StormwaterResearchRoadmapforMinnesota

PreparedfortheMinnesotaPollutionControlAgencyandtheCleanWaterLegacyProgram

November2018

Authors:

LawrenceA.BakerandJohnA.Chapman,UMNDepartmentofBioproductsandBiosystemsEngineering

JohnBilotta,UMNExtensionandMinnesotaSeaGrant

ShahramMissaghi,UMNExtension

ProjectLiaison:DavidFairbairn,MinnesotaPollutionControlAgency

ThisworkwassupportedbyMinnesotaCleanWaterLandandLegacyAmendment

fundsallocatedthroughtheMinnesotaPollutionControlAgency.

TheviewsexpressedwithinthisdocumentdonotnecessarilyreflecttheviewsorpoliciesoftheMPCA.

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TABLEOFCONTENTSINTRODUCTION

Theimportanceofurbanlakes 1

Theneedforurbanstormwaterresearch 3

Goalofthisreport 3

APPROACHESUSEDTODISCOVERMINNESOTA’SSTORWWATERRESEARCHNEEDS

Reportandliteraturereview 4

State-widesurveyofstormwaterprofessionalsandpolicyadministrators 4

Policyactorinterviews 6

Focusgroups 6

Interpretationoffindingsandidentificationofresearchneeds 6

RESEARCHNEEDS

#1Improvecharacterizationofurbanstormwaterandwatersheds 8

#2Evaluatetheefficacyofstormwatermanagementpractices atthewatershedscale 11#3Informeffectivepollutionreductionatthesource 13#4ImproveperformanceandreducemaintenanceonstructuralBMPs 15#5Determinethecostefficiencyofstormwaterpractices 19#6Developnewandinnovativestormwatermanagementpractices 21#7Educationtoimprovepublicperceptionofstormwatermanagementandtoimproveeffectivenessofcitizens’actionstoimprovewaterquality 24#8Improvestormwaterstormwatermanagementpolicies 28PRIORITIZATIONOFRESEARCHNEEDS 31FROMRESEARCHROADMAPTOSTORMWATERRESEARCHSTRATEGY 32REFERENCES 34

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APPENDICES1A.MS4Survey:OverviewandDemographicQuestions.1B.Stormwatermanagementsurveysummaryreport.1C.MS4SurveyRawData(Excelfile),postedonprojectwebsite.2.StormwaterResearchNeedsandPrioritizationCriteria:Meetingtheneedsofpolicyactorsandprofessionalstomeeturbancleanwatergoals:AsummaryoffocusgroupsandpolicyactorinterviewsconductedfortheStormwaterResearchRoadmapproject.

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INTRODUCTION

Theimportanceofstormwatermanagement

Urbanstormwater-runofffromlawns,streets,parkinglotsandotherurbansurfaces-isimportant because Minnesotans value their water resources. Urban stormwater is amajorsourceofpollutantstohighlyvaluedurbanwatersandcontributestodownstreampollution of rivers that flow through cities. As urban stormwater flows across thelandscapeitpicksuppollutants.Nutrientssuchasphosphorusandnitrogenareleachedor eroded from vegetated surfaces, contributing to excessive algal growth in lakes andstreams. Erosionofsoilparticles reduceswater c lar ity and contributestothefillingofstormwaterponds,streamchannels,andlakes.Chloridefromwinterde-icingofroadsandparking lotshasbecomeamajorpolluterofbothsurfacewatersand groundwater.Various toxins such as pesticides and other compounds also enter stormwater. Forexample, contaminants from asphalt sealers have contaminated sediments in manystormwaterponds,increasingthecostofsafelydisposingdredgedsediment.

Despiteourruralimage,75%ofMinnesotansliveincitieslargerthan2,500. LakesarefocalpointsforMinnesotacities;someexamplesincludeComoLake(St.Paul)theMinneapolisChainofLakes;AlbertLeaandFountainLakes(AlbertLea);thelakedistrictsofAlexandriaandBrainard;ShagawaLake(Ely);andthemillpondslocatedinmanycitieswithsmallriversflowingthroughthem.

ComoLakeinSt.Paulisapopularattractionforfamilies,walkersandjoggers.

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Remarkably,51%ofMinnesotan’slivewithinamileofanurbanlakeandmanypeopleidentifyclosenesstohomeasamajorfactorforrecreationonthelakestheyusemost(Andersonetal.1998).

PercentageofMinnesotanslivingwithinonemileofanurbanlake.MapdevelopedbyKateCarlson,U-Spatial,OfficeoftheVicePresidentforResearch.

Yetmanyurbanwatersarepolluted. MPCA’slistofimpairedwatersfortheseven-countyMetroregionincludes369waterqualityimpairments,whichmeansthatthesewaterbodiesdonotmeetwaterqualitystandards,andgenerallyrequirescleanup. ThepollutantsthatcausemostwaterqualityimpairmentsforMetroregionwatersarenutrients(184waters),mercuryinfish(140waters),andchloride(22waters). Urbanrunoffisamajorcontributorofnutrientsandchloride,butmostmercuryenterslakesby

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atmosphericdeposition.

Urbanrunoffalsopotentialaffects1.4millionMinnesotanswhogettheircommunitywatersupplies(includingdrinkingwater)fromrivers.Forexample,surfacewatersuppliesforSt.Paul,MinneapolisandSt.Cloudareaffectedbyurbanrunofffrom64upstreamcities.Inadditiontosurfacewaterimpairment,infiltrationofurbanrunoffmaytransportsolublepollutantstogroundwater. AparticularconcernisrisinglevelsofchlorideinshallowgroundwaterintheMetroRegion,probablycausedbyroadde-icingoperations.

Theneedforurbanstormwaterresearch

Therearefivekeyreasonsthatdevelopingacoordinatedstormwaterresearchstrategycouldreduceurbanstormwaterpollution.

1. TherearemanyimpairedurbanwatersinMinnesotathatreceivemuchoftheirpollutionfromstormwater.

2. ThecostofmeetingCleanWatergoalsisveryhigh-estimatedtobe$317millionperyear(BarrEngineering,2017).

3. Thereisaperceptionamongstormwaterprofessionals(documentedlaterinthisreport)thatcurrentstormwatermanagementisnotasefficaciousasitcouldbe.

4. PastresearchinMinnesotatoimproveurbanstormwatermanagementhasresultedintheimplementationofimprovedstormwatermanagementpractices.

5. Futureresearchwouldbeevenmoreproductivebecauseitwouldbeinformedbyourconstantlyimprovingcapacitytoacquire,store,andprocessinformationandbecauseitwillbuilduponlessonslearnedfrompreviousresearchandimplementation.

TheMinnesotaCitiesStormwaterCoalitionsummarizedthesethoughtsinalettertotheMinnesotaCleanWaterCouncilin2018:

“Urbanstormwaterisstillarelativelynewfieldandwehavehugeandimportantgapsinourknowledgeandunderstanding.”

Goalofthisreport

Withthisbackground,thegoaloftheStormwaterResearchRoadmapistoarticulatemajorresearchneedstoimprovestormwatermanagementinMinnesota.

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APPROACHESUSEDTODISCOVERMINNESOTA’s STORMWATERRESEARCHNEEDS

MultiplesourcesandapproacheswereusedtoidentifystormwaterresearchneedsforMinnesota,includingareviewofrelevantstormwater-relateddocuments,andstate-widesurveyofstormwatermanagers,focusgroups,andpolicyactorinterviews.

Reportand literaturereview

Numerousreportsandpublicationsprovidedafoundationforthe inquiry:

Ø StormwaterResearchinMinnesota( interimreport,2017)-this includedinterpretationsand summariesofmultiplesurveysandpublished literature

Ø Governor’sWaterSummitReport (2016)

Ø 2015MinnesotaEQBWaterPolicyReport

Ø MinnesotaWater Sustainability Framework (2010)

Ø Rainfall-to-Runoff:TheFutureofStormwater -WaterEnvironmentalFoundation(2015)

Ø WaterReuseWorkshopProceedingsReport -FreshwaterSociety (2016)

Ø Andmanyothers

State-widesurveyof stormwaterprofessionalsandpolicyadministrators

Asurveywasadministeredto480stormwaterpractitioners,professionals,andpolicyadministrators acrossMinnesota. Thesurveylistincludedthemaincontactsforthefollowing:

Ø MunicipalSeparateStormSewerSystems (MS4)permittees

Ø WatershedManagementOrganizations

Ø WatershedDistricts

Ø SoilWaterConservationDistricts

Ø CountyWaterPlanners

Thesurveyincludedaseriesofmultiple-choicequestionswithopportunitiesforadditionalwritten responsesandcomments.Questionsweredevelopedaroundseventhemespreviouslyusedinthe 2017 interim report:

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Ø SourceReductionandPollutionPrevention

Ø CharacterizationofStormwaterRunoff

Ø ImpactsofSurfaceandGroundwater

Ø Treatment Practice Effectiveness

Ø Maintenance, Longevity, and Cost/Benefit

Ø PublicPolicyandEducation

Ø EmergingConcerns

Thesurveyincludedaseriesofquestionsofincreasingspecificitytotriangulateresearchneedsin eachmajortopicarea.Forexample,weaskedquestionsaboutspecificpollutants,barriersand opportunitiesregardingstormwatermanagement,sourcesofstormwater,andtheextentof development inthe jurisdictionsofrespondents,aswellasspecificquestionsregardingresearch needs.Thesurveywasweb-basedandadministeredbytheMinnesotaCenterforSurveyResearch. 150responses(31%responserate)camefromallpartsofthestate,asshowninthegraphicbelow.MoresurveydetailsarepresentedinAppendixA1andtabulatedresponsesarepresentedinAppendixA2.

Distributionof survey respondents throughoutMinnesota.

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Policy actor interviews

Five interviewswithexperiencedstormwaterprofessionals fromacrossMinnesotaprovided clearerunderstandingofresearchneedsexpressedinthesurveys,focusgroupsandprior researchpublications.Thestormwatermanagers interviewedroutinelyestablishpolicy, fund research,and relyonresearchtoplan,design,andimplementstormwatermanagementatalocalorstatelevel. They included:

Ø Anadministrator fromawatershed jointpowersorganization

Ø Anadministrator fromanot-for-profitorganization

Ø TwoMS4citystormwaterengineers

Ø Astormwaterengineerfromaprivateconsultingfirm

Semi-structuredinterviewsusedaseriesofquestionsprovidedtoparticipants inadvance. The questionscenteredon the following:

Ø Askinghownewresearchorinformationcouldbeusefultothemorthecommunitiestheyworkwithtoprevent,minimize,oroptimizemitigation fromurbanstormwaterrunoff

Ø Discussionsofbothstructuralandnon-structuralpracticesandtheirneedformoreresearchor newinformation

Ø Gatheringopinionstoprioritizecriteriaforresearch

Thesemi-structured formatallowed for flexibleconversationaboutstormwaterresearchneedsusing thepre-determinedquestionsasa foundation. The interviewsandconversationsprovidedan opportunitytogatheradditionaldetailsaboutspecificneedsortopicsraisedinthesurveyandfocus groups.

The interviews were transcribed into electronic documents for qualitative analysis byresearchers. The analysis sorted and coded conversations, looking for themes offrequent responses,multiple citations of priorities, and other ideas about research orinformation needed to advance stormwater management. A report articulating theinterview methods, information obtained, analysis and findings are presented inAppendix2.

Focus groups

Seven focusgroupsorganized in threeworkshopsprovided information fromspecificstakeholder groups. Theworkshopsandfocusgroups included:

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Ø Workshop1 included27staffandprofessionals fromtheMinnesotaPollutionControlAgency working inthestormwater,waterquality,andwaterpolicyprogramareas.

Ø Workshop2had four focusgroups including representatives fromMinnesotacities,watersheds, counties,not-for-profits,andprivateengineers. Thisworkshopused theMinnesotaErosion ControlAssociationandtheMinnesotaCitiesStormwaterCoalitiontosolicitparticipationby20 individuals.

Ø Workshop3 includedtwofocusgroupswithtenresearchersandprofessionalsinvolvedin stormwaterresearchand localstormwatermanagementaffiliatedwiththeUniversityof Minnesota-Duluth.

Thefocusgroupsgenerallycenteredconversationaroundaseriesofquestionsthatincluded:

Ø Identifyingexistingbarriersandopportunities for stormwatermanagement

Ø Identificationofspecific researchneedstoadvancestormwatermanagementideasregardingbarriers and opportunities previously identified

Ø Includeddiscussion, identificationofandrankingofcriteriatoprioritizeneeds.

Informationgleanedfromthesequestionandanswerconversationswasrecordedonpaperand thentranscribed intoelectronicdocumentsforqualitativeanalysisbyresearchers. Similartothe interviews,theanalysissortedandcodedthewritteninformationfromthefocusgroup.Frequently repeatedresponses,multiplecitationsofpriorities,andother ideasaboutresearchor information neededtoadvancestormwatermanagementwerenoted (Appendix2).

Interpretationof findingsand identificationof researchneeds

Identificationofstormwaterresearchneedswas inferredfrombothquantitativedata(surveyresponses)andqualitativedata(focusgroupsandpolicyactorinterviews).Eachofthefollowingeight researchneeds includessupportingevidence fromourfindings.

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ResearchNeed#1: ImproveCharacterizationOfUrbanStormwaterAndWatersheds.

Managingurbanstormwatereffectivelyrequiresgoodcharacterizationofbothstormwaterrunoffandthewatershed. Characterizationofstormwaterincludesmeasurementsofflowandchemicalcharacteristicsatmultiplepointsinawatershedandatvarioustimes,fromminutes(foranalysisofindividualrunoffevents)toyears(toanalyzetrendsinpollutants).Characterizationofwatershedsalsoincludesanalysisoflandscapecharacteristics,suchasmappingfine-scalelandcovercharacteristics(trees,rooftops,andstreets),anddelineatingtheflowpathsofurbanrunoffasitmovestowardstormdrains.Researchcouldalsomakecharacterizationlessexpensive.

Supportingevidence:

1.Most(88%)ofsurveyrespondentsperceivedthatfinancialconstraintswereamoderateormajorbarrierregardingstormwatercharacterization,suggestingthatlessexpensivecharacterizationtoolswouldbeanimportantresearchgoal.

2.Avarietyofresearchtopicswereconsideredimportantorveryimportantbysurveyrespondents,withmorethan50%ofrespondentsratingthemofmoderateoragreatdealof importance:

Ø Sourcesandimpactsofnon-regulatedcontaminants(71%)

Ø Characterizationofrunofffromspecificlanduses(68%)

Ø Toxicityofpondsediments(68%)

Ø Identificationofsourcesofconventionalpollutants(53%).

3.Whenthenaskedfortheirtopresearchpriority,characterizationofrunofffromspecificlanduseswasselectedby35%,followedbytoxicityofpondsediments(28%).

4.Researchneedsaroundcharacterizationalsoincludedadvancedmonitoringmethodsstormwaterrunoff,suchasreal-timeanalysis.

Asonewatersheddistrictmanagernoted:

“Somereallygoodguidanceaboutmonitoring, methodologythatcouldworkbetter.Thatcouldbevaluable,...couldextendresources.IthinkthathassomeappealbecausethenIfeelbetteraboutwherewe'respendingourtime.ThenperhapstheUniversitycouldusesomeofourdata.”

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Discussion:

ImprovedcharacterizationofurbanwatershedsandstormwaterqualitycouldhelpstormwatermanagersimprovetheeffectivenessofBMPswhilealsoloweringthecostofcharacterization,especiallystormwatermonitoring. Ourrapidlyexpandingtechnologicalcapacitytoacquire,storeandanalyzewaterqualitydatamakescontinuousimprovementofcharacterizationactivitiesfeasible.AdvancesindataacquisitiontechnologiesinMinnesotaincludestate-wideLiDARmapping (whichprovidesveryfine-scaleelevationmaps)anddevelopmentofLiDAR-enabledfine-scale (0.6m)landcovermapping.Thesenewdatatoolsenableresearchersdevelopnewtoolsforstormwaterandwatershedcharacterizationthatwouldhavebeenimpossibleadecadeago.Newcharacterizationtoolscouldcollectwaterqualitydataatfinelypinpointedtimesandplaces,enablingmoreprecisetargetingofstormwatermanagementactivities.

Anexampleofnewcharacterizationtools:Finescalelandcovermapping,downto2x2footpixels,enabledresearcherstomaptreecovercanopythroughtheCapitalRegionWatershedDistrict,makingitpossibletomapinputsofphosphorusfromvegetativedebrisfortheentirewatershed.

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Advancesinwatershedlandscapecharacterizationwouldcreateopportunitiestoimprovespatialtargetingofstormwatermanagement. Forexample,findingsfromtwostudiesattheUMN-oneresultinginafine-scalemapoflandcovercharacteristics(includingindividualtrees) andtheotherresultinginamodelofnutrientremovalbystreetsweeping-werecombinedtoquantifyinputsofnutrientsfromvegetativedebrisontostreetsacrosswatershedsintheCapitalRegionWatershedDistrict.

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ResearchNeed#2: EvaluateTheEfficacyOfStormwaterManagementPracticesAtTheWatershedScale.

Ultimately,thegoalofstormwatermanagementistoimprovethequalityofreceivingwaters(lakes,streams,andgroundwater)atreasonablecost.AlthoughweknowthepollutantremovalforagivenBMP,weneedbetterknowledgeregardingchangesinwaterqualityinlargerurbanwatersheds,whichmaycontaindozensofBMPsandalsobeaffectedbychanginglanduseandotherfactors.

Supportingevidence:

1. Ofthoseresponding,37%ratedtheirMS4programseffectivenessinimprovingsurfacewaterqualityatashighorveryhigh;54%ratedeffectivenessasmoderate,and9%gavealowrating.

2.Weaskedsurveyrespondentstoratefourresearchtopicsregardingqualityofreceivingwaters.Allfourtopics-trendsinsolublepollutants(suchasnitrate&chloride)ingroundwater, trendsinconventionalpollutants insurfacewaters, trendsinbiologicalindicators,anddevelopmentofnewmetrics,suchas‘ecosystembenefits’,expressedineconomicterms,were ratedassomewhatorveryimportantby81%to94% ofrespondents.

3.Whenaskedwhichsingleissueshouldbethehighestresearchpriority,50%selectedtrends inconventionalpollutants,and9%to24%selectedoneoftheotherthreetopics.

4.Anewreportestimatesthecostoffuturestormwatermanagementtobe$317millionperyear(BarrEngineering2018). InthecontextofResearchNeed#2,theissueiswatershed-scalecostsin relationtowatershed-scalewaterqualityimprovement. Costefficiencyisdiscussedlaterinthe contextofindividualBMPs(ResearchNeed#5).

5.A2014MetCouncilwaterqualitystudyofMetroregionstreamsconcluded:

“Trendresultsindicateimprovementsinwaterqualityinthemajorityofmonitoredstreamsduring2008-2012basedonreductionsinsediment,phosphorus,andnitrateflow-adjusted concentrations.However,thetrendanalysisdoesnotidentifywhichactions,projects,structures,orpracticeshavecausedtheimprovements(ordeclines).”

Ontheotherhand,chloridetrendshaveoftenbeenincreasinginMetroregionstreams,lakes,andgroundwater(MPCA2017).

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Discussion:

Wenowhaveawealthofmonitoringdataonurbanlakesandstreams,especiallyintheMetro regionthatcouldbeusedtoevaluatebothtrendsinwaterqualityandthemultipledriversthatcausethesechanges,includingspecificstormwatermanagementpractices,landuse/landcoverchanges,thelawnphosphorusfertilizerlaw,etc. Someurbanstreamshavebeenmonitoredconsistentlyfor20yearsormoreandwenowhavesatellite-inferredlakeclaritydatadating backto1975. However,analysisofthesedatabaseshasbeenlimited,especiallywithrespecttoassigningcausesofwaterqualitychanges.

Researchtoevaluatefuturewatershed-scaleeffectivenessofstormwatermanagementwillbenefitfromtheimplementationof“InternetofThings”–networksofinexpensiveground-basedandremotesensingsystemsthatwillfacilitateanalysisofwaterqualitytrendsandtheunderlyingmechanismsthatcausethesetrends,includingstormwatermanagement.

MapoftotalphosphoruslevelsintheMetroregion. Mostwatershaveshownslightdeclines,butthereasonisn’twellknown. Source:MCES2014.

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ResearchNeed#3.InformEffectivePollutionReductionAtTheSource.

Sourcereduction,alsocalledpollutionprevention,meansreducingtheproductionofpollutantsfromthewatershedbeforetheybecomepartofthestormwaterrunoffstream.Sourcereductionalsoincludesreducingthevolumeandrateofstormwaterrunoff.

Treeleavesaccumulatinginacatchbasin.

Supportingevidence:

1.Whensurveyrespondentswereaskedaboutpotentialopportunitiesforimprovingstormwatermanagement,75%ratedwideruseofpollutionprevention/sourcereductionasamoderateormajoropportunity.

2.InabilitytoreducesourcesofTMDLpollutantswasidentifiedasamoderateormajorbarrier towardsimprovedstormwatermanagementby64%ofsurveyrespondents.

3.Morethan60%ofrespondentsidentifiedsuspendedsolids,phosphorus,chloride,andnitrogenashavingmoderateormajoropportunityforreductionbysourcereduction/pollutionprevention.

4.Whenaskedspecificallyaboutbarrierstopollutionprevention/sourcereductionBMPs,ratingsofsomewhatorveryimportantwere:

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Ø Practicalbarriersforimplementation(94%)

Ø Perceivedlowpotentialforimprovingwaterquality(78%)

Ø Lowpublicacceptance(69%)

Ø Lackoftechnicalknowledge(74%)

Ø Regulatoryrequirements(69%)

Ø Lowadministrativesupport(62%)

5.Focusgroupsandpolicyactorinterviewsalsoexpressedaneedformoreinformationandresearchrelatedtopollutionpreventionandsourcereductionpractices.Researchneedscenteredaroundthedesireformoreinformationabouttheeffectivenessofpollutionpreventionpractices,howmuchcreditforreductionshouldbegiventothesepractices,andhowcost-effectivepollutionpreventioniscomparedwithothertypesofpractices.

Onepolicyactorexpressedtheneedforadditionalresearchinthisareabysaying:

“Beforeitisthestormsewer.Imeansourcereduction.Whatarethesourcesofpollutantsthatwecanknockout. Thatsortofthing.Wehavespentalotoftimeonwhatwecanputontheendof thestormwaterpipetomakeitbetter...butI'dliketoknowmoreaboutwhatwecandobeforeitentersthepipe.”

Discussion

Sourcereductionhasbeensuccessfulforreducinginputsofpollutantstostormwater,whichshouldmotivatefutureresearch.Someexamplesinclude:

Ø Anestimated90%reductioninstormwaterleadconcentrations,accomplishedbyreductionsofleadingasolineandpaint(Bakeretal.2008).

Ø EvidencesuggestingthatMinnesota’slawnPfertilizerlawhasreducedphosphorusinlakes(Halbach2016).

Ø Aproductbanoncoaltar-derivedasphaltsealants,whichwillprobablyreducePAHsinstormwaterpondsediments(Mahleretal.2012)

Ø Eliminationofvariousorganochlorinechemicalsinthe1970s,resultinginmajorreductionsofthesecompoundsinfishtissues(Schmidttetal.1990)

Recentresearchdemonstratesproperlytimedstreetsweepingmaybeaverycost-efficientway toremovenutrientsfromstreetswithsubstantialtreecanopy(Kalinoskyetal.2013). Source reductionistheonlyfeasiblewaytoreducechloridecontamination,

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andresearchmayyieldwaystodothisveryefficiently. Reducinginputsofcoarsesolidstostormwatercatchbasinsmayalsobeaneffectivewaytoimprovepondmaintenance,whichisanimportantbarriertostormwatermanagementinMinnesota(seeResearchNeed#5).

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ResearchNeed#4. ImprovePerformanceAndReduceMaintenanceOnStructuralBMPs.

StructuralBMPsincludestormwaterponds,drydetentionbasins,infiltrationbasins,wetlands,raingardens,swalesandrelatedpracticesthattrapandfiltersedimentsandsediment-boundpollutantsandmayreducetherateand/orvolumeofstormwaterrunoff.

Dredgedpondsedimentsbeingde-wateredinlargefilterbags

makeiteasiertotransportthesedimentstoalandfill.

Supportingevidence:

1. Inoursurvey,financialconstraintsandlong-termmaintenancewereidentifiedasmoderate ormajorbarriersregardingtheeffectivenessofstructuralBMPsby83%and82%ofrespondents,muchhigherthanotherbarriers. Thetwoissuesarerelated,becausemaintenancecanbeexpensive.

2.WhenaskedspecificallyaboutresearchneedsforBMPs,long-termmaintenanceandperformanceofwidelyusedBMPswereratedassomewhatorveryimportantby89%and95%ofrespondents,respectively.(OtherBMPresearchneedsarediscussedinResearchNeeds#5and#6).Surveyresponsescreateastrongcaseforadditionalresearchofoperationandmaintenancestormwaterpractices. Inmanycases,multiplefocusgroupsandinterviewparticipantselevatedtheseconcernsespeciallyrelatedtospecificpractices.

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3. Weobservedstrongimpressionsinfocusgroupsandpolicyactorinterviewsthatpondmaintenanceisimportant. Asonecityengineernoted:

“…wehavetobecleaningourpondsout.Iknowit'svery,veryexpensive.That'sanothergoodone.Researchneed.Howcanwemakeponddredgingcheaper?Canwegetvolumedown?Isitaboutstrategicdredging?

…Therearepondsthathaven'tbeenmaintainedfor40yearsandwe'recountingonthese.”

4.Otherscommentedonlong-termmaintenanceoftherelativelynewpracticeofusingundergroundfiltrationsystemsandonbioretentionsystems. Oneengineercommented:

“ThisundergroundsystemIhaveiscompletelycloggedeventhoughImaintainedit.Itwouldnotdrain.WhatdoIdonow?”

Apolicyactorfromanongovernmentalorganizationcommented:

“Idon'tknowhowlongawellmaintainedraingardenlasts.Idon'tknowhowlongacrappymaintainedraingardenlasts.Whathappensifweletitgotocrapandsuddenlyit’stakenoverbyundesirableplants.Therearevariationsofthosequestionswedon'tknowtheoutcomefor.”

Andawatershedorganizationadministratorcommented:

“Whatisthetypicallifespanofabioretentionbasinbeforeyouhavetodigitup?Canyoureallyleaveitalonefor10yearsoris therestuffyouhavetobedoing.”

Vacuumtrucksremovesedimentfromacatchbasin.

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Discussion:

PollutantremovalratesforcommonBMPsarewell-documentedbutremovalratesareoftenlowandvariable(Weissetal.2008).Newresearchtoimprovepollutantremovalperformancemight includestudiesofstormwatersolidscharacteristics,theprocessesbywhichpollutantsareremoved,andwinterperformance,whichispoorlyunderstood.

Inaddition,researchtoreducemaintenancerequirementsofBMPsmightincludestudiesofforebaystotrapcoarsematerial,improveddredginganddewatering,andsourcereductionofsolids.

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ResearchNeed#5. DetermineTheCostEfficiencyOfStormwaterPractices.

Thecostofstormwatermanagementincludesbothcapitalcosts(forexample,theconstructionofstructuralBMPs)andoperationandmaintenance(O&M). ExamplesofO&McostsareremovalofaccumulatedsedimentsanddebrisandotheractionstomaintaintheeffectivenessofBMPs.ForsomeBMPs,theO&Mcostscanexceed50%ofcapitalcosts.

Comparisonofcapitalcostsandoperationsandmaintenance(O&M)costsforseveralBMPsintheCapitalRegionWatershedDistrict(CRWSD2012).Costsaresometimes

calculatedasdollarsperpoundofpollutantremoved.

Supportingevidence:

1.Ninety-sixpercentofsurveyrespondentsratedcostsandbenefitsofindividualBMPs asbeingamoderateormajorresearchneed.

2.Whenaskedtorank13researchneedsrelatedtobothcommonlyusedandinnovative

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practices,costsandbenefitsofindividualBMPswererankedasthetoppriorityby19%ofrespondents,justbelownew,innovativeBMPs.(ResearchNeed#6).

4.Therecentestimationofstormwatermanagementstatewidecostsof$317millionperyear(BarrEngineering2017)highlightstheneedforimprovedcostefficiency.

5.Researchoncostefficiency,normalizedtouniversalmetricslike$/lbpollutantremovedforeachBMPor$/acreofdrainagearea,wouldenablestormwatermanagerstomakemorecostefficientchoices.

6.Participantsinfocusgroupsandpolicyactorinterviewsexpressedtheirneedforinformationusingavarietyoftermsincludingcost-benefit,cost-effectiveness,life-cyclecostsandpollutantremovalefficiency. Often,theyusedthesetermsinterchangeably.

“Ithinkthereisadefiniteneedforsomeonetodosomelegitimatelifecyclecostsanalysis.”…“Whatisthetruecostwhenwearebuildingitnowversusthewaywecouldbuildit?Butnobodyhasreallypulledthatstuff[economicdata]togetherreallywellandthecityengineersandpublicworksdirectorsouttherewouldlovetohavethatsowouldthewatersheddistricts.”saidaNGOpolicyactor,asentimentechoedrepeatedlyinthefocusgroupsandpolicyleaderinterviews.

Discussion:

Researchonstormwatermanagementpracticecostsandbenefitsshouldthereforehavetwo thrusts.First,therewasconsiderableinterestinreducing-termoperationsandmaintenance (O&M)costs,especiallyforstormwaterponds,whichneedtobeperiodicallydredgedtoremovesediments. ResearchtopicsmightincludeimprovedP8modeling,sourcereductionBMPstoreducesolidsinputstoponds,betterdesignofforebaystotrapcoarsesediments,andmethodstomanagedredgedsediment,especiallywhentheyarecontaminatedwithtoxinssuchasPAHs(polyaromatichydrocarbons,whichcomefromasphaltsealers,combustion,andothersources).

Asecondresearchthrustmightbeside-by-sidecomparisonsofthecostsandbenefitsofindividualstructuralandnon-structuralBMPsandnon-structuralpracticessuchassourcereduction. FindingswouldenablestormwatermanagerstoselectthemostcostefficientBMPs.

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ResearchNeed#6. DevelopNewAndInnovativeStormwaterManagementPractices.

CurrentBMPsoftenhavelimitationssuchashighcosts,variabletreatmenteffectiveness,largelandrequirements,andaccumulationofpollutants.Becauseofthis,thereisconsiderableinterestinemergingBMPsthatreducetheseproblems.Newknowledgeonsourcereductionandinnovativepollutiontreatmentcanquicklycreateopportunitiestoimprovestormwatermanagement.

Supportingevidence:

1.Sixty-fivepercentofsurveyrespondentsratedimproveddesignandmaintenanceofstructuralBestManagementPracticesasbeingmoderateormajoropportunitiesinwaterqualityimprovement.

2.Forty-ninepercentofsurveyrespondentsratedavailabilityofsuitablesitesforstructuralBMPsasamoderateormajorbarrier.

3.WhenaskedspecificallyaboutresearchonBMPs,designandperformanceofnew,innovativeBMPsratedassomewhatorveryimportantby90%ofrespondents. Onthesamequestion,designandperformanceofBMPsforconstrainedspacesratedassomewhatorveryimportantby88%ofrespondents.

4.Whenthequestionwasnarrowedfurther,askingrespondentstorankresearchneedsforemergingpractices(highorveryhighimportance),thefourtoprankingswere:

Ø Stormwaterreuse(59%)

Ø Enhancedfiltrationsystems(49%)

Ø Treesforhydrologiccontrol(43%)

Ø Enhancedstreetsweepingfornutrientremoval(42%)

5.WhenaskedtopickthesinglemostimportanttopicforBMPresearchamongbothemergingandcommonpractices,designandperformanceofnewinnovativeBMPsrankedfirst,selected20%ofthetime.

6.FocusgroupandpolicyactorinterviewparticipantsmostfrequentlyexpressedthefollowingareasfornewresearchonemergingBMPs:

Ø Stormwaterreusesystems

Ø Iron-enhancedsandfilterpractices

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Ø Practicesthatusetrees

Ø Alternativestotheuseofchlorideforwinterdeicing

Somecommentsfromfocusgroups:

“Researchonthedifferenttypesofsystemsusedtotreatreusewaterisneeded.”

Acitystormwaterengineer:

“Treetrenches. They'rebecomingmorepopular,butIdon'tthinkwereallyknowexactlyhowmuchvaluetheyareadding….Therecouldbesomerealvalueinresearchonthis. Itwillneedtobelongterm.Compareandcontrastthesesystemsthataresupportingtrees.”

Aprivateengineer:

“Ohhere'sanotherresearchneed,takesomeoftheseironenhancedfiltersthataren'tworking.Itwouldbeinterestingtohaveaplaybook.It'saveryhottopicrightnow.Alotofpeopleareworkingonthese.Whyaretheresomeironenhancedfiltersworkingandsomethatarefailing. Howtodesignthemforoptimalconditions. Afilterthathasbeendesignedbyyouorsomeoneelse,howdoyoufixit?Doyoureallyjusthavetorebuildit?Oristhereawaytoreplenishthesystems.Howdoyoufixthem?Howtoretrofittheretrofit?”

RainwaterfromtheroofoftheMetroTransitOperationandMaintenanceFacilityfortheGreenLineLRTiscollectedina27,000-galloncisternforuseinCHSFieldirrigationandtoiletflushing,saving450,000gallonsofwaterand$1,600peryear.

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Discussion:

TherewasstronginterestinresearchtodevelopandunderstandemergingBMPs. Nooneemergingpracticestoodout,butthetopicofstormwaterreusehasattractedwideattentionandisbeingimplementedatdozensofsitesthroughoutMinnesota.Theconcernhereistheimpactofreusedwateronhumanhealth.

TheissueofBMPsforbuilt-upareasmaybecomemoreimportantbecausedensificationof innerurbanareaswillcontinue,limitingspaceavailableforstructuralBMPs.

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ResearchNeed#7. EducationToImprovePublicPerceptionOfStormwaterManagementAndToImproveEffectivenessOfCitizens’ActionsToImproveWaterQuality.

Stormwatereducationbringspublicawarenessandbehavioralchangesthatreducewatercontaminationandminimizenegativeenvironmentalimpactsofexcessivestormwaterrunoff.Stormwatereducationisofferedtostormwaterprofessionals(training),thepublic(schooleducation,citizeneducation),andpublicofficials. Stormwatereducationresearchareasinclude investigatingtheneedsandtheefficacyofstormwatereducation(principles,concepts,andmethods).

Stormwaterprofessionalsconductingawaterqualitypondinspectionfieldexerciseaspartofthe2018SWU:StormwaterPracticesMaintenanceCertificationWorkshop.

SupportingEvidence:

1.Minnesotastormwaterprofessionalsandpolicyactorsratedstormwatereducationandtrainingasthesecondhigheststormwaterresearchneedandthethirdhighestbarrierto improvingwaterquality.

2.Surveyrespondentsrankededucationandtrainingasthethirdhighestopportunitytoward improvingwaterquality,with70%ratingthistopicasamoderateormajoropportunity.

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3.Publiccooperationandsupportidentifiedasthethirdhighestbarriertowardsimprovingwaterqualityintheirjurisdictions,with62%ofrespondentsratingthistopicasamoderateormajoropportunity.

4. Conversely,threetopicswereratedasmoderateormajorbarrierstowardstormwatereducationbymorethanhalfofrespondents:

Ø Insufficientfunds(64%)

Ø Lackofinterest(63%)

Ø Lackofmeasurementforeducationeffectiveness(62%)

5. Withregardtoresearchonstormwatereducation,allsixtopicspresentedrankedwereconsideredhelpfulorveryhelpfulbylargemajorities:

Ø Effectivenessofeducationtoelicitbehaviorchange(89%)

Ø Effectivenessofeducationaboutimprovingwaterquality(87%)

Ø Evaluationmethodsforeducationandcommunicationtools(87%)

Ø Effectivenessofeducationeffortstoincreaseknowledge(85%

Ø Effectivenessofeducationtoimprovewaterquality(87%)

Ø Methodstoincreasepublicoradministrativesupportforeducationefforts(81%)

Themostimportanttopicidentifiedbysurveyrespondentswaseffectivenessofeducationtoelicitbehaviorchange,selectedby43%(eachoftheothertopicswererankedmostimportantbylessthan20%ofrespondents).

6. Finally,whenaskedaboutvalueofnewinformationandresearchtovariousaudiences,eachchoicewasratedasveryorsomewhatimportantbymorethan90%ofrespondents:

Ø Localelectedandappointedleaders(92%)

Ø Homeownersandrenters(92%)

Ø Businessownersandemployees(93%)

Ø Stormwaterprofessionals(93%)

Ø Youth(inbothK-12andinformalenvironments)(90%)

Ø Socialorganizations(gardenclubs,lakeassociations,etc.)(90%)

Twotopicsweremostcommonlyratedasthetoppriorityforeducationresearch:educationtoelicitbehaviorchange(selectedby43%ofsurveyrespondents)andeffectivenesstoimprovewaterquality(selectedby19%)

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7. Focusgroupparticipantsidentifiedstormwatereducationandtrainingasthesecondhigheststormwaterresearchneed. Similartothesurveyfindings,thefocusgroupparticipantsidentifiededucatingaudienceswithspecificpriorities,themosteffectiveeducationpracticestoreachthoseaudiences,andmeasuringtheeffectivenessofeducationeffortsasresearchneeds.

Acitystormwaterengineerstated:

“Researchisneededonwhatactivatespeople.Whatmotivatespeopleincludingwhatwouldmotivatecitystafftodomoreeducation?Whatmotivatesresidentstodosomethingintheiryards? Whatwillmakealakecabinownerquitmowingtotheedge?”

Thesecondresearchneedinstormwatereducationwasbetterknowledgeoftheeffectivenessofvariouseducationandbehaviorchangestrategiesandwhereitcanhelpustoshowthat...hoursspentoneducationrelatestophosphorusremoval. Theresearchneedsto investigatetheefficacyofstormwatereducationwasreiteratedduringtheNGOpolicyactorinterviewsbystatementssuchas:

“Icantellyouhowmuchphosphorusagrassswalecanremove,buthowmanypoundsofphosphoruswilltalkingtothreecabinownersremove?”

Discussion:

OnecommonthemeallfocusgroupsandthesurveyfoundwastheneedforresearchonhowbesttomotivateallMinnesotanstobebettercleanwaterstewards. Minnesotahasadiversepopulationofpeoplewhomaynotsharethesamevocabularytoarticulatetheirhopes,expectations,andintendeduseoftheirnaturalresources. Researchisneededonhowtoexpandtheaudienceofstormwatereducation,includevoicesofallpeople,andengageallMinnesotans. Thisresearchmighthavetwoveins. First,educationcouldfocusonchangingattitudestowardstormwatermanagementandincreasingpublicsupport,whichisoftenlacking. Thismayleadtopublicacceptanceofincreasedfundingforstormwatermanagementactivities,orstrengthenedlocalstormwaterordinances.

Second,educationcaninformdirectactionbycitizens.Ofparticularvaluewouldbequantificationoftherelationshipbetweenbehaviorchangeandwaterquality.Educationfocimightincludede-icingpracticesonprivateproperty,lawnmanagementpractices,treeleafmanagement,andremovalofpetwastefrom landscapes.

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ResearchNeed#8:ImproveStormwaterManagementPolicies.

Beyondengineeringresearch,policyresearchcouldstrengthenstormwatermanagement.Policyresearchexaminesissuessuchaseffectiveness,economics,equity,andaccountabilityofexistingandalternativepolicies.

Supportingevidence:

1.Severalmoderatetomajorpolicy-relatedbarriersthatmightbereducedbyresearchinclude insufficientfundingtofullyimplementBMPsidentifiedinTotalMaximumDailyLoad(TMDL)plans(79%ofrespondents),levelofpubliccooperationand support(62%),andineffectiveregulations(45%).

2.ImprovedCleanWaterpolicybeyondtheMS4programwasidentifiedasamoderateormajoropportunityby62%ofsurveyrespondents.

3.SeveralquestionsregardingpolicyissuesfortheMS4programsintheirjurisdictionalsosuggestsseveralpolicy-relatedopportunities.

Ø EffectivenessoftheirlocalMS4programsatimprovingsurfacewaterqualitywasratedmoderate,low,orverylowby54%ofrespondents

Ø CostefficiencyoftheirMS4programswasratedasmoderate,low,orverylowby72%

Ø SenseofunnecessaryregulatoryburdenoftheMS4programwasratedashighorveryhighby59%

4.Whenaskedtorankalistofpotentialpolicy-relatedresearchissues,allwerehighlyrankedas somewhatorveryimportant,withrankingsfrom78%(pollutiontrading)to95%(costeffectivenessofBMPs).

Ø EvaluationofcostsandbenefitsofspecificBMPs(95%)

Ø Evaluationofstate-wideeffectivenessoftheMS4programforachievingimprovedwaterquality(89%)

Ø Adaptivemanagement(forexample,greaterflexibility,useofnonconventionalBMPs,successbasedonmeasuredwaterqualityimprovement)withintheMS4program(85%)

Ø Improvedintegrationofstormwatermanagementandfloodcontrolpolicies(83%)

Ø Efficacyofstormwatereducation(83%)

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Ø Astudyofpollutiontradingfornutrientremovalacrosscitiesandfarmland(78%).

5. Whenaskedtoidentifythehighestpriorityforpolicyresearch,evaluationofcostsandbenefitsofspecificBMPswasmostcommon (38%ofrespondents). Amongothertopics,thetopprioritychoicewasfairlyevenlydistributed:

Ø EvaluationofstatewideeffectivenessoftheMS4programforachievingimprovedwaterquality(18%)

Ø Adaptivemanagement(forexample,greaterflexibility,useofnonconventionalBMPs,successbasedonmeasuredwaterqualityimprovement)withintheMS4program(15%)

Ø Astudyofpollutiontradingfornutrientremovalacrosscitiesandfarmland(12%)

Ø Improvedintegrationofstormwatermanagementandfloodcontrolpolicies(9%)

Ø Efficacyofstormwatereducation(8%)

Severalpolicyactorcommentshighlightpolicyresearchquestions:

“Aretherulesthatweadopted,forexampleMIDSoruseofundergrounddevices,leadingustoaplacewherethesethingsaregoingtobearealpaininthefuture?Didthepolicyworkoutinthewaythatwehadthought?” (Privatestormwaterengineer)

ParticipantsinfocusgroupsandinterviewsalsoexpressedtheneedforresearchonpolicyissuesrelatedtostructuralBMPs. Additionalresearchcouldaddressconcernsforsomeofthemorerecentpracticessuchasthefateofpollutantsandthebelow-groundoperationsofreusesystems. “Researchonrulesandregulationsforreusewouldbecritical,”citedoneprivateengineer.

Discussion:

Supportingevidencerevealsaperceptionamongstormwaterprofessionalsthatstormwatermanagementistooexpensiveandthepublicdoesnotunderstandbenefits.

OneofthetopresearchissuesidentifiedistheeconomicsofstormwatermanagementatthelevelofMS4jurisdictionsandatthewatershedscale,andatleastimplicitly,atthestatelevel.

Economicsresearchmightevaluatepollutiontradingbetweenurbanrunoffandagriculturalrunoff,asstreamsenteringcities(especiallyinruralMinnesota)oftencontainrunofffromagriculturalland,whichmaycontributesubstantiallytourbanwater

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pollution. Inthissituation,theregulatedentities(cities,throughtheMS4programs)mightbewillingtopayforreductionofagriculturalpollution(whichisnotsimilarlyregulated),iftheoverallcostofmeetingaregulatorygoalwaslowerthanrelyingsolelyonmanagementofurbanrunoff.

UrbanlakeslikeAlbertLeaLakecanbeatriskfromwaterenteringfromagriculturalareastreamscarryingsedimentandfertilizers.

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PRIORITIZATIONOFRESEARCHNEEDS

Weaskedstormwaterprofessionalstoprioritizeurbanwaterresearchneedsthroughsurveys,focusgroups,andpolicyactorinterviews.Acrossresearchtopics,wefoundthefourmostimportantcriteriaforrankingresearchneedswere:

Ø Effectivenessandreliability

Ø Numberofpeopleaffected

Ø Applicability

Ø Cost

Theapplicabilitycriteriawereexpressedasmoreplaces,ormorepractices,ormorepeople. Costincludedboththecostoftheresearchandthecostsavingsresultingfromresearchfindings.Whenappliedtoresearchonbehaviorchange,applicabilitymayconsiderthenumberofpeopleandtherangeofpopulationaffected. Forresearchonnewtreatmenttechnology, applicabilitymayconsiderthenumberofdifferentplacesorsituationswherethetechnologycouldbeimplemented.

Criteriathatwerenotashighlyrankedacrosstopicsweredepthofunderstanding,urgency, andactionability.

Wesuggestthatfundingsponsorsusethefourhighestrankedcriteriatoinformprioritiesforresearchandintheevaluationofresearchproposals.

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FROMRESEARCHROADMAPTOSTORMWATERRESEARCHSTRATEGY

Theprevioussectionsoutlinedarationale foradditional researchonstormwatermanagement, eightspecificresearchneeds,andevaluationcriteriaforresearchideas.Hereweelucidatetenets tocompleteaStormwaterResearchRoadmap:

Focusoncleanwatergoals.Thecentralframingstatementthatemergesfromstakeholdersisthat astormwaterresearchstrategyshould focuson improvingtheeffectivenessofstormwater managementtowardthegoalofachievingcleanwater,withgreatercostefficiency.

Anadaptiveresearchstrategy. AviableStormwaterResearchRoadmapmustbeadaptive.WesuggestthatthisResearchRoadmapbeupdatedeveryfiveyears,inconcertwiththeCleanWaterLegacy’sfive-yearplanningcycle.AgoalmightbetointegrateresearchfindingsfromthepastfiveyearsintotheCWLnewpolicyandpracticesforthenextfiveyears,whileincorporatinganupdatedResearchRoadmaptomeetknowledgeneedsforthenewplanningperiod.

Convergenceofwaterqualityprograms.Increasingly,waterqualityprograms,suchastheMS4,TMDL,andOneWaterprogramsareconverging.Newresearchcouldsynergizethisconvergence.

Coordinationof resources.Theformationof theStormwaterResearchCouncil (SRC)attheUniversityofMinnesota’sWaterResourcesCenterprovidesa coordinatingbodyforpotentialresearchsponsors. Funnelingfundsintooneunit is administrativelyefficientandthecompositionof theSRC(includingstormwater expertsoutside theUniversity) assures thoroughandunbiased recommendations for funding stormwaterprojects.

Need forpartners.Partnershipsbetween researchersandcities,watersheddistricts,individuals, companies,non-profits, andotherorganizationsare important . Thesepartnershipsarealso importanttodirect researchfunding. Localpartneringwithuniversityresearchersresults inshareddata,accesstofield sites,anddirectparticipationbya jurisdiction’sstaff.

Translationtopractice. Stormwaterpractitionersoftenfeel thatuniversityresearchfindingsdonotgettranslatedintopractice. Solutionsmightincludelongergrantcycles(typicallytwo-threeyearsnow)that includeatranslationalphase(e.g.,thedevelopmentandtestingofmodelsdeveloped inresearch)andexpandedoutreachand education components,suchasinformingtheMIDScalculatorandtheMPCAStormwaterManual.

Expandedvision. ImprovedengineeredBMPsalonewillnotcleanupurbanwaters.

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Research isneeded fornon-structuralpractices, includingsource reductionpracticesandeducation,andbringingmanagementofnon-regulatedpollutionsourcesi n l i ne w i th u rban s to rmwater goa l s .

TheMinnesotaStormwaterResearchCouncil,CleanWaterCouncil,theUniversityofMinnesotaWaterResourcesCenter,andMPCAarewellpositionedtocreateaformalresearchstrategyfollowingtheframeworkabove.

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