue to be a focus of the subcommittee’s efforts.3. DEFINITIONSBest management practices: recommended practices toward mitigation of impacts to thecold water fishery due to urban development.Lakeville Water Resources Management Plan Page 5-8

Buffer zones: non-developed vegetated areas which extend a specified distance from theborder of the stream channel, within which no grading or altering of the natural vegetation isallowed except that required to provide for trail construction.City: the incorporated city of Lakeville.Impervious surface: areas finished with pavement, including graveled surfaces, or rooftopareas, or any surface that restricts natural percolation of rainfall to the subsurface.South Creek Stormwater District: Watershed of South Creek as defined in the LakevilleComprehensive Stormwater Management Plan.South Creek Stream Channel: The primary flow channel of streams designated as MinnesotaDepartment of Natural Resource Public Waters within the South Creek Storm Water District.4. PROTECTIVE MEASURESA. Infiltration pondingAll participants agree that the most important protective measure is the establishment of adesign specification for infiltration. This specification should replace the water quality pondingrequirement in the Lakeville Subdivision Ordinance for the South Creek Stormwater Districtonly. It would not replace the Stormwater Management Plan trunk facility requirements.The Subcommittee recommends requirement of infiltration depressions for all new developmentwithin the South Creek Stormwater District. Infiltration areas should be required to have volumesufficient to contain 1.5” of rainfall over the impervious surface area for all current and future phasesof the development, and have average depth such this volume infiltrates within 72 hours. Theinfiltration rate can be determined via direct measurement with a soil percolation test, otherpermeability test or by estimation using the conservative end of the range given in the Dakota CountySoil Survey for the soil type as mapped there. The City Engineer should have discretion to reviewand approve infiltration estimates used for infiltration area design.Areas that have very low permeability soils might require additional design considerations toenhance the rate of pond seepage such as a drain tile outlet or other measures as approved by theCity Engineer.Infiltration depressions shall not be lined nor shall mining of native material be allowed before thepond is constructed. Re-vegetation on the infiltration areas bottoms shall consist in the majority ofplant types which can tolerate inundated condition for periods of days and have root depths in excessof 18 inches. The lowest topographical point in an infiltration depression should be at least 2 feetabove the average water table in that location.Infiltration areas should armor concentrated flow areas such as outlets and restrictions againsterosion using rip-rap or other approved methods. Side slopes should have slopes equal to or lessthan 25%.Lakeville Water Resources Management Plan Page 5-9

The Technical Study commissioned to provide guidance for this Plan examined the temperatureimpact of a single infiltration pond versus its proximity to the stream. Although manyuncertainties exist in the modeling used to quantify this effect it suggested some temperatureinfluence in downstream groundwater due to concentrated infiltration ponding. Based on thiswork the Subcommittee recommends a setback distance of 75 feet from the stream centerline tothe edge of a pond. This distance is recommended by the Study as reasonable to ensure thatthermal impacts are minimal and that stream channel disturbance is minimal.In the case of distributed infiltration areas a variance to this setback should be applied where thestormwater design is such that 50% of the infiltration area volume is beyond 100 feet from thechannel centerline. In that case no setback should be required. The intent being to facilitatemitigation of potential temperature impacts by distributing infiltration areas.The above setback should not be applied to existing development or lots platted before theadoption of this plan.Infiltration areas could take the form of either infiltration ponds, swales, or a combination of thetwo, depending on the site constraints. This requirement is not substantially different from thatalready part of several developed sites in Airlake. The difference lies in the direct technicaljustification for the level, or volume, and general design of infiltration areas. Site specificinfiltration is seen as an excellent way to mitigate impacts harmful to trout from runoff such asincreased temperature and turbidity, as well as altered hydrologic characteristics.Infiltration areas will require some level of monitoring and maintenance. Monitoring should beaimed at determining whether infiltration in a pond or other area designated for infiltration isoccurring at a rate sufficient to replenish the storage volume within 72 hours or some otherdesign rate determined at the time of construction or site approval. This might be determined bysimply installing a staff gage to measure the pond depth versus time to calculate infiltration rate.Infiltration areas that no longer meet the above rate criteria should be cleaned or in some otherway enhanced to return infiltration capability.B. Planting and landscapingThe type of vegetation on a site can impact the trout habitat in at least two ways. First, certaintypes of native prairie plants extend deep roots which keep the soils permeable thus maximizinginfiltration potential. For example, native prairie grass Big Bluestem extends roots up to 10 feetbelow ground surface when fully grown. These plants could maximize pond/swale efficiency andminimize maintenance costs over time and are included in the above infiltration specification.Secondly, it has been found that plants on the stream bank which provide shade to the streamhave a significant cooling effect. Planting of trees or other shade providing plants could helpmitigate the thermal impact from impervious surface runoff.Lakeville Water Resources Management Plan Page 5-10

The Subcommittee recommends site landscaping requirements for all new developments within theSouth Creek Stormwater District that include planting of shade trees or shrubs of native speciessufficient to shade the full reach of the trout stream channel or tributary flows adjacent to thedevelopment. It is further recommended that developers provide some level of shade for infiltrationareas.C. Buffer establishmentBuffer areas are zones adjacent to a natural resource within which conservation at some level ispracticed. For example, a zone 50 feet wide might be established either side of the stream wherenatural vegetation is encouraged and impervious areas discouraged. Generally no grading,filling or alteration of vegetation through application of seed or herbicide or mowing would beallowed within buffer areas.Buffers have been shown to have dramatic impact on the ecological health of both wetlands andstreams. Buffer zones have been widely used as effective management practices toward protectingthe integrity of stream and wetland systems (Minnesota Storm Water Advisory Group, Buffer Zones,Minnesota Pollution Control Agency, September 1997). The buffers provide a margin of naturalvegetation. This margin serves a range of benefits including:a filter for trash in runoffuptake of runoff pollutantscover/nesting areas for wildlifeprotection for the intermittently flooded and sensitive outer margin of the wetland fromerosion and excessive human trafficprotection of vegetative diversity.To determine appropriate buffer widths a survey of research information and current standards atother governmental units was done. Generally, widths range from 15 feet, seen as a minimumtoward some benefit, to 100 feet, where benefit with increasing length seems to diminish.The South Creek Subcommittee recommends a minimum buffer width of 50 feet either side of theSouth Creek stream channel. This width is seen as an optimal balance between buffer effectivenessand land required. The Subcommittee recommends transfer of ownership to the city of a minimum50 foot buffer either side of the stream channel centerline for all new plats after the date of adoptionof this Plan. The City would maintain these areas to maximize the benefit the buffer provides to thestream. Specification of the buffer should not allow averaging of the width from location to location.The Subcommittee recommends that the buffer be no less than 50 feet at all locations.Delineating buffer zones in non-platted areas promises to be straight forward. In areas wheredevelopment or plats approved before adoption of this plan exist adjacent to the stream, land useand maintenance practices have become entrenched. Here buffer establishment should entailLakeville Water Resources Management Plan Page 5-11

persistent education directed toward property owners adjacent to the stream. The contributorsto this plan do not believe that it is reasonable to obtain City ownership at existing plats in mostcases. Rather, it is recommended that education resources be focused toward areas wherebuffers do not exist in accordance with the plan. It is believed that most Lakeville propertyowners will respond when the benefits are understood. Toward that end this plan recommendsan effective educational effort.5. SITES WITH EXISTING DEVELOPMENTThe Subcommittee recommends the City seek opportunities to work with existing site owners asopportunities and motivation arise to maximize opportunities to enhance infiltration on privateareas in the Airlake Industrial Park. This could take the form of education, technical assistance,and assistance in seeking funding opportunities. As redevelopment is proposed the abovestandards should be applied where feasible.The City should take the lead on City owned properties. Projects to enhance infiltration in Cityright-of-way and at the City’s Maintenance Facility in Airlake could provide excellentopportunities to improve protection of the trout stream habitat while demonstrating the viabilityof such efforts. City efforts might include improvement of road ditches in Airlake and long termmaintenance of the rural ditch type of drainage system as opposed to development of a stormsewer system. The City should also examine the feasibility of reconstructing the City’sMaintenance Facility ponding to conform to the infiltration standards outlined in Section 4.6. STREAM MONITORINGAn important aspect of this management plan is monitoring stream conditions. Thesemeasurements might be done at both small and larger scales to review the effectiveness of asingle site design and the watershed as a whole. This will allow us to determine if implementedmeasures are effective and worthwhile, and provide a basis for future management decisions.Adaptation of the mechanisms used to protect the habitat over time should be evaluatedperiodically in light of data collected to improve the effectiveness of protective measures.The Subcommittee recommends monitoring the stream for flow rate and temperature on anongoing, year round basis. At a minimum the monitoring program should examine the streamflow and temperature at the Cedar Avenue - South Creek intersection and at the upstreamboundaries of the trout designated stream at Hamburg and near Heywood Avenues. Theestablishment of a permanent comprehensive monitoring site at the intersection of CedarAvenue and South Creek which can measure temperature, flow, turbidity, and water qualityparameters is highly desirable.Monitoring should also include continued examination of flow out of Lake Marion. The overallimpact to South Creek water temperature from this flow should be studied as part of the ongoingmonitoring.Lakeville Water Resources Management Plan Page 5-12

Further, the program should examine the effectiveness of the proactive measures recommendedin this Plan. This could be done using temperature monitoring before and after construction of aproject, or upstream and downstream of an existing site to determine whether temperatureimpacts are being mitigated by the measures taken. Special attention should be given toexamining the effectiveness of infiltration ponding for mitigating temperature impacts as afunction of pond separation distance from the stream channel.7. EMERGENCY RESPONSEThe Subcommittee has examined the City’s emergency response procedures for accidentalhazardous chemical discharge. At this point in time, it does not appear that accidentaldischarges have had an impact on the stream despite some incidents. This is probably due inlarge part to the excellent state of awareness and response procedures in place for the LakevilleFire Department and links established with the Minnesota Pollution Control Agency to addressspills. However, the Subcommittee recognizes the extreme sensitivity of the resource in theAirlake Industrial Park and that the impacts of a spill could be devastating in a very short periodof time.In consultation with the Lakeville Fire Department the Subcommittee recommends thatadditional spill containment equipment be stored in the Airlake Industrial Park, preferably atthe City Maintenance Facility located there. This would provide ready access to spillcontainment equipment in Airlake beyond that carried by Fire Department vehicles on all callsin Lakeville. This recommendation acknowledges the higher potential for substancesdetrimental to the sensitive resource in the area.The Subcommittee further recommends periodic update for fire fighters regarding water qualityissues and concerns regarding the trout stream vulnerabilities with regard to chemical andtemperature contamination. This should include an initial meeting as soon as practicable toprovide fire fighters with the benefit of our current state of information.The Subcommittee also recommends periodic update for businesses in the Airlake IndustrialPark regarding water quality issues and concerns regarding the trout stream vulnerabilities withregard to chemical and temperature contamination. This should take the form of periodicinformational mailings and could include a hot line for businesses to call with concerns orquestions.Lakeville Water Resources Management Plan Page 5-13

8. EDUCATIONMeeting the goals stated will require the cooperation and proactive effort of all affected parties.In order to maintain open and effective communication, all information gathered and producedby the Subcommittee and staff will be shared with the public and property owners through avariety of communication mediums, including the Messages page in the This Week-Life & Times,Airlake Park News, and direct mailings.The Subcommittee and staff anticipate that the initial focus of educational efforts will be to assistproperty owners in understanding the recommendations. In addition to information in AirlakePark News and direct mailings, staff may also meet with property owners and/or host a tour ofthe trout stream and properties with protective measures.Over the long-term when a sampling of properties have implemented protective measures,additional educational opportunities will arise. One opportunity would be for staff to develop abrief video segment about the South Creek Trout Stream. This video segment could be shown onGovernment Channel 16, be utilized for presentations to students, and be provided to propertyowners who are considering constructing protective measures. In addition, staff may be able toutilize students, residents, and property owners on various stream management projects. Thisinvolvement of the public would increase awareness and understanding of the resource and theprotective measures in place.9. STORM TRUNK FEESThe South Creek Subcommittee recommends that the City examine the Storm Trunk Fee structure inlight of this Plan. Fees have been determined and collected based on future infrastructureassumptions as contained in the City’s 1995 Stormwater Management Plan (SWMP). Although thisPlan recommends adhering to the regional ponding plans in the SWMP it also recommendsmaintaining and enhancing the current rural drainage system in Airlake and other areas of the SouthCreek Watershed where possible. The plan also recommends land acquisition and monitoringprojects. This Plan then might alter to some degree cost assumptions with regard to storm sewercosts. These potential differences should be examined and addressed to insure equitable distributionof stormwater infrastructure costs.10. PUBLIC INPUTThe South Creek Subcommittee was formed for the purpose of reviewing available informationand providing input from range of interested groups and to provide a forum for public input ingeneral. The Subcommittee met approximately twice per month starting in October 1999. TheSubcommittee reviewed and commented on both the Barr Technical Study and development ofthis Plan. Subcommittee meetings were open to the public and were announced in localnewspapers and other mailings. State and county agencies were also notified.Recommendations and alternatives presented by the Minnesota Department of NaturalLakeville Water Resources Management Plan Page 5-14

Resources, Minnesota Board of Soil and Water Resources, Minnesota Pollution Control Agency,and the Dakota County Soil and Water Conservation District were carefully examined.This Lakeville South Creek Management Plan will be formalized and published with a commentperiod. Comments and suggestions will be reviewed and the final Plan established.11. IMPLEMENTATION AND RESPONSIBILITYResponsibility for implementing this Plan shall fall with the Environmental ResourceCoordinator under the supervision of the City Engineer. The Environmental ResourceCoordinator shall maintain the educational and monitoring programs as well as implementingthe Plan Management Strategies which are outlined herein. The Environmental ResourceCoordinator shall also periodically review the success of the plan in meeting its goals usingmonitoring or the functional assessment method outlined in this Plan.Lakeville Water Resources Management Plan Page 5-15

5.4 WETLAND MANAGEMENT PLAN (MAY 2003)Prepared by:City of Lakeville& WSB & Associates, Inc.Table of ContentsI. Executive SummaryII. IntroductionPageIII. Wetland RegulationsIV. Wetland Evaluation and Classification MethodsV. Wetland Assessment Results and Management StrategiesVI. Implementation ProgramVII. Enforcement, Amendments, and AppealsList of TablesTable 5.4 Wetland Management StrategiesList of FiguresFigure 5.4 Wetland Inventory and Classification MapSection I – Executive SummaryWetlands provide many benefits and as such are important resources to a City. Wetlandsprovide critical habitat for many types of birds, mammals, amphibians, reptiles,invertebrates, and plants. Wetlands can also act to improve water quality and provide waterquantity control by storing water during storm events. Wetlands allow for groundwaterinteractions, whether it be recharge or discharge. Additionally, wetlands provide aestheticvalue, nature observation areas, and areas for education and scientific research. Because ofthe importance of wetlands and the role wetlands play within a community, they must beconsidered during development review and city-wide planning in order to balance protectionof the wetlands and development and growth in the City.The City of Lakeville Wetland Management Plan (WMP) has been developed in conformancewith Minnesota Rules 8420.0650 and meets the requirements of the Wetland ConservationAct (WCA). This WMP has been developed with assistance from the Technical Panel, theEnvironmental Affairs Committee, and the Parks, Recreation, and Natural ResourcesCommittee. The WMP has been adopted by ordinance and is to be used in conjunction withthe City of Lakeville Stormwater Management Plan and Comprehensive Land Use Plan.Lakeville Water Resources Management Plan Page 5-16

The WMP provides a comprehensive approach for the protection and management ofwetlands within the City and allows the City to have greater control over the rules governingdecisions about these wetlands. The WMP provides greater flexibility and control overwetland management and protection, identifies regional wetland mitigation sites, andprovides management strategies for different types of wetlands.Section II contains an introduction to the WMP. It includes a description of existingresources, a discussion of the development within the City, and outlines the intent of thePlan.Section III discusses the regulatory framework for wetlands within the City. This sectionprovides details of the role of the City as the Local Government Unit (LGU) for the WCA andprovides a brief overview of other agency jurisdiction over wetlands. This section alsooutlines the wetland impact application process.Section IV contains the methods used to assess the wetland functions and values and classifythe wetlands within the City. A wetland function is defined as a physical, chemical, orbiological process or attribute of a wetland. A wetland value is the extent to which a wetlandfunction is perceived as beneficial to an individual, municipality, or other entity. A functionsand values assessment method was developed for the City by using a modified version ofMnRAM 2.0. No wetlands were delineated as part of this Plan. Absence of a wetland in theWMP does not indicate that a wetland does not exist.Section V discusses the results of the functions and values assessment and the wetlandmanagement strategies for the wetlands. Wetlands were given scores for each function thatwas evaluated. Approximately 350 wetlands within the 2020 Metropolitan Urban ServiceArea (MUSA) were evaluated as part of this Plan. Wetland Types 1-7 are represented withinthe City. The wetland management classifications include Preserve, Manage I, Manage II,Utilize, Restore, and South Creek as outlined below:Preserve (P): Wetlands that were placed into the Preserve category generally provided thehighest functions for vegetative diversity and wildlife habitat.Manage 1 (M1): Wetlands that were placed into the Manage 1 category generally providedhigh functions for vegetative diversity and wildlife habitat with some functions for waterquality protection and flood attenuation.Manage 2 (M2): Wetlands that were placed into the Manage 2 category generally providedsome functions for vegetative diversity and wildlife habitat with high functions for waterquality protection and flood attenuation.Utilize (U): Wetlands that were placed into the Utilize category generally provided thehighest functions for water quality protection and flood attenuation.Lakeville Water Resources Management Plan Page 5-17

Restore (R): Restore wetlands generally received low scores for vegetation and habitat butdue to their location, past disturbance, and/or hydrology are anticipated to be goodcandidates for restoration.South Creek: This category applies to the South Creek in the South Creek WatershedDistrict.These classifications allow the City to actively protect and manage wetlands, plan for futuredevelopment and redevelopment, and identify programs and policies for wetlandmanagement.Section VI contains an implementation program for this Plan. Section VII providesinformation on enforcement, appeals, and amendment procedures for this Plan and wetlandassessments. Section VIII contains a glossary of terms used within this Plan.A number of appendices are also included which provide supplemental information to thePlan.Section II – IntroductionThe City of Lakeville Wetland Management Plan (WMP) has been developed in conformancewith Minnesota Rules 8420.0650 and meets the requirements of the Wetland ConservationAct (WCA). This WMP has been developed with assistance from the Technical Panel,Environmental Affairs Committee and the Parks, Recreation, and Natural ResourcesCommittee. The WMP has been adopted by ordinance and is to be used in conjunction withthe City of Lakeville Stormwater Management Plan and Comprehensive Land Use Plan.The WMP was developed as part of the implementation of the Stormwater Management Planand provides a comprehensive approach for the protection and management of wetlandswithin the City. The WMP provides greater flexibility and control over wetland managementand protection, identifies regional wetland mitigation sites, and provides managementstrategies for different types of wetlands. The WMP designates wetland priorities anddefines the City’s long range goals for wetland management. The objectives of this plan areto:• Identify, classify, and create an inventory of wetlands within the City• Identify wetland functions and resources important to the City• Maintain wetland functions and values data for use by City, residents, and developers• Manage wetland resources towards improvement of their functions and values• Develop a long-term wetland management strategy• Focus limited resources in the most effective directionLakeville Water Resources Management Plan Page 5-18

• Determine the degree to which wetland avoidance must be practiced• Provide the ability to vary wetland replacement ratios• Provide technical information and baseline data regarding the functions and values ofwetlands within the City• Provide advance information for developers and the City about the quality of wetlandswithin the site.• Achieve no net loss in the quantity and quality of Lakeville’s wetlands• Provide strategies that will increase the quality of some of Lakeville’s degraded wetlands• Provide identification of wetland priorities• Provide public input into wetland management• Create a detailed GIS database about the wetlands that can be used by City Staff andresidentsA. Existing Wetland ResourcesThe City of Lakeville is located in western Dakota County. There are approximately 350wetlands within the 2020 Metropolitan Urban Services Area (MUSA) within the City limits.Wetlands and other natural resources of special interest within the City are outlined below:South Creek Trout Stream: South Creek is located in southern and southeastern Lakevilleand is tributary to the Vermillion River. A portion of the main branch of the creek and itstributaries have been designated by the DNR as a trout stream.North Creek: North Creek is a tributary to the South Creek trout stream. Implementation ofa greenway corridor is planned for the creek.Crystal Lake Golf Course Fen: The Crystal Lake Golf Course contains a calcareous fen. Thiswetland noticeably discharges groundwater and is a unique resource in the City.Marion Lake: Marion Lake is a large open water body located in the southwest quadrant ofLakeville. Marion Lake has been identified as a “priority lake” by the Metropolitan Council.Orchard Lake: Orchard Lake is located in the northwest quadrant of the City and is a uniqueresource to the City. Orchard Lake has been identified as a “priority lake” by theMetropolitan Council and the Black Dog Watershed Management Organization.Kingsley Lake: Kingsley Lake has been designated as a Natural Environment water body.Motor restrictions are in place for this water body. It is located in the northwest portion ofthe city. This lake has been identified as a “priority lake” by the Black Dog WatershedManagement Organization.Crystal Lake: Crystal Lake is a large recreation lake located in the very northern part of theCity. While most of the lake is located in Burnsville, a portion of it is within Lakeville. ThisLakeville Water Resources Management Plan Page 5-19

lake has been identified as a “priority lake” by the Black Dog Watershed ManagementOrganization.It should be noted that some of the large DNR Public Waters, such as Marion Lake andOrchard Lake, were either not evaluated or only wetland fringe areas were evaluated sincethese water bodies are under the jurisdiction of the DNR and not the Wetland ConservationAct.B. Extent of DevelopmentThe population of Lakeville has nearly doubled between 1990 and 2000, based on 2000Census data. This population increase has put pressure on the natural resources within theCity. The central portion of Lakeville has the highest concentration of development with newdevelopments proposed for residential, commercial, and industrial throughout the City.Portions of the City are outside of the 2020 MUSA boundary and in the agriculture preserveareas.In the short term, development may cause filling, dredging, and erosion and sedimentationof wetland resources. In the long term, the development can reduce or eliminate wetlandbuffers, reduce the presence of wildlife habitat, and increase stormwater runoff to waterbodies. The intent of this plan is to provide management strategies for the City in order tominimize the impact to wetlands, to continue to adequately plan for development, and tocreate an inventory of existing water resources.C. Intent of PlanThe intent of the City’s Wetland Management Plan is to provide a means for the City toprotect and manage its wetlands by utilizing the flexibility within the Wetland ConservationAct. This plan provides guidelines for wetland protection and management, assistance withthe Wetland Conservation Act, and acts as a references guide for developers to use whenworking near wetlands. The development of protection and management strategies forwetlands within the City stems from the function and values assessment completed as part ofthis Wetland Management Plan. These management strategies allow the City to protect andmanage the City’s wetland resources by implementing the flexibility in the WetlandConservation Act.Section III – Wetland RegulationsThe existing wetland regulatory framework in Minnesota involves a number of federal, state,and local agencies including the US Army Corps of Engineers, Department of NaturalResources, Watershed Districts, and the Local Government Units. This WetlandManagement Plan has been developed to be in conformance with the Wetland ConservationAct; however, a brief discussion of the role of each wetland regulatory agency is included inthis section.Lakeville Water Resources Management Plan Page 5-20

A. US Army Corps of EngineersThe US Army Corps of Engineers (COE) regulates the discharge of dredged or fill materials towetlands and other water bodies through Section 404 of the Clean Water Act provided thereis a surface water connection to navigable waters. Any impact to navigable waters orwetlands that are connected to navigable waters, including filling, draining, or excavation,may require a permit from the COE. Wetland delineations are also subject to COE approval.Depending on the size and extent of the wetland impact, the Minnesota Pollution ControlAgency may be involved in certifying the COE permit. For more information about the COEregulations, the area COE Project Manager can be contacted at (651) 290-5015 orinformation can be obtained from the COE website at www.mvp.usace.army.mil.B. Department of Natural ResourcesThe Department of Natural Resources (DNR) has jurisdiction over Public Waters andWetlands as depicted on the DNR Public Waters and Wetland maps. The DNR hasjurisdiction over Public Water and Wetlands to the Ordinary High Water (OHW) elevation orto the top-of-bank for streams. The OHW is determined by the DNR. Any impact to a PublicWater or Wetland may require a permit from the DNR. The DNR Area Hydrologist can becontacted for more information at (651) 772-7910 or information can be obtained from theDNR website at www.dnr.state.mn.us/waters/.C. Local Government Unit – Wetland Conservation ActThe Wetland Conservation Act (WCA) is a State law that first passed in 1991 and has beensubsequently amended (Minn. Laws CH 354, Minn. Statute 103G.222-2373 and otherscattered sections). The Board of Water and Soil Resources (BWSR) publishes MN Rule8420 in accordance with the Wetland Conservation Act laws. BWSR’s role is to assist theLocal Government Units (LGUs) in the implementation of WCA and to be a member of theTechnical Evaluation Panel (TEP).The intent of the WCA is to achieve a “no net loss” of wetlands in Minnesota. Therefore, theWCA prohibits filling, draining, and excavation of wetlands in some areas unless the activityis exempt or wetlands are replaced by restoration or creation of wetland of at least equalpublic value.The WCA is administered by Local Government Units (LGUs). The City of Lakeville is theLGU for the WCA within the City’s boundaries. The City can issue or deny permitsdepending on whether or not the project is in conformance with the WCA and therequirements of this Plan. The WCA exemptions are discussed in Minn. Rules 8420 and areincluded by reference to this Plan except where this Plan is more restrictive. The proceduresfor wetland impact application, sequencing, and replacement are outlined below.1. Wetland Impact and Replacement ApplicationWhen wetland filling or draining of any wetland, or excavation in the permanently andsemi-permanently flooded areas of a Type 3, 4, or 5 wetland, or excavation greater than 6Lakeville Water Resources Management Plan Page 5-21

feet in any wetland is anticipated as part of a project, an application must be completedby the project proposer and submitted to the City. If wetland impacts are unavoidable, awetland mitigation plan must be included with the application as outlined within thisPlan. An application fee may apply.2. Wetland DelineationFor any site development activities within the City, the City requires the developer tosubmit a wetland delineation report that identifies the location and extent of anywetlands present on the site. Wetland delineations are to be performed by a wetlandprofessional who has been trained in wetland delineations. Delineations will be subjectto verification by the City, the Technical Evaluation Panel (TEP), and/or the US Corps ofEngineers. It is recommended that City Staff verify wetland delineations prior to plandevelopment and/or application submittal.3. Wetland SequencingSequencing must be provided as part of an application for wetlands categorized asPreserve, Restore, Manage I, Manage II, and South Creek. The sequencing process isoutlined in Minn. Rules 8420.0520 and summarized in Table 5.4 when more restrictivethan the WCA. Sequencing for wetlands categorized as Utilize is included in LakevilleWetland Management Plan and must be referenced in the application if the developerchooses to use this sequencing discussion.4. Wetland ReplacementOnce sequencing has been completed in conformance with this Plan and it has beendetermined that wetland impacts are unavoidable, the lost functions and values of thewetland must be replaced. Replacement of lost functions and values must be inconformance with Section V.Wetland replacement should be located within the project site. If this is not feasible,replacement locations should be within the same subwatershed within the City. It isstrongly encouraged that wetlands categorized as “Restore” within this Plan are used forwetland mitigation when feasible.Wetland replacement may be completed in the form of New Wetland Credit (NWC) orthrough a combination of NWC and Public Value Credit (PVC) as provided in Section V.For a comprehensive description of NWC and PVC, see Minn. Rules 8420.0540 in theWetland Conservation Act. Storm water ponds are not eligible for NWC or PVC withinthe City.5. Replacement for Road ProjectsThrough the WCA, wetland impacts that occur due to road improvement projects thataddress safety issues and are not undertaken solely to accommodate additional trafficcapacity by the City or County as the local road authority are eligible to be replaced byLakeville Water Resources Management Plan Page 5-22

BWSR as outlined in Minn. Rules 8420.0540 Subp. 4 (5) (6) and Subp. 5. Impacts needto be avoided and minimized to the greatest extent feasible. Notification to BWSR of theintent to use BWSR mitigation is required through the application process and/or annualreporting by the City.6. City of Lakeville Wetland BankThe City of Lakeville holds a wetland bank account with BWSR. This bank can be usedfor mitigation for City projects or other projects that the City deems appropriate. TheCity will continue to actively manage this bank. Up-to-date information regarding thebalance of the bank can be obtained from BWSR.7. Wetland Replacement MonitoringThe City requires that monitoring of replacement wetlands be conducted for 5 years aftertheir establishment. A monitoring report must be submitted to the City by October 15thof each year. Monitoring requirements are outlined in the Lakeville WetlandManagement Plan. Monitoring also includes actively managing the replacement site toensure that vegetation is becoming established, erosion problem areas are stabilized,hydrology criteria are being met, and any other activities to ensure the wetlandreplacement goals are met.D. Wetland Conservation Act Application Process and Timeline (March 2008)When wetland filling or draining of any wetland, or excavation in the permanently and semipermanentlyflooded areas of a Type 3, 4, or 5 wetland, or excavation greater than 6 feet forany wetland is anticipated as part of a project, an application must be completed by theproject proposer and submitted to the City.If wetland impact is less than 10,000 sf, the City will send a summary of the project within 10days of receipt of a complete application to the TEP, the DNR, and anyone who has requestedthis type of information. If wetland impact is greater than 10,000 sf, the City will send acopy of the application and an invitation to submit comments within 10 days of receipt of theapplication to the TEP, Watershed Management Organization, the DNR, and anyone who hasrequested such information. The TEP, Watershed District, DNR and other agencies shallhave up to 30 calendar days to comment on the project.Once the comment period has ended, the City will make a decision on the application within60 days of receiving a complete application in accordance with Minn. Rules 8420.0230 Subp.2 and mail a Notice of Decision and Findings and Conclusions to all who received a summaryor copy of the permit application. The City’s decision is then effective and the project cancommence provided that replacement of the wetland impacts occurs before or concurrentlywith the wetland impact, provided all other permits from other agencies have been obtained,and the required 30-day appeal window has lapsed.Lakeville Water Resources Management Plan Page 5-23

A project proposer can appeal the City’s decision. This appeal must be made to the Board ofWater and Soil Resources within 30 days after the date on which the Notice of Decision ismailed. Minn. Rules 8420.0250 can be consulted for further information on appeals. ThisWetland Management Plan has been developed to be in conformance with the WCA. Anyfuture changes in the WCA would supersede the requirements outlined in this Plan.Section IV – Wetland Evaluation and Classification MethodsApproximately 350 wetlands were evaluated and classified within the City of Lakeville. Themethods used to accomplish these tasks are described in this section.A. Background InformationColor aerial photography of the City was obtained to provide a base map for the WetlandManagement Plan. The City’s Stormwater Management Plan (1995) had identified andprovided a limited evaluation of wetlands within the City. Additional mapping fromMetropolitan Mosquito Control District, Dakota County, and the National Wetland Inventorywere also reviewed. These sources were reviewed and compiled into one map in order todetermine the potential locations of all wetlands within the City.After potential wetland locations were identified in the office, these locations were fieldverified for their presence. The presence or absence of a wetland was determined using thecriteria for wetland delineation as set forth in the 1987 Manual for Delineating andIdentifying Jurisdictional Wetlands (US Corps of Engineers, 1987).It is important to note that wetland edges were not delineated as part of the preparation ofthis Plan. A wetland delineation will need to be conducted as part of any potential impact ordevelopment activity near the wetland. In addition, the absence of a wetland from this Plandoes not indicate that a wetland is not present on the site. Extreme efforts were taken toensure that all wetlands within the City were evaluated as part of the development of thisPlan; however, the unintentional omission of a particular wetland does not grant permissionto impact that wetland before going through the proper regulatory process.B. Wetland Function and Value AssessmentAfter background information about the location of a potential wetland was obtained and thewetland was field verified, a function and value assessment was completed for each wetlandand a photograph of the wetland was taken for reference.Functions and values of each wetland were evaluated using a method developed by the Cityof Lakeville. A wetland function is defined as a physical, chemical, or biological process orattribute of a wetland. A wetland value is the extent to which a wetland function is perceivedas beneficial to an individual, municipality, or other entity. The method was developed byCity Staff, WSB & Associates, the Technical Panel, and the Environmental Affairs Committee.The questions within the assessment were based on Minnesota Routine Assessment MethodLakeville Water Resources Management Plan Page 5-24

(MnRAM) 2.0 with changes based on the values of the City. The assessment evaluated thevalues of the following functions:• Vegetative Diversity / Integrity• Fish and Wildlife Habitat• Water Quality Protection• Flood / Stormwater Attenuation• Shoreline Protection• Groundwater Recharge & Discharge• Aesthetics, Recreation, and EducationAfter the functions and values assessment was completed for the wetlands, the wetlands wereplaced into one of six management categories based on the assessment. To place wetlandsinto management categories, the scores for each function were analyzed. This analysisstarted with identifying the wetlands that provided the strongest of the above listed functionsand which provided the weakest of the above listed functions. Scoring criteria for eachfunction was then developed.In the Lakeville MnRAM, two major sets of differing functions were identified – vegetativediversity / wildlife habitat and water quality protection / flood attenuation. Wetlands thatreceived high scores for vegetative diversity and fish / wildlife habitat generally provided ahigher quality habitat with a diverse assemblage of native plants than other wetlands that didnot score high in this area. Wetlands that received high scores for water quality protectionand flood attenuation were generally providing a significant storm water managementfunction, were often receiving direct inputs of storm water, or were identified as a regionalstorm water management area in the City’s Storm Water Management Plan. These two setsof differing wetland functions served as the basis to place wetlands into managementcategories.These two sets of criteria were analyzed for each wetland. Wetlands that scored higher thanothers for vegetative diversity and wildlife habitat were placed into management categoriesthat allowed for protection of these resources. Wetlands that scored higher than others inwater quality and flood attenuation were placed into management categories that allowed forthese wetlands to be used for storm water management.Wetlands that did not clearly function the highest for vegetative diversity / wildlife habitat orwater quality protection / flood attenuation were placed into management categories thatallowed some protection of the vegetation and wildlife with some storm water managementuses. Wetlands in this “middle” area were placed into management categories based onwhich sets of functions appeared to be more dominant based on the assessment.For wetlands that were bordering between which functions they more strongly provided,consideration was given to the future land use associated with the location of the wetland. IfLakeville Water Resources Management Plan Page 5-25

the area’s future land use was open space, parkland, or low-density development, it wasplaced into a more protective category. If the area’s future land use was high-densitydevelopment, commercial or industrial, the wetland was placed into a less protectivecategory. The aesthetic, recreation, and education function of the wetland was alsoconsidered when wetlands could not clearly be placed into a management category.A category was also developed for wetlands that showed potential to be restored. Based onfield review, these wetlands may have been impacted by agriculture or development in thepast and/or had available space for future expansion/ restoration. These wetlands wereplaced into a category that would encourage restoration through identification of these areas.It should be noted that there is occasional overlap in the scoring criteria that was developed.For these areas that there is overlap in the scoring, greater weight was given to the vegetativediversity / wildlife habitat function than the water quality / flood attenuation function toplace wetlands in management categories.The management categories and scoring criteria are described in more detail in Table 5.4.C. GIS Database for WMPInformation generated by the functions and values assessments was compiled into a GIS mapand database. This database can be used by the City, developers, and the public for planreviews, stormwater planning, and general information. This database will be updated asnecessary when new wetlands are created or wetlands are re-evaluated. The wetlandclassification map is shown as Figure 5.4.1.Section V – Wetland Assessment Results and Management StrategiesA. Wetland Inventory ResultsApproximately 350 wetlands within the City were evaluated using a modified version ofMnRAM 2.0. Wetlands were numbered based on which subwatershed they were located inand their location with approximate boundaries identified on a map.While an attempt was made to evaluate all of the wetlands within the City, access to somewetlands was unavailable. The modified MnRAM assessment will need to be undertaken atthe property owners expense if and when their land develops.B. Subwatershed Descriptions1. Crystal Lake DistrictThe Crystal Lake District is approximately 1,420 acres and is located in northernLakeville. Approximately 33 wetlands were assessed within this subwatershed.2. Orchard Lake DistrictLakeville Water Resources Management Plan Page 5-26

The Orchard Lake District is located in northwestern Lakeville and is approximately2,087 acres in size. This area is mostly developed and consists of primarily residentialareas. Approximately 110 wetlands were assessed within this subwatershed.3. Marion Lake DistrictMarion Lake District is approximately 4,791 acres in size. Approximately 103 wetlandswere assessed within this subwatershed. The wetlands in the western portion of thissubwatershed were not assessed as this area is not anticipated to develop and will remainlarge lot residential and/or undeveloped, rural areas. The remainder of thesubwatershed is more developed with medium density residential. Light industrial andcommercial areas are also located along the I-35 corridor.4. North Creek DistrictNorth Creek District is located in the northeast corner of the City and is approximately5,622 acres is size within the City limits. Approximately 54 wetlands were assessedwithin this subwatershed.5. South Creek DistrictThe South Creek District is located in the southern and central portions of the City.South Creek is designated as a trout stream. Approximately 38 wetlands were assessedwithin this subwatershed.6. Farmington Outlet DistrictThe Farmington Outlet District is located in the eastern portion of the City and isapproximately 3,410 acres in size. Approximately 7 wetlands were assessed within thissubwatershed. However, since much of this area is outside the 2020 MUSA boundaryand it not anticipated to develop, many of the wetlands in this area were not assessed.C. Wetland Management Categories and StrategiesBased on the wetland function and value assessments conducted during 2001 and 2002, sixdifferent management categories were developed as follows:Preserve (P): Wetlands that were placed into the Preserve category generally providedthe highest functions for vegetative diversity and wildlife habitat.Manage 1 (M1): Wetlands that were placed into the Manage 1 category generallyprovided high functions for vegetative diversity and wildlife habitat with some functionsfor water quality protection and flood attenuation.Manage 2 (M2): Wetlands that were placed into the Manage 2 category generallyprovided some functions for vegetative diversity and wildlife habitat with high functionsfor water quality protection and flood attenuation.Lakeville Water Resources Management Plan Page 5-27

Utilize (U): Wetlands that were placed into the Utilize category generally provided thehighest functions for water quality protection and flood attenuation.Restore (R): Restore wetlands generally received low scores for vegetation and habitatbut due to their location, past disturbance, and/or hydrology are anticipated to be goodcandidates for restoration.South Creek (SC): The South Creek category applies to the South Creek in the SouthCreek District.Each management category has a different management strategy based on the wetlandfunctions and values. These management strategies are outlined below and summarized onTable 5.4.1. Wetland buffersBuffers are an upland area adjacent to a wetland that is covered with vegetation thatexperiences little to no human impact such as mowing or fertilizing. Buffers are effectivemanagement tools for protecting wetland systems. Vegetated buffers provide cover andnesting habitat for wildlife, reduce erosion around the wetland, provide vegetative diversity,and reduce the amount of pollutants in overland overflow runoff prior to discharge to thewetland.In the past, the City has required a 17 foot buffer around wetlands in developing areas. Aspart of this Wetland Management Plan, the zoning ordinance will need to be amendedrelating to buffers around wetlands. Buffer zones around existing wetlands will be requiredfor all new development as follows:Preserve:Manage 1:Manage 2:Utilize:Restore:50 feet25 feet for wetlands less than 2 acres35 feet for wetlands larger than 2 acres17 feet for wetlands less than 2 acres25 feet for wetlands larger than 2 acres17 feet25 feetSouth Creek: 50 feet from centerline of South Creek. 17 feet for fringe wetlands thatextend past the 50-foot centerline. Buffer should be vegetated withshade species such as shrubs and trees. Buffers cannot be averaged forthese wetlands.Lakeville Water Resources Management Plan Page 5-28

Upon development, 17 feet of the required buffer will be platted as an outlot. The remainingbuffer width, if required, can be included as an outlot or included as the lot provided thathomeowners are made aware of the wetland buffer within their lot and that the buffer isdocumented as a conservation easement. Public trails or sidewalks that are a maximum of 10feet in width can be included within the buffer provided the designated buffer width ismaintained. Buffers can be averaged provided that a minimum buffer width of half of therequired buffer or 17 feet is maintained, whichever is greater. For wetlands that are withinthe City’s property, the City anticipates implementing and maintaining these buffers;however, these buffers will not be platted separately.A 25-foot buffer is also required around newly created wetland mitigation sites. As outlinedwithin the Minnesota Rules 8420.0541, Subp. 6, this 25-foot buffer can be used for PublicValue Credit.2. Stormwater managementWetlands have the ability to provide stormwater treatment and decrease the risks ofdownstream flooding. The nutrients and sediment present in stormwater runoff can have adetrimental impact on some wetlands. However, other wetlands are not as sensitive tostormwater impacts and may provide an overall benefit to the community by providingstormwater treatment functions. To address stormwater management, the following wetlandmanagement strategies have been developed as part of this Plan:Preserve:Manage 1:Manage 2:Utilize:Restore:Pretreatment of sediment and nutrients will be required. The existing bouncefrom a 2-year storm event will be maintained, if feasible. The existing two-yearhigh water level is outlined in the Stormwater Management Plan.Pretreatment of sediment and nutrients will be required. The bounce within thewetland will be limited to the existing level plus 0.5 feet for a 2-year stormevent, if feasible. The existing two-year high water level is outlined in theStormwater Management Plan.Pretreatment of sediment and nutrients will be required. The bounce within thewetland will be limited to the existing level plus 1 foot for a 2-year storm event,if feasible. The existing two-year high water level is outlined in the StormwaterManagement Plan.These wetlands can be used for stormwater management and treatment. Thereis no requirement on the bounce within these wetlands.Pretreatment of sediment and nutrients will be required. The bounce within thewetland will be limited to the existing level plus 1 foot for a 2-year storm event,Lakeville Water Resources Management Plan Page 5-29

if feasible. The existing two-year high water level is outlined in the StormwaterManagement Plan.South Creek: Pretreatment of nutrients and sediment will be required. Infiltration shall beprovided prior to discharge to the South Creek for 1.5” of rainfall over theimpervious area within 72 hours as per the South Creek Management Plan.Consultation of the South Creek Management Plan is necessary to determineadditional design requirements.3. Wetland mitigation and sequencing (March 2008)The Wetland Conservation Act (WCA) guidelines serve as a baseline for the evaluation ofimpacts and associated wetland mitigation and replacement plan. The Wetland ManagementPlan outlines guidelines for City Staff, Planning Commission, the Parks, Recreation andNatural Resource Committee, and ultimately, the City Council to use during review ofprojects impacting wetlands in each management category to ensure the protection ofwetlands and conformance with State rules.Preserve:Wetlands in this category shall receive the maximum amount of protection underthis Plan. Avoidance is strongly recommended and impacts will be allowed onlyunder extreme hardship. Filling of edges of these wetlands to accommodatedevelopment, such as building pads, driveways, or parking lots etc. is not allowed.Replacement of the wetland’s functions and values will be required at a 3:1 ratiowith a minimum of 1.5 acres of new wetland credit (NWC) and maximum of 1.5acres Public Value Credit (PVC). Sequencing is required as per Minnesota Rules8420.0520 and the management strategy outlined for this category.Manage 1: Mitigation of wetlands in this category will be at a 2:1 ratio with 1 acre of NWCminimum and 1 acre of PVC maximum for every acre impacted. Sequencing isrequired as per Minnesota Rules 8420.0520.Manage 2: Mitigation of wetlands in this category will be at a 2:1 ratio with 1 acre of NWCminimum and 1 acre of PVC maximum for every acre impacted.A wetland mitigation fee in-lieu of direct replacement criteria may also be usedfor mitigation. The City will determine if this option is appropriate on a site-bysitebasis. The amount of this fee will be determined by the City. The fee will beused by the City to provide mitigation for these impacted wetlands within 5 yearsof the project. The City will review its overall achieved wetland mitigation ratioevery 5 years to ensure a 2:1 ratio of wetland mitigation is met. Sequencing isrequired as per Minnesota Rules 8420.0520.The City will work to provide incentives to developers who improve the functionsand values of Manage 2 wetlands.Lakeville Water Resources Management Plan Page 5-30

Utilize:Mitigation of wetlands in this category can be at a 1:1 ratio with 0.5 acre of NWCminimum and 0.5 acre of PVC maximum for every acre impacted. A wetlandmitigation fee in-lieu of direct replacement may also be used for mitigation ofthese wetlands. The City will determine if this option is appropriate on a site-bysitebasis. The amount of this fee will be determined by the City. The fee will beused by the City to provide mitigation for these impacted wetlands within 5 yearsof the project. The City will review its overall achieved wetland mitigation ratioevery 5 years to ensure a 2:1 ratio of wetland mitigation is met. The City mayrequire 2:1 replacement if a City mitigation project has not been identified.Restore:Mitigation of wetlands in this category will be at a 2:1 ratio with 1 acre of NWCminimum and 1 acre of PVC maximum for every acre impacted. Sequencing isrequired as per Minnesota Rules 8420.0520.To promote the restoration of these wetlands, the City will provide incentives todevelopers to restore these wetlands or undertake restoration as a City project asfeasible.South Creek: Impacts to the Creek will be allowed only under extreme hardship.Mitigation will be required at a 2:1 ratio. Sequencing is required as perMinnesota Rules 8420.0520.Actions eligible for wetland mitigation are outlined with Minnesota Rules8420.0541. However, the City does not accept water quality ponds as wetlandmitigation.4. New wetlands and wetlands not assessedNew wetlands include wetlands created as part of a wetland mitigation/creation project thatdid not exist at the time this plan was adopted. Wetland areas not intentionally created suchas those created by culvert blockage, beavers, etc. as outlined in Minn. Rules 8420.0122 shallnot become part of this plan. City Staff will initially place newly created wetlands in themanagement category of the wetland that is being replaced or as otherwise determined byStaff. Newly created wetlands for mitigation are required to have a 25-foot buffer.City Staff will review the newly created wetlands 2.5 years and 5 years aftercreation/restoration to determine if the wetland meets the functions and values of themanagement category of the wetland that it replaced. The annual wetland monitoringreports as required by the Wetland Conservation Act will also be used in this evaluation. TheCity will determine if additional work is needed or if the management goal has been met or isattainable in the near future.Lakeville Water Resources Management Plan Page 5-31

All known wetlands within the study area were evaluated with the exception of those areaswhere permission to access the site was not granted or the site could not be accessed due tosafety issues. The absence of a wetland from this plan does not mean that a wetland is notpresent on the site. Extreme efforts were taken to ensure that all wetlands within the studysite were evaluated as part of the development of this plan; however, the unintentionalomission of a particular wetland does not grant permission to impact that wetland beforegoing through the proper regulatory process. It is important to note that wetland edges werenot delineated as part of this project. A wetland delineation will need to be performed aspart of any potential impact of development activity near the wetlands.If an existing wetland was not evaluated as part of this plan, the assessment contained withinthe Wetland Management Plan will need to be completed by the applicant and submitted tothe City for review and classification.For any wetlands that the City was not permitted to access or were inadvertently omitted, anassessment will need to be undertaken by the property owner if and when their landdevelops. The assessment will be required to be conducted by a trained wetlandprofessional. Based on this assessment, the City Staff will place the wetland into amanagement category.5. Wetlands within the 2020 MUSA and Agricultural Preserve DistrictWetlands within the 2020 MUSA and the Agricultural Preserve District were not evaluatedas part of this Plan. However, if land development activities occur within these areas, theCity will require that the functions and values of the wetlands within the development areabe evaluated. Development within these areas will then be required to meet therequirements of this Plan.Table 5.4 summarizes the wetland management strategies for each management category.Section VI – Implementation ProgramAs part of this Wetland Management Plan, several programs and projects have beenidentified to protect wetlands as the City continues to experience development pressure. Thefollowing lists programs and/or projects that have been identified by this Plan.A. Administer and enforce erosion and sediment control policies.The City shall continue to enforce its erosion and sedimentation control ordinance.B. Adopt wetland buffer requirements.The wetland buffer requirements outline in Section V of this Plan shall be formally adoptedby the City through zoning ordinance. The purpose of these buffers are to protect wetlands,provide habitat for wildlife, and provide water quality protections.Lakeville Water Resources Management Plan Page 5-32

C. Undertake wetland restoration within the City.As part of this Plan, some wetlands were placed into the Restore category. As fundingbecomes available, the City shall implement restoration projects for these wetlands.D. Maintain wetland banking account with BWSR.The City currently has a wetland bank account with BWSR. The City shall maintain thisaccount and deposit additional wetland credits as they become available.E. Public education program.As part of the public education program, the City shall continue to educate its residents, CityStaff, and business owners on the importance of wetlands, wetland buffers, and goodwatershed stewardship. This can include articles in the City’s newsletter, information on theCity’s web-page, and implementation of an Adopt-A-Wetland programF. Investigate and implement biological control program for purple loosestrife.The City shall investigate the feasibility of implementing a purple loosestrife control programthrough the DNR’s biological control program.G. Evaluate mitigation ratios.The City will annually track the amount of wetland impacted and mitigated. The City willprovide mitigation at least every 5 years to maintain a “no net loss” and 2:1 mitigation ratioin conformance with the WCA and this Plan.H. Implement Wetland Management Plan.The City will adopt the Plan and its associated regulations by ordinance and continue toadminister the WCA as outlined within this Plan.Section VII – Enforcement, amendments, and appealsIt is the intention of the City to have this Wetland Management Plan reviewed and approvedby the Board of Water and Soil Resources (BWSR) and adopted through ordinance by theCity. Once approved, no significant changes to this Plan can be made without the approval ofBWSR. Significant changes to this Plan shall be made known to the following parties:The Mayor, City Council, and City StaffPlanning CommissionCity of Lakeville Parks, Recreation, and Natural Resources CommitteeBoard of Water and Soil ResourcesDakota Soil and Water Conservation DistrictMinor changes to the Plan including the addition of newly classified wetlands can be made bythe City Engineer without outside review. Revision to the management strategies shall beconsidered a major change.Lakeville Water Resources Management Plan Page 5-33

The management classification of a wetland(s) within the Plan can be appealed by thelandowner, project proposer, or other interested party. This appeal must be submitted inwriting to the City and include documentation supporting the reasons for placing a wetlandinto a different management category. This written appeal must be submitted to the CityEngineer prior to or along with the wetland impact permit application. A fee, as set by theCity, will be required for each wetland being appealed. The appeal will be reviewed by CityStaff and the Technical Evaluation Panel. A decision will be made regarding the appealwithin 60 days of receipt of the appropriate documentation from the appellant if the appealis submitted during the growing season. If the appeal is submitted outside of the growingseason, a decision will be made within 60 days after the start of the growing season. Theappellant will be notified in writing of the panel’s decision.The City’s decision regarding the wetland impact permit application can be appealed by aproject proposer. This appeal must be made to BWSR within 30 days after the date on whichthe decision of the City is mailed to those required to receive notification of the decision.Minn. Rules 8420.0250 can be consulted for further information.Lakeville Water Resources Management Plan Page 5-34

Table 5.4 Wetland Management StrategiesClassificationPreserveManage IManage IIGeneral Scoring/Percentage aVegetation: All or ¾ ofpointsWildlife: >40%Vegetation: ½ to ¾ ofpoints.Wildlife: 20-40%Water Quality: 0-70%Flood Attenuation: 0-60%Vegetation: ¼ to ½ ofpointsWildlife: 0-40%Water Quality: >70%Flood Attenuation:>60%Utilize Vegetation: 0 to ¼ ofpointsWildlife: 0-20%Water Quality: >70%Flood Attenuation:>60%RestoreSouth CreekVegetation: 0 to ½ pointsWildlife: 0 to 20%Field review indicateswetland could be restoredNA – Pertains to SouthCreekLand UseConsiderationsThe futuresurrounding land usewas taken intoconsideration whenchoosing amanagementclassification when awetland’s functionswere scoring betweenmanagementcategories. If thewetland was located ina future greenwaycorridor, park, or Cityproperty, the wetlandwas placed in a moreprotectivemanagement categorythan it may haveotherwise been placed.If the wetland waslocated in an industrialor commercial area, itwas placed in a lessprotectivemanagementclassification.Buffer Requirement b50 Maintenance of existingbounce for a 2-year storm25 ft for wetlands less than2 acres;35 ft for wetlands largerthan 2 acres17 ft for wetlands less than2 acres;25 ft for wetland largerthan 2 acresStormwater Sequencing Mitigation Requirements Management StrategyManagement cImpacts allowed only under extremehardship. Impacts for homes,if feasible; Pretreatment for commercial/ industrial buildings,sediment and nutrients driveways, parking lots, etc. is notallowed. Sequencing must be inconformance with the WCA.Limit bounce to existingplus 0.5 ft for 2-year stormif feasible. Pretreatmentfor sediment and nutrientsSequencing in conformance withWCA.Limit bounce to existing Sequencing in conformance withlevel plus 1.0 ft for 2-year WCA.storm if feasible.Pretreatment for sediment.17 No limit on bounce. Can be Sequencing is outlined within thisused for stormwater Plan. Reference to this sequencingmanagement andmust be made in the application, buttreatmentno additional sequencing is required.25 Limit bounce to existing Sequencing in conformance withlevel plus 1.0 ft for a 2-year WCA.storm if feasible.Pretreatment for sedimentand nutrients50 from centerline of creek(w/ shade spp.), 17 ifwetland extends past 50’centerline. Buffer cannotbe averaged.Replacement at 3:1 ratio with 1.5 acres of NWCminimum and 1.5 acres of PVC maximum.2:1 with 1 acre of NWC minimum and 1 acre ofPVC maximum2:1 with 1 acre of NWC minimum and 1 acre ofPVC maximum. A wetland mitigation fee in-lieuof direct replacement criteria may be used formitigation as determined by the City. This feewill be used by the City to provide mitigation forthese impacted wetlands within 5 years of theproject.Actively protect and preserve functionsand values of wetlands to the maximumextent feasible. Avoid impacts andchanges to hydrology to greatest extentfeasible.Maintain existing functions and values.Maintain existing functions and values.The City will work to provide incentivesto developers who improve the functionsand values of Manage 2 wetlands.At the City’s discretion, replacement at a 1:1 ratio Use for stormwater management.with 0.5 acres of NWC minimum and 0.5 acres ofPVC maximum d with a fee. A wetland mitigationfee in-lieu of all direct wetland mitigation mayalso be used for mitigation as determined by theCity. This fee will be used by the City to providemitigation for these impacted wetlands within 5years of the project.2:1 with 1 acre of NWC minimum and 1 acre ofPVC maximumInfiltration provisions Impacts allowed only under extreme 2:1 with 1 acre of NWC minimum and 1 acre ofprovided prior to discharge hardship and must be in conformance PVC maximumas per South Creek with the WCA.Management PlanUndertake projects/ actions to restorewetland. To promote the restoration ofthese wetlands, the City will provideincentives to developers to restore thesewetlands or undertake restoration as aCity project as feasibleManage for trout stream uses (reducetemperature and promote infiltration)as outlined in the South CreekManagement Plana) See Section IV for more discussion on scoring and management categories.b) Buffer implementation: 17 feet of the required buffer will be platted as an outlot. The remaining buffer width can be included as an outlot or included in the lots provided that homeowners are made aware of the wetland buffer within their lot.Public trails or sidewalks that are a maximum of 10 feet in width can be included within the buffer provided the designated buffer width is maintained. Buffers can be averaged provided that a minimum buffer width of half of the requiredbuffer or 17 feet is maintained, whichever is greater. For wetlands that are within the City’s property, the City anticipates implementing and maintaining these buffers; however, these buffers will not be platted separately.c) Existing two-year HWL for wetlands and water bodies are outlined in the City’s Stormwater Management Plan.d) Program must maintain a no net loss of wetlands as required by the Wetland Conservation Act.LakevilleWater Resources Management Plan Page 5-35

5.4.1 Lakeville Ordinance 10-4-12: WetlandsA. Wetland Application: Every applicant for a grading permit to allow wetland disturbingactivities must submit a report to the environmental resources coordinator. No grading permit toallow wetland disturbing activities shall be issued until approval of the wetland replacement planapplication or a certificate of exemption has been obtained in strict conformance with theprovisions of this title and the Minnesota wetland conservation act. This section applies to allland, public or private, located within the city.B. Wetland Management Plan: Utilization and development impacts to wetlands shall beconsistent with the city's wetland management plan.C. Impacts To Wetland:1. Protective Buffer: A protective buffer of natural vegetation shall surround all wetlandswithin areas developed or redeveloped after March 17, 2003, in accordance with thefollowing provisions:a. Minimum Width: The buffer shall have a minimum width from the delineated edge ofthe wetland at the time of development based upon the wetland classification defined bythe wetland management plan as follows:ClassificationPreserveManage IManage IIUtilizeRestoreWetland mitigation sitesBuffer Requirement50 feet25 feet for wetlands

d. Outlot Plat: The wetland and buffer shall be platted as an outlot if established as part ofa subdivision application. All other applications shall require dedication of a conservationeasement.e. Exception: Property owned by the city of Lakeville shall be exempt from establishing anoutlot or conservation easement for required buffer areas.2. Building Setback:a. For properties developed or redeveloped after March 17, 2003, a building setback of tenfeet (10') for a side yard and twenty feet (20') for a rear yard shall be provided from thedelineated edge of all required wetland buffers at the time of development.b. A building setback of thirty three feet (33') shall exist from the delineated edge of allwetlands at the time of development within areas developed or redeveloped betweenJuly 17, 2000 and March 17, 2003. (Ord. 731, sec. 26, 3-17-2003).Lakeville Water Resources Management Plan Page 5-37

5.5LAKEVILLE ORDINANCE CHAPTER 102 SHORELAND OVERLAYDISTRICT11-102-1: PURPOSE:The purpose of the S, shoreland overlay district is to manage the effect of shoreland and watersurface crowding, to prevent pollution of surface and ground waters of the City, to provide amplespace on lots for sewage treatment systems, to minimize flood damages, to maintain propertyvalues, and to maintain natural characteristics of shorelands and adjacent water areas viashoreland controls which regulate lot sizes, placement of structures and alterations of shorelandareas. (Ord. 674, sec. 1, 7-17-2000)11-102-3: DISTRICT AUTHORIZATION:The shorelands within the city are hereby designated as shoreland districts and the requirementsset forth in this chapter shall govern development and other activities within these districts,pursuant to the authorization and policies contained in Minnesota statutes chapter 103F,Minnesota regulations, parts 6120.2500-6120.3900. The classification of the shoreland areasshall govern the use, alteration, and development of these areas according to said classification.(Ord. 674, sec. 1, 7-17-2000)11-102-5: DISTRICT APPLICATION:The S, shoreland overlay district shall be applied to and superimposed (overlaid) upon all zoningdistricts as identified in chapter 45 of this title as existing or amended by the text and map of thischapter. The regulations and requirements imposed by the S, shoreland overlay district shall bein addition to those established for districts which jointly apply. Under the joint application ofdistricts, the more restrictive requirements shall apply. (Ord. 674, sec. 1, 7-17-2000)11-102-7: DISTRICT BOUNDARIES:The boundaries of the S, shoreland district are established within the following distances fromthe ordinary high-water mark of the surface water depending on the size of the surface water asindicated on the Lakeville shoreland district maps:Surface Water Distance (Feet) 1Greater than 10 acres 1,000Rivers and streams (draining an area greater than 2 square miles) 300 21. The practical distance may be reduced whenever the waters involved are bounded bytopographic divides which extend landward from the waters for lesser distances and whenapproved by the commissioner.2. The distance requirement shall be increased to the limit of the flood plain when greaterthan three hundred feet (300').(Ord. 674, sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-38

11-102-9: SHORELAND CLASSIFICATION:The surface waters affected by this chapter and which require controlled development of theirshoreland (shoreland district) are shown on the map designated as the "Official Shoreland Mapof the City of Lakeville" which is incorporated herein by this reference and filed with the cityclerk. Surface waters generally greater than ten (10) acres are given an identification number bythe state as defined in section 11-102-3 of this chapter and listed in table 1 of this section. Othersurface waters affected by this chapter, generally having less than ten (10) acres, are classified aswetland systems and thus regulated under the provisions of section 11-16-13 of this title.SURFACE WATER IDENTIFICATION - LAKESDNR Name Classification ID. No. / OHWLLake Marion Recreational dev. (RD) 19-26 / 983.1Orchard Lake Recreational dev. (RD) 19-31 / 977.6Crystal Lake Recreational dev. (RD) 19-27 / 934.5Lake Kingsley Natural environment (NE) 19-30 / 978.5Lee Lake Recreational dev. (RD) 19-29 / 948.5Horseshoe Lake Natural environment (NE) 19-32Unnamed Lake Natural environment (NE) 70-11SURFACE WATER IDENTIFICATION - RIVERSNameLocationClassificationUnnamed to Vermillion River (southbranch of North Creek)Unnamed to Unnamed (northbranch of North Creek)Tributary (T)FromSec 8 T114R20Tributary (T) Sec 34T115 R20Unnamed to Unnamed Tributary (T) Sec 17 T114R20Unnamed to Unnamed Tributary (T) Sec 21T114 R20Unnamed to Vermillion River (southbranch of South Creek)Tributary (T) Sec 36T114 R21Unnamed to Unnamed Tributary (T) Sec 19T114 R20ToSec 29T114 R19Sec 12T114 R20Sec 30T114 R19Sec 23T114 R20Sec 36T114 R20Sec 33T114 R2011-102-11: ALLOWABLE LAND USES:The land uses allowable for the S, shoreland overlay district shall follow the "permitted","accessory", and "conditional" use designations as defined and outlined in the base zoningdistricts. (Ord. 674, sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-39

11-102-13: MINIMUM LOT AND SETBACK REQUIREMENTS:Subject to other more restrictive limitations which may be imposed by this title, the followingminimum requirements shall be observed in the following zoning districts which are overlaid bythe S, shoreland overlay district:A. Residential (RS-1, RS-2, RS-3, RS-4, RST-1, RST-2, RS-CBD, RM-1, and RH-1 districts):1. Lot Area:** NE RD Ta. Sewered: (1) Abutting:Single 40,000 20,000Duplex 70,000 35,000Triplex 100,000 50,000Quad 130,000 65,000(2) Nonabutting: **Single 20,000 15,000Duplex 23,000 26,000Triplex 52,000 38,000Quad 65,000 49,000b. Unsewered* 10 acres 10 acres 10 acres2. Lot Width: NE RD Ta. Sewered: ** (1) Abutting:Single 125 75 75Duplex 225 135 115Triplex 325 195 150Quad 425 255 190(2) Nonabutting: **b. Unsewered: (1) Abutting:Single 125 75 75Duplex 220 135 115Triplex 315 190 150Quad 400 245 190Single 200 150 100Duplex 300 225 150Triplex 400 300 200Lakeville Water Resources Management Plan Page 5-40

Quad 500 375 250(2) Nonabutting:Single 200 150 100Duplex 400 265 150Triplex 600 375 200Quad 800 490 250* Lot area requirements in unsewered areas are delineated in section 11-17-19 of this title.** Lot area requirements for rivers in sewered areas are delineated by the base zoning districts.Lot area requirements in unsewered areas are delineated in section 11-17-19 of this title.Residential subdivisions with dwelling unit densities exceeding those in this subsection A canonly be allowed if designed and approved as planned unit developments under section 11-102-21of this chapter. Only land above the ordinary high water level of public waters can be used tomeet lot area standards, and lot width standards must be met at both the ordinary high waterlevel and at the building line. The sewer lot area dimensions in subsection A2a of this section canonly be used if publicly owned sewer system is available to the property.B. All Other Districts: Minimum lot size requirements for all remaining zoning districts notspecified in subsection A of this section are delineated in the various zoning districts definedby chapter 45 of this title.C.Setbacks:1. Ordinary high water mark*** NE RD TSewered 150 feet 75 feet 50 feetUnsewered 150 feet 100 feet 100 feet2. Top of bluff**** 30 feet 30 feet 30 feet3. Unplatted cemetery 50 feet 50 feet 50 feet4. Setback from public streets5. Side yardRight of way line of federal, state, or county road 50 feet 50 feet 50 feetRight of way line of city street 30 feet 30 feet 30 feetSetback for property abutting a lake***** 20 feet 20 feet 20 feet*** Setback requirements from the ordinary high water mark shall not apply to piers anddocks. Where development exists on both sides of a proposed building site, building setbacksmay be altered to more closely conform to adjacent building setbacks, provided the proposedbuilding site is not located in a shore impact zone or in a bluff impact zone. (Ord. 674, sec. 1,7-17-2000)Lakeville Water Resources Management Plan Page 5-41

**** Any new subdivisions, lot combinations or replats of existing lots of record shall berequired to conform to the thirty foot (30') setback from the top of bluff based upon thedefinition within section 11-2-3 of this title.Structure setback on existing lots of record prior to March 1, 1993, shall be allowed up totwenty feet (20') from the top of bluff. The location of top of bluff for existing lots of recordprior to March 1, 1993, shall be determined as provided for by section 11-2-3 of this title,except by conditional use permit to allow for expansion of existing principal dwellingssubject to the following requirements:a. Top of the bluff is the point, visually observed, at a clearly identifiable break in the slopefrom steeper to gentler above the slope and away from the water body. If no break in theslope is apparent based on visual observation, the top of bluff shall be determined basedupon the definition within section 11-2-3 of this title.b. Toe of the bluff is the point, visually observed, at a clearly identifiable break in the slopefrom gentler to steeper above the slope and away from the water body. If no break in theslope is apparent based upon visual observation, the toe of bluff shall be determined basedupon the definition within section 11-2-3 of this title.c. Any development allowed under the alternative definition for top of the bluff will notincrease the area or rate of storm water drainage towards the water body.d. Engineered grading and construction plans for any structures are provided demonstratingthat the development will not degrade the physical integrity of the bluff.e. A shoreland impact plan is prepared and submitted in accordance with section 11-102-17 ofthis chapter.f. In addition to the information required by section 11-4-5 of this title and section 11-102-17of this chapter, application for a CUP under this subsection shall require submission of across section of the parcel, drawn to scale, identifying the following:(1) Ordinary high water mark.(2) Toe of the bluff.(3) Top of the bluff.(4) Bluff impact zone.(5) Structure location(s). (Ord. 708, sec. 1, 3-18-2002)***** Subject to regulations and exceptions as provided in the various zoning districtsestablished by chapter 45 of this title. The required side yard setback on all lots of recordplatted prior to January 18, 1980, is ten feet (10').D. Maximum Building Height: Building height shall be regulated by section 11-17-7 of thistitle.E. Impervious Surface Coverage:1. Impervious surface coverage limits shall apply only to that portion of the lot lyingwithin the S, shoreland overlay district.2. Impervious surface coverage for lots in all zoning districts shall not exceed twenty fivepercent (25%) of the lot area, except as provided below:Lakeville Water Resources Management Plan Page 5-42

a. Where appropriate and where structures and practices for the mitigation ofstormwater impacts on receiving waters are employed in compliance with theComprehensive Storm Drainage Plan for the City, or as approved by the City Engineer,impervious surface coverage shall be allowed to exceed twenty five percent (25%)impervious coverage to a maximum of seventy five percent (75%) impervious surfacecoverage per lot within all industrial zoning districts located on tributary rivers, seventypercent (70%) impervious surface coverage per lot within all business and CBD zoningdistricts located on recreational development (RD) lakes, and tributary rivers and to amaximum of fifty percent (50%) impervious surface coverage per lot within all businesszoning districts on natural environment (NE) lakes provided the following criteria aremet:(1) All structures and practices are in place for the treatment of stormwater runoff.(2) A conditional use permit and shoreland impact plan are submitted and approvedas provided for in Sections 11-102-17 and 11-102-25 of this Title.(3) Any removal of significant trees shall require a tree preservation plan inaccordance with the City's tree preservation guidelines.b. Measures for the treatment of stormwater runoff and/or prevention of stormwaterfrom directly entering a public water include such appurtenances as nutrient removalbasins and other measures described in the MPCA guidance document for bestmanagement practices for stormwater quality protection in urban areas. (Ord. 674, sec. 1,7-17-2000)11-102-15: NONCONFORMITIES:Any lot of record filed in the office of the Dakota County Recorder prior to June 19, 1978, whichdoes not meet the requirements of subsection 11-102-13A of this Chapter may be allowed as abuilding site provided the lot meets the requirements of Section 11-16-5 of this Title, and subjectto approval of a shoreland impact plan.A. Construction On Nonconforming Lots Of Record: If, in a group of two (2) or morecontiguous lots under the same ownership, any individual lot does not meet therequirements of Section 11-102-13 of this Chapter the lot shall not be considered as aseparate parcel of land for the purpose of sale or development. The lot must be combinedwith the one or more contiguous lots so they equal one or more parcels of land, each meetingseventy percent (70%) of the lot area and lot width requirements of this Chapter, providedeach lot has access to public sewer and lot development can comply with all requiredsetbacks. Effective January 1, 1999, separate lots of record on that day may not be combinedto meet seventy percent (70%) lot area and lot width requirements of subsection 11-15-9B3aof this Title.B. Additions/Expansions To Nonconforming Structures: All additions or expansions to theoutside dimensions of an existing nonconforming single-family structure shall be allowed byconditional use permit provided the addition or expansion meets the setback, height, andother requirements of Section 11-102-13 of this Chapter. Any deviation from theserequirements shall be authorized by a variance pursuant to Section 11-102-23 and Chapter 6of this Title.Lakeville Water Resources Management Plan Page 5-43

C. Nonconforming Sewage Treatment Systems: All sanitary facilities on lots outside ofLakeville's urban service area inconsistent with requirements of this Chapter shall bebrought into conformity within two (2) years after the effective date hereof, or discontinuedimmediately when there is evidence of septic tank effluent percolating from the ground,flowing directly into a lake or stream, or other indications of system failure. (Ord. 674, sec. 1,7-17-2000)11-102-17: DEVELOPMENT REGULATIONS:A. Shoreland Impact Plan:1. Generally: Landowners or developers desiring to develop land or construct anydwelling or any other structure on land located within any shoreland district within theCity shall first submit a conditional use permit application as regulated by Chapter 4 ofthis Title and a plan of development, thereinafter referred to as "shoreland impact plan",which shall set forth proposed provisions for sediment control, water management,maintenance of landscaped features, and any additional matters intended to improve ormaintain the quality of the environment. Such a plan shall set forth proposed changesrequested by the applicant and affirmatively disclose what, if any, change will be made inthe natural condition of the land, including loss or change of ground cover, destruction oftrees, grade courses, marshes, and wetlands. The plan shall minimize tree removal,ground cover change, loss of natural vegetation, and grade changes as much as possible,and shall affirmatively provide for the relocation or replanting of as many trees aspossible which are proposed to be removed. The purpose of the shoreland impact planshall be to eliminate as much as possible potential pollution, erosion and siltation.2. Exceptions:a. No conditional use permit or shoreland impact plan shall be required for thedevelopment of permitted uses contained within the A-P, RA, RAO, RS-1, RS-2, RS-3, orRS-4 Districts provided that such uses are constructed on conforming lots and whenabutting a shoreline that all such uses are serviced with public sanitary sewer, or arelocated on lots which are ten (10) acres or more in size.b. No conditional use permit or shoreland impact plan shall be required for thedevelopment of permitted accessory uses within the A-P, RA, RAO, RS-1, RS-2, RS-3, orRS-4 Districts.B. Bluff Impact Zones: Structures and accessory facilities except stairways, landings, andpublic utilities shall not be placed within bluff impact zones.C. Stairways, Lifts, And Landings: Stairways and lifts, solely for the purpose of pedestriantransportation, are the preferred alternative to major topographic alterations for achievingaccess up and down bluffs and steep slopes to shore areas. Stairways and lifts must meet thefollowing design requirements:1. Stairways and lifts shall not exceed four feet (4') in width on residential lots. Widerstairways may be used for commercial properties, public open-space recreationalproperties, and planned unit developments;Lakeville Water Resources Management Plan Page 5-44

2. Landings for stairways and lifts on residential lots shall not exceed thirty two (32)square feet in area;3. Canopies or roofs are not allowed on stairways, lifts, or landings;4. Stairways, lifts, and landings may be either constructed above the ground on posts orpilings, no higher than thirty inches (30") above grade at any one point, or placed intothe ground provided they are designed and built in a manner that ensures control of soilerosions;5. Stairways, lifts, and landings shall be located in the most visually inconspicuousportions of lots, as viewed from the surface of the public water assuming summer, leaf-onconditions, whenever practical; and6. Facilities such as ramps, lifts, or mobility paths for physically handicapped persons arealso allowed for achieving access to shore areas, provided that the dimensional andperformance standards of subsection C1 through C4 of this Section are complied withinaddition to the requirements of Minnesota Regulations, chapter 1340.D. Steep Slopes: The City Engineer shall evaluate possible soil erosion impacts anddevelopment visibility from public waters before issuing a permit for construction of sewagetreatment systems, roads, driveways, structures, or other improvements on steep slopes.When determined necessary, conditions must be attached to issued permits to preventerosion and to preserve existing vegetation screening of structures, vehicles, and otherfacilities as viewed from the surface of public waters, assuming summer, leaf-on vegetation.E. Sewage And Waste Disposal: Any premises used for human occupancy shall be providedwith an adequate method of sewage disposal to be maintained in accordance with acceptablepractices.1. Public Safety Sewers: Public safety sewer collection and treatment facilities shall beused where available, and where feasible.2. Private Sewage Systems: All private sewage treatment systems must meet or exceedthe Minnesota Pollution Control Agency's standards for individual sewage treatmentsystems contained in the document "Individual Sewage Treatment Systems Standards,Chapter 7080", the rules and regulations of the Minnesota Department of Health, andDakota County.3. Drain Fields: A septic tank-drain field system shall be the only acceptable system forinstallation unless it can be demonstrated that this system is not feasible on theparticular lot in question and it can be demonstrated that the system being proposed asan alternate will not cause a pollution problem.4. Individual Systems:a. Generally: All proposed sites for individual sewage treatment systems shall beevaluated in accordance with the criteria in the following subsection E4b of this Section.If the determination of a site's suitability cannot be made with publicly available, existinginformation, it shall then be the responsibility of the applicant to provide sufficient soilborings and percolation tests from on-site field investigations.b. Evaluation Criteria:(1) Depth to the highest known or calculated ground water table or bedrock;(2) Soil conditions, properties, and permeability;Lakeville Water Resources Management Plan Page 5-45

(3) Slope;(4) The existence of lowlands, local surface depressions, and rock outcrops; and(5) Nonconforming sewage treatment systems shall be regulated and upgraded inaccordance with subsection 11-102-15C of this Chapter.5. Permit Required: No person may install, alter, repair or extend any individual sewagedisposal system without first obtaining a permit therefor from the City for the specificinstallation alteration, repair or extension.6. Placement: Placement of septic tank soil absorption systems shall be subject to thefollowing setback requirements where soil conditions are adequate:a. On natural environment lakes, at least one hundred fifty feet (150') from the normalhigh-water mark.b. On recreational development lakes, at least seventy five feet (75') from the normalhigh-water mark.c. On tributary streams, at least seventy five feet (75') from the normal high-water mark.7. Soil Absorption Systems: Soil absorption systems shall not be allowed in the followingareas for disposal of domestic sewage.a. Low swampy areas or areas subject to recurrent flooding.b. Areas where the highest known ground water table, bedrock or impervious soilsconditions are within three feet (3') of the bottom of the system.c. Areas of ground slope which create a danger of seepage of the effluent onto the surfaceof the ground.d. Areas lying within the 50-year flood plain.F. Water Supply: Any private supply of water for domestic purposes shall conform toMinnesota Pollution Control Agency, Dakota County, and Minnesota Department of HealthStandards for water quality. Private wells shall be placed in areas not subject to flooding andup slope from any source of contamination. Wells already existing in areas subject toflooding shall be floodproofed in accordance with State Building Code standards. No privatewells shall be located closer than three feet (3') to the outside basement wall of a dwelling.The outside basement footing shall be continuous across the opening of the well alcove. Nowell shall be located closer than ten feet (10') to a property line.G. Stormwater Management: The following general and specific standards shall apply inregard to stormwater management within any shoreland district within the City:1. When possible, existing natural drainageways, wetlands, and vegetated soil surfacesshall be used to convey, store, filter, and retain stormwater runoff before discharge topublic waters.2. Development shall be planned and conducted in a manner that will minimize theextent of disturbed areas, runoff velocities, erosion potential, and reduce and delayrunoff volumes. Disturbed areas shall be stabilized and protected as soon as possible, andno later than thirty (30) days after completion of the project. All methods of stormwatermanagement shall comply with the Lakeville Comprehensive Storm Drainage Plan.3. When development density, topographic features, and soil and vegetation conditionsare not sufficient to adequately handle stormwater runoff using natural features andvegetation, various types of constructed facilities such as diversions, settling basins,Lakeville Water Resources Management Plan Page 5-46

skimming devices, dikes, waterways, and ponds may be used. Preference shall be given todesigns using surface drainage, vegetation, and infiltration rather than buried pipes andmanmade materials and facilities.4. When constructed facilities are used for stormwater management, documentation shallbe provided by a qualified individual that they are designed and installed consistent withthe field office technical guide of the Dakota County Soil and Water ConservationDistrict.5. New constructed stormwater outfalls to public waters shall provide for filtering orsettling of suspended solids and skimming of surface debris before discharge.H. Placement And Design Of Roads, Driveways, And Parking Areas: The following standardsshall apply in regard to roadway, driveway and parking area placement and design withinany shoreland district within the City.1. Public and private roads and parking areas shall be designed to take advantage ofnatural vegetation and topography to achieve maximum screening from view from publicwaters. Documentation shall be provided by the City Engineer that all roads and parkingareas are designed and constructed to minimize and control erosion to public watersconsistent with the field office technical guides of the Dakota County Soil and WaterConservation District.2. Private roads, driveways, and parking areas shall meet structure setbacks and shall notbe placed within bluff and shore impact zones, when other reasonable and feasibleplacement alternatives exist. If no alternatives exist, they may be placed within theseareas by conditional use permit, and must be designed to minimize adverse impacts.Natural vegetation or other natural materials shall be required in order to screen parkingareas when viewed from the water. Parking areas of more than four (4) spaces shall bescreened in accordance with a landscape plan, submitted and approved by the CityCouncil.3. Public and private watercraft access ramps, approach roads, and access-relatedparking areas may be placed within shore impact zones provided the vegetative screeningand erosion control conditions of this subpart are met. For private facilities, the gradingand filling provisions of subsection 11-102-19B of this Chapter shall be met.I. Fences: Fences shall not exceed forty two inches (42") in height and shall be at leastseventy five percent (75%) open space for passage of air and light inside the ordinary highwaterlevel setback. Fences shall not be located within ten feet (10') from the ordinary highwatermark. (Ord. 674, sec. 1, 7-17-2000)11-102-19: SHORELAND ALTERATIONS:Alterations of vegetation and topography will be regulated to prevent erosion into public waters,fix nutrients, preserve shoreland aesthetics, preserve historic values, prevent bank slumping, andprotect fish and wildlife habitat.A. Vegetation Alterations: The removal of natural vegetation shall be restricted to preventerosion into public waters, to conserve nutrients in the soil, and to preserve shorelandaesthetics.Lakeville Water Resources Management Plan Page 5-47

1. During the site grading of new subdivision development and other planning actions,any removal of significant trees shall require a tree preservation plan in accordance withthe City's tree preservation guidelines.2. Natural vegetation shall be restored as soon as feasible after any construction project,but not later than the start of the next growing season.3. The provisions of this Section shall not apply to vegetation alterations necessary forthe construction of structures, sewage treatment systems and the construction of roadsand parking areas as regulated in subsection 11-102-17H of this Chapter subject to thefollowing standards:a. Intensive vegetation clearing within the shore and bluff impact zones and on steepslopes is not allowed. Intensive vegetation clearing for forest land conversion to anotheruse outside of these areas is allowable as a conditional use if an erosion control andsedimentation plan is developed consistent with the field office technical guides of theDakota County Soil and Water Conservation District.b. In shore and bluff impact zones and on steep slopes, limited clearing of trees andshrubs and cutting, pruning, and trimming of trees is allowed to provide a view to thewater from the principal dwelling site and to accommodate the placement of stairwaysand landings, access paths, beach and watercraft access areas or facilities, provided that:(1) The screening of structures, vehicles, or other facilities as viewed from the water,assuming summer, leaf-on conditions, is not substantially reduced.(2) Along rivers, existing shading of water surfaces is preserved.(3) The above provisions are not applicable to the removal of trees, limbs, orbranches that are dead, diseased, or pose safety hazards.B. Grading And Filling Associated With Any Development Project Involving Subdivisions,Commercial, Industrial, Or Multiple- Family Uses:1. Grading and filling within shoreland districts, or any alterations of the naturaltopography where the slope of the land is toward a public water or watercourse leading toa public water shall be consistent with the field office technical guides of the DakotaCounty Soil and Water Conservation District and approved by the City Engineer. Apermit shall be obtained prior to the commencement of any work thereon. The permitmay be granted subject to the conditions that:a. Temporary ground cover such as mulch shall be used and permanent cover such as sodshall be planted as soon as possible.b. Methods to prevent erosion and trap sediment shall be employed in accordance withthe Lakeville Subdivision Ordinance 26 and consistent with the field office technicalguides of the Dakota County Soil and Water Conservation District.c. Fill shall not be placed in areas lower in elevation than the normal high-water mark.d. Fill shall be stabilized according to accepted engineering standards.e. Fill shall not restrict a floodway or destroy the storage capacity of a flood plain.f. The maximum slope of the finished surface which slopes toward a water body or awatercourse leading to such water body shall be three (3) units horizontal to one vertical.g. Fill or excavated material must not be placed in bluff impact zones.h. Any alterations below the ordinary high-water level of public waters must first beauthorized by the Commissioner under Minnesota Statutes section 103G.245.Lakeville Water Resources Management Plan Page 5-48

i. Alterations of topography will only be allowed if they are accessory to permitted orconditional uses and do not adversely affect adjacent or nearby properties.j. Placement of natural rock riprap, including associated grading of the shoreline andplacement of a filter blanket, is permitted if the finished slope does not exceed three feet(3') horizontal to one foot (1') vertical, the landward extent of the riprap is within ten feet(10') of the ordinary high-water level, and the height of the riprap above the ordinaryhigh-water level does not exceed three feet (3').2. Any work which will change or diminish the course, current, or cross section of apublic water shall require a permit from the City Engineer and be approved by theDepartment of Natural Resources before the work is begun. This includes construction ofboat slips, canals, channels and ditches, lagooning, dredging of lake bottom for theremoval of muck, silt or weeds, and filling in the lake bed including low lying marshareas. Approval will be given only if the proposed work is consistent with applicable Stateregulations for beds of public waters.C. Special Provisions For Agricultural, Extractive, And Commercial Uses:1. Agriculture Use Standards:a. General cultivation farming, grazing, nurseries, horticulture, truck farming, sodfarming, and wild crop harvesting are permitted uses if steep slopes and shore andbluff impact zones are maintained in permanent vegetation or operated under anapproved conservation plan (resource management systems) consistent with the fieldoffice technical guides of the Dakota County Soil and Water Conservation District orthe United States Soil Conservation Service, as provided by a qualified individual oragency. The shore impact zone for parcels with permitted agricultural land uses isequal to a line parallel to and fifty feet (50') from the ordinary high water level.b. Use of fertilizer, pesticides, or animal wastes within shorelands must be done insuch a way as to minimize impact on the shore impact zone or public water by properapplication or use of earth or vegetation.2. Extractive Use Standards: All excavations and mining within the S, shoreland overlaydistrict shall be in compliance with the Lakeville excavations and mining ordinance, title7, chapter 4 of this code.3. Commercial Use Standards: Uses without water oriented commercial needs located onprotected lakes must be located on lots or parcels without public waters frontage, or, iflocated on lots or parcels with public waters frontage, must either be set back double thenormal ordinary high water level setback or be substantially screened from view from thewater by vegetation or topography, assuming summer, leaf-on conditions. (Ord. 674, sec.1, 7-17-2000)11-102-21: PLANNED SHORELAND DEVELOPMENT:Flexible application of the allowable land uses, minimum lot area and setback requirements anddevelopment regulations of this chapter may be used within a shoreland district, provided thatthe following requirements are satisfactorily met:A. Conditional Use Permit: Planned shoreland developments shall require a conditional usepermit based upon procedures set forth in and regulated by chapter 4 of this title.Lakeville Water Resources Management Plan Page 5-49

B. Sewer And Water: Planned shoreland developments shall be connected to municipalsewer and water.C. Open Space: Residential planned shoreland developments shall contain open spacemeeting all of the following criteria:1. At least fifty percent (50%) of the total project area shall be preserved as open space.2. Dwelling units or sites, road rights of way, or land covered by road surfaces, parkingareas, or structures, except water oriented accessory structures or facilities, aredeveloped areas and shall not be included in the computation of minimum open space.3. Open space shall include areas with physical characteristics unsuitable fordevelopment in their natural state.4. Open space may include outdoor recreational facilities for use by owners of dwellingunits or sites.5. The appearance of open space areas, including topography, vegetation, and allowableuses, shall be preserved by use of restrictive deed covenants, permanent easements,public dedication and acceptance, or other equally effective and permanent means.6. The shore impact zone, based on normal structure setbacks, shall be included as openspace. At least fifty percent (50%) of the shore impact zone area of existing developmentsor at least seventy percent (70%) of the shore impact zone area of new developmentsmust be preserved in its natural or existing state.D. Residential Density Evaluation:1. Procedures And Standards: Proposed new or expansions to existing planned shorelanddevelopments shall be evaluated using the following procedures and standards todetermine the suitable area for the dwelling unit/dwelling site density evaluation insubsection D2 of this section.a. The project parcel shall be divided into tiers by locating one or more linesapproximately parallel to a line that identifies the ordinary high water level at thefollowing intervals, proceeding landward:SHORELAND TIER DIMENSIONSUnsewered (Ft)Sewered (Ft)Recreational development lakes 267 267Natural environment lakes 400 320All rivers 300 300b. The suitable area within each tier is next calculated by excluding from the tier area allwetlands, bluffs, or land below the ordinary high water level of public waters. Thissuitable area and the proposed project are then subjected to the residential plannedshoreland development density evaluation steps to arrive at an allowable number ofdwelling units or sites.Lakeville Water Resources Management Plan Page 5-50

2. Residential Base Density Evaluation: The procedures for determining the base densityand density increase multipliers are as follows. Allowable densities may be transferredfrom any tier to any other tier further from the water body, but must not be transferredto any other tier closer.a. Formula: The suitable area within each tier is divided by the single residential lot sizestandard for lakes and rivers. Proposed locations and numbers of dwelling units or sitesfor the residential planned shoreland developments are then compared with the tier,density, and suitability analysis herein and the design criteria in this subsection D.b. Increases: Increases to the dwelling unit or dwelling site base densities previouslydetermined are allowable if the dimensional standards for the various zoning districtsestablished by chapter 45 of this title are met or exceeded and the design criteria in thissubsection D are satisfied. The allowable density increases in subsection D2c of thissection will only be allowed if structure setbacks from the ordinary high water level areincreased to at least fifty percent (50%) greater than the minimum setback, or the impacton the water body is reduced an equivalent amount through vegetative management,topography, or additional means acceptable to the local unit of government and thesetback is at least twenty five percent (25%) greater than the minimum setback.c. Allowable Dwelling Unit Or Dwelling Site Density Increases For Residential PlannedShoreland Developments:Density Evaluation Tiers Within Each Tier (%)First 50Second 100Third 200Fourth 200Fifth 200E. Erosion Control And Storm Water Management: Erosion control and storm watermanagement plans shall be prepared for all planned shoreland developments and shall beconsistent with subsection 11-102-17G of this chapter.F. Centralization And Design Of Facilities: Centralization and design of facilities andstructures shall be done according to the following standards:1. Dwelling units or sites shall be clustered into one or more groups and located onsuitable areas of the development. They shall be designed and located to meet or exceedthe following dimensional standards for the relevant shoreland classification. Setbackfrom the ordinary high water level, elevation above the surface water features, andmaximum height. Setbacks from the ordinary high water level shall be increased inaccordance with subsection D2 of this section for developments with density increases.2. Structures, parking areas, and other facilities shall be treated to reduce visibility asviewed from the public waters and adjacent shorelands by vegetation, topography,increased setbacks, color, or other means acceptable to the local unit of government,Lakeville Water Resources Management Plan Page 5-51

assuming summer, leaf-on conditions. Vegetative and topographic shall be preserved, ifexisting, or may be required to be provided.3. Accessory structures and facilities shall meet the required principal structure setbackand must be centralized.G. Evaluation Of Factors: The following factors are carefully evaluated to ensure that theincreased density of development is consistent with the resource limitations of the publicwater:1. Suitability of the site for the proposed use.2. Physical and aesthetic impact of increased density.3. Level of current development.4. Amount of ownership of undeveloped shoreland.5. Levels and types of water surface use and public access.6. Possible effects on overall public use.H. Facilities: Any recreational or community facility allowed as part of the plannedshoreland development conforms to all applicable federal and state regulations including,but not limited to, the following:1. Waste disposal regulations.2. Water supply regulations.3. Building codes.4. Safety regulations.5. Regulations concerning the appropriate use of "public waters" as defined in Minnesotastatutes section 103G.245.6. Applicable regulations of the Minnesota environment quality council.7. Storm sewer.I. Alteration Approval: The final planned shoreland development shall not be modified oraltered in any way without written approval from the department of natural resources.J. Central Shoreline Facilities: Planned shoreland developments incorporating shorelinerecreational facilities such as beaches, docks, or boat launching facilities, etc., shall bedesigned such that said facilities are centralized for common utilization. (Ord. 730, sec. 41, 3-17-2003)11-102-23: VARIANCES:Variances may be granted by the city council upon application as required in chapter 6 of thistitle in extraordinary cases, but only when the proposed use is determined to be in the publicinterest and no variance shall be granted which the council determines will or has a tendency to:A. Result in the placement of an artificial obstruction which will restrict the passage of stormand flood water in such a manner as to increase the height of flooding, except obstructionsapproved by the watershed districts in conjunction with sound floodplain management.Lakeville Water Resources Management Plan Page 5-52

B. Result in incompatible land uses or which would be detrimental to the protection ofsurface and ground water supplies.C. Be not in keeping with land use plans and planning objectives for the city or which willincrease or cause damage to life or property.D. Be inconsistent with the objectives of encouraging land uses compatible with thepreservation of the natural land forms, vegetation and the marshes and wetlands within thecity.E. No permit or variance shall be issued unless the applicant has submitted a shorelandimpact plan as required and set forth in this chapter. In granting any variance, the councilmay attach such conditions as they deem necessary to ensure compliance with the purposeand intent of this chapter. (Ord. 674, sec. 1, 7-17-2000)11-102-25: CONDITIONAL USES:Conditional uses allowable within shoreland areas shall be subject to the review and approvalprocedures set forth in chapter 4 of this title. The following additional evaluation criteria andconditions apply within shoreland areas:A. Evaluation Criteria: A thorough evaluation of the water body and the topographic,vegetation, and soils conditions on the site must be made to ensure:1. The prevention of soil erosion or other possible pollution of public waters, both duringand after construction.2. The visibility of structures and other facilities as viewed from public waters is limited.3. The site is adequate for water supply and on site sewage treatment. (Ord. 674, sec. 1, 7-17-2000)11-102-27: NOTIFICATIONS TO THE DEPARTMENT OF NATURAL RESOURCES:A. Copies of all notices of any public hearings to consider variances, amendments, orconditional uses under local shoreland management controls must be sent to thecommissioner or the commissioner's designated representative and postmarked at least ten(10) days before the hearings. Notices of hearings to consider proposed subdivisions/plansmust include copies of the subdivision/plat.B. A copy of approved amendment and subdivisions/plats, and final decisions grantingvariances or conditional uses under local shoreland management controls must be sent to thecommissioner or the commissioner's designated representative and postmarked within ten(10) days of final action. (Ord. 674, sec. 1, 7-17-2000)11-102-29: EFFECT OF PERMIT:The granting of any permit, variance, or subdivision approval under provisions of this chaptershall in no way affect the owner's capability to obtain the approval required by any other statute,ordinance or legislation of any state agency or subdivision thereof. Approval may be expresslygiven in conjunction with other permits applied for, but no approval shall be implied from thegrant of such permits nor from the necessity to apply for a permit as described herein. (Ord. 674,sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-53

5.6LAKEVILLE ORDINANCE CHAPTER 101: FLOOD PLAIN OVERLAYDISTRICT11-101-1: STATUTORY AUTHORIZATION, FINDINGS OF FACT, AND PURPOSE:The legislature of the State has, in Minnesota Statutes chapters 104 and 462, as may beamended, delegated the responsibility to local government units to adopt regulations designed tominimize flood losses. Therefore, the City does ordain as follows:A. Findings Of Fact:1. Periodic Inundation: The flood hazard areas of the City are subject to periodicinundation which results in potential loss of life, loss of property, health and safetyhazards, disruption of commerce and governmental services, extraordinary publicexpenditures on flood protection and relief, and impairment of the tax base, all of whichadversely affect the public health, safety, and general welfare.2. Methods Used To Analyze Flood Hazards: This Chapter is based upon a reasonablemethod of analyzing flood hazards which is consistent with the standards established bythe Minnesota Department of Natural Resources.B. Statement Of Purpose: It is the purpose of this District to promote the public health,safety, and general welfare and to minimize those losses described in subsection A of thisSection by provisions contained herein. (Ord. 674, sec. 1, 7-17-2000)11-101-3: WARNING AND DISCLAIMER OF LIABILITY:This Chapter does not imply that areas outside the FP Flood Plain Overlay District boundaries orland uses allowed within this District will be free from flooding or flood damages. This Chaptershall not create liability on the part of the City or any officer or employee thereof for any flooddamages which result from reliance on this Chapter or any administrative decision lawfully madethereunder. (Ord. 674, sec. 1, 7-17-2000)11-101-5: DISTRICT APPLICATION:The FP, Flood Plain Overlay District shall be applied to and superimposed upon all districts asexisting or amended by the text and map of this Chapter. The FP, Flood Plain Overlay Districtregulations shall not be construed to allow any use or structure otherwise not allowed in theunderlying zoning district where the property is located. The regulations and requirementsimposed by the FP Flood Plain Overlay District shall be in addition to those established by allother districts of this Title. The FP Flood Plain Overlay District shall be established based uponthe specific information contained in the Flood Insurance Rate Map and the Flood InsuranceStudy for the City as adopted in subsection 11-101-7B of this Chapter. All aforementioned officialroad maps and documents are hereby adopted by reference and declared to be an integral part ofthis Chapter. (Ord. 674, sec. 1, 7-17-2000)11-101-7: GENERAL PROVISIONS:A. Lands To Which The Chapter Applies: This District shall apply to all lands within thejurisdiction of the City shown on the Official Zoning Map and the Flood Insurance Rate MapLakeville Water Resources Management Plan Page 5-54

attached thereto as being located within the boundaries of the areas designated as Zone AE orZone A.B. Establishment Of Official Zoning Map:1. Adoption: The Official Zoning Map together with all materials attached thereto is herebyadopted by reference and declared to be a part of this Chapter. The attached material shallinclude the Flood Insurance Study and Flood Insurance Rate Map for the City, dated April20, 1998, as may be amended. The Official Zoning Map shall be on file in the office of the CityClerk and the Zoning Administrator.2. Regulatory Flood Protection Elevation: The regulatory flood protection elevation shall bean elevation no lower than one foot (1') above the elevation of the 100-year base regionalflood elevation plus any increases in flood elevation caused by encroachments on the floodplain that result from designation of floodway.3. Regional Flood Elevation For Lakes: The base regional flood level for lakes shall be asdefined on the current Flood Insurance Rate Map or on the August 27, 1997, letter from theFederal Emergency Management Agency to the City. These elevations are as follows:LakeRegional Base Flood ElevationCrystal Lake 936.0Goose Lake 1,083.7Kingsley Lake 982.4Lake Marion 985.0Lee Lake 953.1Orchard Lake 978.4Raven Lake 1,100.1C. Rules For Interpretation Of District Boundaries: The boundaries of the Flood Plain OverlayDistrict shall be determined by scaling distances on the Official Zoning Map. Whereinterpretation is needed as to the exact location of the boundaries of the District as shown on theOfficial Zoning Map, as for example, where there appears to be a conflict between a mappedboundary and actual field conditions, the City Engineer shall make the necessary interpretation.The persons contesting the location of the District boundary shall be given a reasonableopportunity to present their case and to submit their own technical evidence if they so desire.(Ord. 674, sec. 1, 7-17-2000)11-101-9: ESTABLISHMENT OF ZONING DISTRICTS:A.Floodway Subdistricts: The area within the FP Flood Plain Overlay District is furtherdivided into three (3) districts:1. FW, Floodway District: The FW District includes the bed of a lake or wetland or thechannel of a river or stream and those portions of the adjoining flood plain which areintended to store or carry and discharge, respectively, the regional flood. The FloodwayDistrict shall include those areas designated as floodway on the Flood Insurance RateMap adopted in subsection 11-101-7B of this Chapter.Lakeville Water Resources Management Plan Page 5-55

2. FF, Flood Fringe District: Includes the area outside of the floodway, but subject toinundation by the 100-year regional floods. The Flood Fringe District shall include thoseareas designated as floodway fringe on the Flood Insurance Rate Map adopted insubsection 11-101-7B of this Chapter.3. GFD, General Flood Plain District: The General Flood Plain District shall include thoseareas designated as unnumbered "A" zones on the Flood Insurance Rate Map adopted insubsection 11-101-7B of this Chapter. (Ord. 674, sec. 1, 7-17-2000)11-101-11: FW, FLOODWAY DISTRICT:A. Permitted Uses:1. General farming, pasture, grazing, outdoor plant nurseries, horticulture, truck farming,forestry, sod farming, and wild crop harvesting.2. Industrial-commercial loading areas, parking areas, and airport landing strips.3. Private and public golf courses, tennis courts, driving ranges, archery ranges, picnicgrounds, boat launching ramps, swimming areas, parks, wildlife and nature preserves,game farms, fish hatcheries, shooting preserves, target ranges, trap and skeet ranges,hunting and fishing areas, and single or multiple purpose recreational trails includingpedestrian bridges.4. Residential lawns, gardens, parking areas, and play areas.5. Public utilities, sanitary sewer, public water, storm sewer, and street improvements.B. Standards For Floodway Permitted Uses:1. The use shall have a low flood damage potential.2. The use shall not obstruct flood flows or increase flood elevations and shall not involvestructures, fill, obstructions, excavations or storage of materials or equipment.C. Permitted Accessory Uses: None.D. Conditional Uses:1. Structures accessory to the uses listed in subsection A of this Section, and the useslisted in subsection D2 through D8 of this Section.2. Extraction and storage of sand, gravel, and other materials.3. Marinas, boat rentals, docks, piers, wharves, and water control structures.4. Railroads, streets, bridges, utility transmission lines, and pipelines.5. Storage yards for equipment, machinery, or materials.6. Placement of fill.7. Travel trailers and travel vehicles either on individual lots of record or in existing ornew subdivisions or commercial or condominium type campgrounds, subject to theexemptions and provisions of Section 11-101-21 of this Chapter.8. Structural works for flood control such as levees, dikes and floodwalls constructed toany height where the intent is to protect individual structures and levees or dikes wherethe intent is to protect agricultural crops for a frequency flood event equal to or less thanthe 10-year frequency flood event.Lakeville Water Resources Management Plan Page 5-56

E. Standards For Floodway Conditional Uses: No structure (temporary or permanent), fill(including fill for roads and levees), deposit, obstruction, storage of materials or equipment,or other uses may be allowed as a conditional use which, acting alone or in combination withexisting or anticipated future uses, adversely affect the capacity of the floodway, or increaseflood heights, with the exception of floodway boundary amendments. Consideration of theeffects of a proposed use shall be based upon the reasonable assumption that there will be anequal degree of encroachment extending for a significant reach on both sides of the stream.All conditional use applications shall be accompanied by a floodway impact statementdrafted by a registered engineer. The City Engineer shall be responsible for submitting theproposal and application to the Department of Natural Resources and any othergovernmental unit having jurisdiction over the area for review and comment.1. Fill, dredge spoil and all other similar materials deposited or stored in the flood plainshall be protected from erosion by vegetative cover, mulching, riprap or other acceptablemethod.2. Dredge spoil sites and sand and gravel operations shall not be allowed in the floodwayunless a long-term site development plan is submitted which includes anerosion/sedimentation prevention element to the plan.3. As an alternative, and consistent with subsection E2 of this Section, dredge spoildisposal and sand and gravel operations may allow temporary, on-site storage of fill orother materials which would have caused an increase to the stage of the 100-year orregional flood but only after the governing body has received an appropriate plan whichassures the removal of the materials from the floodway based upon the flood warningtime available. The conditional use permit must be title registered with the property inthe office of the County Recorder.F. Accessory Structures:1. Accessory structures shall not be designed for human habitation.2. Accessory structures, if permitted, shall be constructed and placed on the building siteso as to offer the minimum obstruction to the flow of flood waters.a. Whenever possible, structures shall be constructed with the longitudinal axis parallelto the direction of flood flow.b. So far as practicable, structures shall be placed approximately on the same flood flowlines as those of adjoining structures.3. Accessory structures shall be elevated on fill or structurally dry floodproofed inaccordance with the FP-1 or FP-2 floodproofing classifications in the State Building Code.As an alternative, an accessory structure may be floodproofed to the FP-3 or FP-4floodproofing classification in the State Building Code provided the accessory structureconstitutes a minimal investment, does not exceed five hundred (500) square feet in size,and for a detached garage, the detached garage must be used solely for parking ofvehicles and limited storage. All floodproofed accessory structures must meet thefollowing additional standards, as appropriate:a. The structure must be adequately anchored to prevent flotation, collapse or lateralmovement of the structure and shall be designed to equalize hydrostatic flood forces onexterior walls; andLakeville Water Resources Management Plan Page 5-57

. Any mechanical and utility equipment in a structure must be elevated to or above theregulatory flood protection elevation or properly floodproofed.G. Storage Of Material And Equipment:1. The storage or processing of materials that are in time of flooding buoyant, flammable,explosive, or could be injurious to human, animal, or plant life, is prohibited.2. Storage of other material or equipment may be allowed if not subject to major damageby floods and firmly anchored to prevent flotation or readily movable from the areawithin the time available after flood warning.H. Garbage And Solid Waste Disposal: No conditional use permits for garbage and wastedisposal sites shall be issued for floodway areas. There shall be no further encroachmentupon the floodway at existing sites.I. Structural Works:1. Structural works for flood control that will change the course, current or cross sectionof protected wetlands or public waters shall be subject to the applicable provisions ofMinnesota statutes and review of the Minnesota Department of Natural Resources andthe Army Corps of Engineers community-wide structural works for flood controlintended to remove areas from the regulatory flood plain shall not be allowed in thefloodway.2. A levee, dike or floodwall constructed in the floodway shall not cause an increase to the100-year or regional flood and the technical analysis must assume equal conveyance orstorage loss on both sides of a stream. (Ord. 674, sec. 1, 7-17-2000)11-101-13: FF, FLOOD FRINGE DISTRICT:A. Permitted Uses:1. General farming, pasture, grazing, outdoor plant nurseries, horticulture, truck farming,forestry, sod farming, and wild crop harvesting.2. Industrial loading areas, parking areas, and airport landing strips.3. Private and public golf courses, tennis courts, driving ranges, archery ranges, picnicgrounds, boat launching ramps, swimming areas, parks, wildlife and nature preserves,game farms, fish hatcheries, shooting preserves, target ranges, trap and skeet ranges,hunting and fishing areas, and single or multiple purpose recreational trails, includingpedestrian bridges.4. Residential lawns, gardens, parking areas, and play areas.5. Public utilities, sanitary sewer, public water, storm sewer, and street improvements.B. Conditional Uses: The following are conditional uses in the flood plain districts providedthey are allowed in the base zoning districts (requires a conditional use permit and shall besubject to the standards, criteria and procedures specified in subsection C of this Section andSection 11-101-29 of this Chapter).1. Floodway Conditional Uses: Floodway conditional uses are subject to the sameconditions of subsection 11-101-11E of this Chapter.2. Residential Uses: Principal and accessory residential structures shall be constructed onfill with the lowest floor (including basement) at or above the regulatory flood protectionLakeville Water Resources Management Plan Page 5-58

elevation. The finished fill elevation shall be no more than one foot (1') below theregulatory flood protection elevation for the particular area and shall extend at suchelevation at least fifteen feet (15') beyond the limits of any structure or building erectedthereon. For detached residential accessory structures of no more than five hundred(500) square feet of gross floor area and representing minimal investment the fill shallextend at such elevation at least five feet (5') beyond the limits of said structure erectedthereon.3. Nonresidential Structures: Commercial, manufacturing, and industrial structures shallordinarily be elevated on fill so that their lowest floor (including basement) is at or abovethe regulatory flood protection elevation, but may where flood plain fill may result in anincrease in the regional flood elevation, change in the natural course of the flood plaindrainage or result in potential flooding of neighboring properties be floodproofed inaccordance with the State Building Code. Structures that are not elevated to above theregulatory flood protection elevation shall be floodproofed to FP-1 or FP-2 classificationas defined by the State Building Code. Structures floodproofed to FP-3 or FP-4classification shall not be permitted.C. Standards For Flood Fringe Uses:1. Damage Potential: The use shall have a low flood damage potential.2. Flood Flows: The use shall not obstruct flood flows or increase flood elevations andshall not involve structures, fill, obstructions, excavations or storage of materials orequipment.3. Residential Uses: Residences that do not have vehicular access at or above an elevationnot more than two feet (2') below the regulatory flood protection elevation shall not bepermitted unless granted a variance by the Board of Adjustment. In granting a variance,the Board shall specify limitations on the period of use or occupancy of the residence.4. Business Uses: Commercial structures generally must be constructed on fill with nofirst floor or basement floor below the flood protection elevation. Accessory land uses,such as yards, railroad tracks, and parking lots may be at lower elevations. However, apermit for such facilities to be used by the general public shall not be granted, in theabsence of a flood warning system, if the area is inundated to a depth greater than twofeet (2') or subject to flood velocities greater than four feet (4') per second upon theoccurrence of the regional flood.5. Manufacturing And Industrial Uses: Manufacturing and industrial buildings,structures and appurtenant works shall be projected to the flood protection elevation.Measures shall be taken to minimize interference with normal plant operations especiallyfor streams having protracted flood durations. Certain necessary land uses such as yardsand parking lots may be at lower elevations subject to requirements set out in subsectionC4 of this Section. In considering permit applications, the City Engineer shall give dueconsideration to needs of an industry whose business requires that it be located in floodplain areas.6. Waste Treatment And Waste Disposal:a. No new construction, addition, or modification to existing waste treatment facilitiesshall be permitted within the flood fringe unless emergency plans and procedures foraction to be taken in the event of flooding are prepared, filed with, and approved by theLakeville Water Resources Management Plan Page 5-59

Minnesota Pollution Control Agency. The emergency plans and procedures must providefor measures to prevent introduction of any pollutant or toxic material into the floodwaters.b. There shall be no disposal of garbage or solid waste materials within flood fringe areasexcept upon issuance of a conditional use permit at sites approved by the MinnesotaPollution Control Agency and subject to the requirements of Chapter 4 of this Title.7. Flood Control Works: Establishment of flood control works shall be subject to theapplicable provisions of Minnesota statutes and review of the Minnesota Department ofNatural Resources and the Army Corps of Engineers and Chapter 4 of this Title.a. The minimum height and design of any dikes, levees, floodwalls, or similar structuralworks shall be based upon the flood profile of the regional flood defined between thestructures subject to the following:(1) For urban areas, the minimum height and design of structure works shall be atleast three feet (3') above the elevation of the regional flood or at the elevation of thestandard protect flood, whichever is greater.(2) Modifications and additions to existing structural works shall assure that thework will provide a means of decreasing the flood damage potential in the area. Anyexisting structural work which potentially threatens public health or safety shall bemodified or reconstructed in order to meet the standards contained herein within aperiod of one year of the effective date hereof.b. Flood protection elevations and floodway limits which reflect proposed measures forflood control shall not be effective until such measures are constructed and operativeunless the proposed measures will increase flood heights, in which event, the regulatoryflood protection elevations and flood plain limits shall reflect the anticipated increases.c. Detailed plans shall be submitted to the City Engineer for any new developmentsplaced on the flood plain landward from the dikes and levees. The plans must provide forponding areas or other measures to protect against flooding from internal drainage.8. Fill For Construction: Fill shall be adequately compacted and the slopes shall beprotected by the use of riprap, vegetative cover or other acceptable method. The FederalEmergency Management Agency (FEMA) has established criteria for removing thespecial flood hazard area designation for certain structures properly elevated on fillabove the 100-year flood elevation. FEMAs requirements incorporate specific fillcompaction and side slope protection standards for multi-structure or multi-lotdevelopments. These standards must be investigated prior to the initiation of sitepreparation if a change of special flood hazard area designation will be requested.9. Structural Floodproofing Standards: Alternative elevation methods other than the useof fill may be utilized to elevate a commercial and industrial structure's lowest floorabove the regulatory flood protection elevation. These alternative methods may includethe use of stilts, pilings, parallel walls, etc., or above grade, enclosed areas such ascrawlspaces or tuck under garages. The base or floor of an enclosed area shall beconsidered above grade and not a structure's basement or lowest floor if: a) the enclosedarea is above grade on at least one side of the structure; b) is designed to internally floodand is constructed with flood resistant materials; and c) is used solely for parking ofvehicles, building access or storage. The above noted alternative elevation methods aresubject to the following additional standards:Lakeville Water Resources Management Plan Page 5-60

a. Design And Certification: The structure's design and as-built condition must be certified bya registered professional engineer or architect as being in compliance with the general designstandards of the State Building Code and, specifically, that all electrical, heating, ventilation,plumbing and air-conditioning equipment and other service facilities must be at or above theregulatory flood protection elevation or be designed to prevent flood water from entering oraccumulating within these components during times of flooding.b. Specific Standards For Above Grade, Enclosed Areas: Above grade, fully enclosed areassuch as crawlspaces or tuck under garages must be designed to internally flood and thedesign plans must stipulate:(1) The minimum area of openings in the walls where internal flooding is to be used as afloodproofing technique. When openings are placed in a structure's walls to provide forentry of flood waters to equalize pressures, the bottom of all openings shall be no higherthan one foot (1') above grade. Openings may be equipped with screens, louvers, valves,or other coverings or devices provided that they permit the automatic entry and exit offlood waters.(2) That the enclosed area will be constructed of flood resistant materials in accordancewith the FP-3 or FP-4 classifications in the State Building Code and shall be used solelyfor building access, parking of vehicles or storage.c. Basements: "Basements", as defined in Section 11-2-3 of this Title, shall be subject to thefollowing:(1) Residential basement construction shall not be allowed below the regulatory floodprotection elevation.(2) Nonresidential basements may be allowed below the regulatory flood protectionelevation provided the basement is structurally dry floodproofed in accordance withsubsection C9d of this Section.d. Nonresidential Structures: All areas of nonresidential structures, including basements tobe placed below the regulatory flood protection elevation, shall be floodproofed inaccordance with the structurally dry floodproofing classifications in the State Building Codeand this shall require making the structure watertight with the walls substantiallyimpermeable to the passage of water and with structural components having the capability ofresisting hydrostatic and hydrodynamic loads and the effects of buoyancy. Structuresfloodproofed to the FP-3 or FP-4 classification shall not be permitted.10. Erosion Control: When at any one time more than one thousand (1,000) cubic yards offill or other similar material is located on a parcel for such activities as on-site storage,landscaping, sand and gravel operations, landfills, roads, dredge spoil disposal orconstruction of flood control works, an erosion/sedimentation control plan must besubmitted unless the respective flood plain area falls within a designated ShorelandOverlay District and shoreland regulations will be applied. In the absence of a Stateapproved Shoreland Ordinance, the plan must clearly specify methods to be used tostabilize the fill on-site for a flood event at a minimum of the 100-year or regional floodevent. The plan must be prepared and certified by a registered professional engineering orother qualified individual acceptable to the governing body. The plan may incorporatealternative procedures for removal of the material from the flood plain if adequate floodwarning time exists.11. Storage Of Materials And Equipment:Lakeville Water Resources Management Plan Page 5-61

a. The storage or processing of materials that are, in the time of flooding, flammable,explosive, or potentially injurious to human, animal, or plant life is prohibited.b. Storage of other materials or equipment may be allowed if readily removable from the areawithin the time available after a flood warning and in accordance with a plan approved by thegoverning body.c. The provisions of subsection C5 of this Section shall also apply. (Ord. 674, sec. 1, 7-17-2000)11-101-15: GFD, GENERAL FLOOD PLAIN DISTRICT:A. Permitted Uses: The uses listed as permitted uses in Section 11-101-11 of this Chapter arepermitted uses in the General Flood Plain District.B. Conditional Uses: All other uses shall be subject to the floodway/flood fringe evaluationcriteria pursuant to subsection 11-101-29A of this Chapter. Section 11-101-11 of this Chaptershall apply if the proposed use is in the Floodway District and Section 11-101-13 of thisChapter shall apply if the proposed use is in the Flood Fringe District. (Ord. 674, sec. 1, 7-17-2000)11-101-17: SUBDIVISIONS:A. Review Criteria: No land shall be subdivided which is unsuitable for the reason offlooding, inadequate drainage, water supply or sewage treatment facilities. All lots within theflood plain districts shall contain a building site at or above the regulatory flood protectionelevation. All subdivisions shall have water and sewage treatment facilities that comply withthe provisions of this Title and have road access both to the subdivision and to the individualbuilding sites no lower than two feet (2') below the regulatory flood protection elevation andthe required elevation of all access roads shall be clearly labeled on all required subdivisiondrawings and platting documents.B. Removal Of Special Flood Hazard Area Designation: FEMA has established criteria forremoving the special flood hazard area designation for certain structures properly elevatedon fill above the 100-year flood elevation. FEMA requirements incorporate specific fillcompaction and side slope protection standards for multi-structure or multi-lotdevelopments. (Ord. 674, sec. 1, 7-17-2000)11-101-19: PUBLIC UTILITIES, RAILROADS, ROADS, AND BRIDGES:A. Public Utilities: All public utilities and facilities such as gas, electrical, sewer, and watersupply systems to be located in the flood plain shall be floodproofed in accordance with theState Building Code or elevated to above the regulatory flood protection elevation.B. Public Transportation Facilities: Railroad tracks, roads, and bridges to be located withinthe FP Floodway District shall comply with subsection 11-101-11E of this Chapter. All railroadtracks, roads, bridges, and major transportation facilities must be constructed at or above theregulatory flood protection elevation where failure or interruption of these transportationfacilities would result in danger to the public health or safety or where such facilities areessential to the orderly functioning of the area. Minor or auxiliary roads or minor railroadsLakeville Water Resources Management Plan Page 5-62

may be constructed at an elevation two feet (2') below the regulatory flood protectionelevation where failure or interruption of transportation services would not endanger thepublic health or safety.C. On-Site Sewage Treatment And Water Supply Systems: Where public utilities are notprovided: 1) on-site water supply systems must be designed to minimize or eliminateinfiltration of flood waters into the systems; and 2) new or replacement on-site sewagetreatment systems must be designed to minimize or eliminate infiltration of flood waters intothe systems and discharges from the systems into flood waters and they shall not be subjectto impairment or contamination during times of flooding. Any sewage treatment systemdesigned in accordance with the State's current Statewide standards for on-site sewagetreatment systems shall be determined to be in compliance with this Chapter. (Ord. 674, sec.1, 7-17-2000)11-101-21: MANUFACTURED HOMES AND MANUFACTURED HOME PARKS ANDPLACEMENT OF TRAVEL TRAILERS AND TRAVEL VEHICLES:A. Restrictions: New manufactured home parks and expansions to existing manufacturedhome parks shall be subject to the provisions placed on subdivisions by Section 11-101-17 ofthis Chapter.B. Elevation And Anchoring:1. The placement of new or replacement manufactured homes in existing manufacturedhome parks or on individual lots of record that are located in the AE, A99, AH and AOflood zones on the City's current FIRM Map, as may be amended, will be treated as a newstructure and may be placed only if elevated in compliance with subsection 11-101-13B ofthis Chapter.2. All manufactured homes must be securely anchored to an adequately anchoredfoundation system that resists flotation, collapse and lateral movement. Methods ofanchoring may include, but are not limited to, use of over the top or frame ties to groundanchors. This requirement is in addition to applicable State or local anchoringrequirements for resisting wind forces.C. Travel Trailers: Travel trailers and travel vehicles that do not meet the exemption criteriaspecified in subsection C1 of this Section shall be subject to the provisions of this Chapterand as specifically spelled out in subsections C3 and C4 of this Section.1. Exemptions: Travel trailers and travel vehicles are exempt from the provisions of thisChapter if they are placed in any of the areas listed in subsection C2 of this Section, andfurther they meet the following criteria:a. Have current licenses required for highway use.b. Are highway ready, meaning on wheels or the internal jacking system, are attached tothe site only by quick disconnect type utilities commonly used in campgrounds andtrailer parks and the travel trailer/travel vehicle has no permanent structural typeadditions attached to it.2. Areas Exempted For Placement Of Travel/Recreational Vehicles:a. Individual lots or parcels of record.Lakeville Water Resources Management Plan Page 5-63

. Existing commercial recreational vehicle parks or campgrounds.c. Existing condominium type associations.3. Development: Travel trailers and travel vehicles exempted in subsection C1 of thisSection, lose this exemption when development occurs on the parcel exceeding onethousand dollars ($1,000.00) for a structural addition to the travel trailer/travel vehicleor an accessory structure such as a garage or storage building. The travel trailer/travelvehicle and all additions and accessory structures will then be treated as a new structureand shall be subject to the elevation/floodproofing requirements and the use of landrestrictions specified in Sections 11-101-11 and 11-101-17 of this Chapter.4. New Parks: New commercial travel trailer or travel vehicle parks or campgrounds andnew residential type subdivisions and condominium associations and the expansion ofany existing similar use exceeding five (5) units or dwelling sites shall be subject to thefollowing:a. Any new or replacement travel trailer or travel vehicle will be allowed in the FF, FloodFringe District or GFD, General Flood Plain Districts, provided said trailer or vehicle andits contents are placed on fill above the regulatory flood protection elevation and properelevated road access to the site exists in accordance with subsection 11-101-11E of thisChapter. No fill placed in the floodway to meet the requirements of this Chapter shallincrease flood stages of the 100-year or regional flood.b. All new or replacement travel trailers or travel vehicles not meeting the criteria ofsubsection C4a of this Section may, as an alternative, be allowed as a conditional use if inaccordance with the following provisions and the provisions of Section 11-101-29 of thisChapter. The applicant must submit an emergency plan for the safe evacuation of allvehicles and people during the 100-year flood. Said plan shall be prepared by a registeredengineer or other qualified individual and shall demonstrate that adequate time andpersonnel exist to carry out the evacuation. All attendant sewage and water facilities fornew or replacement travel trailers or other recreational vehicles must be protected orconstructed so as to not be impaired or contaminated during times of flooding inaccordance with subsection 11-101-19C of this Chapter. (Ord. 674, sec. 1, 7-17-2000)11-101-23: ADMINISTRATION:A. Permit Requirements: A permit issued by the Zoning Administrator in conformity withthe provisions of this Title shall be secured prior to the erection, addition, or alteration ofany building, structure, or portion thereof; prior to the use or change of use of a building,structure or land; prior to the change or extension of a nonconforming use; and prior to theplacement of fill, excavation of materials, or the storage of materials or equipment within theflood plain.B. Application And Fee: A use permit shall be applied for from the Zoning Administrator.Said application shall be made in duplicate and shall include the following where applicable:plans in duplicate drawn to scale, showing the nature, location, dimensions, and elevationsof the lot; existing or proposed structures, fill, or storage of materials; and the location of theforegoing in relation to the stream channel. An application fee and cash escrow. Theapplication fee amount will be in accordance with City resolution and shall be required foreach use permit.Lakeville Water Resources Management Plan Page 5-64

C. Determination: Within ten (10) days after the application for a use permit, the CityEngineer shall determine whether the change, modification, or alteration conforms to therequirements of all applicable City and State regulations and ordinances. This time limit fordetermination of acceptability shall be automatically extended should referral to, or permitfrom, another governmental jurisdiction be required. The applicant shall be advised inwriting of the City Engineer's determination and findings and if acceptable, a use permitshall be granted.D. Security:1. Upon approval of a use permit, the City shall be provided with financial security priorto the issuing of building permits or initiation of work on the proposed improvements ordevelopment. Said security shall guarantee conformance and compliance with theconditions of the use permit and the codes and ordinances of the City.2. The financial security shall be in the amount of the City Engineer's and/or CityBuilding Official's estimated costs of labor and materials for the proposed improvementsor development.3. The City shall hold the security until completion of the proposed improvements ordevelopment at which time a certificate of occupancy indicating compliance with the usepermit and codes and ordinances of the City may be issued by the City Building Officialand said security released. The applicant shall be required to submit certification by aregistered professional engineer, registered architect, or registered land surveyor that thefinished fill and building elevations were accomplished in compliance with the provisionsof this Chapter. Floodproofing measures shall be certified by a registered professionalengineer or registered architect.E. Compliance: No new structure or land shall hereafter be used and no structure shall belocated, extended, converted, or structurally altered without full compliance with the termsof this Title and other applicable regulations which apply to uses within the jurisdiction ofthis Title. Within the FW, Floodway; FF, Flood Fringe; and GFD, General Flood PlainDistricts, all uses not listed as permitted uses or conditional uses in Sections 11-101-11 and11-101-15 of this Chapter, shall be prohibited. In addition:1. New manufactured homes, replacement manufactured homes and certain traveltrailers and travel vehicles are subject to the general provisions of this Title andspecifically Section 11-101-21 of this Chapter.2. Modifications, additions, structural alterations or repair after damage to existingnonconforming structures and nonconforming uses of structures or land are regulated bythe general provisions of this Title and specifically, Section 11-101-31 of this Chapter.3. As-built elevations for elevated or floodproofed structures must be certified by groundsurveys and floodproofing techniques must be designed and certified by a registeredprofessional engineer or architect as specified in the general provisions of this Chapterand specifically as stated in subsection H of this Section.F. Certificate Of Zoning Compliance For New, Altered, Or Nonconforming Use: It shall beunlawful to use, occupy, or permit the use or occupancy of any building or premises or partLakeville Water Resources Management Plan Page 5-65

thereof hereafter created, erected, changed, converted, altered, or enlarged in its use orstructure until a certificate of zoning compliance shall have been issued by the ZoningAdministrator stating that the use of the building or land conforms to the requirements ofthis Title.G. Construction And Use To Be As Provided On Applications, Plans, Permits, Variances AndCertificates Of Zoning Compliance: Permits, conditional use permits, or certificates of zoningcompliance issued on the basis of approved plans and applications authorize only the use,arrangement, and construction set forth in such approved plans and applications, and noother use, arrangement, or construction. Any use, arrangement, or construction at variancewith that authorized shall be deemed a violation of this Chapter, and punishable as providedby Chapter 10 of this Title.H. Certification: The applicant shall be required to submit certification by a registeredprofessional engineer, registered architect, or registered land surveyor that the finished filland building elevations were accomplished in compliance with the provisions of this Chapter.Floodproofing measures shall be certified by a registered professional engineer or registeredarchitect.I. Record Of First Floor Elevation: The Zoning Administrator shall maintain a record of theelevation of the lowest floor (including basement) of all new structures and alterations oradditions to existing structures in the flood plain. The Zoning Administrator shall alsomaintain a record of the elevation to which structures and/or alteration additions tostructures are floodproofed. (Ord. 674, sec. 1, 7-17-2000)11-101-25: AMENDMENTS AND VARIANCES:A. In addition to the procedures and requirements for amendments and variances asestablished in Chapters 3 and 6 of this Title, the commissioner of Natural Resources shall begiven at minimum ten (10) days notice of any public hearing, and a review and written reportmust be obtained from the Minnesota Department of Natural Resources and any othergovernmental body or commission having jurisdiction for such changes, additions ormodifications affecting an FP, Flood Plain Overlay District. The commissioner of NaturalResources shall be advised in writing of all decisions made regarding variances andamendments.B. No variance or amendment shall have the effect of allowing a prohibited use within an FPDistrict, permit a lesser degree of flood protection than the established flood protectionelevation, and/or permit standards lower than those required under applicable State law.(Ord. 674, sec. 1, 7-17-2000)11-101-27: FLOOD INSURANCE NOTICE AND RECORD KEEPING:The Zoning Administrator shall notify the applicant for a variance that: a) the issuance of avariance to construct a structure below the base flood level will result in increased premium ratesfor flood insurance, and b) such construction below the 100-year or regional flood level increasesrisks to life and property. Such notification shall be maintained with a record of all varianceLakeville Water Resources Management Plan Page 5-66

actions. A community shall maintain a record of all variance actions, including justification fortheir issuance, and report such variances issued in its annual or biannual report submitted to theadministrator of the National Flood Insurance Program. (Ord. 674, sec. 1, 7-17-2000)11-101-29: CONDITIONAL USES:Conditional uses require a conditional use permit based upon procedures set forth in, andregulated by, Chapter 4 of this Title. In addition, the City Engineer shall determine whether theproposed conditional use location is within a floodway or flood fringe area by computing thefloodway necessary to convey or store the regional flood without increasing flood stages morethan 0.5 feet. A lesser stage increase than 0.5 feet shall be required if, as a result of the additionalstage increase, increased flood damages would result. An equal degree of encroachment on bothsides of the stream within the reach shall be assumed in computing floodway boundaries. Uponsuch determination, the applicable conditions, provisions and restrictions shall be imposed. Thecommissioner of Natural Resources shall be given at minimum ten (10) days' notice of therequired public hearing and shall be advised in writing of decisions made concerning anyconditional use.A. Procedures And Standards For Evaluating Proposed Conditional Uses: Upon receipt of anapplication for a conditional use permit for a use within the FP Flood Plain District, theapplicant shall be required to furnish such of the following information as is deemednecessary for the determination of the regulatory flood protection elevation and whether theproposed use is in the FW, Floodway or the FF, Flood Fringe District:1. A typical valley cross section showing the channel of the stream, elevation of land areasadjoining each side of the channel, cross sectional areas to be occupied by the proposeddevelopment, and high water information.2. Plan (surface view) showing the nature, locations, dimensions, and elevation of the lot,contours of the ground, fill; storage of materials; floodproofing measures; thearrangement of all proposed and existing structures on the site; locations and elevationsof streets; existing and proposed utilities, septic tanks or water wells; existing land usesand vegetation upstream and downstream; soil type, and the relationship of the above tothe location of the channel.3. Profile showing the slope of the bottom of the channel or flow line of the stream for atleast five hundred feet (500') in either direction from the proposed development.B. Supplementary Considerations: In acting upon the conditional use application, thegoverning body shall consider all relevant factors specified in subsection 11-4-3E of this Titlein addition to:1. The danger to life and property due to increased flood heights or velocities caused byencroachments.2. The danger that materials may be swept onto other lands or downstream to the injuryof others or they may block bridges, culverts, or other hydraulic structures.3. The water supply and sanitation systems and the ability of these systems to preventdisease, contamination, and unsanitary conditions.4. The susceptibility of the proposed facility and its contents to flood damage and theeffect of such damage on the individual owner.Lakeville Water Resources Management Plan Page 5-67

5. The importance of the services provided by the proposed facility to the community.6. The requirements of the facility for a waterfront location.7. The availability of alternative locations not subject to flooding for the proposed use.8. The compatibility of the proposed use with existing development and developmentanticipated in the foreseeable future.9. The relationship of the proposed use to the Comprehensive Plan and flood plainmanagement program for the area.10. The safety of access to the property in times of flood for ordinary and emergencyvehicles.11. The expected heights, velocity, duration, rate of rise, and sediment transport of theflood waters expected at the site.12. Such other factors which are relevant to the purposes of this Chapter.C. Conditions Attached To Conditional Use Permits: Upon consideration of the factors listedabove and the purposes of this Chapter, the governing body may attach such conditions tothe granting of conditional use permits, as it deems necessary to fulfill the purposes of thisChapter. Such conditions may include, but are not limited to, the following:1. Modification of waste treatment and water supply facilities.2. Limitations on period of use, occupancy, and operation.3. Imposition of operational controls, sureties, and deed restrictions.4. Requirements for construction of channel modifications, compensatory storage, dikes,levees, and other protective measures.5. Floodproofing measures, in accordance with the State Building Code and this Chapter.The applicant shall submit a plan or document certified by a registered professionalengineer or architect that the floodproofing measures are consistent with the regulatoryflood protection elevation and associated flood factors for the particular area. (Ord. 674,sec. 1, 7-17-2000)11-101-31: AMENDMENTS:A. The flood plain designation on the Official Zoning Map shall not be removed from floodplain areas unless it can be shown that the designation is in error or that the area has beenfilled to or above the elevation of the regional flood and is contiguous to lands outside theflood plain. Special exceptions to this rule may be permitted by the commissioner of NaturalResources if he determines that, through other measures, lands are adequately protected forthe intended use.B. All amendments to this Chapter, including amendments to the Official Zoning Map, mustbe submitted to and approved by the Commission of Natural Resources prior to adoption.Changes in the Official Zoning Map must meet the FEMA technical conditions and criteriaand must receive prior FEMA approval before adoption. The commissioner of NaturalResources must be given ten (10) days' written notice of all hearings to consider anamendment to this Chapter and said notice shall include a draft of the amendment ortechnical study under consideration. (Ord. 674, sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-68

5.7LAKEVILLE ORDINANCE 10-4-5: EROSION AND SEDIMENTCONTROLA. The development shall conform to the natural limitations presented by topography andsoil so as to create the least potential for soil erosion.B. Erosion and siltation control measures shall be coordinated with the different stages ofconstruction. Appropriate control measures shall be installed prior to development whennecessary to control erosion.C. Land shall be developed in increments of workable size such that adequate erosion andsiltation controls can be provided as construction progresses. The smallest practical area ofland shall be exposed at any one period of time.D. When soil is exposed, the exposure shall be for the shortest feasible period of time, asspecified in the development agreement.E. Where the topsoil is removed, sufficient topsoil shall be set aside for respreading over thedeveloped area. Topsoil shall be restored or provided to a minimum depth of four inches (4")and shall be of a quality at least equal to the soil quality prior to development.F. Natural vegetation shall be protected wherever practical.G. Runoff water shall be diverted to a sedimentation basin before being allowed to enter thenatural drainage system.H. The developer shall comply with current City specifications for erosion and sedimentcontrol, including any specifications or design standards specifically adopted to provideadditional protection to various categories of water bodies as defined in Section 10-4-7 ofthis Chapter.I. Development shall comply with and follow all best management practices for erosion andsedimentation control as specified in the MPCA publication "Protecting Water Quality inUrban Areas", as may be amended. (Ord. 673, sec. 1, 7-17-2000).Lakeville Water Resources Management Plan Page 5-69

5.8 LAKEVILLE ORDINANCE 10-4-6: STORM DRAINAGEAll subdivision design shall incorporate adequate provisions for stormwater runoff consistentwith the Lakeville Stormwater Management Plan (SWMP, superseded by the 2008 WRMP) asamended, and with established City policies, and conform to the following standards;A. Plan Required: The proposed provisions for stormwater runoff shall be documented in arunoff water management plan, prepared by a Minnesota licensed engineer to the minimumstandards described in subsection B of this Section.B. Minimum Standards For Runoff Water Management Plans: A runoff water managementplan shall include the following items:1. A map containing a delineation of the sub-watershed contributing runoff from off-site,and proposed and existing sub-watersheds on-site. The delineation shall conform to thenomenclature of the SWMP (WRMP) and shall indicate any significant departures fromthe watershed delineation of the SWMP (WRMP).2. Delineation of existing on-site "wetlands", as defined in the Wetland Conservation Act,lakes, streams, shoreland, and/or flood plain areas.3. For water bodies and channels, a listing of normal (run-out) and calculated 10-yearand 100-year elevations on-site for both existing and proposed conditions.4. Stormwater runoff volumes and rates for existing and proposed conditions.5. All hydrologic and hydraulic computations completed to design the proposedstormwater management facilities. Reservoir routing procedures and critical durationrunoff events shall be used for design of water storage areas and outlets.6. A checklist of best management practices to demonstrate that, to the maximum extentpractical, the plan has incorporated the structural and nonstructural best managementpractices described in the book "Protecting Water Quality in Urban Areas", published bythe Minnesota Pollution Control Agency or the applicable publications.7. A grading plan identifying stormwater overflow routes along streets or drainageeasements designed to protect structures from damage due to:a. Storms in excess of the design storm, orb. Clogging, collapse or other failure of the primary drainage facilities.8. An assessment of the potential for construction or contribution to regional detentionbasins, as opposed to the construction of on-site basins. The SWMP (WRMP) identifiespotential regional pond areas for control of rate and nutrient loading. The followingcriteria shall be used to determine whether on-site storage is required for within thesubdivision:a. If the runoff water management plan indicates construction or enlargement of astorage site or water quality storage in a wetland or other water body, the facility or itsequivalent shall be constructed to meet the goals of the SWMP (WRMP).b. If a proposed subdivision will be directly tributary to a water body without interveningdetention storage, additional on-site pond construction for water quality treatment willbe required if the water body is in one of the following classifications:Lakeville Water Resources Management Plan Page 5-70

Category I: Water bodies supporting direct body contact recreation such as swimming,skin diving or water skiing.Category Ia: Water bodies capable of supporting a trout fishery.Category II: Water bodies supporting noncontact recreational activities such assailboating, motor boating, canoeing and fishing.Category III: Water bodies supporting aesthetic viewing and wildlife habitat functions,providing open space, scenic vistas and opportunities for wildlife observation or warmwater fishing.Category IV: Nutrient Traps. Water bodies functioning mainly to reduce downstreamloading of phosphorus and other pollutants.c. If a proposed subdivision is indirectly tributary to a Category I, II or III water body andintervening regional detention storage is inadequate, in the opinion of City staff, to meetthe water quality goals for downstream water bodies as described in the SWMP (WRMP),additional on-site pond construction will be required to meet these goals.d. If a proposed subdivision will increase rates of runoff and where downstreamstormwater storage or conveyance facilities are inadequate to protect downstreamriparian owners from effects of these increases, then on-site stormwater storage must beconstructed to restrict stormwater rates to the predevelopment rates.9. Where on-site water quality detention basins are required, copies of the calculationsdetermining the design of the basins. The size and design considerations will bedependent on the receiving water body's water quality category, the imperviousness ofthe development and the degree to which on-site infiltration of runoff is encouraged.Design of on-site detention basins, as described in the site's runoff water managementplan, shall incorporate recommendations from the Nationwide Urban Runoff Program(NURP) and "Protecting Water Quality in Urban Areas", published by the MinnesotaPollution Control Agency, as adopted by the City, or the applicable publications, asadopted by the City. The following design considerations are required for on-site waterquality detention basins based on the receiving water's water quality category. Thesedesigns include permanent detention for water quality treatment; extended detentiondesigns may be substituted provided that they provide treatment equivalent to therequirements below:a. Basins Tributary To Category I Water Bodies:(1) A permanent pool (dead storage) volume below the normal outlet shall be greaterthan or equal to the runoff from a two and one-half inch (2.5") 24-hour storm overthe entire contributing drainage area assuming full development.(2) A permanent pool average depth (basin volume/basin area) which shall be greaterthan four feet (4'), with a maximum depth of less than ten feet (10').(3) An emergency spillway (emergency outlet) adequate to control the 100-yearfrequency critical duration rainfall event.(4) Basin side slopes above the normal water level should be no steeper than three toone (3:1) when possible, and preferably flatter. A basin shelf with a minimum widthof ten feet (10') and a maximum slope of ten to one (10:1) below the normal waterlevel is recommended to enhance wildlife habitat, reduce potential safety hazards,and improve access for long term maintenance.Lakeville Water Resources Management Plan Page 5-71

(5) To prevent short circuiting, the distance between the major inlets and normaloutlet shall be maximized.(6) A flood pool (temporary storage) volume above the principal outlet spillway shallbe adequate so that the peak discharge rate from the 10- and 100-year frequencycritical duration storm is not greater than the peak discharge for a similar storm andpredevelopment watershed conditions. (Ord. 673, sec. 1, 7-17-2000)(7) Extended detention of runoff from the more frequent (1-year to 5-year) stormsshall be achieved through a principal spillway design which shall include a perforatedvertical riser, a small orifice outlet or a compound weir. The spillway must beconstructed of a limited maintenance material. The use of treated, or naturally decayresistant timber shall not be allowed. (Ord. 731, sec. 21, 3-17-2003)(8) Effective energy dissipation devices which reduce outlet velocities to four feet (4')per second or less shall consist of riprap, stilling pools or other such measures toprevent erosion at all storm water outfalls into the basin and at the detention basinoutlet. (Ord. 673, sec. 1, 7-17-2000)(9) Trash and floatable debris skimming devices shall be placed on the outlet of all onsite detention basins to provide treatment up to the critical duration 10-year stormevent. These devices can consist of baffled weirs, submerged inlets or other suchmeasures capable of restricting the overflow of floatable materials, including litter, oiland grease. The skimming device must be constructed of a limited maintenancematerial. The use of treated, or naturally decay resistant timber shall not be allowed.Computations for the design of such devices shall be included. The maximum velocitythrough the skimming device shall be less than one foot (1') per second (fps) on the 2-year 24-hour event. (Ord. 731, sec. 22, 3-17-2003)(10) For purposes of erosion control, vegetation protection and wildlife habitatenhancement, the 10-year flood level of the basin shall be no more than two feet (2')above the normal level of the basin.b. Basins Tributary To Category Ia Water Bodies: Basins constructed adjacent ortributary by surface or subsurface discharge to a category Ia water body shall also meetthe following design standards:(1) Infiltration areas are required for newly platted areas with volume sufficient tocontain one and one-half inch (1.5") of runoff from all impervious surfaces, includingrooftops, for existing and future phases of development, and have average depth suchthat this volume infiltrates within seventy two (72) hours. The infiltration rate can bedetermined via direct measurement with a soil percolation test, other permeabilitytest, or by estimation using the conservative end of the range given in the DakotaCounty soil survey for the soil type as mapped there at the discretion of the cityengineer.(2) Where soil permeability does not meet the above criteria, additional designconsiderations to enhance the rate of pond seepage such as a drain tile outlet or othermeasures may be required by the city engineer.(3) Infiltration depressions shall not be lined nor shall mining of native material beallowed.Lakeville Water Resources Management Plan Page 5-72

(4) Revegetation on the infiltration area bottoms shall consist in the majority of planttypes which can tolerate inundated condition for periods of days and have rootdepths in excess of eighteen inches (18").(5) The lowest topographical point in an infiltration depression should be at least twofeet (2') above the average water table in that location.(6) Ponding areas shall be set back a distance of seventy five feet (75') from thestream centerline to the edge of a pond. In the case of distributed infiltration areas,this setback may be varied. Where the storm water design is such that fifty percent(50%) of the infiltration area volume is beyond one hundred feet (100') from thechannel centerline, no setback is required.(7) Effective energy dissipation devices which reduce outlet velocities to four feet (4')per second or less shall consist of riprap, stilling pools or other such measures toprevent erosion at all storm water outfalls into the basin and at the detention basinoutlet.c. Basins Tributary To Category II Water Bodies:(1) A permanent pool (dead storage) volume below the normal outlet shall be greaterthan or equal to the runoff from a two inch (2") 24-hour storm over the entirecontributing drainage area assuming full development.(2) All other requirements as listed in subsections B9a(2) through B9a(10) of thissection for categories I and Ia water bodies.d. Basins Tributary To Category III Water Bodies:(1) A permanent pool (dead storage) volume below the normal outlet shall be greaterthan or equal to the runoff from a one and one-half inch (1.5") 24-hour storm overthe entire contributing drainage area assuming full development.(2) All other requirements as listed in subsections B9a(2) through B9a(10) of thissection for categories I and Ia water bodies.e. Basins Tributary To Category IV Water Bodies:(1) Any practical measures needed to maintain the function and character of thecategory IV water body. (Ord. 673, sec. 1, 7-17-2000)f. Basins Tributary To Wetlands:(1) Sedimentation capacity capable of protecting the wetland from filling due to waterborne silts and sand. Where feasible, appropriately sized in-line treatment capable ofbeing cleaned via manholes shall be preferred. (Ord. 731, sec. 23, 3-17-2003)(2) All other requirements as listed in subsections B9a(2) through B9a(10) of thissection for category I water bodies. (Ord. 673, sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-73

5.9 LAKEVILLE ORDINANCE 10-4-11: TREE PRESERVATIONThe following process for preserving significant trees shall be required of subdividers and homebuilders. Subdividers shall preserve, where feasible, all healthy trees of significant value even ifthe trees are less than six inches (6") in diameter.A. Definitions: The following words and terms, whenever they occur in this section, are definedas follows:DIAMETER: The measurement of a tree's trunk measured four and one-half feet (4.5') abovethe ground.DRIP LINE: The farthest distance away from the trunk of a tree that rain or dew will falldirectly to the ground from the leaves or branches of the tree or one foot (1') per one inch (1")of diameter, whichever is greater.SIGNIFICANT TREE: A healthy tree measuring six inches (6") in diameter or greater.TREE CERTIFICATION: A certified inventory of trees on the site after work is completelisting all trees and their final disposition, which is signed by a licensed forester or landscapearchitect.TREE PRESERVATION PLAN: A plan and inventory certified by a forester or landscapearchitect indicating all of the significant trees and their locations in the proposeddevelopment or on the lot. The tree preservation plan shall include the size, species, tagnumbers, and location of all significant trees proposed to be saved and removed on the areaof development, and the measures proposed to protect the significant trees to be saved.TREE PROTECTION: Snow fencing or polyethylene laminar safety netting placed at the dripline of the significant trees to be preserved. The tree protection measures shall be shown ontree preservation plan drawings and remain in place until all grading and constructionactivity is terminated.B. Subdividers:1. Subdividers shall:a. Prepare a tree preservation plan superimposed on the grading plan.b. Ensure the tree preservation plan is followed during the plan development (massgrading).c. Submit a five hundred dollar ($500.00) security for the preparation of individual lottree preservation plans for each mass graded lot with at least one significant tree to besaved and for each custom graded lot with at least one significant tree and a onethousand dollar ($1,000.00) security per lot for tree preservation requirements. Thesecurity will be included in the development contract.2. The tree preservation plan must be certified by a forester or landscape architect. Theforester or landscape architect shall indicate on the plan the following items:a. Mass graded areas and proposed grades.b. Custom graded lots.c. Size, species, tag numbers, and location of all significant trees.Lakeville Water Resources Management Plan Page 5-74

d. Identification of all significant trees proposed to be saved and significant treesproposed to be removed.e. Measures proposed to protect significant trees shall include, but are not limited to:(1) Installation of snow fencing or polyethylene laminar safety netting at the drip line.(2) Placing fill against the trunk of the tree, on the root crown, and under the dripline of the tree shall be prohibited.(3) Installation of erosion control measures.(4) Prevention of change in soil chemistry due to concrete washout and leakage orspillage of toxic materials such as fuels or paints.(5) Pruning of oak trees must not take place from April 15 through July 1. Ifwounding of oak trees occurs, a nontoxic tree wound dressing must be appliedimmediately. Excavators must have a nontoxic tree wound dressing with them on thedevelopment site. (Ord. 673, sec. 1, 7-17-2000)3. During preliminary plat review, the tree preservation plan will be reviewed according tothe best available layout to preserve significant trees and the efforts of the subdivider tomitigate damage to significant trees. If two (2) trees are preserved on each lot (preferably thefront yard of the lot), the landscape plan requirements of two (2) 2 1/2-inch caliper trees arewaived. (Ord. 731, sec. 24, 3-17-2003)4. The subdivider shall provide a financial guarantee as part of the development contract toguarantee replacement of all significant trees which were to have been saved but wereactually destroyed or damaged. A financial security for each mass graded lot with at least onesignificant tree to be saved and a financial security for each custom graded lot with at leastone significant tree shall be provided as part of the development contract to ensure treeprotection. The financial security, generally one thousand dollars ($1,000.00) per lot, will bedetermined by the community and economic development department based on the numberand size of trees to be saved.5. After mass grading has been completed and streets and utilities installed, the forester orlandscape architect shall:a. Certify in writing to the city the status of all trees indicated as save trees in theapproved plan.b. Certify in writing to the city whether tree protection measures were installed.c. Certify the status of any remove designated trees that were saved.6. If a significant tree indicated to be saved on the tree preservation plan is destroyed ordamaged, the tree replacement policy will be enforced by the city. (See tree replacementguidelines.)7. The financial security will be released upon: a) certification in writing by the forester orlandscape architect indicating the tree protection measures were installed on mass gradedlots and tree replacement is completed, if necessary; and/or b) the builders have postedsecurity for the custom graded lots.8. Removal of tree preservation measures shall require written approval from the cityengineer. Tree preservation measures shall not be removed from the site until the cityengineer has approved the grading as built plans for a mass graded site nor prior to therelease of financial securities held by the city.C. Home Builders:Lakeville Water Resources Management Plan Page 5-75

1. The city will require an individual lot tree preservation plan prepared and incorporated onthe required site survey for each custom graded lot with at least one significant tree or any lotwith trees designated as custom save. The plan shall be consistent with the original treepreservation plan for the plat. The homeowner, builder and the forester or landscapearchitect shall meet prior to the development of the individual lot tree preservation plan todetermine the placement of the home where the fewest significant trees would be destroyedor damaged. The builder will be responsible for ensuring the tree preservation plan isfollowed during building construction. On mass graded lots with at least one significant treeto be saved, builders are required to follow the tree preservation plan for the plat.2. The individual lot tree preservation plan must be certified by a forester or landscapearchitect and signed by the homeowner. The forester or landscape architect will indicate onthe plan the following:a. Size, species, and location of all significant trees.b. Identification of all significant trees proposed to be saved and significant treesproposed to be removed.c. Measures proposed to protect significant trees shall include, but are not limited to:(1) Installation of snow fencing or polyethylene laminar safety netting placed at thedrip line.(2) Placing fill against the trunk of the tree, on the root crown, and under the dripline of the tree shall be prohibited.(3) Installation of erosion control methods.(4) Prevention of change in soil chemistry due to concrete washout and leakage orspillage of toxic materials such as fuels or paints.(5) Pruning of oak trees must not take place from April 15 through July 1. Ifwounding of oak trees occurs, a nontoxic tree wound dressing must be appliedimmediately. Excavators must have a nontoxic tree wound dressing with them on thedevelopment site.3. Home builders will be required to furnish the following items for tree preservation at thetime the building permit application is submitted for all lots with at least one significant tree:a. Security of one thousand dollars ($1,000.00) per lot for tree protection requirements.b. Certified tree plan.c. Builders are liable for subcontractors that destroy or damage significant trees that wereindicated to be saved on the individual lot tree preservation plan.4. Building inspectors will monitor the tree protection measures at the time of routineinspections.5. Prior to the issuance of a certificate of occupancy and release of tree preservation security,the forester or landscape architect shall certify to the city in writing the final disposition ofsafe trees on the lot and that all the tree protection measures identified on the treepreservation plan were installed from the start of construction to the end of construction andtree replacement is completed, if necessary.D. Tree Replacement Policy: Subdividers and builders shall be required to replace the significanttrees which were indicated on the tree preservation plan to be saved but ultimately weredestroyed or damaged. The subdivider and builder shall be required to replace each of theLakeville Water Resources Management Plan Page 5-76

significant trees destroyed or damaged with two (2) replacement trees. Replacement trees mustconsist of nursery stock and be no less than the following sizes:Deciduous Trees: Maples OakLinden (Basswood)AshGreen ashBirchHoneylocustGinkgo (male only)HackberryKentucky coffee treeConiferous Trees: Common Name Scientific NameFirAbies (all varieties)/Colorado bluepseudotsugaand green sprucePicea pungensBlack Hills sprucePicea abiesAustrian pinePinus nigraWhite pinePinus strobus1.Deciduous trees: No less than two and one-half inches (2 1/2") in diameter. (Ord. 731, sec.25, 3-17-2003)2. Coniferous trees: No less than six feet (6') high.Replacement trees shall be species similar to the trees which were destroyed or damaged andcan include those species shown on the following table:Replacement trees shall not be placed on easements or street rights of way. The city shalldetermine the locations of tree replacement for subdividers' tree plans. If tree replacement isrequired on the individual lot because the builder destroyed or damaged a tree which was to besaved, the forester or landscape architect shall determine where the replacement trees shall beinstalled. (Ord. 673, sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-77

5.10 LAKEVILLE ORDINANCE 10-4-7: PROTECTED AREASWhere land proposed for subdivision is deemed environmentally sensitive by the city due to theexistence of wetlands, drainageways, watercourses, floodable areas, significant trees, steep slopesor wooded areas or its proximity to category I-a water bodies, the design of said subdivision shallclearly reflect all necessary measures of protection to ensure against adverse environmentalimpacts.Based upon the necessity to control and maintain certain sensitive areas, the city shall determinewhether said protection will be accomplished through lot enlargement and redesign ordedication of those sensitive areas in the form of outlots.In general, measures of protection shall include design solutions that allow for construction andgrading involving a minimum of alteration to sensitive areas. Such measures, when deemedappropriate by the city, may include, but shall not be limited to, the following:A. The establishment of buffers designed consistent with adopted management plans,easements and/or outlots over wetlands, drainageways and watercourses.B. The implementation of flood control measures, including ponding and infiltration designstandards as specified in adopted management plans.C. The enlargement of lots or redesign of the subdivision. (Ord. 673, sec. 1, 7-17-2000)D. The submission of a tree preservation plan subject to the review of the parks, recreation,and natural resources committee and the approval of the city council. (Ord. 698, sec. 5, 12-17-2001)E. The utilization of appropriate erosion control measures subject to approval by the cityengineer.F. Soil testing to determine the ability of the proposed subdivision to support development.G. The limitation of development on slopes steeper than three to one (3:1).H. Structure conformance to the natural limitations presented by the topography and soil soas to create the least potential of soil erosion. (Ord. 673, sec. 1, 7-17-2000)Lakeville Water Resources Management Plan Page 5-78

5.11LAKEVILLE ORDINANCE 7-13: SURFACE WATER MANAGEMENTUTILITY ESTABLISHMENTSurface water management shall be operated as a public utility pursuant to Minnesota Statutessection 444.075. (Ord. 529, sec. 1, 8-1-1994)7-13-2: DEFINITIONS:The following words, terms and phrases, when used in this Chapter, shall have the meaningsascribed to them in this Section, except where the context clearly indicates a different meaning:SURFACE WATER MANAGEMENT BUDGET: The annual budget approved by the City Councilfor surface water management including planning, monitoring, capital expenditures,maintenance, personnel and equipment.SURFACE WATER MANAGEMENT FEE: The quarterly charge for each parcel of nonexemptproperty in the City for the management of surface water.UTILITY FACTOR: The ratio of runoff volume, in inches, for a particular land use, to the runoffvolume, in inches, for a one-third-acre residential lot with thirty percent (30%) impervioussurface, assuming a 2.3-inch twenty four (24) hour rainfall event and Soil Conservation Service(SCS) "type B" soil conditions. (Ord. 529, sec. 1, 8-1-1994)7-13-3: SURFACE WATER MANAGEMENT FEES:A. The utility factors for various land uses are as follows:Classification Land UseUtility Factor1 Single-family residential 1.02 Agricultural with a homestead 1.03 Duplex 0.504 Manufactured homes 0.255 Townhomes 0.506 Apartments 0.257 Commercial/industrial 4.28 Church, school, institutions 4.29 Golf courses 4.210 Parking lots as a principal use 4.2(Ord. 666, sec. 1, 3-20-2000, eff. 1-1-2001)Lakeville Water Resources Management Plan Page 5-79

B. The surface water management fee for each tax parcel classified 1 and 2 is the single-familyresidential fee. The fee for classifications 3, 4, 5 and 6 is the single-family residential feemultiplied by the utility factor. The fee for classifications 7, 8, 9 and 10 is calculated as follows:fee for single-family residential multiplied by the utility factor multiplied by the acreage of theparcel. For tax parcels classified 7, 8, 9 and 10 with less than forty two percent (42%) impervioussurface the fee shall be adjusted by multiplying the fee by the percentage of impervious surfaceand then dividing by forty two percent (42%). (Ord. 529, sec. 1, 8-1-1994)7-13-4: CREDITS:The City Council may adopt policies for adjustment of the surface water management fees.Information to justify a fee adjustment must be supplied by the property owner. Adjustment offees shall not be retroactive. (Ord. 529, sec. 1, 8-1-1994)7-13-5: EXEMPTIONS:The following land uses are exempt from the surface water management fee: Cemeteries Gravel pits Railroads Undeveloped land Agricultural without a home Street and highway right of way (Ord. 666, sec. 2, 3-20-2000, eff. 1-1-2001)7-13-6: ACCOUNT RESPONSIBILITY OF PROPERTY OWNER:All accounts shall be the responsibility of the property owner. The owner shall be liable for thesurface water management fee for his or her property, whether or not he or she is occupying theproperty and any charges unpaid shall be a lien upon the property. (Ord. 529, sec. 1, 8-1-1994)7-13-7: PAYMENT OF FEES:The surface water management fee shall be due and payable twenty one (21) days after billing bythe City and shall be delinquent thereafter. Interest, penalties and an administrative charge ondelinquent accounts shall be established by City Council resolution. Delinquent accounts may besubmitted for collection against the respective properties. The roll shall be delivered to the CityCouncil for certification to the County Auditor for collection along with taxes. Such action isdiscretionary and may be in lieu of or in addition to any other action to collect delinquentaccounts. (Ord. 529, sec. 1, 8-1-1994)7-13-8: APPEAL OF FEE:If a property owner or person responsible for paying the surface water management fee believesthat a particular fee is incorrect, such person may file a written appeal with the City Clerk. (Ord.529, sec. 1, 8-1-1994)7-13-9: SURFACE WATER MANAGEMENT FUND:A separate fund shall be maintained for surface water management fees and expenditures. (Ord.529, sec. 1, 8-1-1994)Lakeville Water Resources Management Plan Page 5-80

5.12 SPILL CONTAINMENT PROCEDUREThe Lakeville Fire Department is trained in operational procedures needed when a contaminantspill is reported. The spill is immediately reported to State Duty Officer of the MinnesotaPollution Control Agency, and the Dakota County Special Operations Team. The FireDepartment responds in cooperation with and as per the direction of these agencies.As part of the development of the South Creek Management Plan, the South Creek ManagementPlan Subcommittee examined the City’s emergency response procedures for accidentalhazardous chemical discharge. At that point in time, it did not appear that accidental dischargeshave had an impact on South Creek despite some incidents. This is probably due in large part tothe excellent state of awareness and response procedures in place for the Lakeville FireDepartment and links established with the Minnesota Pollution Control Agency to address spills.In consultation with the Lakeville Fire Department the Subcommittee recommended thatadditional spill containment equipment be stored in the Airlake Industrial Park, preferably atthe City Maintenance Facility located there. This would provide ready access to spillcontainment equipment in Airlake beyond that carried by Fire Department vehicles on all callsin Lakeville. This recommendation acknowledged the higher potential for substancesdetrimental to the sensitive resource in the area.The Subcommittee also recommended periodic updates for businesses in the Airlake IndustrialPark and firefighters regarding water quality issues and concerns about trout streamvulnerabilities to chemical and temperature contamination. This should take the form ofperiodic informational mailings and could include a hotline for businesses to call with concernsor questions.The above recommended tasks are ongoing.Lakeville Water Resources Management Plan Page 5-81

5.13 WATERSHEDSThe city of Lakeville is split between two watersheds: the Vermillion River watershed, and theBlack Dog watershed (see Figure 5.13). The Vermillion River watershed flows ultimately to theMississippi River and the Black Dog watershed flows to the Minnesota River. The watersheddivide places about 6 square miles in the northwest part of the city within the within Black Dogand the greater Minnesota River watershed. This area includes the Orchard Lake and CrystalLake Stormwater Districts. These watersheds generally drain north and west to the Credit River.The remaining areas of the city belong to the Vermillion and ultimately the Mississippi Riverwatershed. These watersheds generally drain to the southeast. About 16% of the city lies withinthe Black Dog watershed while the remaining 84% of the City area drains east to the VermillionRiver.5.13.1 Vermillion River Watershed Joint Powers Organization5.13.1.1 Watershed SummaryThe Vermillion River watershed is the largest in the Twin Cities (Minneapolis/Saint Paul)metropolitan area. Beginning in southeastern Scott County, the River flows acrosscentral Dakota County to the city of Hastings where it drops 90 feet. Below the falls theriver meanders a short way downstream and then splits: one branch flows north to theMississippi River; the other flows south paralleling the Mississippi River 20 miles beforejoining the Mississippi River near the City of Red Wing in Goodhue County.The Vermillion River has 45.5 miles of designated trout stream. According to TroutUnlimited, it is the only world class trout stream within a major metropolitan Area in theUnited States. The Minnesota Department of Natural Resources and the Twin Citieschapter of Trout Unlimited recently completed a survey of the trout population in theVermillion River. The survey found the number of trout hatched in the spring of 2006was higher than in previous years. Preserving the Rivers water quality and temperatureare essential for trout reproduction.The Vermillion River Watershed Joint Powers Organization (VRWJPO) is a WatershedManagement Organization as defined in the Metropolitan Surface Water Management Act(Minn. Statutes Chapter 103B). This Act provides the VRWJPO with power to accomplishits statutory purpose: to protect, preserve and manage surface and groundwater systemswithin the VRWJPO.A number of sensitive habitats and communities exist in the watershed including thedesignated trout stream areas, other natural communities, rare species, and wetlands. Thetrout stream designated areas were recently expanded and trout populations are sustainable.Trout and their habitats may be threatened by anticipated urban development ifLakeville Water Resources Management Plan Page 5-82

development is completed without appropriate stormwater management. Other sensitiveresources, such as natural communities, rare species, and wetlands have been largelydepleted or have been substantially altered throughout the watershed. This has increased thevalue of remaining natural communities and resources.The VRWJPO has adopted a Watershed Plan pursuant to the Acts and Minn. Rules Chapter8410 in November 2005. This plan identified the following issues facing the VermillionRiver Watershed:River flows have increasedSurface water quality is threatened or impairedVermillion River channel/corridor is impacted and sensitive to changeSensitive resources are present and/or threatened or impairedGroundwater quality is threatened or impairedAdditional development is expectedData for making informed decisions is limitedPublic awareness about water resources in the Watershed and appropriate stewardship islimitedThe Watershed Plan provides the management goals, policies and objectives that theVRWJPO will use to protect, improve, preserve, and manage water resources in theVRWJPO, and the need and reasonableness for standards, rules, and ordinances to enforcethe objectives of the plan. The VRWJPO Standards implement the plan’s policies, objectives,and actions.5.13.1.2 Watershed Goals and PoliciesThe VRWJPO adopted its current Watershed Plan on November 3, 2005. This Planidentified the goals and policies of the VRWJPO. Subsequently, the VRWJPO adoptedStandards (October 26, 2006) and Rules (March 22, 2007) based on those policies.Floodplain Alteration PoliciesIt is the policy, objective, or action of the VRWJPO to:1. Protect the natural function of the floodplain storage areas from encroachment.2. Work to maintain no net loss of floodplain storage.3. Manage floodplains to maintain critical 100-year storage volumes.4. Require Local Plans to include a provision that restricts construction of newstructures in flood prone areas.5. Require Local Governments to adopt floodplain ordinances that are consistent withDakota and Scott County water resources plans and ordinances.6. Limit floodplain alterations in order to obtain “no net loss” of floodplain storage, andincluding the preservation, restoration, and management of floodplain wetlands.Lakeville Water Resources Management Plan Page 5-83

7. Ensure that local governments require compensatory storage for new developmentswithin the floodplain.Wetland Alteration PoliciesIt is the policy, objective, or action of the VRWJPO to:1. Work to achieve no net loss of wetlands in the Vermillion River Watershed.2. Replace lost wetlands in the same subwatershed whenever possible.3. Provide equal or greater functions and values for lost wetlands at the replacementratios dictated by the Wetland Conservation Act.4. Avoid direct or indirect wetland disturbance in accordance with State and Federalrequirements and approved local wetland management plans.5. Limit the use of high quality wetlands for stormwater management where otheralternatives exist.6. Avoid fragmentation of natural areas and corridors when feasible and mitigate whenunavoidable.Buffer PoliciesIt is the policy, objective, or action of the VRWJPO to:1. Require buffers, acting as filter strips around every wetland based on its managementclassification.2. Avoid fragmentation of natural areas and corridors when feasible and mitigate whenunavoidable.3. To protect wetlands from chemical, physical, biological, or hydrological changes so asto prevent significant adverse impacts.Stormwater Management PoliciesIt is the policy, objective, or action of the VRWJPO to:1. Manage stormwater to minimize erosion.2. Require land disturbing activities including new development and redevelopment(urban/rural), road construction, agricultural protections and other rural uses withinthe watershed to address impacts on water resources, including cumulative impacts.3. Require development plans to consider impacts on local natural resources andcorresponding receiving waters.4. Minimize impacts of runoff from land disturbing activities including newdevelopment and redevelopment (urban/rural), road construction, agriculturalproduction, and other rural land uses, and preserve a viable cold-water fishery bydeveloping stormwater rate and volume control techniques.5. Develop standards that include requirements for controlling stormwater runoff byminimizing impervious surfaces, maximizing infiltration, requirements for cities andLakeville Water Resources Management Plan Page 5-84

townships to control stormwater rates crossing municipal boundaries, and creatingstormwater storage that addresses not only peak flows for extreme events, but takesinto account the cumulative effects of runoff volume, and will include stormwaterrate control requirements.6. Mitigate and reduce impacts of past increases in stormwater discharge ondownstream conveyance systems.7. Improve the condition of waterbodies in the watershed included on the MPCAimpaired waters [303(d)] list so that these waterbodies can be removed from the list.8. Encourage the use of existing natural retention and detention areas for stormwatermanagement to maintain or improve existing water quality.9. Minimize water quality impacts (including thermal impacts) from land disturbingactivities, new development and redevelopment, (urban/rural), road construction,agricultural production, and other rural uses.10. Develop standards that include requirements for water quality treatment,requirements for addressing thermal impacts, address preservation of riparianbuffers, potentially include measures for minimizing nitrate contamination in surfacewaters, and require erosion/sedimentation control practices consistent with theNPDES Phase II Rule.11. Ensure stormwater management systems are maintained by establishing StormwaterManagement System Maintenance Standards for cities and townships within thewatershed.Drainage Alteration PoliciesIt is the policy, objective, or action of the VRWJPO to:1. Use existing natural retention and detention areas for stormwater management tomaintain or improve existing water quality.2. Manage stormwater to minimize erosion.3. Allow outlets from landlocked basins, provided such outlets are consistent with Stateand Federal regulations, and the downstream impacts, riparian impacts, and habitatimpacts of such outlets have been analyzed and no detrimental impacts result.4. Mitigate and reduce the impact of past increase in stormwater discharge ondownstream conveyance systems.5. Address known flooding/erosion problems that cross jurisdictional boundaries andaddress other boundary issues and the diversion/alteration of watershed flows inlocal water plans.6. Address gully erosion problems in the watershed.7. Maximize upstream floodwater storage.Agricultural PoliciesThe VRWJPO approach to Agricultural Standards is voluntary at this time and is based on:Lakeville Water Resources Management Plan Page 5-85

1. Requiring a Stewardship Management Plan as part of being eligible to receive costshare for incentive practices sponsored by the VRWJPO; and2. Implementation of the State of Minnesota Nutrient Management Plan of 1990 andthe Pesticide Management Plan of 2005.VRWJPO Standards address the policies and issues identified above and in the VRWJPOWatershed Plan. In addition to protecting natural resources, the VRWJPO Standards areintended to minimize future public expenditures and liability on issues caused by theimprovement or alteration of land and waters. The Standards in this case serve asintermediate between the Plan Policies and the Watershed Rules. The adopted VRWJPOStandards (2008 amended) are included in Appendix F of this Plan.The VRWJPO Rules, adopted March 22, 2007, implement the Watershed Plan’s policies,objectives, and actions. The rules include regulations for development and other grounddisturbing activities as well as stormwater and natural resource management. The Rules areincluded in this Plan as Appendix F.The VRWJPO recognizes that the control and determination of appropriate land use is theresponsibility of the Local Units of Government (LGUs; i.e., municipalities and counties). InMarch 2007, the VRWJPO adopted Rules consistent with these Standards in the event itacquires the authority of a watershed district under Minn. Stat. 103B.211, Subd. 1(a)(3).LGUs are responsible for adopting Local Water Plans that implement the VRWJPOWatershed Plan. These Standards were incorporated into the VRWJPO Watershed Planthrough a plan amendment enacted in November 2006. Pursuant to Minn. Stat. §103B.235,the LGUs must complete Local Plans within a time period specified in the Watershed Plan,which is two years from the original Watershed Plan approval. After approval of the LocalPlans the LGUs have 120 days to begin implementing the plans and 180 days to amend theirofficial controls. During the interim period between VRWJPO rule adoption and localgovernment adoption of ordinances and controls, the VRWJPO will, in LGUs without LocalWater Plans approved by the VRWJPO:1. Work with local governments to revise/adopt their ordinances and other controls forconformance with the VRWJPO Plan.2. Assist the townships in developing a model ordinance that incorporates the VRWJPOStandards.3. Prior to local government issuing a permit, require that local governments submitproposed land alteration plans to the VRWJPO for review and comment, if the plansinclude any of the following conditions:Variances from the local government’s ordinance that affect surface water orimpact surface water/groundwater interactionsDiversionsIntercommunity flows (upon request of adjoining communities)Project site size of 40 acres or moreOther proposed activities, as identified in the VRWJPO Plan.Lakeville Water Resources Management Plan Page 5-86

The VRWJPO may also conduct other selected project reviews in order to evaluate theimplementation of LGU ordinances and permitting programs.The VRWJPO envisions three categories of permitting responsibility following adoption ofthe VRWJPO rules:Category 1 VRWJPO assumes responsibility for all permitting.Category 2 LGUs assume responsibility for all permitting.Category 3 LGUs assume responsibility for all permitting, with VRWJPO permittingrequired under certain circumstances.Following VRWJPO rule adoption, the VRWJPO will evaluate local government ordinancesto determine if they match the VRWJPO Standards. If a local government’s ordinances arefound to be insufficient (i.e., do not meet the VRWJPO Standards), the VRWJPO willimplement a permitting program in that community (Category 1).If an LGU incorporates the VRWJPO Standards into its ordinances and controls, anddemonstrates compliance with the VRWJPO Standards, that LGU will be responsible forpermitting (Category 2). The VRWJPO will require LGUs responsible for permitting tosubmit some proposed land alteration plans to the VRWJPO for review and comment eachyear through a VRWJPO evaluation program. Land alteration plans with the followingconditions are particularly important to the VRWJPO for review:DiversionsIntercommunity flows (upon request from adjoining communities)Project site size of 40 acres or moreProjects that are adjacent to or appear to impact major waterways or uniquenatural resourcesAll land alteration plans that require an amendment to or a variance from the adopted localwater plan must be submitted to the VRWJPO for review and approval or denial asprescribed by Minn. Stat. 103B.211. The VRWJPO will enforce its permits and Rules asallowed by Minn. Stat. Chs. 103B and 103D. The VRWJPO may also evaluate localgovernment permitting programs. If these evaluations show noncompliance with theVRWJPO’s Standards and/or the local government’s ordinances, the VRWJPO willimplement a permitting program in that local government.The City of Lakeville, through this Plan and update of its ordinances intends to beresponsible for permitting within the City (Category 2).5.13.1.3 Capital Improvement ProgramThe VRWJPO Budget with Capital projects information is available at:http://www.co.dakota.mn.us/CountyGovernment/PublicEntities/VermillionJPO/Commission.htmLakeville Water Resources Management Plan Page 5-87

5.13.2 Black Dog Watershed Management Organization5.13.2.1 Watershed SummaryThe Black Dog Watershed Management Organization (BDWMO) is located innorthwestern Dakota County and a portion of northeastern Scott County, Minnesota.The BDWMO contains portions of the cities of Apple Valley, Burnsville, Eagan, Lakeville,and Savage. Surface water in the BDWMO ultimately discharges to the Minnesota River.The BDWMO covers 17,730 acres or 27.7 sq. mi 2 ; 72% of the watershed lies within theCity of Burnsville, 19% (5.25 sq. mi.) within the City of Lakeville, and 8% within the Cityof Apple Valley. The cities of Eagan and Savage each constitute less than 1% of theBDWMO.The Murphy Hanrehan, Kingsley Lake and Orchard Lake subwatersheds are tributary to theCredit River. Water management activities in these subwatersheds are of particular interestto Scott County and the city of Savage. The other subwatersheds in the BDWMO dischargethrough the Lower Minnesota River Watershed District before reaching the Minnesota River.The cities of Apple Valley, Burnsville, Eagan, Lakeville and Savage executed a joint powersagreement in June 1985, establishing and empowering the Black Dog WatershedManagement Organization (BDWMO). The BDWMO was formed in response to therequirements of the Metropolitan Surface Water Management Act (“Chapter 509,” nowrecodified to Minnesota Statutes 103B). The Act required, among other things, thepreparation of watershed management plans in the Minneapolis-St. Paul metropolitan area.The Water Resources Board (now the Board of Water and Soil Resources), formally approvedthe Black Dog Watershed Management Plan on November 22, 1989. In 1999, the DakotaCounty portion of the Credit River WMO was added to the BDWMO. As a result, the membercities executed a revised and restated joint powers agreement, and the BDWMO and ScottCounty signed a memorandum of understanding regarding the management of the CreditRiver portion of the BDWMO.5.13.2.2 BDWMO Goals and PoliciesWith its 2002 Water Management Plan the BDWMO general purposes changed with somesimilar to those stated in the older 1989 Plan. The BDWMO’s general goals are to:Keep regulation at the local level—the BDWMO will not administer a permit program.Assist member communities with intercommunity floodplain and runoff planning andwith mediation of water management disputes between communities.Monitor, classify and manage strategic water resources to meet their intended use.Monitor, evaluate, and/or model stormwater runoff quality.Improve the quality of stormwater runoff reaching the Minnesota River.Lakeville Water Resources Management Plan Page 5-88

Manage intercommunity stormwater runoff, flooding and other water quantity issues.Develop policies to be implemented by the cities to protect the BDWMO’s waterresources.Assess performance of the BDWMO and the member cities toward achieving the goalsstated in the Watershed Plan.Provide member cities with useful information about the BDWMO, its activities, andwater resource management.Educate all watershed citizens and member cities in water resource issues and BDWMOactivities.Water Quality Goals and PoliciesThe water quality goals of the BDWMO are to:Manage the BDWMO water resources on a regional basis to meet their established goals.Maintain or restore the water quality of the BDWMO water resources to allow for thecontinuation or enhancement of existing recreation activities and habitat.To accomplish its goals, the BDWMO established a water body classification system anddetermined the respective roles of the BDWMO and the cities in water quality management.Policy 1. All water bodies in the BDWMO will be classified according to either the BDWMOlake and pond classification system or the city’s wetland classification system. TheBDWMO lake and pond classification system contains five categories that will be used bythe BDWMO and member cities to classify lakes and ponds, defined as follows:Category I. Water bodies in this category are typically used for swimming and otherdirect contact recreational activities. These water bodies have the highest/best waterquality and are usually the most popular water bodies with the public.Category II. Water bodies in this category are typically used for indirect contactrecreational activities such as boating and fishing, that involve incidental contact withlake water. These water bodies have poorer water quality than Category I water bodies,but are still popular with the public.Category III. Water bodies in this category serve important functions for wildlifehabitat and aesthetic enjoyment, and may also provide opportunities for warm-waterfishing, provided winter kill does not occur. These water bodies may have poorer waterquality than Category I and II water bodies and typically are not viewed as swimmablebecause of lower water quality or the nature of their shorelines.Category IV—Nutrient Traps. Water bodies in this category are intended to reducedownstream loading of phosphorus and other nutrients that contribute to waterpollution. These ponds are designed to have phosphorus removal efficiencies of at least50 percent.Lakeville Water Resources Management Plan Page 5-89

Category V—Sediment Traps. These water bodies are similar to Category IV waterbodies, but are too small to effectively remove a significant fraction of nutrients. Thesebasins will generally have phosphorus removal efficiencies of less than 50 percent.Policy 2. Category I-III water bodies will be managed for non-degradation of water quality, withallowance for natural variability. This means that developments and city projects should bedesigned to preserve existing water quality so far as reasonably possible, even when existingwater quality is better than the water body classification might otherwise infer. To conformto this policy, implementation of best management practices will be required duringdevelopment and other types of construction.Policy 3. Category I-III water bodies will also be managed to preserve and promote bio-diversityand improve aesthetics.Policy 4. The BDWMO set criteria for determining which water bodies should be managed by theBDWMO (“strategic” water resources). Strategic water resources are water resources ofbroad watershed significance that are important to a larger population than just themunicipalities in which they are located. Water bodies need to meet four of the following fivecriteria to be considered strategic water resources:Water bodies or streams that receive drainage from more than one community ormunicipality.Water bodies that are an important regional resource for either 1) recreational (e.g.,swimming, boating, adjacent regional park, etc.) or 2) wildlife/natural resource reasons.Water bodies that directly discharge into a significant downstream resource such as theMinnesota River, a trout stream, or another significant resource as determined by theBDWMO.Water bodies that have higher water quality than typically found in similar lakes, ponds,or streams.Water surface area 50 acres or more.The BDWMO considers Crystal Lake, Orchard Lake, Keller Lake, Kingsley Lake, Lac Lavonand Sunset Pond to be strategic water resources. Other water bodies could be consideredstrategic, if agreed to by the cities and the BDWMO.Policy 5. Responsibilities for managing lake and pond water quality within the BDWMO aredescribed in the paragraphs below. The projects and studies identified as the BDWMO’sresponsibility may be completed by one of the member cities, but will be funded throughBDWMO cost sharing.Policy 6. In lakes where evidence suggests aquatic plants act to improve water quality andhabitat, the BDWMO discourages harvesting of native (i.e. non-invasive) aquatic plants.Lakeville Water Resources Management Plan Page 5-90

Policy 7. The BDWMO will limit its other water body management roles to those involvingintercommunity watersheds, at the request of the involved cities.The BDWMO will classify, set action levels, monitor water quality, and track water qualitytrends for all strategic water resources, and will implement lake management actions (asneeded) for those strategic water resources with intercommunity tributary watersheds. TheBDWMO classified the strategic resources based on their existing and projected future use,taking into account their existing and projected water quality, and/or the presence ofecologically or biologically unique resources. These classifications may be revised, based onexisting and desired uses of the water bodies and the results of future water quality andaesthetic/habitat monitoring. The BDWMO will follow a plan amendment process if there isa need to change the classification of a water body. The classification and numeric goals forthe strategic water bodies are as follows:Crystal Lake —Based on its existing and desired use, the BDWMO classified Crystal Lakeas a Category I water body. The current (1997 to 1999) water quality of Crystal Lake (totalphosphorus concentration, chlorophyll-a concentration and Secchi disc transparency) placesthe lake within Category I, but the water quality varies greatly over the summer.In 2003 the BDWMO completed the Crystal and Keller Lake Use Attainability AnalysisDiagnostic Feasibility Study: Water Quality Issues and Potential Restorative Measures.Based on the study the City of Burnville and the BDWMO set a Secchi disc transparency goalof 2.1 meters for Crystal Lake. The “action” level for the Lake has been set as 1.6 meters. TheCity of Lakeville has adopted the same goal and action level for Crystal Lake.Orchard Lake—Based on its existing and desired use, the BDWMO classified Orchard Lakeas a Category I water body. The current water quality of Orchard Lake puts the lake on theborder between a Category I and Category II classification. With the upcoming land usechanges in the watershed, the future water quality of Orchard Lake is predicted to declinesomewhat, if water quality best management practices are not undertaken in the watershed.As noted in Section 4.1.3, the City of Lakeville is working toward implementation of all thebest management practices in the Orchard Lake Management Plan (2000) to maintain thewater quality of Orchard Lake. The BDWMO set the action level for Orchard Lake at 1.6meters, based on its classification and use as a Category I lake. The statistical analysis of theOrchard Lake data would have resulted in an action level of about 0.9 meter, which is in theCategory III range. As a result, the action level was set using the levels given in policy 5(d)for lakes with insufficient water quality data. Lake management actions have already beentaken, including completion of a diagnostic feasibility study, completion of a lakemanagement plan and implementation of best management practices. The city of Lakeville isthe only BDWMO member that contributes water to Orchard Lake. Since the tributarywatershed does not span more than one city, it is the city of Lakeville’s (not the BDWMO’s)responsibility to identify and implement feasible water quality improvement initiatives toachieve the Orchard Lake water quality goals set in this plan.Lakeville Water Resources Management Plan Page 5-91

Kingsley Lake—The current water quality of Kingsley Lake places the lake within theCategory I classification and, even with land use changes in the watershed, the future waterquality is predicted to remain within Category I. However, there is not a public park, a publicboat access nor a swimming beach on the lake. Based on its existing and projected futureuse, the BDWMO classified Kingsley Lake as a Category II water body. Although the goal forKingsley Lake is non-degradation of its water quality, the city of Lakeville would like to directits water quality improvement efforts at lakes that provide more public use, such as OrchardLake. The action level for Kingsley Lake, based on a Category II classification, is a Secchi discreading of 1.0 meters. The city of Lakeville is the only BDWMO member that contributeswater to Kingsley Lake. Since the tributary watershed does not span more than one city, it isthe city of Lakeville’s (not the BDWMO’s) responsibility to identify and implement feasiblewater quality improvement initiatives, if needed, to achieve the water quality goals set in thisWRMP.The cities and the BDWMO share water quality data. Certain water quality managementactions will need to be taken, depending on whether the most recent water quality data(summer average) is “better than” or “worse than” the action level and whether the long-termwater quality trend is improving, steady, or degrading. For strategic resources, therecommended action will be undertaken by the cities, at the direction of the BDWMO. If acity does not undertake a needed project for a strategic resource, then the BDWMO willconsider undertaking the project. In this situation, the BDWMO would assess the projectcosts back to the cities, in accordance with the joint powers agreement. For non-strategicresources, the cities are to take the recommended action.It is the intent of the BDWMO to continue to cooperate with the member cities in resolvingwater quality improvement project issues. Diagnostic -feasibility studies will be used todetermine the needed water quality improvement projects and the estimated costs of theprojects. The BDWMO will undertake a water quality improvement project only as a lastresort. The BDWMO will rely on a continued collaborative/cooperative approach and a spiritof partnership with its member cities to resolve issues regarding implementation of waterquality improvement projects. The BDWMO will involve the cities in the decision-makingprocess, taking into account cost effectiveness and the cities’ financial capability to fundwater quality improvement projects. In accordance with the joint powers agreement, anymember city may appeal cost allocation decisions made by the BDWMO.The member cities may enter into individual joint powers agreements with one anotherregarding cost splits for lake water quality and aesthetic/habitat management projects, as analternative to using the methods set forth in the BDWMO joint powers agreement.Stormwater Management PoliciesThe BDWMO stormwater management goals are to:Improve the quality of stormwater runoff reaching the Minnesota River by reducingnonpoint source pollution (including sediment) carried as stormwater runoff.Lakeville Water Resources Management Plan Page 5-92

Maintain or improve the quality of stormwater runoff reaching the calcareous fen (Black Dogfen) and the nearby trout streams.Manage intercommunity stormwater flows.Minimize flood damage to residential, business, commercial and public structures andproperty, and protect against increased flooding caused by land disturbing activities andother projects.Policy 1. Although the BDWMO will not be administering a permit program, the BDWMOwill: Review projects for consistency with the BDWMO plan, as requested by membercities or other governmental agencies. Review and approve any proposed changes to the intercommunity stormwatersystem that are inconsistent with an approved local watershed management plan. Review and approve any changes to the approved local plan that would cause thelocal plan to be inconsistent with the BDWMO plan. Review member city comprehensive plan changes that require review by theMetropolitan Council. Be informed by the member cities regarding other revisions totheir comprehensive plans that affect water management.Policy 2. Through their local watershed management plans, the cities are to identify feasibleand effective locations for implementing water quality best management practices thatwill improve the quality of stormwater runoff. This is in addition to the citiesimplementing (or requiring the implementation of) best management practices as part ofdevelopment.Policy 3. When areas redevelop, the BDWMO encourages the member cities to take fulladvantage of the opportunity to improve stormwater runoff management and waterquality. The cities are to require that all stormwater management upgrades conform tothe policies in the BDWMO Watershed Plan.Policy 4. The BDWMO will develop water quality models for the unmonitored BDWMOsubwatersheds that discharge into the Minnesota River. The water quality models willestimate phosphorus loading from the subwatersheds and identify “hot spots.” Themodel results could then be used to plan runoff water quality improvements and assessthe success of the member cities’ water quality initiatives and best managementpractices.Policy 5. BDWMO involvement in intercommunity flood control issues (issues where thetributary watershed spans more than one city or outflows cross city/county/WMOboundaries) is as a facilitator. As facilitator, the BDWMO will assist in fairly allocatingcosts among the member cities for intercommunity flood control projects.Policy 6. The BDWMO will coordinate intercommunity stormwater runoff design andplanning with the member communities by:Lakeville Water Resources Management Plan Page 5-93

Reviewing each member city’s local watershed management plan for consistency withthe BDWMO goals and intercommunity planning.Calculating the cost apportionment between cities for water resources projects withintercommunity participation.Policy 7. The BDWMO promotes stormwater retention through infiltration practices wherepractical, taking into account soil conditions, groundwater supply issues, safety issues,snow removal, and other concerns. The cities are to request that project proposersconsider methods for reducing the amount of impervious surface on their sites. Methodsto consider include: Reducing road widths, such as allowing parking on only one side of a residentialstreet. Eliminating pavement in the center of cul-de-sacs. Reducing sidewalk widths. Allowing and providing for shared parking. Creating a smaller building footprint (e.g. building two story houses instead ofone story houses). Installing semipermeable/permeable paving, where feasible (e.g. overflowparking lots).Policy 8. The BDWMO encourages the member cities to promote and incorporate LowImpact Development design concepts into development and redevelopment projects.The primary goal of Low Impact Development is to mimic pre-development sitehydrology through storage, infiltration, evaporation, maintenance of natural drainagecourses, and other methods.Policy 9. For the BDWMO subwatersheds tributary to the Credit River, the following policiesapply: For undeveloped subwatersheds, post-development discharge rates leaving theBDWMO will be maintained at or below predevelopment rates for all flood eventsup to and including the critical 100-year event. For fully developed subwatersheds, discharge rates leaving the BDWMO will bemaintained at existing rates for all flood events up to and including the critical100-year event.This policy applies to increased watershed areas that may result from future drainage ofpresently landlocked watersheds. To conform to the requirements of this policy, the cityof Lakeville will restrict the Orchard Lake outlet to maintain its peak outflow at 65 cfs.This policy will help prevent capacity and erosion problems downstream, in Credit RiverTownship and the city of Savage.Policy 10. If water quality issues arise in the Credit River watershed downstream of theBDWMO, the BDWMO will cooperate with Scott County in analyzing and addressingthese issues.Lakeville Water Resources Management Plan Page 5-94

Policy 11. For the subwatersheds that discharge from the BDWMO to the Lower MinnesotaRiver Watershed District, the following policies apply: For undeveloped subwatersheds, post-development discharge rates leaving theBDWMO will be maintained at or below predevelopment rates for all flood eventsup to and including the critical 100-year event. For fully developed subwatersheds, discharge rates leaving the BDWMO will bemaintained at existing rates for all flood events up to and including the critical100-year event.The BDWMO encourages the member cities to reduce discharge rates wherever possible,with the goal of reducing discharge rates to pre-development levels (or lower).Policy 12 The BDWMO supports the use of regional detention and treatment facilities forwater quality improvement and water quantity control. Where regional detention andtreatment facilities that meet the BDWMO standards are already in-place or plannedwithin the city’s current capital improvements plan, on-site detention and treatmentfacilities are not required at development sites. To meet the BDWMO standards in othersituations, the city’s local watershed management plan will specify the manner by whichthe city will ensure future compliance with the BDWMO standards. Suggested methodsinclude, but are not limited to: Requiring construction of permanent or temporary on-site detention/treatmentbasins meeting the BDWMO standards; or Requiring use of other water quality treatment measures, such as treatmentdevices/structures connected to the storm sewer system and/or infiltrationpractices; or Collecting an appropriate fee from the project proposer as a contribution towardconstruction of a future regional detention/treatment facility within the samesubwatershed.Policy 13. The member cities are to require runoff control plans for land development andconstruction work that will disturb one or more acres of land. Local watershedmanagement plans and city ordinances are to include the requirements and proceduresfor reviewing, approving and enforcing the runoff control plans.Policy 14. The BDWMO encourages its member cities to adopt ordinancescontrolling/regulating the use of phosphorus in fertilizer.Stormwater System Design Requirement PoliciesPolicy 1. The level of protection along all trunk conveyors, streams, and channels and aroundall wetlands, ponds, detention basins, and lakes shall be based on the critical-duration100-year flood.Policy 2. Non-trunk stormwater systems should be planned to provide discharge capacity forthe critical-duration runoff event that is not less than a 5-year frequency event,preferably a 10-year frequency event (level of service). Where the planned level of serviceLakeville Water Resources Management Plan Page 5-95

would cause hardship in operation of a downstream system, the owner may design for alesser level of service if the following circumstances are present: The proposed new or replacement system will not have a longer life than that ofthe existing downstream system. It is not practical to incorporate temporary measures into the new system tomitigate the effects of the new system on the downstream system.Policy 3. The cities are to ensure that proposed development, redevelopment, and/orinfrastructure projects will not overtax the existing downstream stormwater drainagesystem.Policy 4. The member cities are to incorporate emergency overflow structures (i.e. swales,spillways), where feasible, into pond outlet structure designs to prevent undesiredflooding resulting from storms larger than the 100-year (1 percent) event or pluggedoutlet conditions.Policy 5. As areas develop or redevelop, the cities are to secure easements or fee title to thestormwater system.Policy 6. The BDWMO encourages cities to incorporate multi-stage outlets into their ponddesigns to control flows from smaller, less frequent storms and help maintain base flowsin downstream open channels.Policy 7. The cities are to set minimum building elevations at least 1-foot above the critical100-year flood elevation for structures adjacent to inundation areas. Cities shouldconsider the effects of events larger than the 100-year flood when setting minimumbuilding elevations. Higher minimum building elevations should be considered forstructures adjacent to ponding areas with large tributary watersheds and for structuresadjacent to landlocked basins.Policy 8. The BDWMO establishes the following policies regarding landlocked basins:1. The flood levels established in local watershed management plans shall take intoconsideration the effects of water level fluctuations on trees, vegetation, erosionand property values. Steeply sloped shorelines that are subject to slope failureand shoreline damage should not be in contact with flood water for extendedperiods of time.2. Only the existing tributary area may discharge to a landlocked basin, unlessprovision has been made for an outlet from the basin. The form of outlet mayrange from temporary pumps to gravity storm sewers. The outlet shall be inplace before increased water levels are likely to affect vegetation, slope stabilityand property values.3. The BDWMO encourages cities to reduce impervious area coverage and increaseinfiltration opportunities in watersheds tributary to landlocked basins.4. If outlets from landlocked basins are needed, the BDWMO encourages cities tokeep outflow rates low enough to allow for as much infiltration as possible,Lakeville Water Resources Management Plan Page 5-96

however rates should not be so small as to cause extended durations of highwater levels that would result in damage to upland vegetation.5. When the cities establish high water elevations and whether outlets are neededfor landlocked basins, the BDWMO encourages the cities to account for longduration events, such as multiple -year wet cycles and high runoff volume events(i.e. snowmelt events that last for many weeks).6. The member cities need to consider both the water quality and flooding impactsof proposed outlets from landlocked basins on downstream water resources.Policy 9. For new stormwater discharge points/outfalls: the cities are to providepretreatment (at least grit removal) of stormwater prior to its discharge to wetlands andother water resources.Policy 10. For existing stormwater discharge points/outfalls: the BDWMO encourages thecities to provide pretreatment of stormwater prior to its discharge to wetlands and waterresources.Policy 11. For existing inlets to the stormwater system that receive direct stormwater runoff(i.e. no pretreatment) from highly impervious land uses, the BDWMO also encouragesthe cities to provide pretreatment of stormwater runoff.Policy 12. The BDWMO will monitor the water quality of the stormwater runoff thatdischarges into the Minnesota River from the BDWMO.Policy 13. The BDWMO will work the Metropolitan Council to set target pollutant loads forthe BDWMO, which will likely be based on the WOMP station monitoring results. Afterthe target pollutant loads have been set, the BDWMO will investigate additional pollutionreduction needs in the watershed.Policy 14. The BDWMO encourages the cities to recruit volunteers to participate in theDNR’s lake level monitoring program for DNR protected water bodies. The DNR setsand maintains the lake level indicator (staff gage) and the volunteer reads and recordsthe level.Requirements for Local Watershed Management PlansThe BDWMO has deferred to the member cities many of the surface water resource datarequirements required in MN Rules 8410. The following policies incorporate some of therule’s requirements.Policy 1. Local watershed management plans are to include maps of the existing stormwatersystem, including ponds, trunk pipes, drainageways and stormwater outfalls. The citiesare encouraged to also show the location of stormwater treatment facilities (i.e. sumpmanholes, prefabricated stormwater treatment systems).Lakeville Water Resources Management Plan Page 5-97

Policy 2. The local plans are to identify the highly impervious areas with significant potentialfor water quality improvement. The cities are encouraged to develop (in the local plan orin the future) a water quality improvement program for these areas. The components ofsuch a program could include the following: Retrofit opportunities Redevelopment opportunities Site-specific BMPs, such as sump manholes or prefabricated structures Special/targeted street sweeping program.Policy 3. The cities are responsible for operating and maintaining channels, drainageways,pond/lake outlets, watercourses, etc. in the BDWMO. These operation and maintenanceissues are to be addressed in the local watershed management plans.Policy 4. The cities must prepare and adopt (local) watershed management plans thatconform to the goals, policies, standards and criteria presented in the BDWMO plan,including the erosion control and runoff control plan requirements. Existing and/orproposed permit programs will need to be described in the local watershed managementplan.Policy 5. In their local watershed management plans, each member city shall identify the100-year flood peak flow rates at each intercommunity conveyor and overflow point.Hydrographs should be provided, if available.Policy 6. Local watershed management plans must show subwatersheds and drainagepatterns, and present detailed hydrologic information, including outlet elevations, 5-year(or 10-year), and 100-year existing/proposed water levels, 5-year (or 10-year) and 100-year existing/proposed flow rates, runoff volumes and storage volumes, andexisting/proposed outlet information. A hydrograph method based on sound hydrologictheory shall be used to analyze stormwater runoff for the design or analysis of flows inconveyors, streams, and channels and flows to ponds and wetlands. Reservoir routingprocedures and critical-duration 100-year runoff events shall be used for design ofdetention basins and outlets.Policy 7. Local watershed management plans are to identify subwatersheds tributary toeither the Black Dog fen wetland complex or the nearby trout streams. The cities are tomaintain or reduce the size of these tributary watersheds. The BDWMO encourages themember cities to reduce stormwater discharge rates and volumes within trout stream andfen watersheds whenever possible, with the goal of reducing discharge rates to predevelopmentlevels (or lower).Erosion and Sediment Control PoliciesThe goals of the BDWMO are to:Prevent erosion and sedimentation to the greatest extent possible.Lakeville Water Resources Management Plan Page 5-98

Implement soil protection and sedimentation controls whenever necessary to maintainhealth, safety, and welfare.Policy 1. The BDWMO will facilitate intercommunity erosion and sediment control projectsby performing studies, preliminary designs, feasibility reports and calculating the costapportionment between cities, as requested by the cities.Policy 2. Local watershed management plans and city ordinances are to includerequirements for the preparation of erosion control plans, in addition to runoff watermanagement plans, which require the use of best management practices on constructionproject sites.Policy 3. Local watershed management plans are to address erosion and sediment controlproblems at individual building sites.Policy 4. The member cities are to require erosion control plans for land development andconstruction work that will disturb one or more acres of land. Local watershedmanagement plans and city ordinances are to include the requirements and proceduresfor reviewing, approving and enforcing the erosion control plans.Policy 5. The member cities must adopt, administer, implement and enforce ordinancesaddressing erosion and sediment control, including the permitting and inspection of suchcontrols. The BDWMO suggests that the cities use the MPCA’s model ordinance, whichcovers overall stormwater management. The cities can raise the additional moneyneeded for inspection and enforcement through building permit fees, escrow charges,performance bonds, letters of credit, etc., according to city ordinance and/or developer’sagreements.Policy 6. Point discharges of stormwater to open channels or detention basins shall beconstructed in a manner that minimizes erosion.Policy 7. Effective energy dissipation design should be provided at all conveyance systemdischarge points to prevent bank, channel or shoreline erosion.Policy 8. Design of stream bank stabilization and streambed control measures shouldconsider unique or special site conditions, energy dissipation potential, adverse effects,preservation of natural processes and habitat, and aesthetics in addition to standardengineering and economic criteria.Wetland Management PoliciesThe BDWMO’s goals regarding wetland management are to:Preserve wetlands for water retention, recharge, soil conservation, habitat, aesthetics,and natural enhancement of water quality.Lakeville Water Resources Management Plan Page 5-99

Achieve no net loss of wetlands in the BDWMO, in conformance with the MinnesotaWetland Conservation Act (WCA) and associated rules (Minnesota Rules 8420).To achieve these goals, the BDWMO set the respective roles of the BDWMO and the cities inwetland management. Through local governments implementing the standards and criterialisted in this plan, the wetlands in the BDWMO will be protected from the detrimental effectsof erosion, sedimentation, and other non-point source pollutants.Policy 1. The BDWMO will not seek to manage individual wetlands since the member cities(not the BDWMO) are the local governmental units (LGUs) responsible for administeringthe Wetland Conservation Act and rules. The member cities may request that theBDWMO classify and set goals for certain wetlands; the BDWMO commissioners willdecide whether to take on the responsibility.Policy 2. The BDWMO member cities will develop wetland protection ordinances by 2005,based on comprehensive wetland management plans and wetland functions and valuesassessments.Policy 3. The member cities should use similar wetland management systems to effectivelymanage the wetlands within the BDWMO. The member cities must adopt a wetlandmanagement system that takes into account the susceptibility of the wetlands todegradation by stormwater inputs. The BDWMO recommends that the wetlandmanagement system also take into account wildlife habitat and aesthetic preservation.The following are the BDWMO’s suggested ranges for selected wetland managementstandards: Buffer strip width: 15 feet minimum (lowest protection level) to 100 feetmaximum (highest/rarest protection level) Water level bounce for 10-year storm event: from 0 feet above existing flood level(highest protection level) to unlimited amount above existing flood level (mostdegraded/lowest protection level) Runout control (changes to existing outlet elevation): from 0 feet above existing(highest protection level) to 4.0 feet above existing (lowest protection level) Upstream stormwater treatment (when not otherwise provided): water qualitytreatment volume (dead storage) equivalent to the runoff generated by 0.5-inch24-hour storm (lowest protection level) to 2.5-inch 24-hour storm (highestprotection level)Policy 4. The LGUs must protect wetlands from impacts (i.e. filling or draining) in thefollowing order: avoid, minimize, mitigate. Mitigation of unavoidable wetland impactsmust be accomplished through restoration (first priority), enhancement (secondpriority), or wetland creation (third priority).Recreation, Habitat and Shoreland Management PoliciesLakeville Water Resources Management Plan Page 5-100

The BDWMO’s goal is to protect and enhance fish and wildlife habitat and recreationopportunities, and maintain shoreland integrity.Policy 1. The BDWMO recommends that cities encourage public and private landowners tomaintain wetlands and open space areas for the benefit of wildlife. Suitable habitat is keyto supporting fish and wildlife populations, and such habitat can be provided incidentallyto other activities.Policy 2. The BDWMO will promote and encourage protection of non-disturbed shorelandareas and restoration of disturbed shorelines and streambanks to their natural state asmuch as possible.Policy 3. The BDWMO encourages the preservation of streambank and lakeshore vegetationduring and after construction projects.Policy 4. The BDWMO encourages the creation of a buffer zone along shorelines wherenatural vegetation is maintained. These “lakescaping” techniques provide wildlifehabitat and help improve water quality.Policy 5. The BDWMO encourages the cities to identify, rank and map disturbed shorelandareas. Shoreland areas include streambanks and lakeshore areas. The cities will berequired to address this issue in their local water management plans.Policy 6. The BDWMO encourages the cities to maintain, enhance, or provide new habitat aspart of wetland modification, stormwater facility construction, or other appropriateprojects.Policy 7. The BDWMO encourages the cities to incorporate into proposed projectsalternative landscape designs that:a) increase beneficial habitat, wildlife and recreational uses; promote infiltration andvegetative water use; andb) decrease detrimental wildlife uses (such as beaver dams, goose overabundance)that damage water control facilities, shoreline vegetation, water quality orrecreational facilities.Policy 8. The cities are to maintain control and responsibility for shoreland regulation. Thecities are required to adopt DNR-approved shoreland ordinances, in accordance with theDNR’s priority phasing list.Education and Public Involvement PoliciesThe BDWMO’s goal regarding education and public involvement is to provide the public withdata they need to protect water resources and make wise decisions affecting water resources.To assist in achieving this goal, the BDWMO considers the public as their client andcategorizes “the public” into the following groups:Lakeville Water Resources Management Plan Page 5-101

Local Government—examples include city councils, city commissions (i.e. planningcommissions, environmental commissions), and the county boardsLocal citizens—examples include lake associations, the general population, subwatershedgroups, garden clubsAgencies—examples include the Minnesota Department of Transportation (MnDOT),Dakota County Office of Planning, the Minnesota Pollution Control Agency (MPCA),and the Metropolitan (Met) CouncilSchools—examples include high schools, junior high/middle schools, and elementaryschools.The types of information to be provided include water quality data, lake water level data,landscaping and lakescaping concepts, construction, development and redevelopment issuesand information, and education topics such as hydrology and rainwater gardens.Policy 1. The BDWMO recommends that the city engineers/public works officials continue toattend the BDWMO Commission meetings, if/when they are no longer commissioners, toprovide technical advice and information to the Commission.Policy 2. The BDWMO will coordinate its education efforts with the Dakota CountyEnvironmental Education Program.Policy 3. The BDWMO will coordinate and communicate with lake homeowner associationsand other appropriate citizen groups. Communication efforts could include mailingBDWMO annual reports, report cards, meeting notices, and meeting agendas to thesegroups.Policy 4. The BDWMO will send meeting notices, agendas and minutes to the technical staffof the member cities and the various agency representatives. The BDWMO encouragesthe city technical staff and the agency representatives to attend the BDWMO meetingsand provide the BDWMO with updates and provide input on technical issues. This willbe done in place of maintaining a formal Technical Advisory Committee.Policy 5. The BDWMO will form advisory committees on an as-needed basis.Policy 6. Local watershed management plans are to describe the city’s current and proposededucation efforts regarding water and natural resource management. To conform withthe NPDES Phase II rules, the BDWMO member cities will need to develop andimplement programs for public education, outreach, involvement and participation.Policy 7. The BDWMO will publish an annual newsletter summarizing its activities for publicdistribution (required).Policy 8. The BDWMO will create an Internet web site and put data (e.g. water quality,water level) and the watershed management plan (or the executive summary) on the site.Lakeville Water Resources Management Plan Page 5-102

Policy 9. The BDWMO and the member cities will disseminate other information to thepublic regarding the BDWMO, its water resources, stormwater management, etc. Listedbelow are some of the methods that could be used, ranked from least active to mostactive.a) Provide data to agencies upon request; for example, provide MnDOT with lakeand pond water quality data in anticipation of highway work, and provide MPCAand Met Council with water quality data to enter into database.b) Make reports to target audiences upon request; for example, report to asubwatershed group on the water quality of their lake.c) Collect and distribute information from other groups; for example distribute toaffected residents information from MnDOT regarding road construction and theeffect of the work on the BDWMO water resources.d) Make presentations to schools, political clients, and/or citizens groups.Groundwater PoliciesThe BDWMO will cooperate with the various agencies to protect and manage groundwater inthe watershed. The BDWO goals are to protect the quality and quantity of groundwaterresources.Policy 1. The BDWMO member cities are to encourage groundwater recharge and protectrecharge areas from potential sources of contamination. The cities should also provideincreased green space, native vegetation, and pond “dead” storage wherever possible andappropriate, to allow for the infiltration of stormwater runoff and promote groundwaterrecharge, except in areas where the groundwater is highly susceptible to contaminationfrom surface water infiltration (e.g. sensitive groundwater recharge areas).Policy 2. The BDWMO encourages its member cities to use grassed waterways to maximizeinfiltration, where feasible and not detrimental to groundwater supplies.Policy 3. Each BDWMO member city is to maintain updated records of all known on-siteseptic systems, and prohibit installation of new individual sewer systems or alteration,repair or extension of existing systems when it is feasible to connect to the city’s sanitarysewer system. The cities are to notify property owners with on-site septic systems thatthey are required to connect to the cities’ sanitary sewer, if available and feasible. Thecities are to also develop management programs and ordinances for individual sewagetreatment systems (ISTS) that are consistent with MPCA Rules 7080 and MetropolitanCouncil policies. Such management programs need to require inspection of ISTS every 3years and include policies for dealing with failing ISTS or ISTS found to be imminentpublic health threats.Policy 4. The BDWMO member cities should work with Dakota County in efforts to promoteawareness of groundwater resource issues through public education and informationprograms.Lakeville Water Resources Management Plan Page 5-103

Policy 5. The BDWMO and its member cities will support the policies in the Dakota Countygroundwater plan.Policy 6. The BDWMO and its member cities will cooperate with Dakota County and theDNR to protect sensitive groundwater areas.Standards and CriteriaThe BDWMO adopted standards and criteria to assist the BDWMO and the member cities inreaching their water resource goals. The BDWMO will work with the cities to implement theBDWMO standards within the BDWMO.Policy 1. The BDWMO standards and criteria, or an approved equivalent, must beincorporated into each city’s local watershed management plan. If the interim periodbetween approval of the BDWMO plan and a local (city) plan is anticipated to be longerthan 2 years, the BDWMO expects that member city will implement the standards within2 years of approval of the BDWMO plan.Policy 2. The BDWMO member cities are to require developers and other project proposersto prepare and implement a Runoff Control Plan and an Erosion and Sediment ControlPlan for the work, along with plans, specifications, and computations that demonstratecompliance with applicable city/BDWMO standards for runoff treatment. These plansmust be submitted before commencement of construction or reconstruction.Policy 3. The BDWMO member cities are to implement the BDWMO standards, includingpreparation of runoff and erosion control plans, for all projects that disturb one or moreacres of land.Policy 4. The BDWMO will provide technical review of projects, if requested, as a service tothe member cities.Runoff Control Plans shall meet the following criteria: The peak rate of stormwater runoff from the developed subwatershed of the site shall notexceed the existing peak rate of runoff for the 5-year (or 10-year) and the 100-year returnfrequency critical duration storm events. For the purposes of this criteria,“subwatershed” may be the project site, or may be an area of greater size for which anapproved local water management plan meets this criteria. A hydrograph method based on sound hydrologic theory shall be used to analyzestormwater runoff for the design or analysis of flows in conveyors, streams, and channelsand flows to ponds and wetlands. Reservoir routing procedures and critical duration 100-year runoff events shall be usedfor design of detention basins and outlets.The size and design considerations for regional and on-site detention and treatment facilitiesare dependent on the imperviousness of the development and the degree to which infiltrationLakeville Water Resources Management Plan Page 5-104

of runoff is encouraged. Design of detention and treatment basins as described in the site’sRunoff Control Plan shall incorporate recommendations from the Nationwide Urban RunoffProgram (NURP) and Protecting Water Quality in Urban Areas (MPCA, 2000), or otherapplicable publications. Project proposers should note that use of wet-detention basins aswetland mitigation sites is not permitted unless the design follows the relevant section of theMinnesota Wetland Conservation Act (see MN Rules 8420.0540 Subp. 10.B). The BDWMOadopted the following design criteria to meet water quality goals for water resources. Aswater quality data, modeling and studies are completed, these criteria may be revised. Theyare not intended to restrict the design process associated with proposed projects within theBDWMO, but they are minimum requirements the cities must adopt for use during theirproject review process.The following design criteria for detention and treatment basins were developed based onNURP standards and meet the Metropolitan Council’s Model Storm Water ManagementOrdinance and Interim Guidelines design standards. Cities must incorporate these designcriteria into their local water management plans and official controls (ordinances, permitreview guidelines, etc.).1. A permanent pool (“dead storage”) volume below the outlet elevation shall be providedwhich is greater than or equal to the runoff from a 2.5-inch 24-hour storm over theentire subwatershed for regional basins, or over the project site for on-site basins,assuming full development.2. A permanent pool average depth (basin volume/basin area) that is > 4 feet, with amaximum depth of < 10 feet.3. An emergency spillway (emergency outlet) adequate to control the 100-year frequencycritical duration rainfall or runoff event.4. Basin side slopes above the outlet elevation should be no steeper than 3:1 whenpossible, and preferably flatter. A basin shelf with a minimum width of 10 feet and 1-foot deep below the outlet elevation is recommended to enhance wildlife habitat,reduce potential safety hazards, and improve access for long-term maintenance.5. To prevent short-circuiting, the distance between the major inlets and the outlet shallbe maximized.6. A sufficient flood pool (“live storage”) volume above the outlet elevation shall beprovided so that the peak discharge rate from the 100-year frequency, criticalduration storm is not greater than the peak discharge for a similar storm andpredevelopment watershed conditions.7. Extended detention of runoff from the more frequent (1-year to 5-year) storms shall beprovided that detains the runoff hydrograph at least 24 hours. This can be achievedby designing the outlet to include a perforated vertical riser, a small orifice outlet or amultiple -stage outlet.8. If possible, the basin outlet should be designed to allow the basin to be drained forsediment removal.9. Effective energy dissipation devices which reduce outlet velocities to 4 fps or less shallconsist of stilling basins or other such measures to prevent erosion at all stormwateroutfalls into the basin and at the detention basin outlet.Lakeville Water Resources Management Plan Page 5-105

10. Trash and floatable debris skimming devices shall be placed on the outlet of all onsitedetention basins to provide treatment up to the critical duration 5-year stormevent. These devices can consist of baffled weirs, submerged outlets or other suchmeasures. Velocities through baffled weir devices shall be less than 0.5 fps.Evaluation and Accountability PoliciesThe BDWMO will work with member cities to set reasonably attainable goals and measurableexpectations and to assess the BDWMO’s and each city’s progress toward the agreed uponexpectations.Policy 1. The BDWMO and the member cities will identify and prioritize initiatives thatsupport outcome based goals. Examples of outcome-based goals include phosphoruslimits for specific water resources, implementation of best management practices,education programs, maintenance activities, etc. The cities and the BDWMO will setexpectations of performance in terms of effort and schedule.Policy 2. Every year, the BDWMO and the cities will meet to discuss progress on the goals setthe previous year. The cities should also make regular reports to the BDWMOCommission throughout the year regarding progress. The progress will be reported backto the citizens. Successes will be celebrated and failures will be brought to the attentionof the policy makers to encourage the meeting of the BDWMO goals. The BDWMO willwork to support the staff and elected officials to meet the agreed upon expectations.Policy 3. The BDWMO and the cities will use a two-track evaluation concept that includestrend analysis and performance analysis. The trend analysis will demonstrate waterquality and other significant trends at selected lakes and ponds. The performanceanalysis will evaluate the implementation of maintenance plans, capital improvementplans, and other items.a) Trend Analysis. The BDWMO will track water quality trends in Crystal Lake, KellerLake, Orchard Lake, Kingsley Lake, Lac Lavon, and Sunset Pond (the BDWMOstrategic resources), using the water quality data they collect for these lakes andponds. The water quality data and trends will be compared to the BDWMO’s waterquality goals and reported to the public. The cities will collect water qualitymonitoring data and track trends for other selected water bodies in theircommunities. The water quality data and trends will be compared to the cities’ waterquality goals and reported to the BDWMO and citizens. The BDWMO will also trackthe aesthetic and habitat data collected for the BDWMO strategic resources.b) Performance Analysis. The BDWMO will work with the member cities to set goalsand a schedule for completion of implementation tasks. The member cities are toincorporate the BDWMO requirements/standards into their ordinances/policies.Based on policies stated in other parts of this plan, the cities are expected to completethe following implementation tasks:Lakeville Water Resources Management Plan Page 5-106

Manage non-strategic water bodies to achieve the cities’ goals, includingclassifying, monitoring, tracking trends, conducting studies, and implementingother lake water quality actions.Monitor of non-strategic Category I and Category II water bodies.Set water quality action levels in local plans for Category I and Category II lakes.Implement best management practices during development.Require stormwater management upgrades resulting from redevelopment toconform to the policies in this plan.Request project proposers consider methods for reducing impervious coverage.Restrict the Orchard Lake outlet to maintain post-development discharge ratesleaving the BDWMO (tributary to the Credit River) at or below the predevelopmentrates.Maintain discharge rates from subwatersheds tributary to the Credit River either:(1) at or below predevelopment rates, for undeveloped subwatersheds; or (2) atexisting rates, for fully developed subwatersheds.Maintain discharge rates leaving the BDWMO and entering the Lower MinnesotaRiver Watershed District either: (1) at or below predevelopment rates, forundeveloped subwatersheds; or (2) at existing rates, for fully developedsubwatersheds.Require erosion control and runoff control plans for work that will disturb morethan one acre of land.Secure easements or fee title to the stormwater system, as areasdevelop/redevelop.Provide pretreatment of stormwater prior to its discharge to wetlands and otherwater resources (for new discharges). Pretreatment at existing direct dischargepoints can be accomplished as part of road reconstruction and other projects,through addition of detention ponds, grit chambers, diversion to existing ponds,etc.Develop and implement a maintenance program for the city’s stormwater system,including tasks such as street sweeping, pond inspections, catch basin cleaning,and excavation of accumulated sediments.Prepare and adopt a local watershed management plan that conforms to theBDWMO plan, within 2 years of BWSR’s approval of the last WMO plan thataffects the city.Include in city ordinances the requirements for preparation of erosion controlplans, in addition to runoff water management plans.Adopt, administer, implement and enforce ordinances addressing erosion andsediment control, including permitting and inspections.Develop wetland protection ordinances by 2005, based on a comprehensivewetland management plan and a wetland functions and values assessment.Inventory, classify, and determine wetland functions and values on an as-neededbasis, prior to development of a comprehensive wetland management plan.Protect wetlands from impacts.Lakeville Water Resources Management Plan Page 5-107

Maintain control and responsibility for shoreland regulation, including adoptionof DNR-approved shoreland ordinances, when required.Provide information to the public regarding the BDWMO, its water resources,stormwater management, etc..Maintain updated records of on-site septic systems and prohibit installation,repair, etc. when connection can be made to the city’s sanitary sewer system.Implement the BDWMO standards and criteria in Section 5.9 within 2 years of the BDWMOplan approval, if a local watershed plan will not be completed within 2 years of the BDWMOplan approval.5.13.2.3 Capital Improvement Program (CIP) DataThe BDWMO Budget and Implementation program information is available at:http://www.dakotacountyswcd.org/watersheds/blackdogwmo/wmp.htmLakeville Water Resources Management Plan Page 5-108

Table 5.13 BDWMO Requirements for City Policies and OrdinancesTopicEasementsMinimum BuildingElevationsErosion/SedimentControl and RunoffWater ManagementWetland ManagementShoreland RegulationIndividual SewageTreatment SystemsGeneralRequirement/StandardCities to secure easements or fee title to the stormwater systemas areas develop or redevelopAdopt ordinances or policies that set minimum buildingelevations at least 1-foot above the critical 100-year floodelevation for structures adjacent to inundation areas. Citiesshould consider the effects of events larger than the 100-yearflood when setting minimum building elevations. Higherminimum building elevations should be considered for structuresadjacent to ponding areas with large tributary watersheds and forstructures adjacent to landlocked basins.Ordinances are to include requirements for the preparation oferosion control plans and runoff water management plans,which require the use of best management practices onconstruction sites, for all projects that will disturb one ormore acres of landOrdinances are to include the requirements and procedures forreviewing, approving and enforcing runoff control and erosioncontrol plansAdopt, administer, implement and enforce ordinances addressingerosion and sediment control, including the permitting andinspection of such controlsDevelop wetland protection ordinances by 2005, based oncomprehensive wetland management plan and wetland functionsand values assessment.Adopt DNR-approved shoreland ordinances, in accordance withthe DNR’s priority phasing listDevelop management programs and ordinances for individualsewage treatment systems (ISTS) that are consistent with MPCARules 7080 and Metropolitan Council policiesIf the interim period between approval of the BDWMO plan and alocal (city) plan is anticipated to be longer than 2 years, theBDWMO expects that member city will implement the standardsin Section 5.9 of the BDWMO plan within 2 years of approval ofthe BDWMO plan.Lakeville Water Resources Management Plan Page 5-109

5.14 OTHER AGENCY RESPONSIBILITIESAlong with the City of Lakeville and the Vermillion River and Black Dog Watershed ManagementOrganizations, various units of government are involved in regulating water resource relatedactivities as follows.Dakota CountyCounties (including Dakota County) have a wide variety of duties, including propertyassessment, record-keeping, road maintenance (including street sweeping, and snow/icecontrol), administration of election and judicial functions, social services, corrections, childprotection, library services, hospitals and rest homes, public health services, planning andzoning, economic development, parks and recreation, water quality, and solid wastemanagement and recycling (including yard waste and compost sites). The counties’responsibilities directly related to the city include: Levying taxes for the City Construction and maintenance of county highways/roads Groundwater management, including preparing and adopting groundwater plans (see theDakota County Groundwater Protection Plan, 2000) Adopting and implementing the county’s MS4 SWPPPMore information is available at the Dakota County website:http://www.co.dakota.mn.us/default.htmThe Metropolitan CouncilThe Metropolitan Council provides regional planning and wastewater services (collection andtreatment) for the seven-county metropolitan area. The Metropolitan Council provides reviewand comment on watershed management plans, local water management plans, and localcomprehensive (land use) plans; conducts lake monitoring (including the Citizen AssistedMonitoring Program); and conducts river and stream monitoring. Questions concerning theMetropolitan Council’s role in water resource management should be directed to theMetropolitan Council, 390 North Robert Street, St. Paul, MN 55101, (651-602-1000).More information is available at the Metropolitan Council website: www.metrocouncil.orgMinnesota Department of Natural Resources (MDNR)The MDNR Division of Waters (Waters) manages water resources through a variety of programsin its Water Management section, Surface Water and Hydrographics section, and Ground Waterand Climatology section. MDNR Waters administers the public waters work permit program,the water appropriation permit program, and the dam safety permit program. MDNR Fisheriesadministers the aquatic plant management control permit program and other fishery relatedpermits.Lakeville Water Resources Management Plan Page 5-110

In addition to permit programs, the MDNR oversees the floodplain management program, thepublic waters inventory program, the shoreland management program, the flood damagereduction grant program, the wild and scenic rivers program, various surface and groundwatermonitoring programs, and the climatology program. The MDNR is involved in enforcement ofthe Wetland Conservation Act (WCA) and is responsible for identifying, protecting, andmanaging calcareous fens.The MDNR’s public waters work permit program (Minnesota Statutes 103G) requires a MDNRpublic waters permit for work below the Ordinary High Water level (OHWL) that will alter ordiminish the course, current, or cross-section of any public waters or public waters wetlands,including lakes, wetlands and streams. For lakes and wetlands, the MDNR’s jurisdiction extendsto designated U.S. Fish and Wildlife Service Circular #39 Types 3, 4, and 5 wetlands which are10 acres or more in size in unincorporated areas, or 2.5 acres or more in size in incorporatedareas. The program prohibits most filling of public waters and public waters wetlands for thepurpose of creating upland areas. The public waters work permit program was amended in 2000to reclassify public waters and to make the administrative program more consistent with theWCA administrative program. Under certain conditions, work can be performed below theOHWL without a public waters work permit. Examples include docks, watercraft lifts, beachsand blankets, ice ridge removal/grading, riprap, and shoreline restoration.The MDNR regulates groundwater usage rate and volume as part of its charge to conserve anduse the waters of the state. For example, suppliers of domestic water to more than 25 people orapplicants proposing a use that exceeds 10,000 gallons per day or 1,000,000 gallons per yearmust obtain a water appropriation permit from the MDNR. Appropriation permits from theMDNR are not required for domestic uses serving less than 25 persons for general residentialpurposes. The MDNR is also responsible for mapping sensitive groundwater areas, conductinggroundwater investigations, addressing well interference problems, and maintaining theobservation well network.More information is available at the MDNR website: www.dnr.state.mn.usMinnesota Board of Water and Soil Resources (BWSR)BWSR oversees the state’s watershed management organizations (joint powers, county andwatershed district organizations), oversees the state’s Soil and Water Conservation Districts, andadministers the rules for the WCA and metropolitan area watershed management.More information is available at the BWSR website: www.bwsr.state.mn.usMinnesota Pollution Control Agency (MPCA)The MPCA administers the State Discharge System/National Pollutant Discharge EliminationSystem (NPDES) Permit program (point source discharges of wastewater), the NPDES GeneralStormwater Permit for Construction Activity, the NPDES General Industrial Stormwater Permitprogram, the NPDES Phase I and Phase II Storm Water Permit program, and the individualsewage treatment system regulations (7080 Rules). The MPCA also reports the state’s “impairedLakeville Water Resources Management Plan Page 5-111

waters” to the U.S. Environmental Protection Agency. Spills should be reported directly to theMPCA.The Minnesota Pollution Control Agency (MPCA) administers and enforces laws relating topollution of the state’s waters, including groundwater. The MPCA monitors ambientgroundwater quality, and administers septic system design and maintenance standards. TheTanks and Spills Section of the MPCA regulates the use, registration and site cleanup ofunderground and above ground storage tanks.The MPCA is responsible for administering the programs regulating construction andreconstruction of individual sewage treatment systems (ISTS). The MPCA requires an inspectionprogram for ISTS that meets MPCA standards. Minnesota Rules 7080 govern administrationand enforcement of new and existing ISTS. Hennepin County’s Ordinance 19 also sets standardsfor ISTS and adopts by reference Minnesota Rules 7080.The MPCA is responsible for administering the programs regulating construction andreconstruction of ISTS. The MPCA requires an inspection program for ISTS that meets MPCAstandards. Minnesota Rules 7080 govern administration and enforcement of new and existingISTS.The MPCA no longer administers Section 401 of the Clean Water Act Water Quality Certificationprogram, which means the MPCA no longer evaluates 401 applications for conformance withwater-quality standards, and the MPCA has waived its 401 authority in most cases. However,formal applications for 401 certification must still be sent to the MPCA.More information is available at the MPCA website: www.pca.state.mn.usMinnesota Department of Health (MDH)The MDH is the official state agency responsible for addressing all environmental healthmatters, including groundwater protection. The MDH administers the Well ManagementProgram, the Wellhead Protection Program, and the Safe Drinking Water Act rules. The MDHalso issues fish consumption advisories. The MDH is responsible for preventing pollution ofwater supplies to ensure safe drinking water sources and limit public exposure to contaminants.Through implementation of the federal Safe Drinking Water Act, the MDH conducts the PublicWater Supply Program, which allows the MDH to monitor ground water quality and train watersupply system operators. The 1996 amendments to the federal Safe Drinking Water Act requirethe MDH to prepare source water assessments for all of Minnesota’s public water systems and tomake these assessments available to public.Through its Well Management Program, the MDH administers and enforces the MinnesotaWater Well Code, which regulates activities such as well abandonment and installation of newwells. The MDH also administers the Wellhead Protection Program, which is aimed atpreventing contaminants from entering the recharge zones of public water supply wells.Lakeville Water Resources Management Plan Page 5-112

In 1997, the Wellhead Protection Program rules (Minnesota Rules 4720.5100 to 4720.5590)went into effect. These rules require all public water suppliers that obtain their water from wellsto prepare, enact and enforce wellhead protection plans. The MDH prepared a prioritizedranking of all such suppliers in Minnesota. Regardless of the ranking, Rules 4720 require allpublic water suppliers to initiate wellhead protection measures for the inner wellheadmanagement zone prior to June 1, 2003. If a city drills a new well and connects it to thedistribution system, the city must begin development of a wellhead protection plan. Wellheadprotection plans include: delineation of groundwater “capture” areas (wellhead protectionareas), delineation of drinking water supply management areas (DWSMA), assessment of thewater supply’s susceptibility to contamination from activities on the land surface, andmanagement programs, such as identification and sealing of abandoned wells, andeducation/public awareness programs. As part of its role in wellhead protection, the MDHdeveloped the guidance document “Evaluating Proposed Stormwater Infiltration Projects inVulnerable Wellhead Protection Areas” (MDH, 2006).See the MDH website (http://www.health.state.mn.us/divs/eh/water/index.html ) for moreinformation about these programs.Minnesota Environmental Quality Board (EQB)The EQB administers the state’s environmental review program, including EnvironmentalAssessment Worksheets (EAW) and Environmental Impact Statements (EIS).More information is available at the EQB website: www.eqb.state.mn.usU.S. Army Corps of Engineers (COE)The COE administers the Section 10 of the Rivers and Harbors Act permit program, and theSection 404 permit program.Section 404 - Authorizations. The Federal Clean Water Act requires that anyone who wants todischarge dredged or fill material into U.S. waters including wetlands must first obtain aSection 404 permit from the U.S. Army Corps of Engineers. Examples of activities that require aSection 404 permit include: construction of boat ramps, placement of riprap for erosionprotection, placing fill in a wetland, building a wetland, construction of dams or dikes, streamchannelization, and stream diversion.When Section 404 permit applications are submitted to the Corps of Engineers, the applicationsare typically posted for the U.S. Fish and Wildlife Service, the U.S. Forest Service, the U.S. EPA,and other federal agencies to review and provide comments on the application. The Corps ofEngineers evaluates permit requests for the potential impact to various functions and values ofthe wetland.Section 401 - Water Quality Certifications. A Section 401 water quality certification may begranted if the applicant demonstrates that the proposed activity “will not violate Minnesota’swater quality standards or result in adverse long-term or short-term impacts on water quality.”Greater protection is given to a category of waters designated as Outstanding Resource ValueLakeville Water Resources Management Plan Page 5-113

Waters. The waters in this category have received this designation because of their exceptionalvalue. These waters include such groups as scientific and natural areas, wild, scenic andrecreational river segments and calcareous fens.More information is available at the COE website: www.usace.army.milLakeville Water Resources Management Plan Page 5-114

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31Barr Footer: Date: 5/14/2008 12:24:14 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section5\Figure_5_4 Wetland Classifications.mxd User: arm2Orchard Lake4567 23185TH ST W§¨¦ 35 4567 9456 70Lake Marion4567 50IPAVA AVEDODD BLVDCEDAR AVE202ND ST W215TH ST W190TH ST WPILOT KNOB RDFigure 5.4.1WETLAND CLASSIFICATIONSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryWetland ClassificationManage 1Manage 2PreserveI3,500 1,750 0 3,500Feet750 375 0 750 1,500MetersRestoreSouth CreekUtilizeStorm PondUnclassifiedData Sources: City of Lakeville, Dakota County Soil and Water, MN DNR,MnDOT, City of Lakeville Wetland Management Plan (2003).Imagery Source: Aerials Express, 2006.

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake4567 31Barr Footer: Date: 5/14/2008 12:26:22 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section5\Figure_5_13_Watersheds.mxd User: arm2Orchard LakeBlack Dog WatershedManagement Organization4567 23185TH ST W§¨¦ 35 Vermillion River Watershed Joint Powers Organization456 70Lake Marion4567 50IPAVA AVE215TH ST W4567 9DODD BLVDSouth CreekNorth Branch of South Creek202ND ST WCEDAR AVEEast Branch of South Creek190TH ST WSouth Branch of South CreekNorth CreekPILOT KNOB RDFigure 5.13.1WATERSHEDSCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel BoundaryStreamsLakesWatershed DivideImagery Source: Aerials Express, 2006.Data Sources: City of Lakeville, Minnesota DNR, MnDOT.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

6.0 Assessment of Issues and Opportunities6.1 WATER QUALITY PROBLEMS AND ISSUES6.1.1 Stormwater Runoff Quality IssuesPollutants are discharged to surface waters as either point sources or non-point sources. Pointsource pollutants discharge to receiving surface waters at a specific point from a specificidentifiable source. Discharges of treated sewage from a wastewater treatment plant or from anindustry are examples of point sources. Unlike point sources, non-point source pollution cannotbe traced to a single source or pipe. Instead, pollutants are carried from land to water instormwater or snowmelt runoff, in seepage through the soil, and in atmospheric transport. Allthese forms of pollutant movement from land to water make up non-point source pollution.For lakes, ponds, and wetlands, phosphorous istypically the pollutant of major concern. Pointsources of phosphorus typically come frommunicipal and industrial discharges to surfacewaters, whereas non-point sources ofphosphorus come from urban runoff,construction sites, individual sewage treatmentsystems (ISTS), and, in agricultural areas, fromfields and feedlots. Point sources frequentlydischarge continuously throughout the year,while non-point sources (with the exception ofISTS) discharge in response to precipitation orsnowmelt events.POLLUTANTSPoint Source vs. Non-Point SourcePoint source pollutants discharge tosurface waters at a specific point from aspecific identifiable source.Non-point source pollution cannot betraced to a single source or pipe. Instead,pollutants are carried from land to water instormwater or snowmelt runoff, in seepagethrough the soil, and in atmospherictransportFor most water bodies, non-point source runoff, especially stormwater runoff, is a majorcontributor of phosphorus. As urbanization increases and other land use changes occur in thecity, nutrient and sediment inputs (i.e., loadings) from stormwater runoff can far exceed thenatural inputs to the city’s water bodies. In addition to phosphorus, stormwater runoff maycontain pollutants such as oil, grease, chemicals, nutrients, metals, litter, and pathogens, whichcan severely reduce water quality.Land use changes resulting in increased imperviousness (e.g., urbanization) or land disturbance(e.g., urbanization, construction or agricultural practices) also result in increased amounts ofphosphorus carried in stormwater runoff. In addition to watershed (stormwater runoff) sources,other possibly significant sources of phosphorus include atmospheric deposition, internalloading (e.g., release from anoxic sediments, algae die-off, aquatic plant die-back, and fishdisturbed sediment), and failing ISTS.Lakeville Water Resources Management Plan Page 6-1

As phosphorus loadings increase, it is likely that water quality degradation will accelerate,resulting in unpleasant consequences, such as profuse algae growth or algal blooms. Algalblooms, overabundant aquatic plants, and the presence of nuisance/exotic species, such asEurasian watermilfoil, purple loosestrife, and curlyleaf pondweed, interfere with ecologicalfunction as well as recreational and aesthetic uses of water bodies. Phosphorus loadings mustoften be reduced to control or reverse water quality degradation.The Minnesota Pollution Control Agency’s (MPCA) Stormwater Program is designed to reducethe pollution and damage caused by stormwater runoff. Mandated by Congress under the federalClean Water Act, the National Pollutant Discharge Elimination System (NPDES) StormwaterProgram is a national program for addressing polluted stormwater runoff. Minnesota regulatesthe disposal of stormwater through State Disposal System (SDS) permits. The MPCA issuescombined NPDES/SDS permits for construction sites, industrial facilities and municipal separatestorm sewer systems (MS4s). Through the MPCA’s MS4 program, the City of Lakeville isrequired to obtain a NPDES Phase II (MS4) Storm Water permit.Current City standards require implementation of water quality treatment best managementpractices for development projects, but in the future, the City may need to achieve higher levelsof water quality treatment than is currently required.6.1.2 NPDES Storm Water Pollution Prevention Plan (SWPPP)The City of Lakeville is included in a group of communities with populations greater than 10,000that are federally required to obtain a Municipal Separate Storm Sewer System (MS4) permit formanaging non-point source storm water. The Phase II NPDES permitting process requires citiessuch as Lakeville to file a Phase II NPDES permit with the Minnesota Pollution Control Agency(MPCA), which addresses how the City will regulate and improve storm water discharges. Thepermit must include a SWPPP addressing all of the requirements of the permit.The Lakeville Environmental Resources Department has managed the permit applicationprocess, including identifying issues and developing implementation measures to address theissues. The framework for developing the City’s NPDES Phase II permit application and planwas the City’s former Comprehensive Surface Water Management Plan (SWMP), adopted in1995. Lakeville’s NPDES Phase II SWPPP addresses six minimum control measures (MCMs)outlined in the permit requirements. Many of the best management practices (BMP) required inthe NPDES permit have already been developed and are in place. The six MCMs required by thepermit are:1. Public outreach and education2. Public participation/involvement3. Illicit discharge detection and elimination4. Construction site runoff control5. Post-construction runoff control6. Pollution prevention/good housekeepingLakeville Water Resources Management Plan Page 6-2

The SWPPP identifies issues related to the above minimum measures and more. It is designed toaddress these issues thereby minimizing the discharge of pollutants into the City’s storm watersystem, protecting and enhancing water quality, and satisfying the appropriate requirements ofthe Clean Water Act of 1984 and as amended. The complete Lakeville SWPPP is presented inAppendix C.6.1.3 Non-Degradation ReportThe Minnesota Pollution Control Agency (MPCA) revised the General NPDES/SDS PermitMNR040000 (Permit) for the city of Lakeville to discharge storm water associated with MS4s,effective June 1, 2006. Lakeville has completed a SWPPP to address the six minimum controlmeasures required by the previous permit. The non-degradation report was developed toaddress modifications to the SWPPP for measures that may be necessary to meet the new,applicable requirements of Appendices C and D in the re-issued permit. Appendix C coversdischarges to trout waters and wetlands that are applicable to the city of Lakeville. Appendix Dcovers the non-degradation requirements for Selected MS4s (30 permittees including the city ofLakeville), including the development of a loading assessment and non-degradation report. Thecomplete Lakeville Loading Assessment and Nondegradation Report is presented in AppendixD of this plan.For the loading assessment, the Simple Method was used to determine the pollutant loadingsand runoff volumes from each of the land uses within each watershed and the P8 Model was usedto account for the effects of BMP implementation for the time periods of interest in the permitconditions. The loading assessment modeling results were summarized for each of the city’s sixmajor watersheds to show the Simple Method loading and volume estimates for each timeperiod, as well as the loading and volume estimates after applying the P8 model design criteriafor BMP implementation, based on the ordinances and design standards that were in place whenthe various developments occurred.The results show that, without BMPs, the total average annual flow volume from the city hasincreased significantly since 1988 and would continue to increase substantially by 2020, withoutimplementation of infiltration practices. Following implementation of BMPs the overall averageannual flow volume from the city in 2020 is 40 percent higher than the flow volume estimatefrom 1988 but continued implementation of infiltration practices will offset the increases in flowvolume between 2006 and 2020 and result in an overall flow volume reduction of more than 7percent, compared to the volume estimate for 2006.Development within the lake watersheds of the city between 1988 and 2006 account forapproximately 56% of the overall average annual flow volume increase between 1988 and 2020.Implementation of infiltration practices should maintain the average annual flow volumeincreases in the creek watersheds of the city to 26% of the 1988 combined volume for the samewatersheds. The loading assessment indicates that implementation of watershed BMPs, in theLakeville Water Resources Management Plan Page 6-3

past and planned for the future, will ensure that the TP and TSS loads from the city will notincrease between 1988 and 2020.The loading assessment and non-degradation report were completed assuming that future BMPimplementation would follow the Vermillion River Watershed Joint Powers OrganizationStandards (VRWJPO, 2006) for most of the city, with the exception of the South Creekwatershed, which would continue to follow the more stringent volume control requirementsestablished in the City of Lakeville South Creek Management Plan.As a result, the City will update its development review policies, standards and procedures, ascited in the SWPPP. This approach will ensure the following:Receiving water quality should be improved for lakes, wetlands and streams inLakevilleChannel erosion and stream morphology changes will be controlledFurther protection will be provided for the physical and biological integrity of thestream and wetland corridorsTemperature changes for trout streams and their tributaries will be mitigated andchanges in flow will be controlledControlled bounce and duration of inundation in the city’s wetlands and preservationof the functions and values for each type of wetland classificationWherever possible, the standards will be applied to redevelopment projects to mitigatepast increases in storm water runoff volume and further improve receiving waterquality and habitatIn addition, the SWPPP will be modified to discuss further protection for the physical andbiological integrity within the trout stream watersheds by implementing the following measures:Establishment of buffers along stream corridors, based on the most restrictiverequirements for each type of corridor in the South Creek Management Plan and theVRWJPO StandardsContinued education of landowners and residents of existing developments about theimportance of maintaining existing stream buffers and eliminating illicit dischargesEstablishing spill prevention and response procedures for industrial and municipaloperations within the watershedsIn the few projects where the requirements of the WCA are not as comprehensive as MPCA waterquality standards, then the requirements of the NPDES permit will require an LGU to make adetermination that will also satisfy Minn. R. 7050.0186. The SWPPP will show where thevulnerable wellhead protection areas are within the city and define the measures that will reduceLakeville Water Resources Management Plan Page 6-4

the threat to drinking water to the maximum extent practicable. These measures will bedeveloped in accordance with the Minnesota Department of Health’s Evaluating ProposedStorm Water Infiltration Projects in Vulnerable Wellhead Protection Areas, and the MPCA’sMinnesota Stormwater Manual guidance for potential stormwater hotspots. The City’s SWPPPwill also provide for tracking the implementation of the BMPs and actions to be taken.6.1.4 Impaired Waters and TMDL IssuesThe federal Clean Water Act (CWA) requires states to adopt water quality standards to protectthe nation’s waters. Water quality standards designate beneficial uses for each waterbody andestablish criteria that must be met within the waterbody to maintain the water quality necessaryto support its designated use(s). Section 303(d) of the CWA requires each state to identify andestablish priority rankings for waters that do not meet the water quality standards. The list ofimpaired waters, or sometimes called the 303(d) list, is updated by the state every two years.For the MPCA to list a water body (besides a river or stream) on the impaired waters list, it mustmeet the MPCA’s definition of a “lake” and there must be sufficient data to determine if the lakeis impaired (see MPCA guidance manual, 2005). The criteria used to determine if a lake isimpaired vary, according to the lake’s ecoregion. Two ecoregions cover Lakeville, the NorthCentral Hardwood Forest ecoregion (NCHF or CHF) in the western half of the City and theWestern Corn Belt Plains ecoregion (WCBP) in the eastern half. The criteria for WCBP lakes areless stringent than for NCHF lakes and are listed below (MPCA guidance manual, 2005).The MPCA defines shallow lakes as lakes with a) a maximum depth of 15 feet or less; or b) 80%or more of the lake is littoral (the percent of the lake that is 15 feet deep or less). These “shallowlakes” criteria are also included in Table 6.1.1 below.Table 6.1.1. MPCA Impaired Waters Listing Criteria*Ecoregion/Lake TypeTotal Phosphorusug/L (ppb)Water Quality ConstituentChlorophyll-aug/L (ppb)Secchi Disc(meters)North Central Hardwood ForestStream trout lakes

eceive and still meet water quality standards. A TMDL establishes the pollutant loadingcapacity within a waterbody and develops an allocation scheme amongst the variouscontributors, which include point sources, non-point sources and natural background, as well asa margin of safety. As a part of the allocation scheme a waste load allocation (WLA) is developedto determine allowable pollutant loadings from individual point sources (including loads fromstorm sewer networks), and a load allocation (LA) establishes allowable pollutant loadings fromnon-point sources and natural background levels in a waterbody.Table 6.6.2 lists the impaired waters within the City of Lakeville or impaired waters that receivestormwater downstream from the City, the affected MPCA designated use, the pollutant orstressor that is not meeting the MPCA water quality criteria, and the MPCA target for startingand completing the TMDL process.Table 6.1.2. Summary of the Impaired Waters ListWater BodyPollutant orStressorAffected MPCABeneficial UseMPCA Listing Date/TargetTMDL start/completionLee Lake(19-0029)Excess Nutrients Aquatic Recreation 2002/2006/2011Orchard Lake(19-0031)Mercury FCA Aquatic Consumption 1998/1999/2011Lake Marion(19-0026)Mercury FCA Aquatic Consumption 1998/1999/2011Crystal LakeMercury FCA Aquatic Consumption 1998/1999/2011(19-0027) Excess Nutrients Aquatic Recreation 2002/2006/2011Headwaters tounnamed Creek**“North Creek”Fecal Coliform Aquatic Recreation 2008/2012/2014(070400001-542)Unnamed creek toVermillion R.**“South Creek”Fecal Coliform Aquatic Recreation 2008/2012/2014(070400001-527)Credit River(07020012-517)Turbidity Aquatic Life 2002/2006/2010Lake Pepin(25-001)Excess Nutrients Aquatic Recreation 2002/2004/2009** Proposed for 2008 Impaired Waters ListThe Credit River is listed as impaired for turbidity. A large part of the northwestern portion ofthe City of Lakeville ultimately drains to the Credit River, including Orchard and Kingsley Lakes.Load reductions will likely be assigned to the City, based on a TMDL study. The TMDLrequirements will then be incorporated into the City’s NPDES Phase II MS4 permit. This WaterResources Management Plan will likely need to be amended to incorporate those TMDLrequirements.Lakeville Water Resources Management Plan Page 6-6

Lake Pepin is also on the impaired waters list for excess nutrients and receives runoff indirectlyfrom Lakeville via the Mississippi and Minnesota Rivers. The ongoing Lake Pepin TMDL willlikely result in load reductions requirements for the City as well. These TMDL requirements willalso likely be incorporated into the City’s NPDES Phase II MS4 permit and the WRMP.Mercury in Minnesota fish comes almost entirely from atmospheric deposition, withapproximately 90 percent originating outside of Minnesota (MPCA, 2004). Because the mainsource of mercury comes from outside the state and the atmospheric deposition of mercury isrelatively uniform across the state, the MPCA has developed a statewide TMDL for mercury of 11kg/year for the entire state.6.1.5 Metropolitan Council IssuesMunicipalities must comply with Metropolitan Council policies by adopting goals and methods toreduce non-point source pollution (Metropolitan Council, Local Planning Handbook, September2005). Doing so requires the municipality to identify and control such things as runoff fromdevelopment and construction activities. The municipality must identify ways to reducestormwater quantity and improve its quality. Information regarding the following actions shouldbe included in the local water management plan:Continue control of runoff rates so that land-altering activities, such as construction orroad building projects, do not result in an increase in peak storm water flowContinue implementation of criteria such as those of the Nationwide Urban RunoffProgram (NURP) criteria for wet detention basins to protect and improve stormwaterrunoff qualityContinue to promote a stormwater plan that increases infiltration and decreasesimpervious areasContinue implementation of management practices such as those described in theMetropolitan Council’s Urban Small Sites Best Management Practice Manual to reducestorm water runoffContinue to incorporate requirements for treatment to precede stormwater dischargeinto lakes and streamsContinue to implement methods for minimizing the effects of temperature in vulnerableenvironments such as trout streams and fensMaintain the wetland management plan that incorporates a function and valueassessment for wetlands consistent with the wetland policies of the WMOsEstablish measurable water quality goals for each body of water identified in themunicipality’s local water management and land use plans. Include information on howsurface water protection will also protect groundwater.Lakeville Water Resources Management Plan Page 6-7

Local water plans must include ordinances intended to reduce non-point source pollution. Thesemay include erosion and sediment control, storm water management, wetland protection,buffers, shoreland or flood plain protection, and critical area management ordinances.Municipalities that have one or more bodies of water identified in the MPCA’s list of impairedwaters must provide information relating to their compliance with the MPCA’s Total MaximumDaily Load (TMDL) program. Municipalities identified in Appendix A-3 of the Water ResourcesManagement Policy Plan must meet the MPCA’s National Pollutant Discharge EliminationSystem (NPDES) requirements for a Municipal Separate Storm Sewer System (MS4) permit.The Metropolitan Council policy is that there will be no adverse impact on the quality of watermoving through the region. Municipalities must adopt policies to reduce the effects ofstormwater runoff so that lakes, rivers, streams and wetlands are not degraded.The goals and policies incorporated in this plan along with the existing City programs and theplan’s implementation plan address these Metropolitan Council issues.6.1.6 City Water Quality GoalsThe City of Lakeville manages lakes differently than wetlands, so it is important to differentiatebetween the two. The City used the MPCA’s Guidance Manual for Assessing the Quality ofMinnesota Surface Waters for the Determination of Impairment (October 2005) to categorizewater bodies as lakes or wetlands. According to the guidance document, a water body is a lake ifit meets all of the following requirements: Listed in MDNR Bulletin 25 Not listed as a wetland (i.e., DNR public waters number ends in “W”) in the MDNRPublic Waters Inventory 10 acres or larger Hydraulic residence time of at least 14 daysFor the purposes of this plan, the City will consider a water body to be a lake if it is a DNR-listedpublic water, but not listed as a wetland, and 10 acres or larger in water surface area. Otherwater bodies that do not appear on the MNDNR list as “P” designated but that have priority forother reasons may also be classified by the City as a lake, for example Valley Lake.Table 6.1.6.2 lists the City-designated lakes in Lakeville. The table also shows the City’s lakeclassification for each water body, which is based on the MPCA’s impaired waters listing criteriaand whether the lake is deep/shallow and lies within the North Central Hardwood Forest(NCHF) ecoregion (see Section 4.1.2). None of Lakeville’s lakes fall within the Western Corn BeltPlains ecoregion portion of the city. Descriptions of city lakes can be found in Section 3.10.Lakeville Water Resources Management Plan Page 6-8

Table 6.1.6.1. The City of Lakeville lake classification system.If the lake is located in thefollowing ecoregion:NCHFAnd, it meets the MPCA’sdefinition for:DeepShallowThen, it is given thefollowing Cityclassification:NCHF DeepNCHF ShallowThe BDWMO set lake water quality “action levels” in its Watershed Management Plan that arespecific to Category I and II lakes, and that consider water quality trends (based on analysis ofaverage summer Secchi disc data). The cities within the BDWMO must set similar action levels intheir local watershed management plans. See Section 5.2 of the BDWMO Watershed ManagementPlan (2002) for details on setting action levels within the BDWMO.Outside the BDWMO the City selected goals based on the MPCA impaired waters listing criteria. Thefollowing water quality criteria apply to the City’s lake classifications, and are based on the MPCA’simpaired waters listing criteria or proposed listing criteria (see also Section 4.1.2).Table 6.1.6.2. Lake Classification and Goals for the City of LakevilleDNR #LakeWatershedSurfaceArea (ac)City LakeClassSecchi DiscGoal* (m)Secchi DiscActionLevel** (m)19-2601PMarionEast BayVRWJPO 340 NCHF Deep >1.4 N/A19-2602PMarionMiddle BayVRWJPO 200 NCHF Deep >1.4 N/A19-27P Crystal BDWMO 290 NCHF Deep >2.1*** >1.619-31P Orchard BDWMO 243 NCHF Deep >1.6 >1.619-30P Kingsley BDWMO 35 NCHF Shallow >1.0 >1.019-26P Lee BDWMO 22 NCHF Shallow >1.0 >1.019-43W Valley VRWJPO 8 NCHF Shallow >1.0 N/A*Goals are based on either the MPCA criteria or the BDWMO policies which ever are more stringent.**Action levels are required for lakes within the BDWMO.*** Based on the results from the Crystal and Keller Lake Use Attainability Analysis Diagnostic FeasibilityStudy, (BDWMO, 2003)Lakeville Water Resources Management Plan Page 6-9

6.1.7 Watershed Identified Issues6.1.7.1 Vermillion River Watershed Joint Powers Organization IssuesThe primary issues identified in the Vermillion River Watershed Joint Powers Organization’sWatershed Plan include:1. Vermillion River flow volumes have increased.2. Surface water quality is threatened or impaired.3. The Vermillion River channel and corridor is impacted and sensitive to change.4. Sensitive resources are present and/or threatened or impaired.5. Groundwater quality is threatened or impaired.6. Additional development is expected.7. Data for making informed decisions is limited.8. Public awareness about water resources in the watershed and appropriatestewardship is limited.The VRWJPO Plan, Section 3 provides a detailed discussion of these issues (Vermillion RiverWatershed Joint Powers Organization, Watershed Management Plan, November 3, 2005).This plan’s implementation attempts to deal with these issues as they apply in Lakeville byexplicitly incorporating the VRWJPO Policies.Cities and townships within the VRWJPO who do not adopt the VRWJPO Standards will losepermitting authority for water related development and projects. The City of Lakevilleexpects to retain jurisdiction and permitting authority over development in Lakeville via thisplan’s policies and its implementation tasks. Lakeville Policies presented in this plan areintended to be consistent with the VRWJPO Policies presented in the 2005 Vermillion RiverWatershed Joint Powers Organization Watershed Management Plan as they relate to the Cityof Lakeville.As part of the implementation of this plan, the City will undertake the revision of Cityordinances such that they are consistent with the Vermillion River Watershed Joint PowersOrganization Watershed Standards adopted October 2006.The VRWJPO is also expected to develop inter-community flood control discharge limits atcity boundaries. As part of the implementation of this plan the City will undertake a citywidehydrologic model to demonstrate how the City will attempt to meet these limits.Lakeville Water Resources Management Plan Page 6-10

6.1.7.2 Black Dog Watershed Management Organization IssuesIn an effort to reduce non-point source pollution to water bodies within and downstream ofthe BDWMO, the BDWMO has identified issues and problems in order to set forth goals andpolicies with respect to:erosion controlrunoff quantity and qualitywetland managementpublic educationevaluation and accountabilityFor most water bodies, non-point source runoff is a major contributor of phosphorus. Thegoals of the BDWMO are to improve the quality of stormwater runoff by reducing non-pointsource pollution carried by runoff, and to protect against flooding by increasing availablestormwater storage and promoting infiltration.The BDWMO recognizes that there is a role for the organization as a facilitator inintercommunity flood control issues – issues where the tributary watershed spans more thanone city or outflows cross city/county/WMO boundaries. As facilitator, the BDWMO willassist in fairly allocating costs among the member cities for intercommunity flood controlprojects. The BDWMO will allocate the costs based strictly on hydrology.The BDWMO set special policies for certain subwatersheds. For the subwatersheds thatdrain to either the Credit River or the Lower Minnesota River Watershed District, theBDWMO requires that the rate of runoff leaving the BDWMO be maintained at or beloweither the predevelopment rate (for undeveloped subwatersheds) or the existing rate (forfully developed subwatersheds). For subwatersheds that drain to the Black Dog fen wetlandcomplex and the trout streams, the BDWMO requires that cities maintain or reduce the sizeof the tributary watersheds.One of the BDWMO’s general goals is to keep regulation at the local level, which means theBDWMO will not administer a permit program. The member cities have the responsibility ofmanaging stormwater runoff consistent with the goals and policies of the BDWMO. Detailscan be found in the Black Dog Watershed Management Organization, WatershedManagement Plan, completed May 2002.Erosion and Sediment ControlThe BDWMO member cities are to address erosion and sediment control in their local watermanagement plans. The cities are to require erosion control plans for construction sites,address problems, and adopt, administer, and enforce ordinances addressing erosion andsediment control.Lakeville Water Resources Management Plan Page 6-11

Wetland ManagementThe biological communities of wetlands can be very sensitive to stormwater runoff,development, and human activities. Therefore, the goals of the BDWMO regarding wetlandmanagement are to preserve wetlands and achieve no net loss of wetlands. To achieve thesegoals, the BDWMO required the member cities to develop wetland protection ordinances by2005, based on comprehensive wetland management plans and wetland functions and valuesassessments.Education and Public InvolvementThe BDWMO and the member cities will provide the public with information such as waterquality data, lake water level data, landscaping/lakescaping concepts, construction anddevelopment issues, general hydrology and other water resource related topics.Evaluation and AccountabilityThe BDWMO and the member cities will work together to achieve the goals set forth in theBDWMO plan. The goal of the evaluation and accountability process is to assess the progressof the BDWMO and the member cities toward the agreed upon expectations. The BDWMOand the member cities will identify outcome-based goals for the watershed and specificresources, and will meet annually to discuss progress. Trend analyses will be used to trackwater quality trends. Aesthetic and habitat data will also be tracked. Performance analyseswill be used to track the completion of implementation tasks.The BDWMO has identified strategic water resources which are of broad watershedsignificance and are important to a larger population than just the municipalities in whichthey are located. The BDWMO identified six strategic water resources, three of which are inLakeville: Crystal Lake, Orchard Lake, and Kingsley Lake. The BDWMO will classify, setgoals, monitor water quality, and track water quality trends for all strategic water resources,and will implement lake management actions (as needed) for those strategic water resourceswith intercommunity tributary watersheds.The cities are responsible for managing the non-strategic lakes, ponds and wetlands in theBDWMO, including Lee Lake in Lakeville.Crystal LakeIn 2003 the Black Dog Watershed Management Organization completed the Crystal andKeller Lake Use Attainability Analysis Diagnostic Feasibility Study: Water Quality Issues andPotential Restorative Measures. It outlined the following issues and tasks.Based on its existing and desired use, the BDWMO classified Crystal Lake as a Category Iwater body. The specific goal for Crystal Lake is a trophic state index based on Secchi disctransparency (TSI SD )

Summer average Secchi disc depth of at least 1.6 metersTotal phosphorus concentration of less than 45 µg/LChlorophyll-a concentration of less than 20 µg/LThe City of Burnsville has also set its own goal for summer average Secchi disc depth of atleast 2.1 meters for Crystal Lake.Development is ongoing in parts of the Crystal Lake watershed. The majority of thisdevelopment is occurring in the portions of the watershed that lie in Lakeville. The City ofLakeville requires that this development result in less than a 70 percent total imperviousnessto help mitigate both storm water quantity and quality concerns.Although it was previously observed in Crystal Lake, macrophyte (i.e., lakeweed) surveysperformed during June and August 2002 found no Eurasian watermilfoil present (BluewaterScience, 2002). However, another exotic weed, curlyleaf pondweed, has been observed atnuisance levels over roughly 100 acres of the lake up to the 2007. Curlyleaf pondweed isdetrimental to lakes for three reasons:1. It tends to crowd out native aquatic macrophyte species.2. Dense colonies of the weed may interfere with recreational activities on the lake.3. After curlyleaf pondweed dies out in early July, it may sink to the lake bottom anddecay. When dense colonies of the weed decay, oxygen depletion and release ofphosphorus may occur.Implementation of conventional storm water BMPs, either good housekeeping BMPs (e.g.,source control activities such as street sweeping) or stormwater BMPs (e.g., treatmentmechanisms like runoff detention basins) are already mandated by the stormwatermanagement plans of Burnsville, Lakeville, and Apple Valley. These practices will likelypartially offset any increases in annual phosphorus loading to Crystal and Keller Lakes fromfuture development in the watershed. It is important that all BMPs currently required by theWMO and member municipalities continue to be implemented in addition to thoserecommended below. The recommended management option includes:1. Fertilizer P limitation2. Upgrade certain ponds to provide sufficient water quality treatment storage volume tomeet NURP criteria including CL-21 in Lakeville (completed)3. Add ponding meeting NURP criteria as a regional water quality treatment basin (not inLakeville)4. Enhance Redwood Pond to act as an infiltration basin (not in Lakeville)5. Add a regional infiltration basin (not in Lakeville)Lakeville Water Resources Management Plan Page 6-13

6. Operation of the FeCl3 treatment system withdrawing near surface water (not inLakeville)7. Manage aquatic macrophytes, primarily curlyleaf pondweed by mechanical harvestingSee the Crystal and Keller Lake Use Attainability Analysis Diagnostic Feasibility Study:Water Quality Issues and Potential Restorative Measures, July 2003 for details.Orchard LakeIn conjunction with the city of Lakeville’s diagnostic-feasibility study, zooplankton and algaesamples were collected during 1995 and 1996 in Orchard Lake. Blue-green algae decreasedin dominance from 1995 to 1996, indicating potential improvement in the lake ecosystem.Aquatic plants were identified and enumerated in 1995, as part of the diagnostic study, andin 1999, as part of a later study. The aquatic plant community was dominated by non-nativecurlyleaf pondweed in both 1995 and 1999, but Eurasian water milfoil was not present ineither year.Summer water quality data indicate that Orchard Lake is a eutrophic system. A trendanalysis was performed for each of the water quality parameters (Secchi disc depth, totalphosphorus, and chlorophyll-a). The analysis found no significant trends for totalphosphorus and chlorophyll-a concentrations over time, although the data appear to show ageneral decline. However, there is a significant degrading trend in Secchi disc transparenciesover the same time period, at a rate of about 0.05 meter per year (1 meter over 20 years).The BDWMO set the action level for Orchard Lake Secchi disk readings at 1.6 meters, basedon its classification and use as a Category I lake. Continued monitoring will allow theBDWMO to track the success of implemented best management practices at maintaining thewater quality of Orchard Lake. Additional water quality goals for Orchard Lake are listedbelow:Summer average Secchi disc depth of at least 1.4 metersTotal phosphorus concentration of less than 45 µg/LChlorophyll-a concentration of less than 20 µg/L Carlson TSI index no greater than 55In 2006 the BDWMO developed the Habitat Monitoring of Strategic Water Resources Reportwhich reached the following conclusion regarding Orchard Lake. Orchard Lake is ratedmoderate for overall submergent vegetative quality, based chiefly on an average exoticspecies density (1.7) and an average number of native species (13). During the May 26, 2006an aquatic plant survey was conducted and curlyleaf pondweed was found within all 30sampling stations and was the most dominant plant.Lakeville Water Resources Management Plan Page 6-14

Orchard Lake has an excellent overall emergent vegetation zone quality rating, based on thehigh number of native plants (18) and moderate exotic species coverage (26 to 50 percent).In addition, the water body has an average total percent emergent vegetative cover (26-50%).Hybrid cattail is the dominant exotic species within the emergent zone, although purpleloosestrife is also present and should be of special concern.The overall upland buffer quality is rated moderate for Orchard Lake. The upland bufferaround the lake averages less than 10 feet in width and surrounds less than half of the lake.A total of five exotic plant species were observed in the upland buffer area in 2006 making upgreater than 40 percent of the vegetative cover. The upland buffer is dominated by mowedturf grass which contribute to the degraded value for wildlife. No significant erosion orsedimentation problems were noted for this lake.In 2006 and 2003, based on the MNRAM methodology, Orchard Lake rated moderate foroverall vegetative diversity and wildlife habitat. This compares favorably to the BDWMOhabitat vegetation assessment parameters. The Orchard Lake shoreline wetland communityrated medium for shoreline protection, primarily due to the narrow width of emergent zonevegetation and the minimal vegetative coverage in that zone. Fishery habitat andaesthetics/recreation/education rated high in the 2006 and 2003 MNRAM assessments.The 2006 and 2003 MNRAM assessments also indicate that many of the integral hydrologicand land use processes that affect the lake are intact and in relatively good condition.The habitat assessment results suggest several recommended management activities thatcould help improve the overall wildlife benefits of the lake. Those managementrecommendations are presented below in order of highest to lowest priority:1. Continued control of curlyleaf pondweed, which could increase functions and valuesfor water quality, wildlife habitat, vegetation diversity, aesthetics, and recreation2. Conduct a detailed evaluation of the extent of purple loosestrife and continue tomonitor purple loosestrife-controlling beetle populations3. Increase the connectivity and width of a native upland buffer around the lake toimprove wildlife habitat and water quality benefits. Continue attempts to makelakeshore property owners aware of the lakeshore practices that can harm and thepractices that can improve various lake functions and valuesThe BDWMO set a policy for subwatersheds tributary to the Credit River that restrictsdischarges leaving the BDWMO to either pre-development rates (for undevelopedwatersheds) or existing rates (for fully developed watersheds). The Orchard Lake outlet willcontinue to restrict peak outflow to no more than 65 c.f.s. for the 100 year, 24 hour runoffevent, per BDWMO requirement.Lakeville Water Resources Management Plan Page 6-15

Kingsley LakeThe water quality monitoring data shows that Kingsley Lake is of excellent water quality anda mesotrophic system. The current water quality of Kingsley Lake places the lake within theCategory I classification, although the general public does not currently use the lake for directcontact recreation. The BDWMO classified Kingsley Lake as a Category II water body, basedon its existing and projected future use. The action level for Kingsley Lake, based on aCategory II classification, is a Secchi disc reading of 1.0 meters. Continued monitoring willallow the BDWMO to track the water quality trends in Kingsley Lake. Additional waterquality goals for Kingsley Lake are listed below:Summer average Secchi disc depth of at least 0.9 but less than 1.4 metersTotal phosphorus concentration of at least 45 µg /L but less than 75 µg/LChlorophyll-a concentration of at least 20 µg/L but less than 40 µg/L Carlson TSI index no greater than 60The 2006 Habitat Monitoring of Strategic Water Resources report findings andrecommendations for Kingsley Lake are summarized below.For 2006 Kingsley Lake was rated excellent for overall submergent vegetative quality, whichis an increase compared to the moderate rating of past assessment years, chiefly due to anideal native vegetative density (1.8). However, an average number of native species (13), andan average exotic species density (1.0), also contributed to the high rating. In 2006, a moredetailed submergent vegetation survey was conducted to better assess the extent of curlyleafpondweed. The more detailed survey resulted in the documentation of additional nativespecies, which contributed greatly to the excellent overall submergent vegetative quality.In 2006, as in 2005 and 2003, curlyleaf pondweed was found in Kingsley Lake. In 2005 and2003 only one plant was documented. In 2006 numerous plants were found in thesouthwest portion of Kingsley Lake.Kingsley Lake has an excellent overall emergent vegetation zone quality rating, due to anabove-average number of native species (15) and ideal vegetative cover (51 – 75 percent). Aslittle as 0 to 25 percent of the emergent zone was found to be dominated by exotic species.Although not noted in 2004 - 2006, the exotic species, purple loosestrife, was documented ina few small, isolated locations during the 2003 BDWMO habitat assessment and may still bepresent.The overall upland buffer quality is rated excellent for Kingsley Lake. The upland bufferaround the lake averages 25 to 50 feet in width and surrounds 76 to 100 percent of the lake.A total of 19 native species were observed making up 55-80 percent cover and only 3 exoticplant species were observed in the upland buffer area making up 15-40 percent of thevegetative cover. Common buckthorn (Rhamnus cathartica) dominates the shrub layer inLakeville Water Resources Management Plan Page 6-16

portions of the wooded upland buffer areas around the lake. No significant erosion orsedimentation problems were noted for the lake.The overall vegetative diversity, as in 2003, rated high. The 2006 and 2003 MNRAMassessments also rated Kingsley Lake high for fishery habitat, aesthetics/recreation/education, downstream water quality, hydrologic regime, and flood storage. This indicatesthat many of the integral hydrologic and land use processes that affect the wetland are intactand in relatively good condition.6.1.8 Vermillion River Tributary Trout StreamA branch of the Vermillion River locally known as South Creek runs through a large part ofsouthern and southeastern Lakeville. In 1988 the Commissioner of the Minnesota Departmentof Natural Resources designated an area of the main branch of South Creek as trout streamwithin the City of Lakeville. In 1996 additional tributaries of the creek were added to thedesignation as a result of litigation.The South Creek watershed within Lakeville covers approximately 5050 acres (3.9 square miles).The Airlake Industrial Park covers approximately 1300 acres within the watershed of SouthCreek. The watershed also includes approximately 2400 acres of residential development whileanother 1350 acres are currently rural.Temperature and turbidity are two of the important issues that will govern the viability of thetrout habitat. The Airlake Industrial Park occupying the watershed immediately adjacent to thetrout designated stream is generally seen as a crucial aspect of the surface water and groundwater management for protecting the trout habitat.In 1998 a joint subcommittee of the Lakeville Environmental Affairs Committee and theLakeville Economic Development Commission was created to study the implications of thedesignation and develop a plan to manage the trout stream resource. Upon consultation withstate agencies and Airlake Industrial Park property owners, the Subcommittee resolved to take aproactive approach to management of the resource.As a result, in July 2000 the Lakeville City Council adopted the South Creek Management Plan.Details of the Plan are presented in Section 5.3.1. The plan and implementing ordinances requirethe following protective measures:Infiltration depressions for all new development within the South Creek StormwaterDistrict with volume sufficient to contain 1.5” of rainfall over the impervious surface areafor all current and future phases of the developmentSite landscaping with shade trees requirements for the trout stream channel, tributaryflows and/or infiltration areasLakeville Water Resources Management Plan Page 6-17

Transfer of ownership to the city of a minimum 50 foot buffer on either side of the streamcenterline in newly platted areas and where practical in existing areasThe City has also identified programmatic improvement and maintenance of infiltration swaleswithin the South Creek watershed in its implementation plan.These controls and the combined impact of the other city-wide development controls effectivelyprotect the trout stream.6.2STORMWATER RUNOFF RATES AND VOLUMESPROBLEMS AND ISSUES6.2.1 General IssuesIn a natural, undeveloped setting, the ground is often pervious, which means that water(including stormwater runoff) can infiltrate into the soil. Land development dramaticallychanges how stormwater runoff moves in the local watershed. The changes begin duringconstruction, when clearing and grading of the site results in less infiltration, higher rates andvolumes of stormwater runoff, and increased erosion. As construction continues, groundsurfaces become covered with impervious materials (e.g., asphalt and concrete) that preventinfiltration of water into the soil. As a result, the rate and volume of stormwater runoff from thesite further increases, which can create significant problems for downstream water resources.Further, the reduced amount of infiltration means less wateris being recharged into the groundwater system, which canresult in decreased base flows in creeks and streams and,potentially, a loss to the long-term sustainability ofgroundwater drinking supplies.If the land drains to a landlocked basin, the additionalvolume of runoff can increase the water level and flood levelof the basin. If the land drains to a stream, the additionalrunoff volume can cause the stream to flow full for longerdurations, which increases the erosion potential. Theincrease in runoff rates from sites can also increase floodingrisks and erosion.Damages caused byflooding include:Damage to homes,businesses and otherbuildingsAlthough both high water levels (flooding) and low waterlevels are of concern to city residents and City staff, moreconcern and attention is usually paid to flooding because it is a greater threat to public healthand safety, and can result in significant economic losses.Damage to infrastructure(e.g., roads, bridges)Flooding of individualseptic systems, renderingthem unusableDamage or destruction ofrecreational trails andbridgesLakeville Water Resources Management Plan Page 6-18

Flooding may cause other damages that are harder to quantify, including the following:Flooding of roads so they are impassable to emergency vehicles, residents, and schoolbusesShoreline erosionDestruction of vegetation, such as grass, shrubs, trees, etc.Unavailability of recreational facilities for use by the public (e.g., inundation of shoreline)and/or restricted recreational use of water bodiesMore strain on budgets and personnel for repairing flood-damaged facilities andcontrolling public use of facilities during flooding eventsAlterations to mix and diversity of wildlife species as a result of inundation of uplandhabitatsOf special concern is flooding on landlocked water bodies, which prolongs the damages andimpacts. Since there is no surface outlet, runoff which collects in these depressions is removedonly by seepage and evaporation. As water tables rise during periods of above-averageprecipitation, seepage out of landlocked basins can also decrease. As a result, landlocked basinsare subject to wide variations in water levels and their 100-year floodplains typically cover largeareas.Landlocked basins can also provide benefits. The long lasting seepage from landlocked basinsprovides important groundwater recharge benefits. Also, landlocked basins do not dischargesurface waters to downstream basins, which could otherwise be negatively impacted by theadditional stormwater volume.The City may be requested to provide outlets from landlocked basins to prevent damages thatoccur during periods of sustained high water levels, but it is not always feasible or reasonable forthe City to do so. For example, it may not be feasible to provide outlets because of the longdistances to the nearest outlet, the depth of the pipe, and the capacity of the nearest outlet. Itmay not be reasonable to provide outlets because of the downstream impacts on flood levelsand/or water quality. It can also be difficult for the City to provide even temporary relief duringflooding situations for the same reasons that it is difficult to provide permanent outlets.Floodplain management is the management of development and other activities in or near thefloodplain to prevent flood damages. The MDNR defines floodplain management as “the fullrange of public policy and action for ensuring wise use of the floodplains. It includes everythingfrom collection and dissemination of flood control information to actual acquisition of floodplainlands, construction of flood control measures, and enactment and administration of codes,ordinances, and statutes regarding floodplain land use.”Lakeville Water Resources Management Plan Page 6-19

Minnesota law defines the floodplain as the land adjoining lakes, water basins, rivers, andwatercourses that has been or may be covered by the “100-year” or “regional” flood. Floodplainsof larger basins and streams are mapped by the FEMA on Flood Insurance Rate Maps, which areincluded in community Flood Insurance Studies. The City manages activities in the FEMAdesignatedfloodplain areas through the Lakeville floodplain ordinance.The City has determined 100-year flood levels for many water bodies that are not mapped onFEMA Flood Insurance Rate Maps. The City manages activities within the floodplains of thesewater bodies through its permit/approval processes. An important requirement in the City’sfloodplain ordinance and City policies is the setting of the lowest floor elevations. The City’sestablishment of flood levels and lowest floor elevation requirements have been very effective atpreventing the construction of homes, businesses and other structures within the floodplain.Although less likely to result in significant economic losses, the City recognizes low water levelscan also have negative impacts. Possible negative impacts include interference with ordiminished recreational use of the water resources through reduced or lost access to the waterresource by the public and shoreline residents, reduced aesthetic enjoyment of the waterresources (e.g., from mud flats, smells), loss of wildlife habitat, and winterkill of fish. The Citycannot control drought, which is the main cause of deleterious low water levels.6.2.2 Floodplain FIRM ModificationsThe City has found that making adjustments to the official FEMA flood elevation FIRM maps isextremely time consuming and costly. These changes are often necessary due to the rapiddevelopment that occurs in Lakeville. The City will encourage efforts to simplify this processtoward optimizing the use of time and public funds.6.3 EROSION AND SEDIMENT CONTROL PROBLEMS AND ISSUESSediment is as a major contributor to water pollution. Stormwater runoff from streets, parking lots,and other impervious surfaces carries suspended sediment consisting of fine particles of soil, dustand dirt carried in moving water. Abundant amounts of suspended sediment are carried bystormwater runoff when erosion occurs.Although erosion and sedimentation are natural processes, they are often accelerated by humanactivities, especially construction. Prior to construction, the existing vegetation on the site interceptsrainfall and slows down stormwater runoff rates, which allows more time for runoff to infiltrate intothe soil. When a construction site is cleared and graded, the vegetation (and its beneficial effects) isremoved. Also, natural depressions that provided temporary storage of rainfall are filled and graded,and soils are exposed and compacted, resulting in increased erosion, sedimentation and decreasedinfiltration. As a result, the rate and volume of stormwater runoff from the site increases (MinnesotaUrban Small Sites BMP Manual, 2001). The increased stormwater runoff rates and volumes causeLakeville Water Resources Management Plan Page 6-20

increased soil erosion, which releases significant amounts of sediment that may enter the City’swater resources.Regardless of its source, sediment deposition decreases water depth, degrades water quality,smothers fish and wildlife habitat, and degrades aesthetics. Sediment deposition can also wholly orpartially block culverts, manholes, storm sewers, etc., causing flooding. Sediment deposition indetention ponds and wetlands also reduces the storage volume capacity, resulting in higher floodlevels and/or reducing the amount of water quality treatment provided. Suspended sediment,carried in water, clouds lakes and streams and disturbs aquatic habitats. Sediment also reduces theoxygen content of water and is a major source of phosphorus, which is frequently bound to the fineparticles. Erosion also results in channelization of stormwater flow, increasing the rate ofstormwater runoff, and further accelerating erosion.As erosion and sedimentation increase, the City’s stormwater management systems (e.g., ponds,pipes) require more frequent maintenance, repair, and/or modification to ensure they will functionas designed. Monitoring the stormwater system, including inspection of sediment build-up instormwater ponds, will be an increasingly important task for the City. Continued urbanization in thecity will result in increased erosion and sedimentation, unless effective erosion prevention andsediment control measures are implemented before, during, and after construction.In recognition of these issues, the City’s ordinances and approval processes address erosion andsediment control at construction sites. The current ordinance requires implementation of temporaryand permanent erosion and sediment control measures for developments and other projects.In addition to meeting City requirements, owners and operators of construction sites disturbing oneor more acres of land must obtain a National Pollutant Discharge Elimination System (NPDES)Construction Stormwater Permit from the Minnesota Pollution Control Agency (MPCA).Owners/operators of sites smaller than one acre that are a part of a larger common plan ofdevelopment or sale that is one acre or more must also obtain permit coverage.The MPCA developed the NPDES General Storm-water Permit for Construction Activity (NPDESconstruction permit), which went into effect on August 1, 2003. A key permit requirement is thedevelopment and implementation of a Stormwater Pollution Prevention Plan (SWPPP) withappropriate best management practices (BMPs). The SWPPP must be a combination of narrativeand plan sheets that address foreseeable conditions, include a description of the constructionactivity, and address the potential for discharge of sediment and/or other potential pollutants fromthe site. The SWPPP must include the following elements:Temporary erosion prevention and sediment control BMPsPermanent erosion prevention and sediment control BMPsPermanent storm water management systemPollution prevention management measuresLakeville Water Resources Management Plan Page 6-21

The project’s plans and specifications must incorporate the SWPPP before applying for NPDESpermit coverage. The permittee must also ensure final stabilization of the site, which includes finalstabilization of individual building lots.6.3.1 Lake Marion ChannelOn the south west corner of Lake Marion, a channel exists that allows water to flow from pondingareas on newly developed land. This channel has experienced a high degree of erosion due to theincreased flow within it. The erosion is likely impacting water quality in Lake Marion andleading to degradation of the channel profile. The City is planning to stabilize this channel aspart of its implementation program for this plan.6.4 ADEQUACY OF EXISTING PROGRAMS6.4.1 City Ordinances and Official ControlsThe City of Lakeville actively and progressively manages stormwater to protect life, property,waterbodies within the city, and receiving waters outside the city. Toward this end, the City ofLakeville creates and implements regulatory programs that accomplish these aims. The Cityintends to continue implementing the following regulations and programs.City regulations and land use controls include the following water resource-relatedplans and ordinances: The Lakeville Wetland Management Plan (2003) The South Creek Management Plan (2000) The Lakeville Stormwater Pollution Prevention Program (2007) Floodplain zoning requirements (Lakeville City Code, Chapter 101) Shoreland zoning ordinance (Lakeville City Zoning Code, Chapter 102) Zoning ordinance (Lakeville City Code, Title 11) Subdivision ordinance (Lakeville City Code, Title 10) Surface Water Management Utility (Lakeville City Code, Chapter 13) Wetland protection (Lakeville City Code, Section 10-4-8) Storm drainage (Lakeville City Code, Section 10-4-6) Grading, drainage, and erosion control (Lakeville City Code, Section 10-4-5) Protected areas (Lakeville City Code, Section 10-4-7) Tree preservation ordinance (Lakeville City Code, Section 10-4-11)Lakeville Water Resources Management Plan Page 6-22

The City requires permits and/or approvals for land disturbing projects (includingdevelopments), depending on the type of project. The following is a listing of the water resourceor stormwater related City permits and/or approvals:Concept plan reviewPreliminary plat approvalFinal plat approvalRezoning approvalComprehensive Plan amendmentPlanned unit development (PUD) PermitConditional use permitBuilding permitLand alteration (excavation and fill) permitWetland Conservation Act approvalApplications for preliminary plat approvals, major site plan approval, and planned unitdevelopment permits must include a grading and drainage plan, an erosion control plan, a treepreservation plan and a wetland plan.The City of Lakeville acts as the Local Governmental Unit for the Wetland Conservation Act.This includes requiring and verifying that all projects impacting wetlands meet the requirementsof the Minnesota Wetland Conservation Act and the Lakeville Wetland Management Plan.The City of Lakeville is required to meet the conditions of its NPDES MS4 permit and toimplement the Lakeville Storm Water Pollution Prevention Program. The City continues toactively engage the MPCA and others to keep its permit and implementation up to date withregard to technology and regulations.The City also actively works with the BDWMO and the VRWJPO toward accomplishing commongoals and adhering to the policies of these watershed organizations.In order to improve the City’s efficacy regarding surface water management, the City will reviewand update its existing plans and ordinances to bring them in conformance with the policies andgoals of this Plan, the BDWMO and VRWJPO Plans, and the NPDES MS4 Permit requirements.6.4.2 Education and Public Involvement ProgramThe City of Lakeville maintains various education and communication programs aimed at waterresources issues. The City develops and distributes articles and information regarding the City’sStorm Water Pollution Prevention Plan including information on:Lakeville Water Resources Management Plan Page 6-23

stormwater issuesnon-point source pollutionNPDES regulation and guidanceannual public meetingsillicit dischargeserosion controlshoreline managementlocal agency contactsstormwater website linkscomposting and pollution preventionThis information is distributed through City mailings, workshops, presentations, websitepostings, and articles in the City newsletter.The City also works collaboratively with the Dakota County Soil & Water Conservation District(Dakota SWCD), the Black Dog Watershed Management Organization (BDWMO), and theVermillion River Watershed Joint Powers Board (VRWJPB) in distributing educational materialsand promoting/supporting outreach programs. Programs consist of K-12 Outdoor EducationalField Day (Dakota SWCD), Minnesota Envirothon (Dakota SWCD), presentations to the DakotaCounty 4-H Club (Dakota SWCD), volunteer stream monitoring (VRWJPB), Citizen AssistedLake Monitoring, Wetland Health Evaluation Program, City Newsletters (minimum of two peryear), and general conservation information and presentations (Dakota SWCD, BDWMO,VRWJPB).The City’s website provides pages and links devoted to water resource related issues. Topics mayinclude, the Comprehensive Stormwater Management Plan, the Nondegradation Plan, SWPPPinformation, best management practices, illicit discharge prevention and detection information,information on non-point source pollution, and local contact information for residents to requestfurther information on specific stormwater topics or to report a stormwater related infraction.The City’s website is located at http://www.ci.lakeville.mn.us/ .The City hosts an annual public meeting to distribute educational materials and present anoverview of the MS4 program and the City’s SWPPP. Oral and written statements are receivedand considered for inclusion in the SWPPP by City staff.The City will increase the public’s awareness of the potential sources and negative effects of illicitnon-stormwater discharges, as well as alternative uses for unwanted materials by providinginformation on recycling options, services, and programs within the City, such as drop-off sitesLakeville Water Resources Management Plan Page 6-24

for household hazardous waste. The City will also review the current educational activitiesundertaken by its staff to identify, prevent and correct illicit discharges from daily public worksactivities and other general City operations. These activities may include, but are not limited to,educational brochures, newsletters, videos, and workshops.At this time, this recently updated communication program is deemed to meet the needs of thecommunity. In the future, the City will periodically review its educational programs to keep thiscommunication up to date and useful.6.4.3 Groundwater ProtectionOne way the City protects its groundwater supply is by following current standards for wellconstruction. All of the city’s groundwater wells meet current standards, which mean the wellsdo not present pathways for contamination to readily enter the groundwater supply.In some areas, the city’s aquifer has a high sensitivity to contamination due to the local geologicalsetting and provides a relatively low level of protection. Source water susceptibility refers to thelikelihood that a contaminant will reach the source of drinking water. It reflects the assessmentof well sensitivity, aquifer sensitivity, and water quality data. The susceptibility of the city’ssource water is considered high due to high tritium content in water within the bedrock aquiferand the natural geologic conditions.Since the city’s groundwater supply has a high sensitivity and a high susceptibility tocontamination, it is important that recharge areas be protected from contamination. In an effortto reduce the potential adverse affects of pollutants from surface infiltration, the City of Lakevillewill consider the Minnesota Department of Health’s Evaluating Proposed StormwaterInfiltration Projects in Vulnerable Wellhead Protection Areas, as amended, as guidance inevaluating all proposed infiltration projects within or adjacent to vulnerable portions of theDrinking Water Supply Management Areas (DWSMA). The City will also utilize additionalpertinent information (when available) in determining the potential adverse effects ofstormwater infiltration to the vulnerable DWSMA.If the proposed infiltration/discharge is determined by the City to potentially cause adverseeffects to the local drinking water supply, the City will prohibit the construction of the infiltrationarea or incorporate the necessary BMPs to reduce the identified pollutant(s) prior to infiltratinginto the vulnerable portions of the DWSMA. The DWSMAs are shown in Figure 6.4.3.6.4.4 Maintenance of Stormwater SystemThe City of Lakeville is responsible for maintaining its stormwater system including storm sewerpipes, ponds, pond inlets and outlets, and channels.For ponds, the amount of sediment which settles out onto the bottom must be monitored todetermine when sediment removal is needed. Sediments settle onto a layer on the bottom of thepond and displace water storage volume of the pond. The depth of accumulated sediment can beLakeville Water Resources Management Plan Page 6-25

measured by establishing a benchmark system. Elevations for the normal water level in theponds can be recorded and periodically checked against the depth to determine when amaximum allowable amount of the pond’s storage is filled by sediment. Sediment removal isthen necessary because the removal efficiency of a pond decreases as the storage volumedecreases.The City of Lakeville has an aggressive program of stormwater pond maintenance. The programincludes cleaning of the primary stormwater ponds as needed throughout the city. A stormwaterpond maintenance program has been active since 1998 on an annual basis. The Public WorksDepartment conducts a visual inspection of ponds and determines the level of maintenanceneeded for 20% of city ponds each year on a rotating basis so each pond is inspected every 5years.Along with the stormwater pond sediment removal program, the City of Lakeville activelyremoves sediments from catch basins and other environmental manholes. The City of Lakevillealso has an active street sweeping program. The City currently brush or vacuum sweeps Cityowned streets a minimum of twice per year in an effort to reduce the amount of sediment andtrash from reaching the storm sewer system and surface waters. One street sweeping activity willoccur in the spring (April-June), and the second activity will occur in the fall (September –November). Sweepings are taken to a dedicated soil storage area.The City of Lakeville’s MS4 Permit SWPPP identified maintenance issues and outlinedimplementation tasks to address those issues. The identified tasks include:Lakeville Water Resources Management Plan Page 6-26

Review the practices and policies for road salt applicationAnnually review and adjust practice in the use of fertilizer, pesticide and herbicideapplication, mowing and discharge operations, grass clipping collection, mulching andcompostingDetermine whether system repair, replacement, or maintenance measures are necessaryfrom evaluating inspection reports and other pertinent informationProvide training materials and workshops to City staff to help reduce stormwaterpollution caused from park maintenance, fleet and building maintenance, newconstruction and land disturbances, outfall inspections, and storm sewer systemmaintenanceInspect all mapped outfalls, sediment basins, infiltration basins, filtration basins andponds within the City’s storm sewer system and record resultsInspect post-construction BMPs then evaluate inspection records for determining thecorrective maintenance actions (if necessary) for the long-term operation of allstormwater management facilities owned by the City of LakevilleDocument inspections, repairs, and maintenance projects of its structural pollutioncontrol devicesKeeping the storm sewer map currentAnnually locate and inspect all exposed stockpiles and storage/material handling areaslocated on City owned properties. All existing onsite BMPs will be inspected forconformance to NPDES Phase II permit requirements. Any identified erosion controlissues will be corrected and documented per NPDES Phase II standardsRetainage of records of inspection results and any maintenance performed orrecommended. After 2 years of inspections, if patterns of maintenance become apparent,the frequency of inspections may be adjusted6.4.5 Adequacy of Existing Capital Improvement and Implementation Programs toCorrect ProblemsThis plan, along with its capital improvement and implementation programs, combined with theexisting Surface Water Utility Fund gives the City adequate tools to correct current and futureproblems.The City will continue to use the Surface Water Utility Fee program set up in 1994 to fundstormwater related activities. The City's Storm Water Utility revenue is generated by feesaccording to impervious surface coverage. The Storm Water Utility Fee is the primary fundingsource for all storm water improvements related to the City's Water Resources Management Planand NPDES Phase II requirements. This program is periodically reviewed to determine itsadequacy for funding the projects and programs needed.Lakeville Water Resources Management Plan Page 6-27

Table 6.4 Summary of Stormwater Issues for the City of LakevilleCategoryNPDES StormwaterPollution PreventionPlan (SWPPP)Public education & outreachPublic participationIssueIllicit discharge detection and eliminationConstruction site runoff controlPost construction stormwater managementPollution prevention/housekeepingDetermination of no prudent/feasible alternatives to discharge torestricted watersEvaluation of infiltration within source water protection areasNondegradation PlanInfiltration standardUpdate ordinances to conform with VRWJPO StandardsStream corridor buffersEducation on buffers and illicit dischargeSpill prevention, inspection and response planProhibit infiltration in 1 year travel zone at WHPTracking BMP implementationImpaired WatersLee LakeCrystal LakeNorth CreekSouth CreekTMDL developmentMet CouncilReduction of stormwater volumeIncrease stormwater qualityMaximize infiltrationThermal pollutionWetland managementNondegradation goalsWater quality goalsLakeville Water Resources Management Plan Page 6-28

BDWMOCategoryIssueCrystal Lake flooding and water quality goalsKingsley Lake water quality goalsOrchard Lake outflow rate and water quality goalsStormwater runoff water qualityIntercommunity flood controlWetland protectionWater resources educationMember accountability and evaluationVRWJPORiver flow volumes have increasedSurface water quality is threatened or impairedVermillion River corridor is threatened or impairedSensitive resources are present and/or threatened or impairedGroundwater quality is threatened or impairedAdditional development is expectedData for informed decisions is limitedPublic awareness about water resources in the watershed andappropriate stewardship is limitedInter-community flood controlFuture discharge limits at City boundariesVRWJPO Policies and StandardsCity IssuesRetain permitting authority within the VRWJPO areaReview/revise ordinances for consistency with VRWJPO andBDWMO StandardsFuture city-wide hydraulic modelingFloodplain modificationsErosion at ravine west of Lake MarionTracking BMP implementationStormwater system maintenanceLakeville Water Resources Management Plan Page 6-29

6.5 OPPORTUNITIESThe City of Lakeville has several distinct opportunities which might assist in implementing this plan.The City will actively pursue these opportunities.PartnershipsThe Black Dog Watershed Management Organization, the Vermillion River Joint PowersOrganization, and the Dakota County Soil and Water Conservation District provide technical supportand funding toward solving various water resource problems and completing water resourceprojects. These organizations have a long record of working successfully with the individual citiestoward meeting shared goals. The City will continue to collaborate and contribute to thisorganization and take advantage of the available benefits.Grant ApplicationsThe City will continue its efforts to actively seek opportunities and apply for grants and other fundingas it becomes available. These funds can provide an important resource for funding water resourceprojects.RedevelopmentThe City will continue to be proactive in using the controls at its disposal to insure that opportunitiespresented by re-development to improve the stormwater systems and implement the policies of thisplan are not lost.Agricultural Land ConversionResidential development of agricultural land typically results in reduced loading of sediment toreceiving waters. Lakeville still has large areas of agricultural land that is expected to develop intoresidential neighborhoods. Along with the opportunity to apply stormwater BMPs with thedevelopment, these projects will reduce the acreage of agricultural land acting as a source ofsediment in stormwater runoff.Lakeville Water Resources Management Plan Page 6-30

Crystal Lake160TH ST W162ND ST WValley LakeLee LakeKingsley Lake212650!.207708!.4567 31Barr Footer: Date: 5/14/2008 12:28:22 PM File: I:\Client\Lakeville\2319A29_WR_Management_Plan\Data_Delivery_to_City\Maps\Section6\Figure_6_4_3_Wellhead_Protection_Areas.mxd User: arm2Orchard Lake161436!.4567 23!.!.!.!. !. !.185TH ST W!.§¨¦ 35!.456 70554192Lake Marion1614094332964567 50596650554215651737!.IPAVA AVE554193655907!.5629914567 9South Creek215TH ST W603073DODD BLVDCEDAR AVENorth Branch of South Creek202ND ST W207727East Branch of South Creek!.190TH ST WSouth Branch of South CreekNorth CreekPILOT KNOB RDFigure 6.4.3WELLHEAD PROTECTION AREASCity of LakevilleWater Resources Management PlanMunicipal BoundaryParcel Boundary!. City Wells (with Unique Well Number)StreamsLakesOne Year Travel Time ZoneWell Head Protection AreaData Sources: City of Lakeville, Minnesota DNR, MnDOT.Imagery Source: Aerials Express, 2006.I3,500 1,750 0 3,500Feet750 375 0 750 1,500Meters

Section 7.0 Implementation PlanThis section describes the significant components of the City’s WRMP implementation program,including its NPDES Phase II MS4 permit, operation and maintenance of its stormwater system,education and public involvement, funding, ordinance implementation and official controls, andimplementation priorities. The implementation program is presented at the end of this sectionin a series of tables. Tables 7.1 - 7.6 present summary details of the implementation program,including a project description, cost estimate, potential funding sources, and proposed years ofimplementation. Tables 7.7 – 7.12 summarize the implementation program timeline, listingthe project number and estimated costs for every year from 2008-2017. The tables are arrangedas follows:Details TimelineCapital improvement projects Table 7.1 Table 7.7Studies Table 7.2 Table 7.8Official controls Table 7.3 Table 7.9Public education, outreach, and participation Table 7.4 Table 7.10Lakes management program Table 7.5 Table 7.11Operation and maintenance Table 7.6 Table 7.127.1 NPDES PHASE II MS4 PERMITThe City of Lakeville is included in a group of communities with populations greater than 10,000that are federally required to obtain a Municipal Separate Storm Sewer System (MS4) permit formanaging non-point source storm water. The Phase II NPDES permitting process requires citiessuch as Lakeville to file a Phase II NPDES permit with the Minnesota Pollution Control Agency(MPCA), which addresses how the City will regulate and improve storm water discharges. Thepermit must include a Storm Water Pollution Prevention Program (SWPPP) addressing all of therequirements of the permit.The SWPPP outlines the appropriate best management practices (BMPs) for the City to controlor reduce the pollutants in stormwater runoff to the maximum extent practicable. The City willaccomplish this through the implementation of the BMPs outlined within its SWPPP. TheseBMPs will be a combination of education, maintenance, control techniques, system design andengineering methods, and other such provisions that are appropriate to meet the requirementsof the NDPES Phase II permit. BMPs have been planned and implemented to address each ofthe six minimum control measures as outlined in the rules:Lakeville Water Resources Management Plan Page 7-1

1. Public education and outreach on stormwater impacts2. Public participation/involvement3. Illicit discharge detection and elimination4. Construction site stormwater runoff control5. Post-construction stormwater management in new development and redevelopment6. Pollution prevention/good housekeeping for municipal operationsFor each of these six minimum control measures, the City identified appropriate BMPs, alongwith measurable goals, an implementation schedule, and the persons responsible to completeeach measure. Since the City must also complete a Loading Assessment and a NondegradationReport as part of its MS4 Storm Water Permit, this activity is included as separate BMPs in theCity’s SWPPP.The City’s non-degradation report was developed to address modifications to the SWPPP formeasures that may be necessary to meet the new, applicable requirements of Appendices C andD in the re-issued permit. Appendix C covers discharges to trout waters and wetlands that areapplicable to the city of Lakeville. Appendix D covers the non-degradation requirements forSelected MS4s (30 permittees including the city of Lakeville), including the development of aloading assessment and non-degradation report. The Lakeville Non-degradation Report ispresented in Appendix D.The Lakeville loading assessment and nondegradation report were completed for the City’s MS4NPDES Permit assuming that future BMP implementation would follow the VRWJPO draft rules andstandards (VRWJPO, 2006) for most of the city, with the exception of the South Creek watershed,which would continue to follow the more stringent volume control requirements established in theSouth Creek Management Plan. As a result, the city will update its development review policies,standards and procedures, as cited in the SWPPP. This approach will ensure the following:Receiving water quality should be improved for lakes, wetlands and streams in Lakeville.Channel erosion and stream morphology changes will be controlled.Protection will be provided for the physical and biological integrity of stream and wetlandcorridors.Temperature changes for trout streams and their tributaries will be mitigated and changes inflow will be controlled.Controlled bounce and duration of inundation in the city’s wetlands and preservation of thefunctions and values for each type of wetland classification.Wherever possible, the rules will be applied to redevelopment projects to mitigate pastincreases in storm water runoff volume and further improve receiving water quality andhabitat.Lakeville Water Resources Management Plan Page 7-2

In addition, the SWPPP will be modified to discuss further protection for the physical and biologicalintegrity within the trout stream watersheds by implementing the following measures:Establishment of buffers along stream corridors, based on the most restrictive requirementsfor each type of corridor in the South Creek Management Plan and the VRWJPO rulesContinued education of landowners and residents of existing developments about theimportance of maintaining existing stream buffers and eliminating illicit dischargesEstablishing spill prevention and response procedures for industrial and municipaloperations within the watershedsIn the few projects where the requirements of the Wetland Conservation Act (WCA) are not ascomprehensive as MPCA water quality standards, the requirements of the NPDES permit will requirea Local Governmental Unit to make a determination that will also satisfy Minn. R. 7050.0186. As aresult, Lakeville will reference both the WCA and Minn. R. 7050.0186 requirements for wetlandprotection in the Wetland Management Plan and the SWPPP.The SWPPP will be revised to show where the vulnerable wellhead protection areas are within thecity and define the measures that will reduce the threat to drinking water to the maximum extentpracticable. These measures will be developed in accordance with the Minnesota Department ofHealth’s, Evaluating Proposed Storm Water Infiltration Projects in Vulnerable Wellhead ProtectionAreas, and the MPCA’s, Minnesota Stormwater Manual guidance for potential stormwater hotspots.As future BMPs may be needed or required based on future hydrologic modeling, the cities NPDESpermit, and/or TMDL studies, the city will identify appropriate locations and add them to the city’simplementation program.Prior to June 30 of each year of the five-year permit cycle, the City must hold an annual publicmeeting. At this meeting, the City distributes educational materials and presents an overview of theMS4 program and the City’s SWPPP. The City also receives oral and written statements andconsiders them for inclusion into the SWPPP. Also prior to June 30, the City must submit an annualreport to the MPCA. This annual report summarizes the following:1. Status of Compliance with Permit Conditions The annual report contains anassessment of the appropriateness of the BMPs and the City’s progress toward achievingthe identified measurable goals for each of the minimum control measures. Thisassessment is based on results collected and analyzed, inspection findings, and publicinput received during the reporting period.2. Work Plan The annual report lists the stormwater activities that are planned to beundertaken in the next reporting cycle.3. Modifications to the SWPPP The annual report identifies any changes to BMPs ormeasurable goals for any of the minimum control measures.Lakeville Water Resources Management Plan Page 7-3

4. Notice of Coordinated Activities A notice is included in the annual report for anyportions of the permit for which a government entity or organization outside of the MS4is being utilized to fulfill any BMP contained in the SWPPP.The SWPPP BMP implementation program is incorporated into the City’s overall stormwaterimplementation program presented in Tables 7.1-7.12.7.2 OPERATION AND MAINTENANCE OF STORMWATER SYSTEMSThe City of Lakeville is responsible for maintaining its stormwater system including storm sewerpipes, ponds, pond inlets and outlets, and channels. The City will continue and expand upon itsoperation and maintenance activities to ensure that the city’s system functions as designed. TheCity’s operation and maintenance program is closely tied with the City’s implementation of itsNPDES Phase II MS4 permit (See Section 6.4.4). The City’s operation and maintenanceprogram is incorporated into the implementation program Tables 7.6 and 7.12.7.2.1 Need and frequency for sweepingThe City of Lakeville has an active street sweeping program. The City currently brush orvacuum sweeps city-owned streets a minimum of twice per year in an effort to reduce theamount of sediment and trash from reaching the storm sewer system and surface waters.One street sweeping activity will occur in the spring (April-June), and the second activity willoccur in the fall (September –November). Sweepings are taken to a dedicated soil storagearea. This program is effective and will be continued.7.2.2 Need and frequency for inspecting and maintaining infrastructureThe City of Lakeville has an aggressive program of stormwater pond inspection andmaintenance. The program includes cleaning of the primary stormwater ponds as neededthroughout the city. A stormwater pond maintenance program has been active since 1998 onan annual basis. The Public Works Department conducts a visual inspection of ponds anddetermines the level of maintenance needed for 20% of city ponds each year on a rotatingbasis so each pond is inspected every 5 years.Along with the stormwater pond sediment removal program, the City of Lakeville inspectsand actively removes sediments from catch basins and other environmental manholes. Thisprogram includes rigorous annual inspection and repair of other stormwater managementinfrastructure as detailed in the City’s SWPPP and summarized in Section 6.4.4.7.2.3 Adequacy of maintenance programThe City’s current program based on the Lakeville SWPPP is deemed as adequate to meet theconditions of the City’s NPDES Permit and to maintain an effective stormwater managementsystem.Lakeville Water Resources Management Plan Page 7-4

7.3 EDUCATION AND PUBLIC INVOLVEMENT PROGRAMThe City of Lakeville maintains various education and communication programs aimed at waterresources issues. The City develops and distributes articles and information regarding the City’sStorm Water Pollution Prevention Plan including information on: stormwater issues non-point source pollution NPDES regulation and guidance annual public meetings illicit discharges erosion control shoreline management local agency contacts stormwater website links composting and pollution preventionThis information is distributed through City mailings, workshops, presentations, websitepostings, and articles in the City newsletter.The City also works collaboratively with the Dakota County Soil & Water Conservation District(Dakota SWCD), the Black Dog Watershed Management Organization (BDWMO), and theVermillion River Watershed Joint Powers Organization (VRWJPO) in distributing educationalmaterials and promoting/supporting outreach programs. Programs consist of K-12 OutdoorEducational Field Day (Dakota SWCD), Minnesota Envirothon (Dakota SWCD), presentations to theDakota County 4-H Club (Dakota SWCD), volunteer stream monitoring (VRWJPO), Citizen AssistedLake Monitoring, Wetland Health Evaluation Program, City Newsletters (minimum of two per year),and general conservation information and presentations (Dakota SWCD, BDWMO, VRWJPO).The City’s website provides pages and links devoted to water resource related issues. Topics mayinclude the Water Resources Management Plan, the Nondegradation Plan, SWPPP information,best management practices, illicit discharge prevention and detection information, informationon non-point source pollution, and local contact information for residents to request furtherinformation on specific stormwater topics or to report a stormwater related infraction.The City hosts an annual public meeting to distribute educational materials and present an overviewof the MS4 program and the City’s SWPPP. Oral and written statements are received and consideredfor inclusion in the SWPPP by City staff.The City will increase the public’s awareness of the potential sources and negative effects of illicitnon-stormwater discharges, as well as alternative uses for unwanted materials by providinginformation on recycling options, services, and programs within the City, such as drop-off sites forLakeville Water Resources Management Plan Page 7-5

household hazardous waste. The City will also review the current educational activities undertakenby its staff to identify, prevent and correct illicit discharges from daily public works activities andother general City operations. These activities may include, but are not limited to, educationalbrochures, newsletters, videos, and workshops.At this time, this recently updated communication program is deemed to meet the needs of thecommunity. In the future, the City will periodically review its educational programs to keep thiscommunication up to date and useful.7.4 FUNDING OF IMPLEMENTATION PROGRAMThe City will continue to use the Surface Water Utility Fee program set up in 1994 to fundstormwater related activities. The City's Surface Water Management Utility revenue is generated byfees according to impervious surface coverage. The Surface Water Management Utility Fee is theprimary funding source for all water quality improvements related to the City's Water ResourcesManagement Plan and NPDES Phase II requirements. This program is periodically reviewed todetermine its adequacy for funding the projects and programs needed.Funding is also required for the construction of new trunk storm sewer systems and for capitalimprovement projects on the existing storm sewer system. Funding for construction of trunkstorm sewer systems that serve new developments are obtained by the city from the storm sewerarea charge for all new developments. The construction of new trunk systems are assessed on anarea basis at the time of development. The trunk area charge is based on the estimated volumeof runoff that will occur from the parcel, which is largely determined by the amount ofimpervious area for the proposed land use. This is accomplished using an assessment ratio forvarious land uses. The program is regularly updated based on an index of construction costs toaccount for inflation and other market forces.The City of Lakeville will begin the development of an updated citywide hydrologic model in2008. This model will account for changes that have occurred in the system over the last 13years and will conform to the new VRWJPO model results and resulting restrictions. Theupdated modeling will likely result in some changes in pond locations and volumes as well aschanges for pipe sizing. As a result, the trunk fund financing program will be updated based onthe updated model. This Water Resources Management Plan will then be updated to include thenew financing program. In the interim, this program will continue to be the basis for financingof the City’s system needs. Appendix A describes the trunk fund process and details the ratescharged.Funding for capital improvements within the trunk storm sewer system which serve the olderportions of the City may be obtained through the surface water management utility fee, orassessed to benefiting property. The city also uses its General Fund to pay for miscellaneousoperations and maintenance programs and projects.Lakeville Water Resources Management Plan Page 7-6

This Plan, along with its capital improvement and implementation programs, combined with theexisting Surface Water Management Utility Fund, Trunk Area Charges, and other funding sourcesgives the City adequate funding tools to correct current and future problems.7.5 DESIGN STANDARDSSection 5 presents the City’s stormwater management related regulations and design standards.7.6 ORDINANCE IMPLEMENTATION AND OFFICIAL CONTROLSThe City’s current ordinances and official controls are described in Section 5, and needs andissues are addressed in Section 6. The City has three important issues to address with regard toits official controls.First, the cities and townships within the VRWJPO who do not adopt the VRWJPO Standardswill lose permitting authority for water related development and projects. The City of Lakevilleexpects to retain jurisdiction and permitting authority over development in Lakeville via thisPlan’s policies and its implementation tasks. Lakeville Policies presented in this plan areintended to be consistent with the VRWJPO Policies presented in the 2005 Vermillion RiverWatershed Joint Powers Organization Watershed Management Plan as they relate to the City ofLakeville.Secondly, the City’s loading assessment and Nondegradation Report were completed assumingthat future BMP implementation would follow the VRWJPO Standards (VRWJPO, 2006) formost of the city, with the exception of the South Creek watershed, which would continue tofollow the more stringent volume control requirements established in the City of Lakeville SouthCreek Management Plan.Thirdly, the City must implement the policies and work toward the goals of the Black DogWatershed Management Organization. In its revision of ordinances the City will work to ensurethat its controls meet the policies and standards specified in the BDWMO Water ManagementPlan (2006).Lakeville Water Resources Management Plan Page 7-7

As part of the implementation of this Plan the City will undertake the revision of CityOrdinances, procedures, and policies, such that they are consistent with the:1. Vermillion River Watershed Joint Powers Organization Watershed Standards adoptedOctober 20062. Black Dog Watershed Management Organization Watershed Management Planadopted May 20023. City of Lakeville MS4 Permit SWPPPThese revisions will help ensure the following:Receiving water quality should be improved for lakes, wetlands and streams in Lakeville.Channel erosion and stream morphology changes will be controlled.Further protection will be provided for the physical and biological integrity of the stream andwetland corridors.Temperature changes for trout streams and their tributaries will be mitigated and changes inflow will be controlled.Controlled bounce and duration of inundation in the city’s wetlands and preservation of thefunctions and values for each type of wetland classification.The standards will be applied, where possible, to redevelopment projects to mitigate pastincreases in storm water runoff volume and further improve receiving water quality andhabitat.The City will retain permitting authority for development and water resource relatedprojects.Illicit discharge to storm sewers will be minimized or eliminated.Lakeville Water Resources Management Plan Page 7-8

7.7 CAPITAL IMPROVEMENT PROGRAM AND PRIORITIESMany of the implementation items listed in Tables 7.1 -7.12 are taken from the City’s SWPPPfor its MS4 NPDES permit. With available funding, implementation tasks will be addressed perthe estimated schedule presented here and in the SWPPP.Table 7.1.City of Lakeville Water Resources Implementation ProgramCapital Improvement ProjectsProject # Project Description Cost Estimate*CIP-1Lake Marion ChannelStabilization Project$300,000PotentialFundingSourcesStorm SewerTrunk FundProposedYear(s)2009-2010* Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes onlysince many of the cost estimates may not be based on engineering feasibility reports.Table 7.2.City of Lakeville Water Resources Implementation ProgramStudiesProject #S-1S-2SWP-9S-3S-4S-5Project DescriptionCostEstimate*Ordinance review and$5,000developmentStormwater System Hydrologic$180,000ModelCooperate with the MPCA andothers toward TMDL development $20,000and implementationDevelop BMP contaminant loadreduction models to trackreductions resulting from BMP $80,000implementation, as required bythe MPCALee Lake TMDL Implementation$10,000PlanLakeville Wetland Management$35,000Plan UpdateTOTAL $300,000PotentialFundingSourcesGeneralFundStorm SewerTrunk FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundProposedYear(s)20082009-20102008-20102010* Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.20112013Lakeville Water Resources Management Plan Page 7-9

Table 7.3.City of Lakeville Water Resources Implementation ProgramOfficial ControlsProject # Project Description Cost Estimate*OC-1OC-2SWP-4a-1SWP-3b-1SWP-3c-1SWP-4b-1,4c-1SWP-4e-1SWP-4f-1SWP-4d-1,5a-1SWP-8Revise stormwater managementordinanceRevise wetland managementordinanceReview/revise existing gradingdrainage and erosion controlordinanceDevelop regulatory mechanismprohibiting non-storm waterdischargesProgram to detect and addressillegal dumpingConstruction site erosioncontrol enforcementEstablishment of procedures forthe receipt and consideration ofreports of stormwaternoncomplianceConstruction erosion controland site waste disposalenforcementDevelopment plan reviewEvaluate proposed stormwaterinfiltration projects withinSource Water Protection Areas$20,000$10,000$5,000$5,000$5,000/year$25,000/year$2,500/year$5,000/year$25,000/year$5,000/yearPotentialFundingSourcesSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundSurface WaterFundProposedYear(s)20082013200820082008-20172008-201720082008-20172008-20172008-2017*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-10

Table 7.4.City of Lakeville Water Resources Implementation ProgramPublic Education, Outreach, Participation, and InvolvementProject # Project Description Cost Estimate*SWP-1a-1 Distribute educational materials $5,000/yearSWP-1b-1SWP-1c-1Implement educationalactivitiesDevelop internet siteinformation$1,000/year$1,500/yearSWP-1c-2 Encourage public participation $1,000/yearSWP-1c-3SWP-1c-4SWP-1c-5SWP-1c-6SWP-1d-1Illicit discharge education forresidents and staffConstruction site runoffeducationPost construction stormwaterpublicationPollution prevention & goodhousekeeping for City staffCoordination of educationalprogramming with otheragencies$1,500/year$1,500/year$500/year$1,000/year$500/yearSWP-1e-1 Conduct annual meeting $500/yearSWP-2a-1SWP-2b-1SWP-2c-1SWP-3d-1Comply with public noticerequirementsSolicit public input on theSWPPPConsider and record publicinputPublic and staff illicit dischargeinformation programTOTAL$500/year$2,000/year$500/year$1,000/year$18,000/yearPotentialFundingSourcesSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundProposedYear(s)2008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-2017*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-11

Table 7.5.Project#Valley Lake ProjectsCity of Lakeville Water Resources Implementation ProgramLakes Management ProgramProject DescriptionCostEstimate($)*Potential FundingSourcesYear(s)V-1 Water Quality Improvement Projects 4,000 Surface Water Fund 2008-2017V-2 Apply crushed corn for algae control. 1,000 Surface Water Fund 2008-2017V-4 Operate Valley Lake Aeration System 600 Surface Water Fund 2008-2017V-5 Prepare educational materials/final report 400 Surface Water Fund 2008-2017V-6 Continue monitoring program 550 Surface Water Fund 2008-2017Orchard Lake ProjectsO-1 Nutrient reduction education anddemonstration projects3,000 Surface Water Fund 2008-2017O-2 Native aquatic plant management 4,200 Surface Water Fund 2008-2017O-3 Curlyleaf pondweed control 31,850 Surface Water Fund 2008-2017O-4 Contingency plans for Eurasianwatermilfoil invasion1,000 Surface Water Fund 2008-2017O-5 Stunted panfish control with gamefishadditions1,000 Surface Water Fund 2008-2017O-6 Shoreline management and watershedmonitoring3,000 Surface Water Fund 2008-2017O-7 Continue lake testing program 1,000 Surface Water Fund 2008-2017O-8 Update lake management plan 6,800 Surface Water Fund 2008-2017Lee Lake ProjectsL-1 Barley straw 5,600 Surface Water Fund 2008-2017L-2 Curlyleaf pondweed control/nutrient2008-20172,000 Surface Water FundreductionL-3 Adopt-A-Pond/Public information and2008-20171,500 Surface Water FundeducationL-4 Continue monitoring program 1,000 Surface Water Fund 2008-2017L-5 Year end summary report, public meeting 3,000 Surface Water Fund 2008-2017L-6 Produce lake management plan 7,900 Surface Water Fund 2008-2017Lake Marion Quality ProjectsM-1 Aquatic plant surveys 4,800 Surface Water Fund 2008-2017M-2 Mid summer aquatic plant managementand Milfoil control program3,700 Surface Water Fund 2008-2017M-3 Milfoil control program 4,800 Surface Water Fund 2008-2017M-4 Nuisance plant management 1,500 Surface Water Fund 2008-2017M-5 Winter aeration program 400 Surface Water Fund 2008-2017M-6 Continue monitoring program 550 Surface Water Fund 2008-2017TOTAL95,150/year*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planningpurposes only.Lakeville Water Resources Management Plan Page 7-12

Table 7.6.City of Lakeville Water Resources Implementation ProgramOperation and Maintenance ProgramsProject # Project Description Cost Estimate*SWP-3a-1 Maintain storm sewer system map $2,000/yearSWP-5c-1SWP-6a-2SWP-6b-2SWP-6b-3SWP-6b-4SWP-6b-5SWP-6b-6Long-term operation andmaintenance of BMPs: inspectionand documentationStreet and parking lot sweepingprogramAnnual inspection of all structuralpollution control devices.Inspection of a minimum of 20% ofthe MS4 outfalls, anddocumentationInspection of City stockpile, storage,and material handling areasInspection follow-up, determinationof necessary action andimplementation of correctivemeasuresReporting and retention ofinspections and responses$50,000/year$150,000/year$5,000/year$6,500/year$1,500/year$20,000/year$5,000/yearSWP-6b-7 Evaluation of inspection frequency $500/yearSWP-6b-8Landscaping and lawn care practicesreview$500/yearSWP-6b-9 Road salt application review $2,000/yearOM-1Storm Pond Dredging andMaintenance$75,000/yearOM-2 Storm drain system cleaning $60,000/yearOM-3 Hazardous material management $1,500/yearSWP-1 Develop MS4-SWPPP $3,000/yearTOTAL$382,500/yearPotentialFundingSourcesGeneralFundSurfaceWater FundGeneralFundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundSurfaceWater FundGeneralFundSurfaceWater FundGeneralFundGeneralFundSurfaceWater FundProposedYear(s)2008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-20172008-2017*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-13

Table 7.7.City of Lakeville Water Resources Implementation Program TimelineCIPProjectCIP-1: Lake Marion ChannelStabilization ProjectEstimated Costs by Year* in thousands of dollars2008 2009 2010 2011 2012 2013 2014 2015 2016 2017150 150TOTAL 150 150*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Table 7.8.City of Lakeville Water Resources Implementation Program TimelineStudiesProjectS-1: Ordinance review and development 5S-2: Stormwater System Hydrologic Model 75 75SWP-9: Cooperate with the MPCA andothers toward TMDL development andimplementationS-3: Develop BMP contaminant loadreduction models to track reductionsresulting from BMP implementation, asrequired by the MPCAEstimated Costs by Year* in thousands of dollars2008 2009 2010 2011 2012 2013 2014 2015 2016 20177 7 7 7S-4: Lee Lake TMDL Implementation Plan 10S-5: Lakeville Wetland Management PlanUpdateTOTAL 12 82 162 17 35*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.8035Lakeville Water Resources Management Plan Page 7-14P:\Mpls\23 MN\19\2319A29 Lakeville Stormwater Plan Revisions\WorkFiles\InProgress\SECTION 7 Lakeville Plan - Implementation Program.doc

Table 7.9.City of Lakeville Water Resources Implementation Program TimelineOfficial ControlsProjectOC-1: Revise stormwater managementordinanceEstimated Costs by Year* in thousands of dollars2008 2009 2010 2011 2012 2013 2014 2015 2016 2017OC-2: Revise wetland management ordinance 10SWP-4a-1: Review/revise existing gradingdrainage and erosion control ordinanceSWP-3b-1: Develop regulatory mechanismprohibiting non-storm water dischargesSWP-3c-1: Program to detect and addressillegal dumpingSWP-4b-1, 4c-1: Construction site erosioncontrol enforcementSWP-4e-1: Establishment of procedures for thereceipt and consideration of reports ofstormwater noncomplianceSWP-4f-1: Construction erosion control andsite waste disposal enforcement20555 5 5 5 5 5 5 5 5 525 25 25 25 25 25 25 25 25 252.55 5 5 5 5 5 5 5 5 5SWP-4d-1, 5a-1: Development plan review 25 25 25 25 25 25 25 25 25 25SWP-8: Evaluate proposed stormwaterinfiltration projects within Source WaterProtection Areas5 5 5 5 5 5 5 5 5 5TOTAL 97.5 65 65 65 65 75 65 65 65 65*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-15P:\Mpls\23 MN\19\2319A29 Lakeville Stormwater Plan Revisions\WorkFiles\InProgress\SECTION 7 Lakeville Plan - Implementation Program.doc

Table 7.10.City of Lakeville Water Resources Implementation Program TimelinePublic Education, Outreach, Participation and InvolvementProject NumberEstimated Costs by Year* in thousands of dollars2008 2009 2010 2011 2012 2013 2014 2015 2016 2017SWP-1a-1: Distribute educational materials 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-1b-1: Implement educational activities 1 1 1 1 1 1 1 1 1 1SWP-1c-1: Develop internet site information 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5SWP-1c-2: Encourage public participation 1 1 1 1 1 1 1 1 1 1SWP-1c-3: Illicit discharge education forresidents and staff1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5SWP-1c-4: Construction site runoff education 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5SWP-1c-5: Post construction stormwaterpublicationSWP-1c-6: Pollution prevention & goodhousekeeping for City staffSWP-1d-1: Coordination of educationalprogramming with other agencies0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.51 1 1 1 1 1 1 1 1 10.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-1e-1: Conduct annual meeting 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-2a-1: Comply with public noticerequirements0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-2b-1: Solicit public input on the SWPPP 2 2 2 2 2 2 2 2 2 2SWP-2c-1: Consider and record public input 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-3d-1: Public and staff illicit dischargeinformation program1 1 1 1 1 1 1 1 1 1TOTAL 18 18 18 18 18 18 18 18 18 18*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-16P:\Mpls\23 MN\19\2319A29 Lakeville Stormwater Plan Revisions\WorkFiles\InProgress\SECTION 7 Lakeville Plan - Implementation Program.doc

Table 7.11. City of Lakeville Water Resources Implementation Program TimelineLakes Management ProgramProject NumberEstimated Costs by Year* in thousands of dollars2008 2009 2010 2011 2012 2013 2014 2015 2016 2017Valley Lake ProjectsV-1: Water Quality Improvement Projects 4 4 4 4 4 4 4 4 4 4V-2: Apply crushed corn for algae control. 1 1 1 1 1 1 1 1 1 1V-3: Operate of Valley Lake Aeration System 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6V-4: Prepare educational materials/final report 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4V-5: Continue monitoring program 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55Orchard Lake ProjectsO-1: Nutrient education /demo projects 3 3 3 3 3 3 3 3 3 3O-2: Native aquatic plant management 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2O-3: Curlyleaf pondweed control 31.85 31.85 31.85 31.85 31.85 31.85 31.85 31.85 31.85 31.85O-4: Contingency plan for E. .milfoil invasion. 1 1 1 1 1 1 1 1 1 1O-5: Control panfish with gamefish additions 1 1 1 1 1 1 1 1 1 1O-6: Shoreline mgmt/watershed monitoring 3 3 3 3 3 3 3 3 3 3O-7: Continue lake testing program 1 1 1 1 1 1 1 1 1 1O-8: Update lake management plan 6.8 6.8 6.8 6.8 6.8 6.8 6.8 6.8 6.8 6.8Lee Lake ProjectsL-1: Barley straw 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6L-2: Curlyleaf weed control/nutrient reduction 2 2 2 2 2 2 2 2 2 2L-3: Adopt-A-Pond/Public education 1,5 1,5 1,5 1,5 1,5 1,5 1,5 1,5 1,5 1,5L-4: Continue monitoring program 1 1 1 1 1 1 1 1 1 1L-5: Year end summary report, public meeting 3 3 3 3 3 3 3 3 3 3L-6: Produce lake management plan 7.9 7.9 7.9 7.9 7.9 7.9 7.9 7.9 7.9 7.9Lake Marion ProjectsM-1: Aquatic plant surveys 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8M-2: Aquatic plant mgmt/Milfoil control 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7M-3: Milfoil control program 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8M-4: Nuisance plant management 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5M-5: Winter aeration program 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4M-6: Continue monitoring program 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55TOTAL 95.15 95.15 95.15 95.15 95.15 95.15 95.15 95.15 95.15 95.15*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-17P:\Mpls\23 MN\19\2319A29 Lakeville Stormwater Plan Revisions\WorkFiles\InProgress\SECTION 7 Lakeville Plan - Implementation Program.doc

Table 7.12.City of Lakeville Water Resources Implementation Program TimelineOperations and Maintenance ProgramsProject NumberEstimated Costs by Year* in thousands of dollars2008 2009 2010 2011 2012 2013 2014 2015 2016 2017SWP-3a-1: Maintain storm sewer system map. 2 2 2 2 2 2 2 2 2 2SWP-5c-1: Long-term operation and maintenance ofBMPs: inspection and documentation.50 50 50 50 50 50 50 50 50 50SWP-6a-2: Street and parking lot sweeping program. 150 150 150 150 150 150 150 150 150 150SWP-6b-2: Annual inspection of all structuralpollution control devices.SWP-6b-3: Inspection of a minimum of 20% of thems4 outfalls, and documentation.SWP-6b-4: Inspection of City stockpile, storage, andmaterial handling areasSWP-6b-5: Inspection follow-up, determination ofnecessary action and implementation of correctivemeasures.SWP-6b-6: Reporting and retention of inspections andresponses.5 5 5 5 5 5 5 5 5 56.5 6.5 6.5 6.5 6.5 6.5 6.5 6.5 6.5 6.51.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.520 20 20 20 20 20 20 20 20 205 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-6b-7: Evaluation of inspection frequency. 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-6b-8: Landscaping and lawn care practicesreview.0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5SWP-6b-9: Road salt application review. 2 2 2 2 2 2 2 2 2 2OM-1: Storm Pond Dredging and Maintenance 75 75 75 75 75 75 75 75 75 75OM-2: Storm drain system cleaning. 60 60 60 60 60 60 60 60 60 60OM-3: Hazardous material management. 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5SWP-1: Develop MS4-SWPPP 3 3 3 3 3 3 3 3 3 3TOTAL 382.5 382.5 382.5 382.5 382.5 382.5 382.5 382.5 382.5 382.5*Cost estimates are based on 2007 dollars, do not account for inflation, and are for planning purposes only.Lakeville Water Resources Management Plan Page 7-18P:\Mpls\23 MN\19\2319A29 Lakeville Stormwater Plan Revisions\WorkFiles\InProgress\SECTION 7 Lakeville Plan - Implementation Program.doc

8.0 ReferencesBlack Dog Watershed Management Organization, Watershed Management Plan, May 2002,Prepared by Barr Engineering Company.Black Dog Watershed Management Organization, Crystal and Keller Lake Use AttainabilityAnalysis Diagnostic Feasibility Study: Water Quality Issues and Potential Restorative Measures,July 2003, Prepared by Barr Engineering Company.Black Dog Watershed Management Organization, 2006 Habitat Monitoring of Strategic WaterResources, March 2007, Prepared by Barr Engineering Co.City of Apple Valley, Apple Valley Stormwater Management Plan (2007), Prepared byBonestroo, Rosene, Anderlik & Associates.City of Burnsville, Burnsville Water Resources Management Plan, (revised 2008), Prepared byShort Elliott Hendrickson Inc.City of Lakeville, Nondegradation Report Submittal to the Minnesota Pollution Control Agency forSelected MS4 Permit Requirements, July 2007, Prepared by Barr Engineering Company.City of Lakeville, Environmental Resources 2006 Annual Report, March 2007.City of Lakeville, Wetland Management Plan, May 2003, Prepared by WSB & Associates, Inc.City of Lakeville, South Creek Management Plan, July 2000.City of Lakeville, Orchard Lake Diagnostic-Feasibility Study: Water Quality Issues and PotentialRestorative Measures, April 1999, Prepared by Barr Engineering Company.City of Lakeville, Lake Marion Curlyleaf Pondweed Control Study, July 1998, Prepared by BarrEngineering Co.City of Lakeville, Lake Marion Diagnostic-Feasibility Study: Water Quality Issues and PotentialRestorative Measures, March 1997, Prepared by Barr Engineering Company.City of Lakeville, Stormwater Management Plan, July 1995, Prepared by Barr EngineeringCompany.City of Plymouth July/August 2007 “Environmental Extra”.Climatology Working Group Website. http://climate.umn.edu, andhttp://climate.umn.edu/doc/twin_cities/twin_cities.htmFederal Emergency Management Agency, Federal Insurance Administration. 1980. Flood InsuranceStudy, City of Lakeville, Minnesota, Dakota County, Community Number 270107.Lakeville Area Historical Society, A Glimpse of Lakeville's Past, 2004.Metropolitan Council, Local Planning Handbook, September 2005.Lakeville Water Resources Management Plan Page 8-1

Midwestern Regional Climate Center websitehttp://mcc.sws.uiuc.edu/climate_midwest/mwclimate_data_summaries.htm#Minnesota Board of Water and Soil Resources. 2000. Dakota County Groundwater Protection Plan.Minnesota Department of Natural Resources. 1997. Minnesota County Biological Survey NaturalCommunity and Rare Species of Dakota County, Minnesota.Minnesota Department of Natural Resources. Lake Finder Website.www.dnr.state.mn.us/lakefind/index.html.Minnesota Department of Natural Resources. Climate website.http://www.dnr.state.mn.us/climate/index.htmlMinnesota Geological Survey. 1990. Geologic Atlas of Dakota County, Minnesota. County AtlasSeries Atlas C-6.Minnesota Pollution Control Agency, Guidance Manual for Assessing the Quality of MinnesotaSurface Waters for the Determination of Impairment, October 2005.Minnesota Pollution Control Agency, Minnesota Lake Water Quality Assessment Report:Developing Nutrient Criteria, Third Edition, September 2005.Minnesota Pollution Control Agency, Minnesota Stormwater Manual, Version 1.0, November2005.Minnesota Pollution Control Agency, 2006 Final List of Impaired Waters, August 2006.Minnesota Pollution Control Agency, 2008 Draft List of Impaired Waters, September 2007.Minnesota Pollution Control Agency, Summer 2007 “Minnesota Environment.”Minnesota Pollution Control Agency, website www.pca.state.mn.usSoil and Water Conservation Society. 2003. Conservation Implications of Climate Change: SoilErosion and Runoff from Cropland.U.S. Department of Agriculture.1944. Miscellaneous Publication 204. Rainfall intensity-frequencydata.U.S. Department of Agriculture, Natural Resource Conservation Service (NRCS). 1975. MinnesotaHydrology Guide.U.S. Department of Agriculture, Soil Conservation Service (SCS). 1971. National EngineeringHandbook.U.S. Department of Agriculture, Soil Conservation Service (SCS). 1983. Soil Survey of DakotaCounty, Minnesota.Vermillion River Watershed Joint Powers Organization, Watershed Management Plan,November 3, 2005.Lakeville Water Resources Management Plan Page 8-2

Vermillion River Watershed Joint Powers Organization, Standards, February 2008, amended.Vermillion River Watershed Joint Powers Organization, Watershed Rules, March 2007.Lakeville Water Resources Management Plan Page 8-3