Minnesota Water Resources Conference - Water Resources Center ...

Concurrent Sessions V 1:15–2:45
BOOK OF ABSTRACTS
Wednesday, Tuesday, October 24 28 23
Track E: Storm Water Monitoring: Cool Case Studies and Updating Particle Size Data
Paired-Watershed Assessment of Retrofitted Stormwater Volume Reduction BMPs
Kristy Treichel, City of River Falls, ktreichel@rfcity.org; Rich Brasch, Bonestroo; and Reid Wronksi, City of River Falls
This presentation reports on retrofitting small-scale volume reduction practices into an older city
neighborhood. The City, Trout Unlimited, Kinnickinnic River Land Trust, Kinnickinnic Priority Watershed,
WiDNR, and private property owners worked together on this demonstration project with the following
objectives:
1. Survey the willingness of property owners to make changes on their property to better manage stormwater.
2. Design and implement a variety of retrofitted infiltration BMPs within the public right-of-way.
3. Monitor stormwater runoff from control and experimental paired-watersheds, before and after BMP
installation.
4. Use project outcomes to:
a. gauge the feasibility of small-scale retrofit practices
b. understand the actual benefits of volume reduction BMPs
c. guide the City’s implementation of infiltration BMPs in other areas
BMPs implemented include:
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Mowable grass infiltration basins
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Rainwater gardens
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Porous concrete gutters
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Porous paver alleys
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Rain barrels
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Rain gutter redirection
Local Urban Stormwater Monitoring, Results and Implications for Future Management
Katie Huser, Capitol Region Watershed District, katie@captiolregionwd.org; and Melissa Baker, Capitol Region Watershed
District
Capitol Region Watershed District (CRWD), located in Ramsey County, is completely urbanized, with 42%
coverage by impervious surfaces and is drained almost solely by storm sewers. CRWD began its water quality
monitoring program in 2005 with 8 stormwater water quality monitoring stations and has grown to 18 stations
in 2008. At each station, flow is measured continuously and composite water quality samples are collected
during storms and baseflow. Water samples are analyzed for nutrients, solids and metals. Results are discussed
for 10 subwatershed stations. Pollutant loadings and yields are calculated for TP and TSS. With no water
quality standards for stormwater, flow weighted average concentrations are compared to concentrations in the
receiving waters (Mississippi River), to surface water quality standards and national averages for stormwater.
CRWD is now assessing how monitoring data compares to model predictions and what our results mean for
load reductions required by future TMDLs.
Minnesota Water Resources Conference, October 27–28, 2008 74