Three Waters Final 2008 Strategic Plan - Watercare

ThreeWatersFinal 2008StrategicPlanDecember 2008DEC2008

DocumentContentsAuckland Three Waters StrategicPlanning ProgrammeFinal 2008 Strategic PlanDecember 2008Introduction Overview of strategy development and purposes of this document 1Part AStrategic Plan KeyMessagesSummary of key findings 3Satisfying urban and rural three waters needs 6Part BGeneral backgroundto the strategyRegional drivers for strategy developmentThe environment we want to protectKey assets we want to look to look afterPlanning for climate change10151719Part CIntegrating thedelivery of ThreeWaters ServicesMaximising efficiency by integrated delivery of three waters servicesIntegrated planning in a broader context2224Part DWastewaterFacts and figures - our current situationQuestions and answers for the futureFuture regional wastewater optionsMulti criteria analysisPreliminary outcomes2629303844Part EWater SupplyFacts and figures - our current situationAuckland Water Management PlanQuestions and answers for the futureFuture water source optionsA water efficiency scenarioPreliminary outcomes505556626566Part FStormwaterIssues and Matters to be addressed 67Part GSummarySummary 71Final 2008 Strategic Plan – December 2008

The Three Waters StrategicPlanning Programme wasundertaken to tackle the bigissues underpinning a region-wideapproach to our region’s futurerequirements for the provisionof services in all “three waters” –drinking water, stormwater andwastewater. Each of the threewaters is, of course, inextricablylinked to the others.Watercare – the region’s bulk water and wastewaterservice provider – is pleased to have had the opportunityto lead the participating organisations through theintegrated thinking required for the future.This programme has raised some real and practical issuesthat must be faced by planners, policy-makers, politiciansand – crucially – the general public as Auckland plans forthe next 100 years.In drinking water we need to encourage more efficientuse. This is in the best interests of the environment butalso may defer the need for major capital expenditure.Minimising leaks in water supply networks andencouraging consumers to use water more efficientlycould have an impact on the timing of future capitalprojects – including the introduction of a new watersource for the region.Other options which need to be considered in this contextare the substitution of rainwater in the place of A-gradedrinking water for certain purposes, perhaps includingtoilet flushing, and the exploration of the possible use ofRodneyDistrictWaitakereCityNorthShore CityAucklandCityManukauCityPapakuraDistrictstormwater or treated wastewater in specific industrialprocesses. Some of these options may appear challengingand there are practical issues to be considered. Howeverwe believe that outlining them in this report represents animportant step in engaging the wider community for thenext stages.Another significant issue addressed in this report is thetransfer and treatment of wastewater. The work done inthis report indicates that a combination of our region’stwo wastewater treatment plants – in Mangere, to thesouth, and Rosedale, to the north – will be required forthe foreseeable future. Sewer upgrades, including theconstruction of a new pipeline from central Aucklandto Mangere, will be required. The approach taken tointegrating land use planning and the management ofstormwater will be critical.There will be considerable community and politicalinterest in all of these issues. The increased environmentalstandards required by the public will be reflected in futureinfrastructure development.Ultimately – of course – planning can only go so far. Thenext important stage of the Three Waters programme isthe implementation phase, when each of the organisationswith responsibility for key components of this region-widepicture picks up the challenge and delivers the results thatAucklanders need and deserve in the future.K. M. FordChief ExecutiveWatercare Services LimitedRodney DistrictNorth Shore CityWaitakere CityAuckland CityManukau CityPapakura DistrictFranklin DistrictFranklinDistrictOur RegionOverview A vision weof can the allStrategy shareDevelopmentA list of approveddemandmanagement toolsOur communitiesdemand improvingenvironmentalstandards.Future watersupply, wastewaterand stormwaterservices willOur reflect communities this.demand improvingenvironmentalstandards.Future watersupply, wastewaterand stormwaterservices willreflect this.1Final 2008 Strategic Plan – December 2008

Satisfyingurban andrural threewaters needsA 2008 snapshotand a possiblefutureUrbanRural2008 Possible future 2008 Possible futureWater supply Almost 100%bulk regionalsupply, treatmentand distribution.Unrestricteddemand.Generally as 2008with potentialfor up to 25%localised use ofwastewater andstormwater asalternatives tonew sources andadditional demandmanagement.Combinationof individualproperty andlocal communitysupply with somerestrictions ondemand to reflectsupply availability.Generally as2008, withprobable linkageto regional supplynetworks for somecommunitiesbased on localityspecific benefit -cost analyses.Wastewater Almost 100%centralisedcollection,treatment anddisposal andvery limitedbeneficial use.Generally as 2008,with potentialfor additionalbeneficial use,depending oncommunityand industryacceptability andphysical feasibility.Combination ofindividual andlocal communitycollect ion,treatment anddisposal systemsand no significantbeneficial use.Generally as 2008,with probablelinkage to regionalnetworks for somecommunitiesbased on localityspecific benefit -cost analyses.Stormwater100% localcollection,treatment anddisposal and nosignificant reuse.Main focus onflood protectionand the useof bottom ofcatchmentdevices.Generally as 2008but potential forsignificant localuse as alternativewater source.Greater integratedcatchmentplanning andincreasingfocus on streamprotection andcontrols at source.100% localcollection,treatment anddisposal with roofwater used forwater supply inmainly rural areas.Likely to remaingenerally as 2008but roof water usecould decrease.WastewatersolidsBiosolidsbeneficiallyused for landrehabilitation,as practicable.Remainder tolandfill.Some relianceon landfill willcontinue butpreferred methodis beneficialuse for landrehabilitationand/or fertilisersubstitute.Some communitysystems rely onlandfill. Onsitetreatmentsystems requiresolids disposal tourban wastewatertreatment plantsor rural septagedisposal facilities.Likely to remaingenerally as 2008with possibletrend to greaterreliance on use ofurban wastewaterbecause ofconsentingdifficulties forrural facilities.Integrated threewaters solutionsNo significantintegration withinurban areas,however, somelinks in urbanareas.Integration toextent practicableto optimiseefficiency andcost effectiveness.Localised roofwater use but noother significantintegration.Integration toextent practicableto optimiseefficiency andcost effectiveness.6Urban - rurallinkagesLimited linkagesfrom urbanto rural.Greater relianceon rural areasfor biosolidsbeneficial use ordisposal.Some septageto urbanWWTP. Ruralwater suppliessupplementedfrom urbansupply during dryweather.Generally asabove, withsome rural areasconnected tourban areas asappropriate.Final 2008 Strategic Plan – December 2008

Part BGeneralBackgroundto theStrategy7Final 2008 Strategic Plan – December 2008

Working inpartnershipwithMaoriKia pai te whakatere i te wakakei pariparia e te tai, ka morehu te kura neiSteer with skill the canoe, lest the outgoing tide endanger the lives onboardImportant principles used in the Strategic Plan:For Maori, linking the past, the present and the future isan important concept of life. We, too, must learn from thepast in planning our future.We must understand and exercise the principles ofkaitiakitanga (guardianship) so those who follow canenjoy what we enjoy today.We must establish the right Tikanga (protocols) thatwill enable us to deliver water supply, wastewater andstormwater services in an integrated and sustainable way.8Final 2008 Strategic Plan – December 2008

4,000,0003,500,000Providing for GrowthWhy is this ThreeWaters StrategicPlan necessarynow?3,000,000Population2,500,0002,000,0001,500,0001,000,000500,00001920 1940CensusForecastForecast prepared by Shearer Consulting after consulting withsenior planners of participating organisations and the ARC.1960 1980 2000 2020 2040 2060 2080 2100The above graph is indicative only, particularly from about 2030 onwards. Its primary purpose is to enable a bestassessment of likely future infrastucture needs. Actual needs will be reviewed progressively to reflect updatedinformation before investment decisions are made.and three waters providers must ensure we …YearsWater supply,wastewater andstormwaterservices willall need to:• Serve up to2.5 timesthe presentpopulationby 2100• Satisfychanging legalrequirements• Deliver levelsof serviceagreed withthe communityProtect our health and environmentDeliver services sustainablyMaximise efficiency through integrateddelivery of three waters servicesSome issuesrequire urgentattentionPlanning for allissues needs tostart nowPlan for the effects of climatechangeMaximise use of existing assetsEnsure flexibility to meet changingfuture needsAnd we mustlook after bothurban and ruralcommunitiesAt all times during the development of the Strategic Plan, emphasiswas placed on the need to balance social, cultural, environmental andeconomic considerations.9Final 2008 Strategic Plan – December 2008

There isparticularurgency toaddress keywastewaterneeds now...Many household and localwastewater pipes leak and overloadthe networksSome major sewers are near or atcapacity in Central Auckland andsome cannot be maintained becausethey flow full for significant periodsof timeTo avoid dry weather wastewateroverflows that could occur almostdaily in less than 30 yearsFor both public health and environmental reasons, it willbe essential for these issues to be addressedRefer to Watercare AssetManagement Plan 2008The Mangere Wastewater TreatmentPlant will reach its flow capacity inabout 2027, at projected populationgrowth ratesManaging discharges from boththe Mangere and Rosedale plantsto protect the environment willcontinue to be very importantLimiting nitrogen and pathogendischarges into the environment, inparticular, will be essentialSomeWastewaterdecisions arerequired byJune 2009Major works will be required toaddress these issues, includingtreatment plant upgrading and theduplication of major trunk sewersnear the Mangere WWTP (to allowaccess for maintenance purposes).In the longer term, either possiblerelocation of the existing shorelinedischarge in the Manukau Harbouror diversion of some flows awayfrom the Mangere WWTP will berequired.Estimated capital costs for trunk components of possiblecomplete schemes range from $3 to $4 billion over theperiod to 2100, excluding trunk sewer replacement and alllocal costs.None of the above issues can be addressed by waterdemand management, low impact design, on-sitewastewater treatment or local treatment plants. Theseoptions may all have a role to play, but in associationwith the continued use of existing infrastructure andupgrading works10Final 2008 Strategic Plan – December 2008

Managing community demand forwater to balance needs, costs andbenefitsReducing water loss and wastageand particularly leaks in pipenetworksFinding ways of using stormwatersafely, instead of piped supplyThere areequallyimportantwater supplyissues to beaddressed,including...Finding safe uses for treatedwastewater instead of piped supplyEnsuring long-term security ofsupply for North Shore City andparts of Rodney DistrictMaking provision to supplement ruralwater supplies in dry periodsRefer to Three Waters IssuesReport TW2 for detailsMaking sure we have enough watertreatment capacity to meet mediumterm needsSecuring sufficient water sources tomeet long-term needsAnd we need to look closely atwhether we charge enough for waterReductions in potable water use will not reduce the costs of wastewater management significantly, at least in thenext 20 to 30 years. Collection pipes are designed to carry a wet weather allowance and dry weather flows are a smallcomponent of this total flow. Wastewater treatment depends mainly on contaminant loads, which are dependant onconnected populations, but relatively unaffected by wastewater volume.The successof waterefficiency willdepend oncommunityattitudes11Final 2008 Strategic Plan – December 2008

Regionallyconsistentstormwaterpolicy willbe keyTo allow the prevention or controlof stormwater contaminants atsourceTo reduce sediment discharges tothe environmentTo encourage stormwater use as asubstitute for mains water supplyAnd so willa regionalbiosolidsmanagementplanAnd for all threewaters, well thoughtout central, regionaland local governmentplanning policiesand infrastructuredesign standards willbe essential if we areto minimise futureproblemsBuilding Act, LGA, RMARegional PlanningA regionalThree Waterspolicy grouphas beenformed tohelp addresspolicy issuesNational StandardsAuckland Regional Infrastructure Design Standards Manual12Final 2008 Strategic Plan – December 2008

Towards sustainabilityWe will ensure sustainability by:addressing the management of water, land andother natural resources as an integrated whole;balancing social, cultural, environmental andeconomic objectives equitably;avoiding waste, and where it cannot be avoided,minimising waste by reduction at source, reuseand/or recycling, where practicable;minimising energy use;OurThreeWatersVisionmanaging the requirements for new water sourcesby researching and implementing wastewater andstormwater reuse initiatives, where appropriate andpracticable;promoting community guardianship of naturalresources that affect them;promoting kaitiakitanga (guardianship); andseeking solutions to immediate problems thatcontribute to sustainable longer-term outcomes.69159258212305495Key DriverNo.1 -Providingfor growthProjectedgrowth to 2100 bydistrict1912964802006 census2046 forecast*2100 forecast**42566510795787141332527845445589Regionalgrowth of upto 2.5 timesour PICTURE present TOpopulation COMEcould occurby 2100*Population forecasts for city and district council areas in thousands. Source: Statistics New Zealand.** Population forecast after 2050 by Shearer Consulting.13Final 2008 Strategic Plan – December 2008

Key DriverNo. 2 –Meetingwide-ranginglegalrequirementsKey requirements• Aligning Three WatersStrategic Plan with Long TermCouncil Community Plans.• Lobbying central governmentto change legislation whererequired.• Ensuring consistent regionalpolicy, aligned with outcomesof this strategy• Providing clear guidance onimportant legal requirements• Ensuring consistentinterpretation and applicationof policies.Local Government ActThis Act promotes the accountability of localauthorities to their communities.It provides for local authorities to play a broad rolein promoting the social, economic, environmentaland cultural well-being of their communities,taking a sustainable development approach.It requires local authorities to identify allreasonably practicable options and considerthe benefits and costs of each option in termsof the present and future social, economic,environmental and cultural well-being of thedistrict or region.Building ActThe Act sets performance standards to ensurethat buildings are designed, constructed, andable to be used in ways that promote sustainabledevelopment, including:• the efficient and sustainable use of materials inbuildings; and• the efficient use of water and waterconservation in buildings.Resource Management ActThe purpose of this Act is to promote thesustainable management of natural andphysical resources.It requires the use, development, and protectionof natural and physical resources in a way, or ata rate, which enables people and communities toprovide for their social, economic, and culturalwell-being and for their health and safety while:• Sustaining the potential of natural and physicalresources (excluding minerals) to meet thereasonably foreseeable needs of futuregenerations; and• Safeguarding the life-supporting capacity of air,water, soil, and ecosystems; and• Avoiding, remedying, or mitigating any adverseeffects of activities on the environment.Health ActThe underlying principles of the Act are to provideobligations and tools for city and district councilsand others to ensure the protection of publichealth.Key DriverNo. 3 – Andprovidingthe followinglevels ofserviceWater SupplyPresent drought security design for 1:200 yeardrought with reservoirs drawn down to empty(equivalent to 1:50 with 25% remaining capacity).Minimum of 24 hours storage of treated wateravailable throughout the distribution system.Supplies to meet New Zealand Ministry of HealthDrinking Water Quality standards.WastewaterEnsure pipe capacity to contain dry and wetweather design flows.Wet weather overflows from wastewaterconveyance systems managed to meet resourceconsent conditions and customer expectations.Optimisation of local and trunk network solutions.14We need tobetter informthe communityStormwaterLevels of service determined at local level byTerritorial Authorities and may vary.No regional levels of service to be addressedwithin Three Waters Strategy.Habitable floor levels to be above 1:50 or 1:100year return period storm events.Pipes to provide capacity for between 1:5 and1:20 year return period event.We need to encourage:• Better maintenance of private infrastructure toreduce leakage, in part through more stringent designstandards• Using less water.• Making the use of treated wastewater more acceptablein particular circumstances.• Reducing stormwater contaminants.• Greater use of low impact design techniques.• Improved design and construction standards / policies.• Testing levels of service as appropriate through out theplanning process.Final 2008 Strategic Plan – December 2008

Theenvironmentwe want toprotectSurface water impoundmentsRiver sourcesGroundwater resourcesUrban LakesProtectingthe qualityand values ofour aquaticenvironment isan importantregionalobjective andone that thethree watersproject willcontributetowards.Rural environmentsTo help us do that, weneed to understand theenvironment, and howit is used.Urban StreamsRural community beachesWe have abeautifulenvironmentwe mustprotect forpresentand futuregenerationsDeveloping CatchmentsUrban BeachesReceiving environments for treatedwastewater15Final 2008 Strategic Plan – December 2008

The usesof theenvironmentwe valueUrban water supplyStock wateringHorticultureRODNEYDISTRICTNORTHSHORECITYWAITAKERECITYAUCKLANDCITYMANUKAUCITYPAPAKURADISTRICTFRANKLINDISTRICTWater playTreated wastewater dischargesYachtingTheenvironmentsupplies allour waterRodneyDistrictPossible futureNorthern Ararimu DamNorthShore CityWaikato PipelineWater Treatment PlantSewer Treatment PlantWater CatchmentsCatchmentsOnehunga AquifierUpper Nihotupu DamUpper Huia DamLower Huia DamWaitakereCityWaitakere DamLower Nihotupu DamAucklandCityManukauCityHays Creek DamPapakuraDistrictWairoa DamCosseys DamUpper Mangatawhiri DamMangatawhiri DamWaikatoPipelineWaikato River(Off plan)Possible futureLower Mangatawhiri DamFranklinDistrict16Final 2008 Strategic Plan – December 2008

Approximately 70% of the currentwater supply for the Aucklandregion is provided by sources andtreatment to the south of themain metropolitan area. There arespecific places that are critical tothe successful operation of thebulk water network:• The Ardmore water treatment plant provides 60% of thewater supply for the region. The Huia water treatmentplant provides 25%, with the balance provided from fiveother facilities.• Redoubt Road is a large treated water reservoir complexwhich collects and distributes all southern water.• South to north pipelines carry the majority of regionalwater supplies but areas around Mangere do not havethe benefit of a bulk water ring main.• Supplies to the north of the region are carried over tworoad bridges.The loss of any part of this infrastructure would have amajor negative effect on Aucklanders.Over the past 100 years theinfrastructure that delivers waterin the Auckland region has grownas the population has expanded.For example, the addition of largediameter water pipelines to theWatercare mains network has beena gradual process with, on average,six kilometres of pipe added everyyear for the past 50 years.These assets will last for many years. The lifetime of thepipes will depend on the material they are made fromand where and how they have been installed. Assetmanagement plans record when the pipelines wereinstalled and what they were made from. Reviewingthose combinations of installation and expected livesmeans a forward projection of pipeline replacement orrehabilitation can be forecast.This pattern of installation and asset life will also berecorded and reviewed for:• Impounding reservoirs in the Waitakere and HunuaRanges.• All other asset types such as pumping stations andtreatment plants.• The local distribution systems.Many of our existing water supply assets will needupgrading to:• Meet more stringent New Zealand Drinking WaterStandards.• Provide for growth• Provide greater security of supplyOne example is the need to provide additional pipelinecapacity from the Redoubt Road Reservoir to centralAuckland.Key watersupply assetswe need tolook after anduse to ouradvantageRefer to Watercare AssetManagement Plan 2008Watercare trunk treated water mains’ length distribution by year built125100Cast IronPVCMajor replacement programme needed from 2027 onwards.Concrete lined steelAsbestos Cement75Length(km)502501900-19101911-1920 1921-1930 1931-1940 1941-1950 1951-1960 1961-1970 1971-1980 1981-1990 1991-2000 2001-2010Decade Pipes Built17Final 2008 Strategic Plan – December 2008

Key assets weneed to lookafter and use toour advantage.Maintaining ourcurrent services– lookingforwardWatercare trunkwastewater pipesreplacementestimated at $2.3Bbetween 2027and 2100Asset management plansgenerally look forward 20 yearsbut this Strategic Plan has a100 year horizon and indicatesthat significant investment formaintaining networks will beneeded in addition to that requiredto meet population growth.• Between 2027 and 2100 trunk water pipes replacementestimated at $2.4billion and trunk wastewater at2.3billion (Watercare only)• For trunk water pipes the replacement profile continuesto increase from now through to a forecast peak in theperiod 2040 to 2060. At this time an estimated 110kilometres of pipe will need to be replaced every decade.• For Watercare’s trunk wastewater network the oldest ofthe sewers were built immediately after the First WorldWar. The capacity of that system has in many casesbeen exceeded as designers at that time looked to meetthe future population forecast for the 1950s or 1960s.The lack of capacity today in that part of the system is akey driver for wastewater investment.• The 1950s and 1960s saw expansion of the wastewatersystem to convey wastewater to the Mangere WWTP.Those systems are likely to require replacement in thedecade 2040 to 2050 and beyond, broadly at the sametime as the peak of water pipe replacement.• The value of Watercare’s trunk water and wastewaterpipe systems today is $672 million (Watercare 2008Annual Report).• The value of North Shore’s trunk wastewater pipesystems today is $50 million.• When originally installed, many of these pipe systemswould have been in less built up areas. By the middleof the 21st century the majority will be in built upurban environments. Replacement of pipe networks willpresent many challenges including:– Maintaining the levels of service while taking parts ofthe network out of commission;– Availability of pipeline materials in New Zealand;– Cost of works and spreading the effect on prices tocustomers; and.– Inconvenience to others when pipelines have to beexcavated as many are in transport corridors.These figures exclude all local system costs.Watecare Trunk Pipeline Replacement ProfileLengths of trunk pipeline (water & wastewater) forecast for renewal in 10 year periodsLocal waterand wastewatersystems will alsorequire substantialrenewal costs180160140120WaterWastewater10080Length(km)604020Keywastewaterassetsrequiringprotection02001-20102011-2020 2021-2030 2031-2040 2041-2050 2051-2060 2061-2070 2071-2080 2081-2090 2091-2100 2101-2110DecadeMangere Wastewater Treatment Plant (WWTP) in theSouth West of the region.Rosedale Wastewater Treatment Plant (WWTP) in theNorth East of the region.18North Shore City has trunk wastewater assets that will need replacement in similar time frames.Final 2008 Strategic Plan – December 2008

Future climate change isconsidered in this 100 yearstrategic plan as effects couldinfluence in particular:• sources of water for supply;• the behaviours of consumers; and• the drainage networks.Natural variations will continue to affect the NewZealand climate in future, along with long term climatechange trends. These variations, such as the El Nino andInterdecadal Pacific oscillations, may act to suppress orenhance the effects of climate change over periods of twoor three decades.Scenarios for Auckland region published by theMinistry for the Environment in 2004 suggestedvariations in rainfall of between -6% and +2%over the annual average precipitation.Reviewing the past ten years of rainfall indicatesthat annual rainfall totals for Auckland have variedby -21% and + 25% of the average.During this period the region has been able tomeet demand despite these variations and duringthe most serious drought on record.This suggests that the water sources are robustenough to cope with the suggested variations inthe future climate, subject to proving additionalcapacity to meet future demand.Planningfor climatechange1,600Actual Annual Rainfall Totals(millimetres per annum)= Actual Annual Rainfall Totals(Owairaka Station, NIWA)1,4001,2001,000Rainfall perAnnum(mm)800600400200Climate Change Annual Rainfall Range Average Projected MaximumClimate Change Annual Rainfall Range Average Projected Minimum095-96 96-9797-98 98-99 99-00 00-01 01-02 02-03 03-04 04-05YearsThere is a strong relationship between air temperatureand demand for water. The Ministry for the Environmentscenario suggests annual average air temperature variationof between 0.6ºC and 1.3 ºC between 1990s and 2030 and0.6 ºC and 3.8 ºC between 1990s and 2080s. The regionaltreatment and distribution facilities are designed for peakdemands during the hottest part of the year.Recorded short, sharp daily variations exceed thoseprojected as a result of climate change and are moreimportant than annual average temperatures. Patternsof demand will continue to be monitored to ensureappropriate plans are put in place when climate signalsare clear.Wastewater and stormwater networks will be affected byincreased peak flows. Work undertaken by North ShoreCity Council suggests a wet weather wastewater overflowoccurring once a year at present could occur twice asoften in the future.Wastewater treatment plants are built to handle thesudden increase to inflows caused by heavy rain. Thepotential effects of changes in rainfall intensity will betaken into account when detailed upgrading optionsare considered.The most recent publication of findings by theInternational Panel on Climate Change provides a greaterdegree of certainty around the possible effects. SpecificAuckland based scenarios will be considered for the effectof extreme events, recognising that short term climate islikely to be a greater driver than long term changes.Climatechange willaffect all ofus and wemust planfor it19Final 2008 Strategic Plan – December 2008

A regionalbiosolidsmanagementstrategy thatencouragesbeneficial useis requiredMajorbeneficial useof biosolidsis proposedsubject toResourceConsentsNationally and internationally; there is recognition thatbiosolids can be used beneficially rather than being sentas waste to commercial landfills. Beneficial uses includesoil conditioning, land rehabilitation or use as a fertilizer.Currently, the region does not have readily availablemarkets for the beneficial uses of biosolids.Regionally, the two largest wastewater treatment plants atMangere and Rosedale produce 300 tonnes per day and 30tonnes per day of biosolids respectively.Action to address the regionalmanagement of biosolidsWatercare has entered into an agreement with the KelliherCharitable Trust that will see quarried parts of PuketutuIsland rehabilitated with treated biosolids from theMangere Wastewater Treatment Plant, subject to resourceconsent processes. Puketutu Island is in the ManukauHarbour adjacent to the Mangere WastewaterTreatment Plant.Mangere produces a high quality biosolids product whichis safe to use for soil conditioning and land rehabilitation.Permits for the proposal will be sought from both theAuckland Regional Council and the Manukau City Councilin 2008. The rehabilitation proposal includes a biosolidsimpoundment covering the quarry site with a void space ofaround 4,000,000 m 3 for biosolids. This will cater for ourbiosolids needs for more than 35 years.Subject to successfully gaining permits for this sustainableuse of biosolids, Puketutu Island will be ultimately usedas a regional park. The regional park will be in publicownership.Other work on beneficial uses of biosolids is also beingundertaken to compliment the Puketutu Island scheme.North Shore City council and Watercare continue toexplore new opportunities, for example application toforest.The ThreeWatersStrategicPlan is wellaligned withthe AucklandSustainabilityFramework20Alignment with the AucklandSustainability FrameworkThis Three Waters Strategic Plan is well aligned with thethinking and outcomes of the Auckland SustainabilityFramework. Through its eight ‘goals’ and eight ‘shifts’ theFramework is aimed at improving the regions forwardplanning processes so that it can better respond to futurechanges and opportunities. This aim has been echoedthrough the Three Waters Programme over the past fouryears, through the regionally supported Steering Groups,regular working groups and publication of the many jointregional planning publications.The Auckland Sustainability Framework confirms that overthe Three Waters Planning Period, the Auckland regionwill face significant changes from global forces such aspopulation growth and climate change.The concept of sustainability is at the heart of theAuckland Sustainability Framework and the Three WatersStrategic Planning Programme, with both initiativeshaving a key focus on developing a resilient region withrobust ecological systems supported by the provision ofinfrastructure that has flexibility built in for the future.Final 2008 Strategic Plan – December 2008

Part CIntegratingthe delivery ofThreeWatersServices21Final 2008 Strategic Plan – December 2008

Maximisingefficiency byintegrateddelivery ofthree watersservicesWhere weare nowDeciding ourfuture needsExisting urbanwater supplyInfrastructureEstablish futureneedsLevels of service(Urban and rural)Managing ourwater demandWastewater useStormwater useExisting urbanwastewaterinfrastructureEstablish futureNeedsLevels of service(Urban and rural)Flow reductionopportunitiesBeneficial usePotentialExisting urbanstormwaterinfrastructureEstablish futureNeedsLocal solutions forflood control andstream managementRegional approach tocontaminant controlat sourceBeneficial use policyIdentifyingour optionsInvestigateOptionsDemand reductionNew sourcesRegionalinfrastructureneedsPolicyInvestigateOptionsOn site solutions/local treatmentRegionalinfrastructureneedsCommunity anddischarge locationsInvestigateOptionsFocussed on policySediment controlContaminant controlBeneficial useDesign standardsPolicyEvaluatingOptionsOptimisation, Scenario Analysis, Multi Criteria AnalysisImplementing Mix of solutions to best meet needs – appropriate design standards, lowimpact design, on site and local solutions and regional infrastructureIntegrated policy, design and deliveryWe havechoices- thecommunitymust decidewhat it iswilling toacceptIn the short term, an immediately available option forintegrating three waters delivery is the use of rainwatercollected on site as a source of non-potable water.This can be used in both greenfield development sitesand in brownfield development sites, particularly asredevelopment occurs. The cost of using rainwater ishigher than many alternatives but may still be an option ofchoice for some members of the community. Its use canhave other benefits in relation to stormwater management.Low impact design, control of contaminants at sourceand local use of treated wastewater as a source of nonpotable water should be encouraged within a consistentregional policy framework. This needs to be developedcooperatively by regional and local councils and networkoperators to take into account overall costs and benefits.This work is currently underway.Use of treated wastewater as a direct substitute forpotable water is technically feasible. This will requireconsultation and strong community and Ministry of Healthsupport. Direct use of treated wastewater for drinking isnot included as a part of the current Strategic Plan.Worldwide trends include:• Integration with community outcomes.• Restoring the water cycle.• Protecting and enhancing ecosystems.• Recycle, reduce and reuse.The Auckland community must decide which of the aboveit is willing to accept.Water demand management must be actively promoted, ifwe are to defer the need for new water sources.22Use of treated wastewater for industrial purposes isviable and the extent of use will depend on relative costscompared to the cost of potable water.Final 2008 Strategic Plan – December 2008

Central GovernmentLegislationLocal Government ActResource Management ActBuilding ActPublic Works ActOther PolicyWithin anintegratedstatutoryand planningframeworkAuckland Regional CouncilRegional Policy StatementAuckland Sustainability FrameworkRegional PlansThree WatersVisionThree WatersIssues ReportThree WatersStrategy DiscussionDocument*Three WatersStrategic Plan 2008Master PlansImplementationPlans and Updates**Policy Direction,Justification,Plan Changes andImplementationThree WatersStrategicPlanningProgrammeSponsored and leadby WatercareInfrastructureIdentification,Design,Consenting andImplementationDistrict and BusinessPlanning PolicyAuckland CityFranklin DistrictManukau CityManukau WaterMetrowaterNorth Shore CityPapakura DistrictRodney DistrictUnited WaterWaitakere CityWatercareOn-goingMonitoring,Review,Reporting andModificationsManyorganisationshave a roleto play indeliveringThree WatersServices* Produced as a draft discussion document with no formal feedback request.** Work already commenced.Water demand management will be a critical requirementfor the successful delivery of efficient three waters services.This is discussed in Part E.23Final 2008 Strategic Plan – December 2008

Integratedplanning ina broadercontextThe delivery of three watersservices is inextricably linkedto land use planning, which isundertaken by regional and districtcouncils and, consequently, isoutside the control of networkoperators. The Three WatersStrategic Planning Programme isbeing undertaken to reflect:• Current land use and development areas as defined inregional and district planning documents, in particular,the Regional Growth Strategy;• Possible areas outside the current Metropolitan UrbanLimits that could be developed in the future; and• Projected population growth to 2100 that will affectfuture land use patterns.The Three Waters Strategic Planwas prepared to service the needsof the community in accordancewith known requirements and torespond to changing future needs,not to constrain growth by limitingaccess to three waters services.The methods and actions that will be taken to ensureintegrated delivery of three waters services are describedin the following chart.GoalMethodJoint action by Watercare and LocalNetwork OperatorsProviding forGrowthRegional StrategicPlanningParticipate in Regional SustainabilityFramework ProcessNational PolicyDevelopmentLobby Central Government on MattersRelating to Three WatersMeetingRegulatoryRequirementsRegional PolicyDevelopmentParticipate in Regional Policy and PlanProcesses Relating to Three WatersDistrict Plan PolicyDevelopmentContribute to District Plan Policy DevelopmentRelating to Three WatersIntegrated,coordinatedactions arerequired onan on-goingbasisThreeWatersStrategicPlanningProgrammeAgreeing Levelsof ServiceDelivery ofIntegrated ThreeWaters ServicesLocal Government ActProcessesConsumer LiaisonProgrammesSeamless Efficient Deliveryof ServicesRegional ConsistencyLinked Provision ofServicesSustainable Delivery ofServicesProvide Input to Long TermCouncil Community PlansCustomer Surveys andConsultation ProgrammesJoint Planning of Trunk andLocal NetworksDevelopment of Regional InfrastructureDesign Standards ManualsPotable Water Substitution by Stormwater andTreated Wastewater to Appropriate ExtentBalanced Consideration of Social, Cultural,Environmental and Economic Well-beingsOptimised Maintenanaceand Operating ProgramesDevelopment of Regional Infrastructure ManualsThree Waters StrategicPlanDevelopment of Regional Implementation Plans24Final 2008 Strategic Plan – December 2008

Part DWastewater25Final 2008 Strategic Plan – December 2008

Wastewater- our currentsituationThe Mangere Wastewater Treatment Plant is a state ofthe art facility which treats flows from Auckland City,Manukau City, Papakura District and Waitakere CityThe Rosedale Wastewater Treatment Plant is a state of theart facility which treats flows from North Shore CityWastewater Treatment and Discharge FacilitiesExisting North Eastern (Rosedale) WWTP2010 long sea outfall discharge from Rosedale WWTPExisting South Western (Mangere) WWTPExisting Shoreline discharge from Mangere WWTPManywastewaterissuesneed to beaddressed nowand in thefuture.Indicative Wastewater Network IssuesExisting combined sewer area, area with main wastewater wet weather overflows and areawith dry and wet weather capacity constraintsExisting areas of known higher and/or moderate infiltration and inflowWatercare trunk sewers with capacity constraints in the short to medium termCritical Watercare trunk sewers which cannot be accessed for maintenance purposesCentral Auckland area where wastewater capacityupgrades are needed most and which are furthest fromexisting treatment plantsLike many of our large trunk sewers, the Hobson Baypipeline is nearing the end of its life and is being replacedto provide more capacity26Final 2008 Strategic Plan – December 2008

Average projected daily wastewater flows as m 3 /d* (indicative)* Based on 300 litres per person per day, which includes allowances for domestic, industrial and commercial use andgroundwater and surface water inflow.City or District 2006 2016 2046 2076 2100Auckland 120,000 150,000 200,000 270,000 325,000Manukau 90,000 115,000 150,000 210,000 255,000North Shore 60,000 75,000 90,000 120,000 150,000Wastewater– some factsand figures– presentand futurePapakura 12,000 15,000 20,000 25,000 30,000Waitakere 55,000 70,000 90,000 120,000 150,000Main Watercare trunk sewer capacitySewer Name Areas Served Issue Action RequiredWesternInterceptorWCC and 4000haof ACC and parts ofMCCCapacity upgraderequired before 2050Concourse storagerequired in Waitakere City by2012Manukau Siphon As above Inaccessible formaintenanceRequires duplication to allowaccess (priority)HillsboroughTunnelCentral AucklandInaccessible formaintenanceRequires duplication to allowaccess (priority)Orakei Main Sewer Central Auckland At wet weathercapacity**Capacity augmentationEastern InterceptorCentral Auckland,MCCAt wet weathercapacity**Capacity upgrade, including newHobson Bay Tunnel(under construction)SouthernInterceptorSouth WesternInterceptorMCC, PapakuraDistrictAs aboveUpper section requiresduplication by 2015**Middle sectionrequires duplicationby 2030**(Note : This does not include North Shore trunk sewer constraints or local network constraints).WWTPCurrentAverageDaily FlowTreatment CapacityCurrentlyConsentedMaximumPossibleMaximumat ExistingLocationDuplicationPossible DuplicationExisting wastewater treatment plant capacities m 3 /dMangere 300,000 390,000 >750,000*** 450,000,subject toconfirmationDisposal CapacityMaximum atAlternative Locationin General Locality>600,000*Papakura Channel)> 750,000(South Tasman Sea)Existingtreatmentplants havepotential totreat muchgreaterpopulationsthan atpresentRosedale 65,000* 90,000* > 450,000*** >450,000,subject toconfirmationNot assessed27* As meaning above ** Upgrades required to meet regional overflow targets *** Some upgrading would be required.Strategic Plan – Confidential – Discussion Draft, Version 1 June 2007

A Wastewater vision we– Learning can allfromsharethepastA list of approveddemandmanagement toolsSome ways of dealing withwaste that were successfulin the past can no longerbe used in Auckland urbanareas because of theireffects on public health andthe environment….It is no longer acceptable to the people of Auckland to have:Sanctioned discharges of untreatedor poorly treated wastewaterto waterUnlimited wastewater overflowsUnpleasant odours from any part ofwastewater systemsSimple, localproblems canhave majorcumulativeeffectsPractical experience shows:Gulley traps can allow large volumes of stormwater intowastewater networksPrivate household sewers are a major source of excessflows into public sewers and it is not practicable toprovide a water-tight systemIf flows in pipes get too low, like during the 1994drought, problems with solids settling occursIt is not possible to prevent all overflows occurring28Final 2008 Strategic Plan – December 2008

Question Answer Influencing factorsWhat effect will waterdemand management haveon future wastewatermanagement needs?Will on-site wastewatersystems be used to avoid orreduce the need for majorinfrastructure upgrading inexisting urban areas?No significant effect for theforeseeable future, but could infuture if alternative householdwastewater systems used, suchas vacuum systems or grinderpumps. Care required to avoidinsufficient flow to keep solidsmoving along pipes.On-site systems will not form asignificant part of the solutionfor existing urban areas.Major upgrades are requiredto address existing issues.Any use of on-site systemsin existing urban areas wouldhave negligible, if any, effectson trunk wastewater upgradingrequirements.Demand management could reducedry weather wastewater flows.These have no significant effect onpipe sizes (designed for peak wetweather flows) or treatment plantsize (design mainly affected byload from number of people servednot dry weather flow).On site systems are notsuitable for use in most partsof urban Auckland becauseof high population density,low permeability soils andrisks to public health and theenvironment.Approach used inThree Waters PlanningWater demand management willbe promoted for water supplyreasons, not wastewater. This canbe reviewed depending on levelsof water savings achieved in thefutureUse of on-site systems will befacilitated for use in appropriatecircumstances in greenfielddevelopments.Wastewater– questionsand answersfor the future- flexibility ofsolutions willbe keyWill local wastewatertreatment systems be usedto avoid or reduce the needfor major infrastructureupgrading in existing urbanareas?Local wastewater treatmentsystems will not form asignificant part of the solutionfor existing urban areas. Theyare generally unsuitable for usein major urban areas, exceptwhere safe use or disposalmethods exist.Safe disposal methods do notgenerally exist in most parts ofurban Auckland, as most soils arelow permeability and dischargeto streams would require highcosttreatment that would notrepresent the Best PracticableOption. Where a defined use fortreated wastewater exists, localplants can be built later but thiswill not change initial upgradingneeds.Once a preferred regionalsolution has been agreed, asensitivity analysis will beundertaken to assess if localtreatment could reducelonger-term infrastructurecapacity needs.This will include testing optionsof greater numbers of treatmentplants.Is it intended to use treatedwastewater for non-drinkingpurposes?Limited quantities of treatedwastewater are currentlyused for non-drinkingpurposes at the Mangereand Rosedale TreatmentPlants. Uses for industrialpurposes and irrigation havebeen investigated in the pastbut costs and other factorsprevented such use. Safeuse for irrigation and otherpurposes will continue to beinvestigated and promoted,as appropriate.Community acceptability, theprotection of health and safetyand economics will be themain factors that influencethe extent of future use oftreated wastewater. The cost ofusing treated wastewater hashistorically been greater thanusing piped water. As long asthat remains the case, it will be amajor barrier to its use.The potential to use up to 5,000m 3 /d for industrial cooling waterhas been identified as part ofthe three waters programmeand is being pursued. Otheropportunities will be investigatedat least every five years.Is it intended to use treatedwastewater for drinking?Not at present, but it remainsan option for the future.The same factors as above willinfluence decisions. It is notexpected to be the community’sfirst choice while alternativewater sources can be developed,particularly at lower cost.Does not form part ofcurrent strategy.How will greenfielddevelopments be servicedfor wastewater?It is expected that areas withinthe existing Metropolitan UrbanLimit will be connected to theexisting wastewater systems.Each development outside theexisting MUL will be consideredon its merits. Any one or moreof on-site systems, satelliteplants with local use or disposaland connection to the mainurban wastewater system willbe considered.Regardless of which solutionis used in any particular case,either inside or outside the MUL,it will be important for long termsustainability that the use ofappropriate design standards areenforced.New policies to ensure theinfluencing factors listed left areproperly addressed willbe pursued.How can existing public andprivate drainage systems bebetter utilised to deal withfuture growthFinal 2008 Strategic Plan – December 2008Key to better utilisation of thedrainage systems will be usingthe capacity of that drainagesystem as it was originallyintended - specifically thismeans reducing stormwaterinflows.Infiltration/inflow control canreduce the levels of flowsrequired to be conveyed by thedrainage system. Also possibleuse of low pressure or vacuumsystems could reduce wastewaterdemands.Due to the variability of resultsand cost of reducing inflow andinfiltration, it has only beenconsidered at a high level atthis time (will be considered inmore detail later). As the specificcity implementation plans aredeveloped, greater certaintycan be placed on the results ofinflow/infiltration improvementsand assessed through anopitimsation process.29

FutureRegionalWastewaterOptionsAny future option must includetreatment facilities and a safemeans of using or dischargingtreated wastewater back to theenvironment. Six potentiallysuitable regional treatment plantsites were identified, including thecurrently unused site at Drury.Any future South Eastern or Southern WastewaterTreatment Plant is not expected to be required until thesecond half of the planning period, so was not evaluatedin detail.RodneyDistrictExisting NorthEastern(Rosedale) WWTPPossible futureNorth Western(Taupaki) WWTPNorthShore CityIt is almostcertain thatcontinueddischargeof treatedwastewaterto water willbe requiredfor theforeseeablefutureWaitakereCityExisting SouthWestern (Mangere)WWTPAucklandCityPossible FutureSouthern WWTPPossible FutureCentral WWTP(Site to bedetermined)ManukauCityPapakuraDistrictPossible FutureSouth Eastern WWTP(Site to be determined)FranklinDistrictMore than 99% of treated wastewater is currently discharged direct to the environment. Unless there is amajor financial or other interventions to bring about change, this figure is unlikely to drop below 95% withinthe first half of the 100-year planning period.In 2006 , Three Waters Report 24 - Interim TrunkWastewater Master Plan - Concept Development andInitial Assesment was completed. This report identified awide range of options for addressing the region’s trunkwastewater issues for the next 50 years. Through thisprocess a number of concept solutions was assessed.Options which included a significant component of flowunder gravity to a treatment plant were shown as morepreferable compared to pumped options.Other relevant reports include:TW 38 - Distributed Wastewater Treatment Plants.TW 40 - Evaluation of complete wastewater collection,treatment and use/disposal options.TW 46 - Complete Wastewater Options30Final 2008 Strategic Plan – December 2008

RodneyDistrictNorthShore CityPossibleFuture NorthEasternRegionalWastewaterTreatmentPlant ConceptWaitakereCityAucklandCityManukauCityPapakuraDistrictFranklinDistrictAreas which could be served shown in blue.Treatment PlantDischargeCurrent Status Existing. New 2.8 km outfall due for completion byDecember 2010.Legal OwnerNorth Shore City Council.Consent Status Designated site. 6 m 3 /s authorised to 2030 (based on North Shorepopulation of 300,000 people).Potentially availablecapacity(Average daily flow in m 3 /d)Potential equivalentpopulation servedPossible catchmentareas servedTechnical feasibilityMore than 450,000. More than 450,000.1,500,000 1,500,000North Shore City, Waitakere City and parts of central Auckland.No issues of particular concernapparent from preliminaryinvestigations.Will be existing by time regional facilityestablished but could require some upgrading forlonger-term regional use.An existingWWTP withpotential forexpansion31Final 2008 Strategic Plan – December 2008

PossibleFuture NorthWesternRegionalWastewaterTreatmentPlant ConceptRodneyDistrictNorthShore CityWaitakereCityAucklandCityManukauCityPapakuraDistrictFranklinDistrictAreas which could be served shown in blue.A possiblefuture WWTPsite at a siteowned byWatercare(other sitescould also besuitable)Treatment Plant Discharge - East Discharge - WestCurrent Status Greenfields site. New 2.8 km tunneland outfall due forcompletion by December2010.Concept.Legal Owner Watercare. North Shore City. Not yet existing.Consent Status Land zoned rural. 6 m 3 /s authorised to2030.Potentially availablecapacity(Average daily flow in m 3 /d)Potential equivalentpopulation servedPossible catchmentareas servedTechnical feasibilityNo consents applied for.More than 300,000. More than 450,000. More than 300,000.1,000,000 1,500,000 1,000,000Waitakere City and partsof central Auckland.No issues of particularconcern apparent,based on preliminaryinvestigations.North Shore City,Waitakere City and partsof central Auckland.Will be existing bytime regional facilityestablished.Waitakere City and partsof central Auckland.High energy coastwill require carefulengineering, but feasible.32Final 2008 Strategic Plan – December 2008

RodneyDistrictNorthShore CityPossibleFuture CentralRegionalWastewaterTreatmentPlant ConceptWaitakereCityAucklandCityManukauCityPapakuraDistrictFranklinDistrictAreas which could be served shown in blue.Treatment PlantDischargeCurrent Status No suitable site yet identified. Concept only.Legal OwnerNot yet existing.Consent Status No consents applied for. No consents applied for.Potentially available capacity(Average daily flow in m 3 /d)Around 150,000 subject toconfirmation.Around 150,000 subject toconfirmation.Equivalent population served 500,000 500,000Possible catchmentareas servedTechnical feasibilityHighly complex treatmentplant with undergroundconstruction.Parts of central Auckland.Up to 5 km long land basedstorage tunnel in CBD and 2km outfall, but expected to befeasible.A possibletheoreticalfuture WWTPsite for whichno actual sitehas yet beenidentified33Final 2008 Strategic Plan – December 2008

PossibleFuture SouthWesternRegionalWastewaterTreatmentPlant ConceptRodneyDistrictNorthShore CityWaitakereCityAucklandCityManukauCityPapakuraDistrictFranklinDistrictAreas which could be served shown in blue.An existingWWTP sitewith potentialfor expansionTreatment PlantShorelineDischargePapakura ChannelTasman Sea SouthCurrent Status Existing. Existing. Concept. Concept.Legal Owner Watercare. Watercare. Not yet existing. Not yet existing.Consent Status Designated site. 25 m 3 /sauthorised to 2032.No consentsapplied for.No consentsapplied for.Potentiallyavailable capacity(Average daily flow inm 3 /d)More than 750,000. Around 500,000but subject toconfirmation.Expected to bemore than 600,000but subject toconfirmation.More than 750,000.Equivalentpopulation served2,500,000 1,500,000Possibly more2,000,000 2,500,000Possible catchmentareas servedAll areas of MUL,excluding NorthShore city.Manukau City,Papakura Districtand parts ofAuckland City.Manukau City,Papakura Districtand Auckland City.All areas of MUL,excluding NorthShore City.34TechnicalfeasibilityNo issues ofparticular concernapparent exceptnitrogen removaland pathogenremoval undersome peak flowconditions.Existing.Feasible butinvolves work insensitive marineenvironment.40km long pipeline.Work in sensitivemarine environmentand high energycoast will requirecareful engineering,but feasible.Final 2008 Strategic Plan – December 2008

Choosing between optionsTwo sets of decisions need to be made:• How do we address the immediate need to provideadditional sewer capacity to serve central Auckland?• Where do we treat and discharge treated wastewater inthe future?In making these decisions, there are a number ofimportant outcomes we want to achieve:• To maximise gravity flow of wastewater from where itis generated to the treatment plant as far as possible, toreduce energy use.• To maximise the use of investment in existing plants, todefer the need for further expenditure on new plants foras long as possible.• To retain as much flexibility as possible for the future.• To minimise risks of delay as a result of land acquisitionand resource consent requirements.• To minimise existing risks associated with major trunksewers that are inaccessible for maintenance purposes.• To ensure solutions are technically feasible and have anappropriate balance of social, cultural, environmentaland economic well-beings.The initial decision needs to be based on a pragmaticassessment of all key factors. The second decision, relatingto longer term strategic directions for wastewater, needsto be based on a comprehensive assessment of optionsand the use of multi criteria assessment techniques.Choosingwherewastewatergoes initially -Factors to beconsideredNorth EastNorth WestForSite owned by WatercareAgainstPlant does not existNo consentsCould add 10 Yearsbefore startMajor pumping (unless existingsite changed)Extra peak flow treatmentDifficult tunnel constructionLarger outfallCost > $2,000 per person servedNWNEHubCForExisting consented sitePotential long term capacity for 1.5million peopleCost < $1,500 per person servedAgainstMajor pumpingPeak flow treatment restrictionsPeak flow discharge restrictionsNew consent required if out of districtsewage included, possible variation onlyDeep tunnel constructionCompeting land use interestsSouth WestForExisting consented siteFlow okay to 2027Load okay to 2046 at shoreline withextra hydraulic and nitrogen removalcapacityPeak flow capacityMaximises gravity flowsMaximises benefits of existinginvestmentMaintains maximum flexibilityMajor reduction of risks associatedwith maintaining existing trunksewersCost around $1,000 per person servedSWCentralForClose to location to whichwastewater can gravitateAgainstNo site identifiedSite may not existNo discharge location identifiedNo consentsSerious peak flow restrictionsBiosolids restrictionsCould take 15 years before startCost > $3,500 per person servedKeyrequirementsMaximise• gravity flow• current investment• flexibility• sustainabilityMinimise• cost• riskAgainstConsent variation neededNeed to relocate outfall by 2027 orlater or divert flow to another plantTidal discharge35Final 2008 Strategic Plan – December 2008

Providingmaximumflexibilityto meetchangingcircumstancesNeither a Central nor a North Western WWTP offerfeasible short term options to address the region’simmediate needs for the reasons given on the previouspage. In particular, neither has an identified dischargelocation, no site for a Central WWTP is easily identifiableand none of the treatment plant or discharge locations hasresource consents.Of the remaining two options, use of the existing SouthWestern (Mangere) WWTP up to it’s consented dischargeProposed concept:Duplicate the Manukau Siphon andHillsborough Tunnel to allow access formaintenance purposesExtend central interceptor to centralAucklandMaximise gravity flow to South WesternWWTP to reduce energy requirementsCollect more than 70% of Watercare’swet weather overflowsProvide “Hub” at limit of gravity flowarea to pump flows from lower areas tostart of gravity line.Continue using South Western WWTP upto nitrogen and pathogen load limits setout in resource consent conditions forexisting discharge location to maximisebenefits of existing investment.Retain flexibility to change dischargelocation or divert some flows from theHub to a different WWTP.Existing WesternInterceptorload capacity has substantial advantages in terms ofmeeting the desired outcomes listed on the previous pageand is also the least cost option by a substantial margin.Therefore, continued use of the South Western Plant asthe main regional WWTP in the 15 to 20 year time horizonis proposed, providing the advantages described below.New ConcourseStorage TankNew Central InterceptorTransmission SectionExisting PS25New Central InterceptorStorage SectionPS 25 = Major Existing Pumping StationNew CentralStorage TunnelNew HubPumping StationSouth WesternWWTPFirst decision:SouthWestern Plantwill continueas the mainregionalfacility forthe next 15 to20 yearsFlexibility will exist to:Improve treatment plant efficiency atthe South Western WWTP.Relocate discharge to the PapakuraChannel.Relocate discharge to the Tasman SeaSouth.Reduce flows to the South WesternWWTP by using “distributed”wastewater treatment at local level.Divert flows from up to one millionpeople to the North Eastern WWTP.Divert flows from up to one millionpeople to the North Western WWTP.Divert flows from up to 500,000 peopleto a Central WWTP.Beneficially use the high quality treatedwastewater.PossibleNorth WesternWWTPPossible Alternative PapakuraChannel DischargeHubExistingNorth EasternWWTPPossibleCentralWWTPExistingSouth WesternWWTPPossible AlternativeTasman SeaSouth Discharge36Hub = Possible Future Major Pumping StationFinal 2008 Strategic Plan – December 2008

The following process was and continues to be followed to identify a preferred long-term solution.ConfirmWastewaterIssuesIdentify OptionsPreliminary EliminationProcessRefer Three Waters Technical Report TW 2– “Issues Report”, June 2006.• Previous investigations.• New and developing technologies.• Workshops(Refer TW 23, 24, 30, 31, 33-38, 40 and 46).Sensitivity of and/or limited assimilative capacity of receivingenvironment in relation to discharge volumes:• Kumeu River.• Kaipara Harbour.• Upper Waitemata Harbour.Assessment oflonger termwastewateroptionsfor areaswithin theMetropolitanUrban LimitRequired Substantially CompletePrepare Long and ShortLists of OptionsInitial Multi CriteriaAnalysis ofShort Listed OptionsReview of Optionsto Confirm PreferredSolutionOptimisation ofPreferred Solution(including a new centralinterceptor from CentralAuckland and Waitakere Cityto the Mangere WastewaterTreatment Plant)Impracticable or currently unavailable:• Discharge to Woodhill Forest (land ownership and cultural issues).• Large scale land application south of existing South WesternWWTP (soil conditions, land uses and multiple ownership).• On-site systems.• Direct use for water supply purposes.Complete Wastewater Options(Refer TW 46).Distributed Treatment Plants(Refer TW 38).See Pages 40-43See Pages 44-50Once a preferred overall solution has been confirmed, optimisation ofthat option will need to be undertaken to ensure the best overallregional outcome taking into account the following:• Optimum pipeline routes.• The most cost effective way of addressing unacceptablelevels of infiltration and inflow to local networks.• The most cost effective methods for managing andupgrading combined sewers.• The extent of storage that should be provided to minimise wet weatheroverflows and reduce peak flows to treatment plants.• The “Best Practicable Option” for wet weather overflow targetsin the region as a whole.• The role of local treatment plants and potential local beneficial use.• The role of on-site treatment and beneficial use,including recycled water pipe systems.• Different population growth scenarios to the one used forstrategic planning purposes.• Identify the right mix between local and trunk improvements• Identify most cost effective mix of rehabilitation, storage and capacity• Alignment of timing and agreement on design parameters.• Optimisation of existing and proposed wastewater treatment plants• International “Best Practice” advice using Principle Engineering AdvisorDetailed list ofThree Waterstechnicalreportsincluded onback insidecoverMajoroptimisationof thepreferredsolutions willbe requiredFinal Review prior todiversion of flow to asecond regional WWTPFinal 2008 Strategic Plan – December 2008Confirm Choice based on then current circumstances37

Preliminaryassessment oflonger termwastewateroptionsfor areaswithin theMetropolitanUrban LimitA robust,comprehensivemulti criteriaoptionsevaluationprocess wasusedThe following analysismethodology was used to compareoptions:Four specialist groups were established to analyse 14short-listed options on the basis of social, cultural andenvironmental well-beings and legal, technical, risk andtiming issues. Each group finalised the goals the groupwould use to score options and then scored each optionagainst each goal as described below.A separate process was used to consider economic wellbeing.In this process, detailed estimates were preparedby the Project Team and internally and externally peerreviewed. Covec Group prepared Net Present Valueanalyses based on the peer reviewed estimates. All optionswere scored against the economic goals by the ProjectTeam and the process peer reviewed by Price WaterhouseCoopers.As a further part of the overall process, two expert groupsprovided specialist input on wastewater treatment andthe effect of treated wastewater discharges on receivingenvironments for each option (refer TW33).The following scoring system was used consistently byall groups as the basis for assessing the extent to whicheach option contributes to the achievement of a goal:+4 Very good+3 Good+2 Moderately good+1 Slightly good0 Neutral-1 Slightly poor-2 Moderately poor-3 Poor-4 Very poorRanking of options was undertaken from 1 to 14 usinga consistent range of methods for all well-beings,including ranking of:a) Total positive scores for each individual treatment plant.b) Total negative scores for each individual treatment plant.c) Total net scores for each individual treatment plant.d) Total positive scores for each individual treatedwastewater discharge.e) Total negative scores for each individual treatedwastewater discharge.f) Total net scores for each individual treated wastewaterdischarge.g) Total positive scores for all treatment plants incombination.h) Total negative scores for all treatment plants incombination.i) Total net scores for all treatment plants in combination.j) Total positive scores for all treated wastewaterdischarges in combination.k) Total negative scores for all treated wastewaterdischarges in combination.l) Total net scores for all treated wastewater dischargesin combination.m) Total positive scores for all treatment plantsand treated wastewater discharges in combination.n) Total negative scores for all treatment plants andtreated wastewater discharges in combination.o) Total net scores for all treatment plants and treatedwastewater discharges in combination.Grading of options was undertaken for each ranking a)to o) generally using the following system:• Ranking 1 to 3 “Good” Grade• Ranking >3 to 6 “Moderately Good” Grade• Ranking >6 to 9 “Neutral” Grade• Ranking >9 to 12 “Moderately Poor” Grade• Ranking >12 “Poor” GradeAn alternative grading method was used as a check whereappropriate. This involved five equal score bands. Anoverall grading was allocated for each option for each ofthe four well-beings and legal, technical, risk and timingissues. This used the best fit average grade from theindividual grades and other appropriate considerations asset out in Three Waters Technical Report TW 40 – “OptionsEvaluation Process”.This approach allows balanced consideration of:• Local and regional interests;• Positive and negative features;• Multiple components in a way that minimises thelikelihood of bias and any individual component undulyinfluencing the outcome disproportionately.Trunk sewers were not considered to any significant extentin the analysis as the main new trunk sewer works arecommon to all options. Any additional overall effectswill be short term and limited in extent, compared to theeffects of discharges, in particular.WeightingIndividual criteria were given at a weighting of 2 and 3while keeping other criteria at a weighting of 1. This didnot result in any significant changes in relative preferencebetween options.38Final 2008 Strategic Plan – December 2008

Option North Eastern WWTP North Western WWTP Central WWTP South Western WWTPAreasServedPeopleServedB2 NSCC 0.5millionC2C1EF2F1G2G1NSCCWCCNSCCWCCPartACC1.0million1.5millionNSCC 0.5millionNSCC 0.5millionH NSCC 0.5millionI NSCC 0.5millionJ1 NSCC 0.5millionK NSCC 0.5millionDischargeLocationNew EastCoastLongOutfallAsaboveAsaboveAsaboveAsaboveAsaboveAsaboveAsaboveAsaboveAreasServedPeopleServedDischargeLocationAreasServedPeopleServedDischargeLocationAreasServedNot used Not used AsexistingNot used Not used Asexisting,lessWCCNot used Not used Asexisting,lessWCC& partACCWCC 0.5millionWCC 0.5millionWCCPartACCWCCPartACC1.0million1.0millionNot usedWCC 0.5millionTasmanSeaNorthNew EastCoastOutfallTasmanSeaNorthNeweastCoastOutfallTasmanSeaNorthPartACCPartACCNot usedNot usedNot usedNot used0.5 million NewWaitemataHarbouroutfall0.5 million NewWaitemataHarbouroutfallAsexisting,lessWCCAsexisting,lessWCCAsexisting,lessWCC &partsACCAsexisting,lessWCC &partsACCAsexisting,lesspartsACCAsexisting,lessWCC &partsACCPeopleServed2.5million2.0million1.5million2.0million2.0million1.5million1.5million2.0million1.5millionDischargeLocationTasmanSeaSouthPapakuraChannelTasmanSeaSouthExistingShorelinePapakuraChannelTasmanSeaSouthPapakuraChannelTasmanSeaSouthExistingShorelineExistingShorelinePapakuraChannelExistingShorelineShort ListedOptionsNotes:• Any option with a letter only indicates the dischargelocation for the South Western WWTP is the existingshoreline discharge to the Manukau Harbour.• Any option with the number 1 after a letter indicatesthe discharge location for the South Western WWTP isa relocated discharge to the Manukau Harbour in thePapakura Channel.• Any option with the number 2 after a letter indicatesthe discharge location for the South Western WWTP is arelocated Tasman Sea South discharge.Option A is generally similar to Option B, but duplicatesexisting trunk sewers instead of a new central interceptor.Option A was eliminated on the grounds of cost andpractical considerations.Option D is generally similar to Option C, except nitrogenand microbiological discharge loads would be up to twicecurrent consent loads. It was not evaluated in detail in thestrategic planning process but can be reconsidered laterif required.All options except Option D are based on meeting existingdischarge nitrogen and microbiological consent loads fromthe North Eastern WWTP.All discharges from the South Western WWTP at theexisting shoreline discharge will meet nitrogen load limitsas existing resource consent conditions or as otherwiseneeded to maintain harbour water quality.Stringent pathogen treatment will be continued for anydischarges from the South Western WWTP at the existingshoreline discharge or any relocated discharge to thePapakura Channel.A wide rangeof short listedoptions wasevaluated39Final 2008 Strategic Plan – December 2008

EvaluatedSchemeOptionsB to KRodneyDistrictWaitakereCityNorthShore CityHubNew LongSea OutfallB2AucklandCityComplete SchemeOption BRodneyDistrictConcourseWaitakereCityPS25NorthShore CityHubNew LongSea OutfallC1, C2D1, D2AucklandCityComplete SchemeOption C & DManukauCityManukauCityC1, D1B2PapapukaDistrictFranklinDistrictC2D2PapapukaDistrictFranklinDistrictRodneyDistrictNorthShore CityNew LongSea OutfallEComplete SchemeOption ERodneyDistrictComplete SchemeNew LongOption FSea OutfallF1, F2NorthShore CityNWWWTPConcourseWaitakereCityPS25HubAucklandCityTasman SeaNorthConcourseWaitakereCityPS25HubAucklandCityEManukauCityManukauCityF1PapapukaDistrictPapapukaDistrictFranklinDistrictF2FranklinDistrictRodneyDistrictNew LongSea OutfallG1, G2Complete SchemeOption GRodneyDistrictComplete Complete Scheme SchemeOptionOptionHHNew LongSea OutfallHKEYPS25- Indicatespipes/routes- PumpingStationConcourse - WaitakereFacilityNWWWTPG2ConcourseWaitakereCityPS25G1NorthShore CityHubAucklandCityPapapukaDistrictManukauCityFranklinDistrictTasman SeaNorthNWWWTPConcourseWaitakereCityPS25NorthShore CityHubHAucklandCityPapapukaDistrictManukauCityFranklinDistrict40Final 2008 Strategic Plan – December 2008

RodneyDistrictRodneyDistrictNWWWTPConcourseWaitakereCityWaitakereCityPS25NorthShore CityNorthShore CityHubJ1HubINew LongSea OutfallIAucklandCityNew LongSea OutfallJ1Central PlantAucklandCityComplete SchemeOption IPapapukaDistrictManukauCityFranklinDistrictComplete SchemeOption JPapapukaDistrictManukauCityFranklinDistrictGoals Relating to SocialWell-Being• To protect public health and safety.• To manage the three waters acitivity so that the use,development, and protection of land can occur in a way,or at a rate, which enables people and communitiesto provide for their social, economic, and culturalwellbeing.• To enhance lifestyle, amenity and recreationopportunities.• To equitably distribute benefits and dis-benefitsbetween existing communities across the region.• To equitably distribute benefits and dis-benefitsbetween present and future generations.• To gain community acceptance.Goals Relating to CulturalWell-Being• To maintain and enhance the mauri of water.• To protect taonga and wahi tapu.• To protect ancestral lands and water.• To protect and enhance the four well-beings of tangata.Goals Relating to EnvironmentalWell-Being• To minimise adverse effects on surface water.• To minimise adverse effects on groundwater.• To minimise adverse effects on terrestrial ecology.• To minimise adverse effects on land and soil.• To minimise adverse effects on rare or sensitiveenvironments.• To minimise adverse effects of construction.• To minimise effects on different habitats and receivingenvironments.• To minimise use of energy and chemicals.• To maximise environmental benefits.Basis of multicriteria usedto AssessOptionsTasman SeaRodneyDistrictNWWWTPConcourseWaitakereCityPS25NorthShore CityHubNew LongSea OutfallKKCentral PlantAucklandCityComplete SchemeOption KPapapukaDistrictManukauCityFranklinDistrictGoals Relating to EconomicWell-Being• To minimise capital costs.• To minimise operating costs.• To minimise whole of life costs.• To minimise funding gaps between project costs andrevenue currently projected to be available.• To be affordable to the community.• To be within the community’s willingness to pay.Goals Relating to Legal, Technical,Risk and Timing Issues• Ability to obtain and comply with resource consents.• Ease of construction.• Technical feasibility and ease of operation.• Flexibility and ability to meet changing circumstancesand community needs.• Potential for new technologies to contribute to thefuture delivery of a three waters service.• Extent of integration with other regional initiatives.• Ability to acquire necessary land access rights.• Time for implementation.• Risk due to climate change.• Extent to which significant existing risks reduced.• Numbers of parties involved in decision making.Options wereevaluated tosatisfy LocalGovernmentAct fourwell-beingrequirements41Final 2008 Strategic Plan – December 2008

Localsolutions willbe used whereappropriateIndicative totalestimatedcapital costof options$M to2100B2 3476C1 3463C2 3511D1 3403D2 3451E 3404F1 3484F2 3532G1 3520G2 3568H 3318I 3445J1 3617K 3867The assessment of longer-termwastewater options within theMetropolitan Urban Limit , based onthe multi-criteria analysis processsummarised on previous pages, enabledthe following preliminary conclusions tobe drawn:• Estimated whole of life costs for all options were within15% of the average and hence were all within thebounds of estimating accuracy. Consequently, wholeof life costs could not be used as a reliable basis fordifferentiating between options.• When options were compared on the basis of scoresfrom the specialist social, cultural and environmentalgroups, Options E, I and K were broadly comparable,followed somewhat further back by Options B2, C2, G1,G2, H, and I. This was confirmed by the numerical scoresin the table, where G (Good) = 1, MG ( Moderately Good)= 2, N (Neutral) = 3, MP (Moderately Poor) = 4 and P(Poor) = 5• Most options were broadly comparable on legal,technical, risk and timing grounds, as all optionsassessed were technically feasible, and the costestimates provided for differences.• If ability to proceed without undue delay were tobecome important, Option E would have advantagesover other options. Option E would also leave greatestflexibility for the future as it would build on existingplants and leave all other future opportunities open.Overall, Option E was considered to be the preferredoption from the multi-criteria analysis but beforemaking final recommendations for strategic planpurposes, further consideration was given to individualcomponents of complete schemes and other factors asset out below.Proposed Role of the Mangere WWTP asPart of the Future Regional WastewaterStrategyContinued use of the Mangere WWTP as the primaryregional wastewater treatment facility is the mostpracticable solution in the medium term for the followingreasons:• It was planned and designed for the purpose;• The Mangere WWTP has existing resource consents toallow treatment of flows under average dry weatherconditions from at least another 300,000 people usingexisting treatment methods;• The Mangere WWTP has the existing ability to treatsubstantially greater volumes of wet weather flows thanthe other major existing WWTP at Rosedale;• The quality of the Manukau Harbour has improvedsubstantially as a result of the major investments madein Mangere WWTP upgrades in the last 10 years;• There is no other facility currently available to acceptregional flows; and• Its continued use in the medium term optimisesthe benefits from historical investments and avoidsthe need for substantial expenditure on additionaltreatment capacity at an alternative site.Medium to Longer-Term Upgradingof the Mangere WWTP as Part of theFuture Regional Wastewater StrategyDecisions on the optimum load that can be treated atthe Mangere WWTP and future upgrading needs will bedetermined under the Resource Management Act. Suchdecisions will be based on the effects of the treatmentplant and associated discharges on the environment.Expert opinion indicates that the two issues that will beof greatest influence in future decision making are theprotection of public health and the effects of nitrogen onthe Manukau Harbour.With the flow balancing effects of the proposed centralinterceptor described below and Project Hobson, asubstantial increase in the WWTP’s ability to treat peakflows will occur. This will result in improved protectionof the public health of harbour users and public healthconsiderations are unlikely to be a constraining factorin the future. This leaves the effects of nitrogen as theprimary limiting factor on Mangere WWTP capacity.Work to date by an expert group of scientists suggeststhat a total nitrogen load to the harbour of three tonnesa day in summer, or possibly less could be needed tomaintain or enhance harbour water quality. The actualacceptable load is likely to be influenced by changes inharbour water quality resulting from improved stormwaterdischarge quality, climate change and naturally occurringchanges in ecology. For internal planning purposes, theimplications of having to meet a total nitrogen load of twotonnes a day in summer by 2050 is under investigation.This compares to nitrogen discharges of around 15 tonnesa day prior to the upgrade.With enhanced biological treatment to remove nitrogen,it is estimated that the required load could be met withthe connected population through to 2050 and possibly2070. Programmes are being developed to refine both theacceptable nitrogen load to the harbour and the level ofnitrogen removal that can be achieved by treatment at theMangere WWTP.If beneficial use of treated wastewater can be successfullyintroduced in the region on a significant scale, a largerload will be able to be treated without increasing thequantity of nitrogen to be discharged to the harbour.Potential to Extend the Capacity ofthe Mangere WWTP by Relocating theExisting Shoreline Discharge Locationfor Treated Wastewater to the PapakuraChannel or to the Tasman SeaExpert advice suggests that a greater population couldbe served by the Mangere WWTP if the existing shorelinedischarge was relocated. Broadly speaking, an additional500,000 people, potentially (compared to the existingdischarge location), could be treated with the dischargerelocated to the Papakura Channel. In excess of 2.5 millionpeople could be treated if the discharge were relocated tothe Tasman Sea.The Tasman Sea option was selected as the preferredoption in the regional wastewater study completed by theARA in 1989. The proposal resulted in such a high level ofcommunity opposition that the decision was overturnedin favour of a treatment plant discharging high quality42Final 2008 Strategic Plan – December 2008

Overall grades from the multi criteria analysis foreach option are shown below for social, cultural andenvironmental criteriaOption B2 C1 C2 D1 D2 E F1 F2 G1 G2 H I J1 KSocial N MP MP MP MP N* N N MG N N N MG MGOutcomes ofPreliminary fourwell-being MultiCriteria AnalysisProcessAchievement of GoalsCultural MG MG MG MP N G MP MP MG MG MG G N MGEnvironmental MG N MG MP MG MG N MG N MG MG MG MP MGIndicative equivalentscores 7 9 8 12 95 to7*10 9 7 7 7 6 9 6* Could vary from moderately good to moderately poor, depending on whether a wider region perspective or a more localperspective is taken.The lower the score, the better the option.treated wastewater at the current shoreline discharge.The Tasman Sea option was reconsidered as part of theThree Waters Strategic Planning Programme. It wouldresult in improved water quality in the Manukau Harbourbut considered inappropriate and/or impracticable for thefollowing reasons:• The solution would require the construction of a tunnelapproximately four metres in diameter and 40 kilometreslong, mainly below the sea, with major construction risksand cost uncertainties;• The asset would be difficult to maintain;• The construction cost, broadly in the order of one billiondollars, could not be staged and would result in a majordrain on scarce community funds;• The expenditure would need to be deferred as longas possible to minimise effects on other regionallysignificant priority projects. There would be a stronglikelihood that short to medium term investments in highquality treatment to allow continued shoreline dischargefrom the Mangere WWTP would be wasted once the newdischarge was commissioned;• To be economically feasible, the discharge would be of agenerally lower quality than any other discharge optionsconsidered in the overall investigation programme andlikely to be strongly opposed by iwi and some othermembers of the community for that reason;• The commitment to such major capital expenditure andthe lower quality treated effluent would compromisethe likelihood that beneficial use of treated wastewaterwould be seriously pursued;The Papakura Channel option was also investigated in thepast, but never seriously promoted. The discharge wouldaffect a relatively pristine part of the Manukau Harbourused for shellfish gathering. Actual effects of nutrients inthe discharge would be difficult to predict with certainty,which would represent a high level of risk.Based on current knowledge, both options would involvean unacceptably high risk of future problems. Neither isconsistent with the philosophy of encouraging maximumbeneficial use of treated wastewater. Both would affectenvironments currently unaffected to any significantextent by wastewater discharges. There is no economicjustification for pursuing either option over and aboveother options.For these reasons, neither option is considered to offer anacceptable means of deferring the need to identify andultimately use a second regional wastewater treatmentplant.Expected Timeframe Before Capacity ofMangere WWTP is reachedThe time by which the capacity of the Mangere WWTP isreached will be determined by the conditions of existingand any future resource consents granted.The average daily flow limits of the existing resourceconsents will be reached in or about 2027 at currentlyprojected population growth rates. While it is anticipatedthat, based on the effective management of effects on theenvironment, new consents will be able to be obtained forincreased flow (but at the same or lower nitrogen dischargeload), this cannot be guaranteed.The range of timeframes by which the capacity of theMangere WWTP could be reached is:a) 2027, if no extension of the existing consent limits canbe obtained;b) Between 2050 and 2070, if new consents can beobtained and new technologies can reduce nitrogenloads sufficiently.Time will be required to obtain consents for any alternativeregional wastewater treatment facility. A decision on asecond regional wastewater treatment plant could berequired no later than 2015 and possibly sooner.South WesternWWTP willcontinue as themain regionalfacility untilit’s capacity isreached43Final 2008 Strategic Plan – December 2008

Ensure shortterm decisionsare consistentwith long termaspirations.Need for Second Regional WastewaterTreatment Plant as Part of the FutureRegional Wastewater StrategyOne of the purposes of the Three Waters Strategic Plan isto set out a long-term strategy for managing wastewaterin the Auckland region in an integrated way with themanagement of water supply and stormwater. Identifyingthe site or sites at which wastewater treatment will beundertaken is one of the fundamental starting points fordeveloping any such wastewater strategy.Important reasons for early identification of the sites atwhich treatment will take place in the long-term are:• To provide certainty that future regional wastewaterneeds can be met in an effective, efficient and wellplanned way that will optimise the use of available funds;• To avoid the acquisition or holding of land for futurewastewater treatment purposes that will not ultimatelybe used for that purpose;• To avoid uncertainty for communities living near sitesthat have been identified as possible regional facilitiesbut will not ultimately be used for wastewater treatmentpurposes;• To ensure that land use planning in the general localityof future regional facilities recognises and providesfor the relevant activities at the site and minimisesthe potential for conflict to result from inappropriateadjacent land uses (This need to take into accountpossible competing land use issues) ; and• To provide certainty for wastewater planners so thatall works undertaken in the short and medium term arecompatible with long-term objectives, so as to minimiseinappropriate solutions and wasted expenditure.Trunk Sewer Upgrading Needsas Part of the Future RegionalWastewater StrategyAdditional trunk sewer capacity is required to provide forgrowth in central Auckland, Waitakere City and longertermin Manukau City. The initial investigations of trunksewer options undertaken as part of the TWSPP andassociated investigations were wide ranging. They includedconsideration of duplicating the existing trunk sewersfrom central Auckland to the Mangere WWTP and newtrunk sewers from central Auckland via new routes to theMangere WWTP, the Rosedale WWTP and possible newtreatment plants in central, west and south Auckland,along with storage solutions.South Auckland treatment plant options were subsequentlyexcluded from the current Strategic Plan as there is nocertainty on future development trends and population tobe served. A preliminary assessment of initial options totake flows from central Auckland to the Managere WWTP,Rosedale WWTP and possible sites in central and westAuckland was undertaken as part of Report TW 40. Thisshowed that continued use of the Mangere WWTP is theonly realistically practicable option in the short to mediumterm.Duplication of the existing Orakei main sewer and EasternInterceptor was compared against a partially new route tothe Mangere WWTP, as summarised in the following table.Short Term:The HillsbouroughTunnel andManukau Siphonneed to beduplicatedDuplication of Orakei Main Sewer,Eastern Interceptor, Manukau Siphon,Hillsborough Tunnel and other sewersto provide same level of serviceas Central InterceptorTotal length ofpipesIndicativecapital costConstructionconsiderationsTiming ofbenefits50 kilometres 22 kilometres$1,100 million $700million to $800 millionRoute follows route of existing pipes in built up area,with associated difficulties in avoiding existing services,requiring combination of open cut and tunnelling withmajor potential for traffic and other community disruptionRequirement to complete majority of works beforebenefits of reduced overflow potential realised, likely tobe after 2026Construction of new Central Interceptor,incorporating second Manukau Siphonand Hillsborough TunnelTunnel construction for whole length with no significantdifficulties in avoiding existing services or potential fortraffic and other community disruptionStaged development possible with main benefits achievedbefore 202044When considering options to provide the required futuretrunk sewer capacity, the following factors need to betaken into account:• The Manukau Siphon and the Hillsborough Tunnel - twomajor components of the existing western interceptortrunk sewer - will require duplication in the mediumterm. The existing 50-year old pipes cannot be inspectedor maintained and there is an increasing likelihood offailure as the pipes further age;• The new Hillsborough Tunnel can be constructed as astorage tunnel with relative ease;• By providing additional trunk sewers from the end ofany new Hillsborough Tunnel to Pumping Station 25 (StGeorge), which serves Waitakere City, and to a locationnear Western Springs or Chamberlain Park, the majortrunk sewer upgrading requirements can be met;• This solution will require less investment by anestimated $300 million to $400 million dollars and,in combination with the above will have the followingadditional benefits:• All flows in the trunk sewer will be transferred to theMangere WWTP by gravity, avoiding the need to useenergy for pumping;• The volume of Watercare’s wet weather overflows willreduce by more than 70%;Final 2008 Strategic Plan – December 2008

• Storage in the new tunnel will allow peak flows to bebalanced out so that perhaps 99.5% of all flows to theMangere WWTP will receive full treatment, with publichealth benefits to users of the Manukau Harbour (actualpercentage subject to detailed checking);• The storage facilities may allow a lower cost solutionfor addressing issues associated with some combinedsewers owned and managed by Auckland City/Metrowater.The trunk sewer augmentation programme described aboveis currently known as the central interceptor. It will provideadvantages to all of the main urban councils, as follows:Auckland CityProvides for short-term growth needs, reduces wetweather wastewater overflows, allows flexibility foraddressing combined sewer separation and improves waterquality in Waitemata and Manukau harbours.Manukau CityProvides for medium-term growth needs and improveswater quality in Manukau Harbour, in particular, with nomore than minor change in effects at the Mangere WWTP.Waitakere CityContributes to short and medium-term growth needs andimproves water quality in Manukau Harbour, in particular.North Shore CityDelays need to use Rosedale or other regional facility.Selection of the RecommendedSecond Regional WWTPIn the intervening time since the main options evaluationprocess was undertaken, it has been possible to refineoverall directions as outlined above. The choice of thesecond future regional WWTP can now come down to astraight comparison between Rosedale (NE), a site in westAuckland (NW), and a possible site in central Auckland(Central).Three different methods were used to undertake thiscomparison, as follows:• Comparison of the three treatment plant and dischargeoptions based on scores from the original evaluation –social, cultural, environmental and legal, technical, riskand timing, but using a smaller group of criteria;• Listing a series of questions relevant to the suitabilityof options for treatment and disposal and scoring eachof the three options under consideration against thequestions; and• A generic overview of relevant factors.Each is considered in turn below.Comparison of Options Based onOriginal ScoresThis is summarised for a reduced list of criteria inthe following table. The figures in brackets representpopulations served of 0.5, 1 and 1.5 million people.Short toMedium Term:Additional trunksewer capacityis required forAuckland andWaitakere growthBasis of Comparisonof optionsOrder of Scoring from Best to Worst (1 to 5)1 2 3 4 5Social criteria only NE (1)/Central (Equal) NW (0.5) NE(1.5)Cultural criteria onlyEnvironmentalcriteria onlyCombined social, cultural and environmental criteriaCombined social, cultural and environmental criteria,where social is weighted three times more important thancultural and environmentalCombined social, cultural and environmental criteria,where cultural is weighted three times more importantthan social and environmentalCombined social, cultural and environmental criteria,where environmental is weighted three times moreimportant than social and culturalLegal, technical (Note timing excluded in the reducedcriteria as not critical)NE(1)NE (1.5) Central NW (().5)/NW (1)(Equal)NW (1.0) NW (0.5) NE(1)NE(1)NE(1)NE(1)NE(1)NE(1)NE (1.5)NW(1)CentralNE (1.5) Central NW (0.5) NW (1.0)Central NE (1.5) NW (0.5) NW (1.0)NE (1.5) Central NW (0.5) NW (1.0)NE (1.5) Central NW (().5)/NW (1)(Equal))NE (1.5) NW (0.5) NW (1.0) CentralThe table shows that the use of the North East WWTPscores better than other options overall, based onconsideration of social, cultural and environmental criteriaonly, even when scores are weighted. Economic criteriaare not sufficiently different between options to alter thepositions.An evaluation based on legal and technical criteria alsoidentifies the North East WWTP as the preferred option.45Final 2008 Strategic Plan – December 2008

Long Term:The North EasternWWTP will havecapacity to treatother regionalwastewater outto 2100Comparison of Options Based onKey QuestionsA list of key questions is set out in the following table .The questions are related to how treatment and dischargefacilities might be accommodated in different locations.Each of the three options of a north east, north west andcentral facilities is then scored against the questions from1 to 5. 1 is the most positive in terms of suitability and 5 isthe least favoured.It can be seen that the North East WWTP scores best witha score of 17, the North West WWTP comes second witha score of 23 and the Central WWTP third with a score of34. The scores for the North West and Central plants arepotentially optimistic, meaning the gap between them andthe North East WWTP could potentially be greater.Evaluation of Options Based on Suitability in Terms of Pertinent QuestionsQuestionDoes a site for wastewatertreatment exist with therequired land area, and if not,is there a high likelihood that asite can be foundExisting Rosedale WWTPNew North WesternWWTPNew Central WWTPAnswer Score Answer Score Answer ScoreYes 1 Yes 1 No. Because of theintensely developedurban area withinwhich the site would belocated, low likelihood offinding a site5Is use of the site for wastewatertreatment purposes consistentwith Regional and District Planprovisions or could it be madecompatible without unduedifficultyYes, but will need jointplanning to ensurecompatability betweencompeting land uses.1 The site is not zoned forthe purpose at presentbut on a broad initialassessment its use forwastewater treatmentpurposes could becompatible withadjacent land uses2 There is unlikely to beany area in the localitywhere the treatmentplant could be sited thatcould accommodate theplant without major landuse planning issues4Can the use of the site forthe proposed extensionor implementation ofwastewater treatment facilitiesbe undertaken withoutunacceptable effects on theenvironmentYes, with appropriatecovering of tanks, noisecontrol and landscaping.There are many plants allround the world whereeffects are managed toprotect adjacent landuses1 As Rosedale 1 Generally as Rosedale,but significantconstruction effectslikely2Does the site have reliableservices available (includingroads, power supply, watersupply, communications) or canreliable services be providedwith relative easeYes, being in a fullyserviced area1 Many services wouldhave to be provided ina rural environment.Reliable power supplywould be more difficultto ensure compared tourban areas2 Yes, being in a fullyserviced area1Is the site desirable in termsof minimising energy costs forgetting wastewater to and fromthe sitesLess than ideal becauseof 45 metre elevation ofsite above sea level3 Least attractive of sitesbecause of site elevationof 55 to 60 metres abovesea level. An alternativesite could be used3 Best of three sites withrelatively low energyrequired to pump flowsto and from site, butnot ideal2Can peak wastewater flows behandled with relative ease ifthe site is used as a regionalplantSome limitations, butgenerally yes, with flowbalancing capacityavailable in ponds (evenwith reduced area) andprovided appropriateflow balancing providedin network2 Generally as Rosedalebut may requireconstruction of flowbalancing pond prior todischarge to minimisesize of outfall pipe2 Less suited to peakflow treatment becausemembrane plant thatwould be used wouldnot handle peak flowseconomically3Can biosolids be managed withrelative easeYes, generally as atpresent, but off-site useand/or disposal can bean issue2 As Rosedale 2 Unlikely to be roomfor on-site biosolidstreatment of any kind,requiring facilitieselsewhere446Does a method of effluentdisposal exist with sufficientcapacity to meet futureneeds without undue effectson the environment and/orthe community, and if not, isthere a high likelihood that adischarge location can be foundand consentedYes, with appropriatetreatment. Low potentialfor undue effects onthe environment and/orthe community. Someaugmentation of theproposed new outfallcould be required2 There is no existingdischarge. Options doexist with low potentialfor undue effects onthe environment and/or the community. Asthe discharge wouldaffect environment andcommunity not currentlyaffected, somewhatless favourable thanRosedale in terms ofoverall effects3 Generally as NorthWestern WWTP3Final 2008 Strategic Plan – December 2008

QuestionCan use of the site be staged ina way that avoids major upfrontexpenditureExisting Rosedale WWTPNew North WesternWWTPNew Central WWTPAnswer Score Answer Score Answer ScoreNot entirely, but easiestto stage and minimiseupfront costs of alloptions. Main upfrontcosts over and abovesunk costs would be thepipeline to the plant andadditional treatmentcapacity for say 100,000people2 Much less opportunityfor staged developmentand expenditure thanRosedale. In addition tothe pipeline to the plant,initial site developmentcosts, servicing andsupport infrastructurecosts and, in particularthe cost of the dischargesystem would need tobe added at a minimumlikely additional initialcost compared toRosedale of around$173 million3 Generally as NorthWestern WWTP butwith a minimum likelyadditional initial costcompared to Rosedaleof around $334 million4The North EasternWWTP will havecapacity to treatother regionalwastewater outto 2100Taking an overall balanced viewof the effects of the option onlocal communities, how do thedifferent options compare?Broadly speaking, theoption would not affectany communities thatare not affected by thecurrent situation andexisting effects wouldnot be significantlychanged by the option1 As well as thecommunities affectedby the existing Rosedalefacility, communitieswhich are not currentlyaffected, at both thenew treatment plant anddischarge sites, would beaffected to some extent,albeit to a limited extent2 Generally as NorthWestern WWTP butwith potentially greaterconstruction effects inaddition2Taking an overall balanced viewof overall project risks, how dothe different options compare?Lowest risk option asfacility is alreadyconsented for theintended purpose,treatment plant siteconditions are knownand relatively straightforward and there willbe no significant risksassociated with a newdischarge1 Somewhat higherrisk because of lackof consents andsignificantly higher risksassociated with a newocean outfall2 Significantly higherrisks because of thelack of an obvioussite, lack of consents,major undergroundconstruction for thetreatment plant andrisks associated with anew outfall4Other questions could also be asked, including which option would allow maximum flexibility to respond to changes inneed for wastewater services. A seperate investigation again showed the Rosedale option would allow greater flexibilty.47Final 2008 Strategic Plan – December 2008

The NorthEastern WWTPis the preferedsecond regionalwastewaterfacility based oncurrently availableinformationGeneric Overview of OptionsThis overview is based on comparing options to provideadditional wastewater treatment capacity for 500,000people and possibly up to 1,000,000. In reality, a figureat the lower end of the scale is more likely if treatedwastewater reuse is actively pursued and new technologiesover the next 30 to 40 years allow increased efficiency inremoving nitrogen from wastewater.At a very high level, the choice will be influenced by:• Whether facilities can be developed without undueeffects on communities and the environment;• Which option involves least risk;• Which option offers most flexibility to deal with futurechange; and• Which option is most easily affordable, assuming allmeet generally equivalent performance standards.By using a very simple direct comparison of the threeoptions using scores allocated by independent groups ofexperts, the North Eastern WWTP is preferred on almostevery count.In terms of the questions listed in the table overleaf, theNorth Eastern option is once again preferred on all countsindividually and overall, and the Central WWTP is leastfavoured by a substantial margin.With specific regard to the central plant, the followingneed to be considered:• There is no existing land-based site for a treatmentplant and no real expectation that one will emerge inthe future;• While reclamation is theoretically feasible, experiencein New Zealand has shown it to be almost impossible toget consented;• A central treatment plant would be membranebased and poorly equipped to deal with peak flowseconomically;• Biosolids would require off-site treatment withconsiderable complications and additional cost;• Any treatment plant development would requirecoordination with many different organisations, whichmakes a successful outcome less likely;• Any central treatment plant would be very high cost andwould place additional pressure on available funds; and• Obtaining consents for both the treatment plant anddischarge could be impossible.While there are sound reasons for wanting to pursue acentral treatment plant, the factors against such an optionbeing realistic are likely to be insurmountable. They arecertainly sufficient to make any reliance on a successfuloutcome imprudent to say the least and of too high risk tobe taken further at the present time.Overall, in a straight comparison between north east andnorth west options, the north eastern option is favouredfor the following reasons:• No significant increase in effects, if any, compared toexisting consented limits;• Minimises effects on communities overall;• Best addresses cultural issues, of the options available;• Maximises benefit of existing resources and investmentat Rosedale and the associated outfall;• Will provide financial benefits to North Shoreratepayers;• Will extend the expenditure profile more than any otheroption in terms of time, with benefits to all regionalratepayers;• Requires less energy to pump wastewater to thetreatment plant unless a new north west site is chosen;• Lower overall construction risk.In a fully regional context, which is the premise of theTWSPP, there do not appear to be any compelling reasonsfor not using Rosedale as a second regional facility,provided appropriate controls are put in place. Accordingly,this Strategic Plan proposes that Rosedale is the secondregional wastewater facility.This final choice will need confirmation prior to physicalconstruction works being undertaken. It will be importantto secure the Rosedale WWTP for future regional purposesby land use designations to avoid use of the land for otherpurposes.The central interceptorconcept includes:Duplication of Manukau Siphon and HillsboroughTunnel.Mitigation of 70% of trunk wastewater dischargesto Waitemata Harbour.Network capacity augmentation for growth inAuckland City, Waitakere City and longer termManukau City.Opportunity to be jointly optimised with the sewerseparation programme and also mitigate nearbylocal network operator discharges.Online storage sufficient to balance peak flows tothe Mangere WWTP, significantly reducing bypassevents.A flow transfer station (hub) to divert flows longerterm enabling flow sharing between regionalWWTPs.48Final 2008 Strategic Plan – December 2008

A Vision we can all shareThis document sets out the Three Waters Vision for theintegrated management of water supply, wastewaterand stormwater services in the Auckland Region. It is ahigh-level document that outlines the Auckland WaterIndustry’s collective aspirations to 2050, while ensuringorganisations have flexibility to innovate and respond tolocal requirements.Preparation of the Vision was initiated by AucklandCity, Manukau City, North Shore City, Papakura District,Rodney District and Waitakere City Councils in their roleas Shareholders of Watercare Services Limited. Watercarefacilitated preparation of the Vision, with input from awide range of regional stakeholders.This Vision Statement applies tothe Auckland region as shown.A vision wecan allsharePart EWaterA list of approveddemandmanagement toolsSupply49Final 2008 Strategic Plan – December 2008

Water supply- our currentAucklandsituationEcowater 13%North Shore City 15%Metrowater 39%Water delivered to households andbusinesses through a piped supplycomes from one of three mainsources• surface water stored behind dams;• groundwater; and• river water.Watercare, the region’s bulk provider of water services,manages those sources, providing a source water droughtsecurity of 1:200 years (based on draining the reservoirs toempty) or 1:50 with 25% remaining available.Auckland has moderate consumption by comparison toother cities in New Zealand and world wide. On average,Aucklanders consumes less water than Americans andAustralians but often more than those living in someEuropean cities. This lower level of consumption in Europeprobably reflects the longer term water efficiency policies inplace in those countries and the price of water.Forecasts made in this strategic plan for Auckland’s futurewater needs are based on today’s average demand of around300 litres per person (combined domestic and industrialuse and leakage). That means that Auckland currently needsan average of 370,000m 3 /d (or around 150 Olympic sizedswimming pools) to be put into supply every day.If this level of water use continues, future average needscould be more than 630,000 m 3 /d by 2050. This would requirealmost two more Waikato treatment plants. By 2100, wecould need more than 900,000m 3 /d or at least another threeWaikato treatment plants.The first increase in new water sources to meet our currentaverage demand is forecast for 2026.Water demand increases on the hottest days of summer.Water systems in Auckland are designed to provide almosthalf as much again during the summer over the averageannual demand. There is sufficient source water available tomeet this seasonal increase until 2026. However, additionalwater treatment facilities are forecast to be needed by 2010.There are opportunities to reduce consumption in Aucklandand, as a result, the need for new water sources. This willrequire the use of water efficiency and water demandmanagement methods, subject to cost effectiveness andcommunity acceptability.This strategic plan proposes asubstantial reduction in daily wateruse per person to delay the needfor new water services.Auckland Region’s Water Trunk Supply NetworkUnited Water 4% Rodney District 2% FranklinManukau Water 27%NorthShore CityCurrent regional water use as apercentage of the totalWaitakereWAITAKEREDAMCityUPPERHUIADAMWAIT AK E R ETR E AT ME NTP L ANTUPPERNIHOTUPUDAMLOWERHUIADAMH U IA V IL L A G ET R E A T ME NT P L A NTLOWERNIHOTUPUDAMHUIATR E AT ME NTP L ANTO NE HUNG ATR E AT ME NTP L ANTManukauCityAR DMO R ETR E AT ME NTP L ANTCOSSEYSDAMPapakuraDistrictHAYSCREEKDAMWAIROADAMUPPERMANGATAWHIRIDAMMANGATANGIDAMDistrict50WAIK AT OTR E AT ME NTP L ANTWAIKATO RIVERFinal 2008 Strategic Plan – December 2008

Water consumptionin litres per person per dayLocal AuthorityAreaAveragepersonal useTotal useRodney District 180 250Papakura District 190 330Auckland City 185 355Our overall community watersupply position2008 Averagedaily useTotal treatmentcapacity availableVolume(1000m 3 /d)375570Year capacityexceeded2026AucklandRegion -our currentwater supplysituationManukau City 190 305North Shore City 200 260Average volumeof treated wateravailable395Waitakere City 165 233How we use water inlitres per person per day(Where * means no surveyed data specificallyfor Auckland exists)Drinking, kitchenand washing*Indicative use inlitres25Washing* 110Toilets and otherhousehold use*35Garden watering* 15Industrial andcommercial usewater such as firefighting8024System losses 152008 Peakdaily usePeak volume oftreated wateravailable4955702010Water sources currently used forurban supplySourceLakeRiverDaily volume incubic metres95,000,000 m 3 (Total available)150,000 m 3 /d (Currently allowedin resource consents)Groundwater 21,000 m 3 /dRoof waterTreated wastewaterUnknown but small 60,000* (Including recyclestreams)Based on 2008 forecast.* Source 2004 Audit of RecycledWater at Mangere WWTP.California 440Indiana 220Total 305New Jersey 275Thames Water London 200Helsinki 180Gothernburg 180Stockholm 185Netherlands 120Domestic Demand(Litres/head/day - 2005/06)Auckland 180Wellington 248Hamilton 230Palmerston North 275UrbanDomesticWater Use inNew ZealandWorldwide Domestic Consumption(Litres/person/day - 2004/05)Dunedin 190South Australia water Adelaide 240Yarra Valley Melbourne 210Gold Coast Water Brisbane 248Auckland 180Hamilton 23051Final 2008 Strategic Plan – December 2008

Water supply– Learningfrom thepastWater consumption dropped in the late 1980s and early1990s even though population continued to grow. Thisoccurred as a result of drought, the relocation of meatworks and other manufacturing industry out of the waterservice area and universal water metering. Since then ouroverall consumption expressed as volume per person hasbeen stable.Population and Average Gross Consumption Per Person Per Day1,400,000Population Connected to Urban Supply Network1,200,0001,000,000800,000600,000400,000300,000PopulationAverage Consumption Per Person12 Value Moving Average (Average Consumption Per Person)500400300200100Litres Per Person Per Day00Jun 1971Jun 1976Jun 1981Jun 1986YearsJun 1991Jun 1996Jun 2001Jun 2006Growth in population over recent years has seen a proportional increase in the total water consumed.Population Growth and Total Water Consumed1,400,000450,000Population Connected to Urban Supply Network1,200,0001,000,000800,000600,000400,000300,000Average Pop for Year EndSales (m3/d)400,000350,000300,000250,000200,000150,000100,00050,000Total Water Consumed (m3/d)0Jun 1971Jun 1976Jun 1981Jun 1986Jun 1991Jun 1996Jun 2001Jun 20060Years52Final 2008 Strategic Plan – December 2008

The Auckland region has an excellent network of dams inthe Hunua and Waitakere Ranges.Large pipe systems bring water to the urban area witharound 80% of the volume moved under gravity. This isvery efficient and climate friendly.Local distribution pipe work moves the water tohouseholds and businesses. All pipe work everywhere inthe world leaks to some extent. Maintaining pipe networksat the minimum economic level of leakage is a desiredoutcome for all responsible network operators.Levels of leakage are discussed in many ways, often aspercentages. This term should be avoided as climaticfactors can distort comparisons between years andorganisations. One of the better methods is to workout both:• The quantities that are lost over the total length of pipein the system - the more pipes there are the harder itcan be to find and fix leaks and;• The quantities lost over the number of propertiessupplied - the greater the number of connections toproperties, the higher the leakage is likely to be asexperience shows that losses occur at joints. Thereforethe higher the number of joints the higher the leakagecan be expected to be.Using these measures to compare Auckland with othersaround the world indicates that Auckland has a betterleakage record than many cities.On average around 40,000 m 3 /d of water is lost throughleakage around Auckland. The price of this lost water isapproximately 13 cents per property per day.Finding and fixing leaks can be a very effective way ofsaving water although there will be a time when the costof doing so is greater than the cost of developing a newsource.Water supplylosses areestimatedat around40,000 cubicmeters perday30Estimates of Leakage InternationallyLondon25StockholmCubic metres per km per day201510HelsinkiGothenbergUK, Midlands5010Sydney WaterMalmoSub set of graph for AucklandAucklandBest & Worst Dutch20 40 60 80 100 120 140 160 180 200 220 240 260Litres per property per day(Worldwide Information from: Security of Supply, Leakage and Water Efficiency – 2005-06 Ofwat, UK)Estimates of Leakage in the Auckland RegionAucklandhas a betterleakage recordthan manycities9Cubic metres per km of main per day876543North Shore CityManukau WaterWaitakereRodney DistrictMetrowaterUnited Water21020 40 60 80 100 120 140 160Litres per property per day(Auckland Information from: Auckland Water Industry Annual Performance Review – 2005-06)( Note: Watercare losses notshown as overall leakage is low.Trunk network has few directconnections and a relativelyshort networks have largediameter mains).53Final 2008 Strategic Plan – December 2008

Water Supplyfor the FutureDemandForecast750,000A forecast of future demand for water is prepared everyyear looking ahead for at least 50 years. This identifieswhen new sources of water will be required. The forecastidentified the need for a new source in 2026.Water Demand Projection100 MLD FutureSource 2043100 MLD FutureSource 2062650,000There are a number ofways to respond to this• Build new resources to ensuresupplies are available, requiringcapital investment and manyyears of planning to ensureconsents can be gained andsources can be developed.• Reduce the demand for waterthat will be required, spendingmoney on techniques that usewater efficiently.• Using both of the methodsoutlined above.Volume (m 3 /d)550,000450,000350,000250,0001999Waikato IA 2002Waikato IA 20042009Waikato II 20142019Waikato III 2021100 MLD FutureSource 2026Regional demand projection - medium growth senarioRegional demand projection - high growth senarioLocal Network Operators’ demand projection2029Years2039Regional demand projection - low growth senarioHistoric UseSource Planning Line Adjusted204920592069Watermanagement– supply anddemand- the toolsavailableWe can manage demand by usingsome or all of the followingoptions:• Changing the behaviour of water users.• Continuing with efficient practices and operations.• Seeking alternative sources.Reduce demand by changingbehaviour• Promote efficient water using devices.• Educate consumers about the implications of their useand assist with information about that use.• Provide incentives to reduce consumption, such as theuse of pricing mechanisms that change behaviour.• Undertake audits of household, schools and industrialwater use.Implement efficiency measuresManage losses from the pipe system by seeking out andrepairing leaks and managing the pressure of the water sothat losses are minimised.Impose restrictionsLimit non-essential use, particularly household outdooruse and targeted industrial use, for short periods in timesof drought.collected in rain tanks, grey water, groundwater forexternal use and/or treated wastewater.Manage excess waterCapture water not needed immediately and store it, forexample, by returning it to aquifers for re abstraction at adifferent location and timing.Add additional water supplysourcesAugment existing supplies with new sources within theregion and/or import water from outside the region.Each of the water efficiency and demand managementoptions are valid mechanisms for managing water buteach requires an appropriate level of investment to achievethe benefits. Experience also indicates that it is easy toover-estimate benefits and under-estimate the costs andthe time taken to realise the benefits of implementingthe options. Some options should be “business as usual”for the water industry (like leak control), while others willneed to be applied in specific local circumstances. All maybe valid in particular circumstances and their applicationshould be regularly reviewed, especially as some can haveimportant additional benefits for other parts of thewater cycle.Use or recycle stormwater andtreated wastewater54Treat and recycle water that has been used and substitutepotable water use with other sources such as stormwaterFinal 2008 Strategic Plan – December 2008

AucklandWaterManagementPlan 2004- our agreedway forwardThe Auckland WaterManagement Plan “From the Skyto the Sea”, published in 2004, setout an approach to water efficiencythat the region would take. Theobjective was to reduce per capitawater demand by 5% over 20years.The Auckland Water Management Plan (AWMP)“established a comprehensive and unified approach tomanaging the existing and future water needs of theAuckland region in a sustainable, wise and efficientmanner”. The plan set out a number of actions to beimplemented by local network operators.The review of those action plans identified in the AWMPwas carried out in late 2006. This demonstrated that somehave been more successful than others.Experience around the world suggests that when thereisn’t a drought, achieving such savings can be difficult andso far that has proven to be the case in Auckland.Since 2004, consumption hasincreased – the 2008 target wasto reduce average consumption ofwater to 294 litres per head per day,whereas the actual consumption in2008 was 297 litres per head per daywhich was set as the 2005 target. Inaddition, the trend line shows increasingrather than falling consumption.Changing behaviour requires renewed effort to enablewater efficiency to be effective. This Three WatersStrategic Plan anticipates 15% reduction in per capitaconsumption by 2025 will be achieved, which will partlycompensate for an increase in population. Implementingthese changes will require commitment to a range ofactions and the Strategic Plan anticipates an additional10% reduction in overall water demand through thebeneficial use of stormwater and treated wastewater overthe same period. This will give a total of a 25% savingsin demand.The next two pages of this document outline aseries of questions that apply in 2008, and the likelyanswers. The options that have been specificallyconsidered for the Strategic Plan are laid out in theadditional two tables as:• Opportunities to reduce demand;• Opportunities to improve supplies.55Final 2008 Strategic Plan – December 2008

Water supply– 2008questions andanswers forthe futureQuestion Answer Influencing factors Approach used in ThreeWaters PlanningWhat role willwater efficiencyand demandmanagementplay in futurethree watersmanagement?Because the single largestdriver for more water ispopulation growth, waterdemand management orefficiency could defer the needfor a new water source by 10 to15 years.Water efficiency and demandmanagement will depend on thecommunity’s willingness to savewater.Local network operators andCouncils to advise Watercare ofsavings they can achieve andcommit to, as failure to meetagreed targets will lead to watershortages.Can significantreductions inwater use bemade by reducingsystem losses?Reducing the losses frompipes can be cheaper thandeveloping a new sourceof water, but needs localinvestigations by each localnetwork operator. There is aminimum economic levelof leakage.The cost of finding and fixingleaks and the value of waterpaid for by customers but notused.The long term water demandforecast assumes that all LNOswill achieve the current bestpractice in the region.What role will theuse of stormwateras a substitutefor mains waterplay in futurethree watersmanagement?Two options exist –households using tank waterto replace piped water fornon drinking purposes. At acity scale, storm water can berecharged into the ground forlater abstraction.Depends on economics - Allnew households could berequired to install a rain tankwhen the house is built. This isencouraged by some but not allcontacts. Collection, treatmentand supply of stormwaterfor non potable uses may beused on a development scale.Generally only supported forno potable purposes by HealthDepartment.The long term water demandforecast assumes that districtplans will be changed and thata proportion of new houses willhave rain tanks. No allowancehas been made for retrofitting.Overall it is envisaged thatstormwater and treatedwastewater will meet 10% ofrequired water supply needsby 2025.What role willthe beneficialuse of treatedwastewater asa substitute formains waterplay in futurethree watersmanagement?Beneficial reuse of treatedwastewater is unlikely to beacceptable on a large scale inAuckland. The principle areasof opportunity are industrialuses and irrigation of sportingfacilities. This is seasonal anduneconomic at the presenttime.Social acceptability is a keyinfluencing factor, with few inthe community accepting directre use as a viable option atpresent. If it costs more to treatand supply wastewater whencompared to drinking water theproposition will be unattractive.The long term water demandforecast assumes that somere use will occur but in only alimited number of industrialapplications in the short tomedium term future.Can we usetreatedwastewater fordrinking?Technically yes, but few placesin the world do. Namibia isprobably the only example ofthis occurring over a sustainedperiod.Social and cultural influencesmake this unattractive at thepresent time.No allowance made in thewater demand forecast for theuse of treated wastewater asa substitute for drinking waterpurposes, but possible mediumto long term future.What effectwould increasingthe price of wateruse of pricing /tariffs have onwater use?Evidence from around theworld suggests that as theprice of water increases so thedemand falls. Sophisticatedtariffs have been developedthat try to recover the costof water provision, especiallywhere there is a significantseasonal influence.Most households pay for waterbased on the quantity that theyuse. The use of a seasonal pricecould influence the behaviourof customers when water is inhighest demand in the summer.Any prices would need toensure that all health andwell-being needs could be met.Forms of differential pricingmay have potential to be usedas an efficiency tool, accordingto overseas experience.Price has been used as a factorin the long term scenario,but indirectly , based on allLNOs introducing charges forwastewater disposal. Evidencein Auckland does suggest thata reduction in water use doesoccur when wastewater chargesare introduced.56Final 2008 Strategic Plan – December 2008

Question Answer Influencing factors Approach used in ThreeHow will Watercareplan to ensureenough wateris availablewhen there isuncertainty aboutwhat savings canbe made?Watercare will continue tocarry out long term planningrevising demand forecasts onan annual basis, looking aheadat least 20 years. This givessufficient time for planningand investment.The biggest single influenceof water demand at this timeis the growth of Auckland’spopulation. Average use perhead is fairly stable but thenumber of people in the regioncontinues to grow.Waters PlanningThe water demand forecastmakes different assumptionsabout the success of waterefficiency measures. Thisprovides upper and lowerboundary estimates of whatmight happen, enabling adebate about how much effortthe community wants to make.Water supply– 2008questions andanswers forthe futureWhere will thenext main sourceof water be?There are a number ofpossibilities, ranging fromexpanding the Waikato source,to new reservoirs or riverabstractions from the northof Auckland, or increasing theabstraction of groundwater.Making savings on demandwould mean that a new sourceisn’t needed for many yearsUnless these savings arerealised, a new source will berequired by 2026.Two options are beingconsidered - a northern supplysource and associated trunkmains and an augmentedsouthern supply source andassociated trunk mains.How will Watercareensure long-termsecurity of supplyfor North ShoreCity and RodneyDistrictWatercare will maintain itsfocus on the risks presentedby pipes supplying the norththat have to use the two majorbridges in the region.Developing a source or majorstorage to the north of theWaitamata Harbour willprovide increased security.Providing additional supplypipes under harbour isproposed.Depends on the sourcechosen (see above), but if theWaikato River continues to beextracted, a new water mainunder the Waitemata harbourwill be provided.When will the nextsource of water bedeveloped?If behaviour doesn’t changeforecasts suggest around2026.Making savings on demandwould mean that a new sourcecould be deferred possibly byup to twenty years.A new source will be requiredby 2026 unless effectivedemand managementmeasures are in place.When will treatedwater capacity beupgraded?Forecasts for water demandat the hottest time of theyear determine how soon newtreatment will be required. Atpresent 2010 is the expecteddate.The summer weather hasa very big influence onpeak demand. Becausethat is out of Watercare’scontrol, investment mayneed to be made to ensurethat appropriate suppliesare maintained. Demandmanagement around that peakdemand could put off theneed for investment.The long term water demandforecast works on the forecastaverage need for wateraccepting that short duration,seasonal needs are importantPipe networks are usuallydesigned with those needs inmind.What effect willchanges have inNew Zealand’sdrinking waterstandards have?There are proposed changesto New Zealand’s DrinkingWater Standards expected tocome into effect in 2008/09.The proposed changes couldrequire substantial investmentin order to ensure compliance.Raw water sources, treatmenttechnology, pipeline materialsand residence time of water inpipelines all have an influenceon water quality.A specialist investigation isbeing undertaken as a part ofthe Three Waters programmeto accurately determine themagnitude of the effectsproposed drinking waterstandards will have on theAuckland region.57Final 2008 Strategic Plan – December 2008

Water supply– quantifyingopportunitiesto reducedemandOption Method Potential Savings Certainty ofReduce demand Price Mechanisms. Potential savings of around2,000m 3 /d, assuming allLNOs introduce volumetricwastewater charging by 2012resulting in a 2.4% reductionacross the region.ImplementationVolumetric wastewatercharges are now in place fortwo of the six local networkoperators receiving a watersupply from Watercare. Anumber of the remaining LNOsare reviewing whether chargescould and should be applied.This strategic plan assumessix years will be requiredbefore the change in policy isimplemented.Target OutdoorDiscretionary Use.Rodney District Counciltargeted 2004/05 summercampaign effectively reducedwater demand below supplyavailable.Five of the six LNOs do not askfor customers to make savingsduring summers periods. Thispolicy is likely to stay in place.Therefore, no water savingsare included in this strategy.These types of restrictionsare only valid for managingsummer peaks.Water Audits – Commercialand Industrial.Savings depend onindustries targeted. Savingsof 2,000m 3 /d, have beenassumed.Audits are a positiveopportunity to work withlarge users as savings in waterare likely to save cost of thewater bill. Many cities aroundthe world have found thatindustry can make a greaterproportion of savings thanindividual households.Restrictions andRegulationChanges to bylaws andBuilding Codes, requiringwater efficient devices to beinstalled in new buildings.To date the main changeof relevance has been theaddition of rain tanks forstorm water attenuation.There is some conflict betweentanks for storing rain andthose for slowing down roofwater runoff. The certaintyof implementation is low butthe scenario assumes up to80,000m 3 /d can be saved by2100 by the use of roofwater.Garden Watering Restrictions.Restrictions do influence peakdemand, but likely savingshave not been quantifiedfor Auckland. Increaseddevelopment density over timeis likelyto reduce the demand forgarden watering.No change to current policy sono savings allowed.58Final 2008 Strategic Plan – December 2008

Option Method Potential New Water Certainty ofIncrease Supplies New Sources – Groundwater. The Onehunga aquifer hasan estimated 60,000 m 3 /d ofwater available for potentialsupply. Only half this is usedat present. A further 30,000m 3 /d is potentially availableas a future source for urbanwater supply, some of whichis already used privately. TheWestern Springs aquifier andThree Kings Quarry also havepotential.ImplementationIncreasing a source thatalready provides water canbe expected to be an easierand cheaper option thandeveloping one from new.Quantifying the amountof water available (yield) isnot precise, so the actualadditional quantity available issomewhat uncertain.Water supply– qualifyingopportunitiesto improvesupplyNew Sources – Surface Water.These vary depending on thelocation and source chosenbut range from 20,000 to150,000 m 3 /d. Auckland CityStonefields development beingpursued.There is enough wateravailable from sources suchas the Waikato River andother sources to meet thefuture needs of Aucklandthrough to 2100 and beyond,in association with prudentdemand management.Substitution – recycle/ reusewastewater and stormwater.Wastewater treatment andbeneficial reuse is limited atpresent to existing wastewatertreatment plants. There areno plans for direct reuseof treated wastewater forhousehold uses, but there areopportunities for industrialreuse where the recycledwater could replace drinkingwater.Investigations have shownthat there are industries thatcould use recycled water.They are limited in numberand volume today but couldincrease in the future. Thisstrategy takes a long view andassumes use could increasefrom around 5000 m 3 /d in2015 to perhaps 20,000 m 3 /dby around 2025.Substitution – rain watertanks.Rain tanks can be included inall new houses that are builtso the benefits will be gradualover time. No assessmentof the potential for retrofitting tanks in existingproperties has been made asthe costs are likely to be veryhigh ($15,000-20,000 perproperty).Without some form ofdistrict plan that enforcesthe rate of installation ofrain water tanks the benefitcannot be guaranteed. Thisplaces a significant riskon the source provider. Aregional investigation willbe undertaken to confirmregional role of the rainwatertanks in the future.Managing ExcessWaterAquifer recharge.Storm water recharged andstored in the Central AucklandIsthmus could provide additionwater in the city For thisstrategy up to 20,000 m 3 /dhas been allowed, although itcould be more.Recharge of the aquifer ispossible although the urbannature of the city could keepvolumes below the maximumcalculated.59Final 2008 Strategic Plan – December 2008

Reviewof currentstatus of“Sky to theSea”ProgrammeKey Watercare Metrowater North Shore City Council United Water Waitakere Manukau Water Rodney District Council Franklin Auckland CityManagementOptionWaterMeteringWaterAccountingand LossControlImplementationTools• Quarterly meterbilling for residential• Monthly meterbilling for highwater uses• Telemetry systems• Field surveys andrepairs• Water audits• Water meters• Hydrant permitsWater Pricing • Sliding tariffs• Wastewater charging• Stormwater chargingWaterEfficientLandscaping/Outdoor UseWater UseAuditsPressureManagement• Education andpromotion• Regulation andrestrictions (e.g. hosepipe restrictions)• Subsidies (e.g. raintanks)• Mandatory auditsfor high water useindustries• Residential wateraudits on request,or as part ofprogramme• Pressure zonemanagementWater Demand ManagementCommentaryProvides for better accountability and enables leaksto be more quickly detected by customers.Enables better tracking of Non Revenue Water lossto enable greater controls.All LNOs and Watercare have leakage managementprogrammes in place. Some programmes are moreproactive than others.Wastewater charging now used by 3 LNOs(through CCOs). Legal clarity required for the otherLNOs to implement wastewater charging underthe LGA. There are specific issues that need to beconsidered for high water users. Staggered ratesalso available.Domestic outdoor water use can be very inefficientand educational campaigns may be effective inraising awareness.Hose pipe restrictions over summer are used byother cities in NZ (e.g. Hamilton).Water use audits can identify inefficiencies andways to improve practices.All LNOs and Watercare have in place pressuremanagement programmes. Some programmes aremore proactive than others.Auckland WaterIndustry Response(some areas only). Note: other LNOs considering wastewatercharging, but waiting for legal clarity in relation toLGA requirements.Rain tank subsidies Note: all LNOs have information on websites inrelation to efficient outdoor water use.Progress to2008WastewaterandStormwaterReuse• Subsidies or rebates(e.g. retrofitting raintanks)• Regulation (e.g.required by resourceconsent)• Best practicePotential examples include:• Industrial (e.g. cooling water or general reuse)• Agriculture (irrigation)• Non potable residential• Groundwater recharge60Final 2008 Strategic Plan – December 2008

ManagementOptionInformationand EducationImplementationTools• Media (television,newspapers,websites)• Billboards• Pamphlets• Household waterauditsWater Demand ManagementCommentaryRecent examples include:• WCC 2006/07 “Water Wiseup” campaigntargeting schools and high water users.• RDC 2006/07 “Every Drop Counts” campaigntargeting householdsAuckland WaterIndustry ResponseAction PlanReviewPromotionof WaterEfficientTechnologiesRegulation andRestrictionsBest PracticeSupplyAugmentation• Subsidies andrebates• Water EfficiencyLabelling (WEL)• Free water efficientdevices (e.g. gizmos)• Retrofitting• Regulation• Bylaws• NZ Building CodeProactive measuresled by water utilities,government and largeindustry.Feasibility studyrequired to identifypotential new watersupply sources, andevaluation processto identify optimumsource.Current examples include:• Rebates offered by NSCC, RDC and WCC forretrofit of rain tanks for non potable wateruse• WEL will be introduced in 2007, and bemandatory for all appliances by 2008.• Free gizmos (or similar) provided by allcouncilsChanges to Building Code could be made tomake water efficient devices mandatory innew developments. Some councils requirenew developments to install rain tanks orgreywater reuse of wastewater or stormwateras part of resource consent conditions.Examples include:• Development of water efficiency plansvoluntarily by industries• Voluntary water audits• Stormwater reuse for irrigation of parks,toilet blocks etcSupply augmentation is a long term strategythat will eventually be required for theAuckland Regions growing population andassociated demand. Most effective if coupledwith other water demand managementinitiatives, as this can delay when additionalsupply required.Key Watercare Metrowater North Shore City Council United Water Waitakere Manukau Water Rodney District Council Franklin Auckland City61Final 2008 Strategic Plan – December 2008

Options fornew sources– north orsouth?Investigations have shown that there are potential newsources of water to both the north and south of Auckland.SocialNorthern• Maintains security of supply for northernparts of the urban area by reducingdependence on harbour bridge crossings.Each brings different attributes to future water sourcemanagement.Southern• Adaptation of network to mitigate riskassociated with bridge crossings throughalternative infrastructure.CulturalEnvironmentalEconomic• Potential concern about developingabstractions and impoundments for intercatchment transfers.• Commitment to major constructionahead of need “just in case”.• Increases the cost of pumping due todistance.• New pipeline route to be found.• Higher cost option.• May require reworking of recentinvestment for Orewa.• Increase of Waikato River abstractioncould be of concern.• Incremental design allows expansion asdemand increases “just in time”• Builds on existing consents andknowledge of environmental impact.• Pipeline corridor already developed.• High energy usage.• Least whole of life cost option.• Increasing energy costs are of concern.Options for northern or southern source and network developmentPotentialFutureSources tothe North ofAucklandWatercare undertook a comprehensive investigation ofalternative regional water sources in 1995. As part of this2008 Strategic Planning Programme a high level reviewof the more favourable options from the 1995 study wasManganui River, at Waiotira confluenceWairoa River, at Manganui confluenceundertaken to update the costs of supplying water fromeach. No work has been undertaken to determine if thesources are still available as land use and ownership mayhave changed over the past 12 years.Manganui River, near TaipuhaHakaru River at TopuniHoteo RiverAraparera RiverMakarau RiverCampbell Road DamRangitopuni Catchment62Kakamatua StreamFinal 2008 Strategic Plan – December 2008

Growth in the region’s demand for water will initially be metby increasing the amount of water taken from the WaikatoRiver to the consented maximum of 150,000 m 3 /d. The riverhas substantial capacity to provide additional water for theAuckland region, if required in the future. An advantage ofthis option is that, unlike a dam, the source can be expandedin stages as demand arises. This has been proven to be verycapital cost effective with the current Waikato plant andmeans that costs can also be staged.Expandingthe WaikatosourceThe Waikato SourceDeveloping different and new water sources and methodsof saving water can be compared to understand which arethe most sustainable and cost effective options. Each ofthe major options that contribute to either the supply ordemand side of the balance has a cost associated with it.Membrane treatment technologyComparing the net present values provides an indicationof the most cost effective of those options.This graph shows that staged development of the Waikatosource is a more cost effective solution than developingother sources to the North of Auckland.Futurewater supplyoptions -comparativecostsMarginal cost of m3 of yield ($)76543210Leakage Management500030000Cost curve showing increasing marginal cost of achieving each successive m 3 of waterWaikato Additional(125, 170, 250 to 340 ml/d)Both northern and southern sources would require anadditional network of pipes to deliver water to Auckland.A comparison between sources and the associatednetworks constructed for 2057 indicates that the southernoption would cost less. Both options offer the same levelAquifier DevelopmentWastewater reuseHoteo RiverAraparera/ makarau River5500080000105000130000155000180000205000230000255000280000305000330000355000380000405000430000455000480000RiverheadYield per day (m)Groundwater rechargewith pre-teatmentWairoaManganui RiverDesalination505000530000555000580000605000630000655000680000705000730000755000780000805000830000SubsidiesRain Tanks855000880000905000of service. Subsidies to encourage purchase of waterefficient appliances would have a greater costthan $7 per m 3 . Energy requirements and reliability ofelectricity supplies will be critical considerations in anyfinal decisions.NetworkManagementis very costeffectiveWaikatoexpansionoffers a costeffectivefuture supply63Final 2008 Strategic Plan – December 2008

Northern andSouthernNetworkrequirementsNorthern Network MapSouthern Network Map64Final 2008 Strategic Plan – December 2008

Option 2057 Network Costs 2057 Source Development Cost TotalSouthern Source $560m $200m $760mNorthern Sources $507m $450m $957mFrom a cost point of view, a southern source is clearly preferred. Prior to making a final choice a further review of northernsources will be undertaken.Network andsource totalcostsThe assumptions listedbelow were used to developa proposed water demandstrategy.The effectiveness of any strategy will depend almostentirely on the willingness and commitment of councilsand local network operators and the regional communityto make the strategy work.The broad assumptions are:• Rain Tanks on all new domestic properties will beinstalled with a projected saving of up to 80,000 m 3 /dby 2100.• Beneficial wastewater use for industrial purposes willstart at 5,000 m 3 /d from 2015 and increase to 20,000m 3 /d by 2025.• Universal wastewater charging will be in place by 2015and result in a saving of approximately 6,000 m 3 /d inwater use.• Pressure and leakage management will result in savingsof around15,000 m 3 /d by 2045. This will require leakagerates to be maintained at 60 litres per connection.• Additional groundwater recharge and/or use willincrease from current levels by 1,000 m 3 /d in 2015,rising to 15,000 m 3 /d by 2025.• Water audits of schools, industry and domestic use willresult in savings of 20,000 m 3 /d from 2015.• The use of water efficient devices will reduce waterdemand by 500 m 3 /d by 2015 and by 23,000 m 3 /dby 2100.• Overall targets are:- 15% reductions in per capita demand by 2025- 10% of supply provided by beneficial use ofstormwater and treated wastewater by 2025.If the above components of the efficiency scenario arefully implemented, the effects on the future water demandforecast for the Auckland region would be to defer thenext major regional water source by around 20 years.Comprehensive cost benefit analysis will be required toconfirm the most appropriate savings target.Developinga 2008 LongTerm WaterEfficiencyScenario65Final 2008 Strategic Plan – December 2008

FutureSupply-DemandEfficiencyimpacts9 50,000The following graph outlines the effect meeting targets on water source requirements. It should be noted that the strategyoutlined is only one of many options for reducing demand. All decisions will need to be subjected to cost/benefit andpublic consultations processes.Auckland Region Water Demand Projection Showing the EffectsWater Efficiency Can Have On Future Water Source Requirements100 MLD FutureSource 2081100 MLD FutureSource 2099850,000100 MLD FutureSource 2062750,000100 MLD FutureSource 2043100 MLD FutureSource 2096m 3 /d650,000100 MLD FutureSource 2026550,000450,000350,000Waikato IA250,0001999200420092014201920242029203420392044204920542059206420692074Waikato IB20792084208920942099Waikato IIWaikato IIAWaikato IIl100 MLD FutureSource 2046100 MLD FutureSource 2070Period of Deferal Approximately 20 YearsYearsRegional demand projection - medium growth senarioRegional demand projection - high growth senarioLocal Network Operators’ demand projectionLong Term ScenarioRegional demand projection - low growth senarioHistoric UseSource Planning LineSource Planning Line AdjustedAll elements of the strategy will require investment, justas the development of a new source would. Reviewingthe possible costs indicates the strategy will be moreexpensive than the development of the next Waikatosource. However, this efficiency cost would have thebenefit of putting off the development by up to 20 years.It is also consistent with an overall philosophy of “reduce,recycle and reuse.Waitakere DamLower Nihotupu Dam Spillway66Final 2008 Strategic Plan – December 2008

Part FStormwater67Final 2008 Strategic Plan – December 2008

Stormwater– our currentsituationStormwater is formed when rainfalls on hard surfaces and is sheddirectly from those surfaces,such as roofs, roads and lowpermeability soils.It generally remains as stormwater for a relatively shorttime while it finds its way into an existing water body suchas a stream, a lake, an estuary or the sea.Without controls, stormwater can cause serious harm tothe environment, by:Zinc (mg/kg)< 124124 - 150> 150Washing silt from land development and building sites intostreams, estuaries and the seaTransporting a wide range of contaminants like zinc intothe environment, resulting in accumulation in sedimentsDamaging areas within overland flow paths and resulting inflooding of houses, industrial and commercial premisesand landMaintenance of stream banks is also an ongoing concernof a number of councils. On the other hand, because itoriginates from rainfall and is formed in large quantitiesin urban areas, where there are large numbers of people,Causing erosion of stream banks at times of high flow,adding to the amount of sediment discharged downstreamand adversely affecting stream ecologystormwater can be used as a local water source.However, unless it is treated, it is only suitable for nondrinking purposes such as toilet flushing, clothes washingor garden watering.Regional Stormwater Action PlanIn 2004, the Boston Consulting Group undertook a reviewof regional stormwater management which became theRegional Stormwater Action Plan. The plan identifiedadditional effort was required in the areas of:• Integrated Catchment Management planning;• Controlling contaminants at source;• Regional communication and community education;• Local authority capacity building; and• Alternative sources of funding.These issues remain relevant and while progress has beenmade, future solutions will continue to require regionallycoordinated efforts in these areas.68Final 2008 Strategic Plan – December 2008

Different stormwater managementopportunities exist in newdevelopment (greenfield areas),compared to largely developedurban (brownfield) areas.In greenfield areas, options exist to manage stormwaterto substantially reduce its adverse effects, provided thenecessary regulatory policy direction is in place andenforced. Ad hoc development of urban areas over manyyears without effective stormwater policy in place meansthat serious stormwater effects are occurring in parts ofthe urban area and mitigation options are constrained byexisting development.In greenfield areas, options include:Stormwatermanagementoptions andresponsibilitiesWater friendly urban designRain gardensWetlandsCapture and useIn brownfield areas, options include:Local solutions to mitigate overland flow and floodingUpgrading existing stormwater treatment devicesStream protection worksRetrofitting storage tanks69Final 2008 Strategic Plan – December 2008

StormwaterregulationandresponsibilitiesActivity Responsible Party Method IssuesResource Management Act – Avoid, remedy or mitigate effects ofstormwater, National Coastal Policy StatementBuilding Act/Code – Control on certain building materials, rules relatingSetting nationalpolicy direction Central Government Statute to gully traps, rules relating to building in flood plains (Controls oncontaminants from cars)Local Government Act – Control of nuisance arising from stormwater, agreelevels of service with affected communitiesSetting regionalpolicy directionApproving worksin accordancewith regionalpolicySetting land usepolicySettinginfrastructuredesign standardsApproving landdevelopmentApprovingbuildingdevelopmentProvidingcommunityinfrastructureProvidingmajor newdevelopmentinfrastructureSmall scaleprivateinfrastructureMaintainingstream banksAuckland RegionalCouncilAuckland RegionalCouncilCity and DistrictCouncilsCity and DistrictCouncils andnetwork operatorsCity and DistrictCouncilsCity and DistrictCouncilsCity and DistrictCouncils, networkoperators andprivate developersLand developersPrivate partiesAdjacent landownersRegional Plan: Air, Landand Water under RMARegional Plan: Coastalunder RMARegional Plan: SedimentControl under RMAResource consentsunder RMA, and takinginto account harbourmodels, fate and effectof contaminants, etcDistrict Plans underRMA and giving effectto the Regional PolicyStatementInfrastructure designstandards manualsLand use or subdivisionconsents under RMABuilding permits underBuilding ActIn accordance withthe Local GovernmentAct and any RMArequirementsIn accordance withRMA and, in particular,any resource consentconditionsAs above and BuildingActRMA and Building ActHealth Act – Protection of public healthFlood managementStream managementEffects of stormwater contaminantsAdoption of the Best Practicable OptionEffects of dischargesStructures in the Coastal Marine AreaControl of sediment from subdivisions, specifically, and from small sites aspermitted activitiesDefines rules for construction, operation, maintenance and monitoringDevelopment locations and densitiesImpermeable area rulesFlood management controlsBuilding close to streamsDefines requirements for infrastructure to be taken over by the networkoperator or CouncilControls development activity and defines monitoring requirements,consistent with the District PlanControls building/development activity and monitoring, and may includesediment control and control on discharges to approved outfalls to controleffects on sensitive environmentsCan be used to mitigate existing effects or facilitate new developmentMust be undertaken in accordance with the relevant infrastructure designstandards manual and conditions acceptable to relevant local council ornetwork operator if it is to be taken over by the council or network operatorAs aboveNeed to maintain stream banks to minimise erosion and allow free passageof water70Movingforward onStormwaterIn general, stormwater needs to bemanaged locally to address localityspecific issues in accordancewith levels of service agreed withcommunities. There are a numberof important areas where regionallyconsistent policy directed towardsminimising future stormwaterproblems would be beneficial.Policy is required in relation to:• Gulley trap design to minimise entry of stormwater intosanitary sewers under flood conditions.• Small site sediment controls.• Management of stormwater from roads, with control oftransport derived contaminants at source, if practicable(requires central government initiatives).• Control of other stormwater contaminants at source.• Rainwater collection and use to reduce effects ofstormwater run-off and provide a source of nonpotablewater.• Overall urban, site and building design guidelines toeliminate poor stormwater design practices.• Definition of areas where further building is restricteduntil existing stormwater problems are addressed.• Infrastructure design standards for both stormwater andwastewater to minimise leakage into and/or out of bothsystems, as appropriate.Through the Three WatersStrategic Plan envisages, theestablishment of a multi partyworking group to address thepolicy issues and communicateoutcomes to the wider regionalcommunity has been facilitated.Final 2008 Strategic Plan – December 2008

Part GStrategicPlanSummary71

Three WatersStrategicPlanSummaryThe Three Waters StrategicPlanning Programme was initiatedin 2004 to ensure the integratedand efficient delivery of watersupply, wastewater and stormwaterservices throughout the Aucklandregion. After more than four yearsof investigations, undertakenjointly by all territorial councilsand network operators in theregion, the Final 2008 StrategicPlan has been prepared forconsideration by regionaldecision-makers.Key proposals set out in the draftStrategic Plan are:To place a strong emphasis on water demand1 management to delay the need to provide a newwater source for up to 20 years, with estimateddeferred expenditure of $300 million;2To reduce the gross per person demand for water by15% of 2004 levels by 2025. An additional 10% oftotal demand will be met by beneficially using treatedwastewater for industrial purposes and rainwaterfor non-potable household purposes over the sameperiod (To be confirmed by cost benefit analysis).3To plan for higher regulatory standards in relation todrinking water and wide-ranging changes to the waywe manage our water supply systems, from source totap;4To secure long-term access to the Waikato Riveras the main future water source for Auckland, butcontinuing to investigate a new northern watersource, increased use of central Auckland aquifersand the use of rain tanks and/or treated wastewateras possible alternative future water sources;5To provide a new central interceptor to augment trunkwastewater sewer capacity as a matter of urgency, toprovide for growth, meet agreed levels of service andsatisfy regulatory requirements;6To ensure continued focus on maintaining and/orenhancing water quality of the Manukau Harbour byoptimising and improving treatment provided by theMangere Wastewater Treatment Plant;7To secure access to a second regional wastewaterfacility at Rosedale for use once the capacity of theMangere Wastewater Treatment Plant is reached;8To manage stormwater locally in accordance withlevels of service agreed with the local community forflood, stream and contaminant management and, inaddition, to develop regionally consistent policy andinfrastructure design and implementation standardsfor a range of issues that affect the delivery of bothstormwater and wastewater services;9To plan future three waters services to reflect theneed to minimise use of and conserve energy, as faras practicable, while still meeting agreed levels ofservice; and10To assess opportunities for efficiencies inresource use and cost savings that can be achievedthrough the joint planning and implementation ofintegrated solutions for the delivery of water supply,wastewater and stormwater services and develop anequitable basis of sharing the benefits achieved.72Final 2008 Strategic Plan – December 2008

Document Status1Final document2Draft requires finalisation3Nearing completion4Supporting documents available• TW 28 Trade Wastes Management 4Note: A number of the reports listed below were prepared byconsultants and, in the case of TW 37, by North Shore City Council.• TW 27 Management of Biosolids 2They are given TW numbers only for reference purposes.• TW 30 Management of Wastewater Liquids –• TW 2 Issues Report, June 2006 1Direct beneficial use opportunities 2• TW 5 Condition of existing surface waterenvironment 2• TW 31 Management of Wastewater Liquids –Indirect Use and Disposal Options 2• TW 6 Strategic overview of the effects of• TW 32 Review of conditions of Manukauthree waters services on the regionalHarbour following Mangere wastewatersurface water environment 2treatment plantupgrade 4• TW 7 Groundwater resources 1• TW 33 Capacity of different receiving• TW 8 Feasibility of treated wastewaterenvironments to accept treatedreinjection into central Auckland isthmuswastewater 2groundwater aquifers 1• TW 34 Mangere wastewater treatment plant• TW 9 Regional growth and implications for– Identification of options for futurethree waters services 1upgrading 1• TW 11 Regulatory requirements 3• TW 35 North Shore City outfall discharge• TW 13 Consultation feedback from previousregime evaluation 1projects of relevance 2• TW 36 Rosedale wastewater treatment plant• TW 14 Kaupapa Maori 1upgrading options 1• TW 15 Options evaluation criteria and process 2• TW 37 Rosedale WWTP Outfall – Report No• TW 18 Water supply demand management 45.06: Innovation Review Report 1• TW 19 Water supply sources issues and options 4 • TW 38 Decentralised wastewater treatment 2• TW 20 Water treatment issues and options 4• TW 40 Evaluation of complete wastewater• TW 21 Water supply network issues and options 4collection, transfer, treatment and use/• TW 22 Wastewater flows and quality –disposal options 2Preliminary report 1• TW 45 Mangere wastewater treatment effluent• TW 23 Inflow and infiltration managementreuse feasibility study 1options 2• TW 46 Basis of Project Costings 1• TW 24 Interim Trunk Wastewater Master Plan– Concept Development and InitialAssessment 1• TW 47 Economic analyses 1• TW 25 Stormwater Issues and Options 2• TW 26 Regional wastewater treatment plantlocations 2Key documentsforming partof StrategicPlanningProgramme73Final 2008 Strategic Plan – December 2008