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Delta Nutrients
Drinking Water Issues
FINAL White Paper
Prepared for:
Delta Nutrient Science and Research Program
Stakeholder and Technical Advisory Group
June 20, 2017
DeltaNutrients–DrinkingWaterIssues i June20,2017
Acknowledgements
ThewhitepaperistheresultofastakeholdergroupeffortbytheDeltaNutrientDrinkingWaterWorkgroup.Participantsinthisgroupinclude:
ElaineArchibald,ArchibaldConsulting
LyndaSmith,MetropolitanWaterDistrictofSouthernCalifornia
TerrieMitchell,SacramentoRegionalCountySanitationDistrict
LysaVoight,SacramentoRegionalCountySanitationDistrict
DebbieWebster,CentralValleyCleanWaterAssociation
KyleEricson,CityofSacramento
TonyPirondini,CityofVacaville
JenniferClary,CleanWaterAction
AndriaVentura,CleanWaterAction
MikeWackman,DeltaAgriculturalCoalition
ChrisFoe,CentralValleyRegionalWaterQualityControlBoard
ChristineJoab,CentralValleyRegionalWaterQualityControlBoard
JanisCooke,CentralValleyRegionalWaterQualityControlBoard
TomGrovhoug,LarryWalkerAssociates
BrianLaurenson,LarryWalkerAssociates
MikeTrouchon,LarryWalkerAssociates
RachelPisor,CaliforniaDepartmentofWaterResources
DeltaNutrients–DrinkingWaterIssues ii June20,2017
DeltaNutrients–DrinkingWaterIssues iii June20,2017
Executive Summary
TheSacramento–SanJoaquinRiverDelta(Delta)isakeycomponentofCalifornia’swaterresourcesystemandservesasanimportantsourceofdrinkingwatertoover25millionCalifornians.However,issuesassociatedwithinvasivemacrophyteandcyanobacteriagrowthhavebeenincreasingoverthelastdecadeaddingsignificantconcernassociatedwithinfrastructureclogging,tasteandodorissues,andrisingcyanotoxinconcentrations.Bothmacrophyteandcyanobacteriagrowthareaffectedbyconcentrationsofthenutrientsnitrogenandphosphoruswhicharerequiredfortheirgrowth.However,theconnectionbetweennutrientsandinvasivemacrophytesandharmfulcyanobacteriaiscomplexandremainsanactiveareaofstudy.Thisdocumentprovidesasynthesisofthecurrentstateofknowledgeregardingnutrient‐relateddrinkingwaterissuesintheDeltaanddownstreamconveyanceandstoragefacilities,andpresentsasetofrecommendationstoaddressdatagapsinmonitoring,research,andmodelinginordertosupportpolicydecisionsonnutrientmanagement.
TheCentralValleyRegionalWaterQualityControlBoard(CentralValleyWaterBoard)andstakeholdershaveinvestedsignificantresourcesintounderstandingthesciencebehindtheseissuesinordertomakesound,science‐basednutrientmanagementpolicydecisionsinthefuture.TheyhaverecentlycompletedthefollowingWhitePaperswhichservedasafoundationfortheresearchsummarizedinthisdocument:
CyanobacteriaWhitePaperandKnowledgeGapDocument MacrophyteWhitePaperandKnowledgeGapDocument ModelingWhitePaper
AllofthesedocumentscanbefoundontheCentralValleyWaterBoardwebsiteundertheScienceWorkGroupssection:www.waterboards.ca.gov/centralvalley/water_issues/delta_water_quality/delta_nutrient_research_plan/science_work_groups/index.shtml.
ARoleofNutrientsinShiftsinPhytoplanktonAbundanceandSpeciesCompositionintheSacramento‐SanJoaquinDeltaWhitePaper(a.k.a.FormsandRatiosWhitePaper)wasrecentlyreleasedthatdiscussestheroleofnutrientformsandratiosintheDelta.However,duetoitsrecentsubmittal,itscontentswerenotsummarizedinthisdocument.WeencourageinterestedreaderswhowanttoknowmoreabouttheseparticularissuestoreadtheotherassociatedWhitePapers.
ThisdocumentprovidesasynthesisofthecurrentstateoftheknowledgeregardingnutrientsintheDelta,highlightstheuniquenutrient‐relateddrinkingwaterqualityissuesfacedbytheDeltaandwatersupplyproviders,exploresfactorswhichinfluencemacrophyteandcyanobacteriagrowth,presentsmanagementoptionstodealwiththeseissues,andidentifiesdatagapswhichrequireadditionalresearchandmonitoring.Themainnutrient‐relateddrinkingwaterissuesidentifiedinclude:
Tasteandodorissuesduetocyanobacteriagrowth, Cyanotoxinreleasebyharmfulcyanobacteriablooms,and
DeltaNutrients–DrinkingWaterIssues iv June20,2017
Filterand/orpumpcloggingbymacrophytesandalgae. Section6.0ofthisdocumentsynthesizestheinformationpresentedinprevioussectionsandoutlinesasetofrecommendationsforadditionalmonitoring,research,andmodelingpriorities.Highlightsoftheserecommendationsincludethefollowing:1. Cyanobacteria–Cyanotoxins:Expandsystem‐widemonitoringintheDeltaanddownstreamfacilitiesinordertoidentifythelocation,timing,anddurationofcyanotoxin‐producingcyanobacteriabloomsandthethreatthatcyanotoxinspose.Determineviafieldandlaboratorystudiesifancillarybiological(e.g.,chlorophylla),chemical(e.g.,nutrients),orphysical(e.g.,temperature,irradiance,flow)measurementsco‐varywithbloomssuchthattheycouldbeusedtopredict,limitinitiation,and/ormanagedurationofcyanobacterialblooms.
2. Cyanobacteria–TasteandOdors:Expandsystem‐widemonitoringindownstreamfacilitiesinordertoidentifythelocation,timing,anddurationoftasteandodorcyanobacteriaevents.MeasureasuiteofenvironmentalparametersincludinggeosminandMIB(thecompoundsresponsiblefortasteandodorevents),nutrients,andperformmicrobialsurveysinordertoexpandknowledgeofpossibledriversoftasteandodorevents.Determineviafield(includinginsituormesocosmstudies)andlaboratorystudiesifancillarybiological(e.g.,specificbenthicorplanktonicspecies),chemical(e.g.,nutrients),orphysical(e.g.,temperature,irradiance,flow)measurementsco‐varyorcontributetotasteandodorinitiationandattenuation.
3. Macrophytes:Expandsystem‐widemonitoringintheDeltaanddownstreamfacilitiesinordertodeterminetheabundanceandextentofinvasivemacrophyteblooms(includingnewinvasivespecies)aswellasanyco‐occurringenvironmentalparametersthatmightcontributetotheirgrowth,andtodeterminewheremacrophytebloomsareimpactingoperationsofwatersupplyfacilities.Performfieldandlaboratorystudiestodeterminemacrophytegrowthrateasafunctionofnutrientconcentrations,includingnutrientuptakerates,andpossiblemethodsforinsituassessmentofnutrientlimitation.Conductinsitustudiestotesttheeffectnutrientlimitationmayhaveontheenhancementofmechanicalandchemicalmacrophytecontrol.
4. ModelingScenarios:Utilizemodelstocharacterizeandtestmanagementactionsoverarangeofconditions,provideinsightintothesignificanceofnutrientsontheecosystem,andcommunicateinformationtostakeholders,regulators,andresourcemanagerstoarriveatconsensusandunderstandingofthesystem.
5. ManagementConsiderations:Oncemonitoringandmodelingeffortshavematured,theseeffortsshouldbeusedtoaddressthequestionofwhethernutrientreductionsaloneorinsomecombinationwithothermanagementpracticeswillbeeffectivetosignificantlyreducetasteandodor,cyanotoxinissues,andfilter/pumpcloggingproblemsintheDeltaanddownstreamfacilities.
DeltaNutrients–DrinkingWaterIssues v June20,2017
Table of Contents
Acknowledgements........................................................................................................................................i
ExecutiveSummary.....................................................................................................................................iii
ListofTables................................................................................................................................................viii
ListofFigures...............................................................................................................................................viii
1.0Introduction,Purpose,andOrganizationoftheReview...........................................................1
1.1BackgroundandContext.....................................................................................................................................1
1.2GoalandOrganizationofDrinkingWaterIssuesLiteratureReview................................................2
2.0Nutrient‐RelatedDrinkingWaterIssues........................................................................................5
2.1DeltaNutrientsBackground...............................................................................................................................5
2.1.1DeltaHydrology................................................................................................................................................5
2.1.2TheStateWaterProject................................................................................................................................5
2.1.3ContraCostaWaterDistrict.........................................................................................................................7
2.1.4NutrientConcentrationsintheDeltaandSWP...................................................................................8
2.2ProblemsAssociatedwithHighNutrientLevelsandotherEnvironmentalFactors................13
2.3AlgaeandMacrophyteProblemsinDrinkingwaterSupplies...........................................................13
2.3.1NuisanceAlgaeandHarmfulCyanobacteriaBlooms......................................................................13
2.3.2Macrophytes....................................................................................................................................................30
3.0FactorsInfluencingNutrient‐RelatedDrinkingWaterIssues.............................................32
3.1Light/SolarIrradiance........................................................................................................................................32
3.2Waterclarity...........................................................................................................................................................33
3.3Temperature...........................................................................................................................................................33
3.4Residencetime/flow...........................................................................................................................................34
3.5Salinity.......................................................................................................................................................................35
3.6Nutrientconcentrationsandratios...............................................................................................................35
3.7Dissolvedinorganiccarbon..............................................................................................................................36
DeltaNutrients–DrinkingWaterIssues vi June20,2017
4.0ManagementofIdentifiedIssues....................................................................................................37
4.1Managementoptions...........................................................................................................................................37
4.1.1NutrientLoadManagement.......................................................................................................................37
Cyanobacteria.............................................................................................................................................................38
Macrophytes...............................................................................................................................................................38
4.1.2Harvesting(macrophytes).........................................................................................................................38
4.1.3BiologicalControl(macrophytes)...........................................................................................................39
4.1.4ChemicalAdditions(e.g.coppersulfate,etc.fornuisancealgalblooms,tasteandodorepisodes)..............................................................................................................................................................39
5.0DataGaps.................................................................................................................................................40
5.1PrevalenceofProblemsintheDeltaandDownstreamConveyanceandStorageFacilities..40
5.2Spatialandseasonaloccurrenceofproblems...........................................................................................41
5.3Effectivenessofalternativemanagementoptionsonspecificproblems......................................41
5.4Monitoringdataandprocesscoefficients/parametersrequiredforecosystemandmanagementmodels...........................................................................................................................................42
6.0RecommendationsforMonitoring,ResearchandModelingPriorities............................43
6.1Problemdefinition...............................................................................................................................................43
6.2Roleofnutrientsincombinationwithotherfactors..............................................................................43
Cyanobacteria–Cyanotoxins...............................................................................................................................43
Cyanobacteria–TasteandOdors.......................................................................................................................44
Macrophytes...............................................................................................................................................................45
6.3Modelingtoolsandscenarios..........................................................................................................................46
DevelopmentofModelingTools.........................................................................................................................46
ModelingScenarios..................................................................................................................................................47
6.4Effectivenessofmanagement..........................................................................................................................48
7.0LiteratureCited.....................................................................................................................................49
AppendixA.....................................................................................................................................................58
DeltaNutrients–DrinkingWaterIssues vii June20,2017
A.1THESTATEWATERPROJECT.........................................................................................................................58
A.2NutrientConcentrationsintheDeltaandSWP.......................................................................................70
A.3CyanobacteriaTaxaMakeup............................................................................................................................76
A.4PotentialAlgalProductionofSourceWaters...........................................................................................77
DeltaNutrients–DrinkingWaterIssues viii June20,2017
List of Tables
Table1.StateWaterProjectFacilitiesandTargetOrganismsAddressedbytheCaliforniaDepartmentofWaterResourcesAquaticWeedandAlgalBloomControlPrograms(DWR2013)................................................................................................................................................................................19
Table2.USEPAAlgalToxin10‐DayDrinkingWaterHeathAdvisories(applicabletotapwater).....24
Table3.MicrocystisBiomassandMicrocystinConcentrationsinCliftonCourtForebay........................25
Table4.USEPAD/DBPRuleRequirementsforTOCRemoval...........................................................................29
List of Figures
Figure1.TheSacramento‐SanJoaquinDeltaandSWPMonitoringLocations..............................................4
Figure2.TheStateWaterProject.....................................................................................................................................6
Figure3.ContraCostaWaterDistrictDeltaWaterIntakes...................................................................................9
Figure4.TotalNConcentrationsintheSWPWatershed:2004–2010.........................................................11
Figure5.TotalPConcentrationsintheSWPWatershed:2004–2010..........................................................11
Figure6.TotalKjeldahlNitrogenandTotalPhosphorusatOldRiverIntake:2010–2014..................12
Figure7.TotalKjeldahlNitrogenandTotalPhosphorusatMiddleRiverIntake:2010–2014..........12
Figure8.MIBandGeosminConcentrationsatBanksPumpingPlant.............................................................16
Figure9.MIBandGeosminConcentrationsatCheck41ontheCaliforniaAqueduct..............................16
Figure10.MIBandGeosminConcentrationsatCheck66ontheCaliforniaAqueduct...........................17
Figure11.GeosminConcentrationsatCastaicLakeOutlet.................................................................................17
Figure12.MIBConcentrationsatCastaicLakeOutlet...........................................................................................18
Figure13.MIBandGeosminConcentrationsatLakeSilverwoodOutlet......................................................18
Figure14.MIBandGeosminConcentrationsatLakePerrisOutlet.................................................................19
Figure15.GeosminandMIBinContraCostaCanalatClyde:2010–2014..................................................21
Figure16.GeosmininMallardReservoir:2010–2014........................................................................................21
Figure17.MIBinMallardReservoir:2010–2014.................................................................................................22
DeltaNutrients–DrinkingWaterIssues ix June20,2017
Figure18.AlgalBiomassintheSouthBayAqueductatDelValleCheck7....................................................23
Figure19.TotalMicrocystininBarkerSlough..........................................................................................................26
Figure20.TotalMicrocystininCliftonCourtForebay...........................................................................................26
Figure21.TotalMicrocystininBanksPumpingPlant...........................................................................................26
Figure22.TotalMicrocystininDyerReservoir........................................................................................................26
Figure23.TotalMicrocystininLakeDelValleCheck............................................................................................27
Figure24.TotalMicrocystininSanLuisReservoiratPachecointake............................................................27
Figure25.TotalMicrocystininSanLuisReservoiratGianelliIntake.............................................................27
Figure26.TotalMicrocystininO’NeillForebayOutlet.........................................................................................27
Figure27.TotalMicrocystininPyramidLake...........................................................................................................28
Figure28.TotalMicrocystininCastaicLake.............................................................................................................28
Figure29.TotalMicrocystininLakeSilverwood.....................................................................................................28
Figure30.TotalCylindrospermopsininPerrisLake..............................................................................................28
Figure31.pHlevelsinSouthBayAqueductduring2016....................................................................................31
DeltaNutrients–DrinkingWaterIssues x June20,2017
DeltaNutrients–DrinkingWaterIssues 1 June20,2017
1.0 Introduction, Purpose, and Organization of the Review
1.1 BACKGROUND AND CONTEXT
TheSacramento–SanJoaquinRiverDelta(Delta)isanetworkofnaturalandengineeredchannelsandagriculturallowlandslocatedinNorthernCalifornia,formedbytheconfluenceoftheSacramentoandSanJoaquinRivers(seeFigure1).TheDeltaisacomponentoftheSanFranciscoEstuarysystemandisinfluencedbythetides,tovaryingdegrees,throughoutitsdomain.TheDeltaisakeycomponentoftheState’swaterresourcesystem;waterexportedfromtheDeltaservesmorethan25millionpeopleand4.5millionacresofirrigatedfarmlandsintheBayArea,theSanJoaquinValley,andSouthernCalifornia(DeltaStewardshipCouncil2013).Onaverage,approximately6.1millionacrefeet(MAF)ofwaterareexportedfromtheDeltaduringwetyearsandabout4.1MAFduringdryyears(DeltaStewardshipCouncil2013).TheCaliforniaStateWaterProject(SWP)andtheFederalCentralValleyProject(CVP)conveywaterfromtheSouthDeltatotheSanFranciscoBayArea,SanJoaquinValley,CentralCoast,andSouthernCalifornia.Additionally,theDeltaisvitalforthestate’seconomyandenvironmentasahometothousandsofresidentsaswellasanimportantagriculturalareaandacriticalhabitatforfish,birds,andwildlife.
TheDeltaiswidelyrecognizedasbeinginastateof“crisis”duetothecompetinganthropogenicdemandsforitsresources(DeltaPlan2013).TheDelta’swaterresourcesareneededforecosystemhealth,agriculture,fisheries,andmunicipalsupplies.Theconsequencesofthesecompetingdemandsincludehabitatdegradation,fragmentationandloss,highlymodifiedflowregimesandwaterlossesandwaterqualityimpairments,andnon‐nativespeciesinvasions.ThedischargeofpollutantstotheDeltaandtributarywatersfromurban,agricultural,andnonpointsourcesalsoposespotentialthreatstothemanybeneficialusesdesignatedfortheDelta.
In2009,theCalifornialegislaturepassedtheDeltaReformActcreatingtheDeltaStewardshipCouncil(Council).ThemissionoftheCouncilistoimplementthecoequalgoalsoftheReformActandprovideamorereliablewatersupplyforCaliforniawhileprotecting,restoring,andenhancingtheDeltaecosystem.TheCouncilwroteandadoptedaDeltaPlanin2013toimplementthesecoequalgoalswhichincludedawaterqualityrecommendationtoconsiderdevelopmentofnutrientobjectivesfortheDelta(WQR8.CompletionofRegulatoryProcesses,Research,andMonitoringforWaterQualityImprovement).NutrientsareamongthepollutantsdischargedtotheDeltafrommunicipal,industrial,agricultural,andothernonpointsources.ThisrecommendationaddressestheexcessnutrientsintheDeltathatareaprimaryconcernbecausethey,alongwithotherfactors,stimulatemacrophytegrowthandalgalbloomswhichcandisruptwatertreatmentprocesses,causetasteandodorproblems,andcontributetocyanotoxinproduction(DeltaStewardshipCouncil2013).AsnutrientsareoneofthepollutantgroupsbelievedtopotentiallycauseimpairmentstoDeltawaterquality,theStateWaterResourcesControlBoardandtheSanFranciscoBayandCentralValleyRegionalWaterQualityControlBoardshavebeenchargedwithdevelopingandimplementingaresearchplantodeterminetheneedforeithernumericornarrativenutrientwaterqualityobjectivesfortheDeltaandSuisunMarsh.
DeltaNutrients–DrinkingWaterIssues 2 June20,2017
InresponsetotherecommendationintheDeltaPlan,theCentralValleyRegionalWaterQualityControlBoard(CentralValleyWaterBoard)hasembarkedonaDeltaNutrientResearchProgramtoaddresstheneedfornutrientwaterqualityobjectives.Inordertoprovideappropriatebackgroundregardingthecurrentunderstandingandknowledgegapsassociatedwithspecificnutrient‐relatedareasofinterest,andtoinformtheneedforfutureresearchintheDelta,workgroupswereformedwithlocalexpertleadershiptodevelopwhitepapersandrecommendationsforfutureresearchneedsonthefollowingtopics:
Cyanobacteria Macrophytes NutrientFormsandRatios DrinkingWaterConcerns ModelingScience
1.2 GOAL AND ORGANIZATION OF DRINKING WATER ISSUES LITERATURE REVIEW
ThisdocumentprovidesasynthesisofliteratureonthepotentialadverseimpactsofambientnutrientlevelsintheDeltaondrinkingwatersourcesintheDeltaandtheSWP.Asameanstogaininsightintothenutrient‐relatedissuesencounteredinout‐of‐Deltaconveyancestructures,reservoirs,andwatertreatmentfacilities,aworkshop1ontastesandodors,cyanobacteria,macrophytes,andotherfactorswasheldtoinformtheDrinkingWaterWorkgroupontheseissues.TheworkshoppresentersincludedcurrentandformeremployeesoftheMetropolitanWaterDistrictwhospecializeinunderstandingandattemptingtolimitalgaeandmacrophytebloomsthatimpactdrinkingwaterintheSWPanddownstreamreservoirs.Thisdocumentidentifiesdatagapswithinthecurrentbodyofknowledge,andsuggestsstudiesthatwouldprovideinformationtobridgethosegaps.Theliteraturereviewhasthreemajorobjectives:
1. ProvideabasicreviewofdrinkingwaterissuespresentintheDeltapotentiallyassociatedwithcurrentnutrientlevels;
2. ProvideadiscussionofassociatedimpactstoCalifornia’sdrinkingwaterresources,bothwithintheDeltaandindownstreamconveyanceandstoragefacilities;and
3. IdentifydatagapsandresearchneedstounderstandwhethercontrolofnutrientconcentrationsintheDeltawouldreduceexistingdrinkingwaterconcerns.
Thisreview,andtherecommendednextsteps,willcontributetotheDeltaNutrientsScienceandResearchPlanwhichwillidentifyscientificresearchneededtodeterminewhetherandhowtoproceedwiththedevelopmentofnutrientwaterqualityobjectivesfortheDelta.Thedocumentisorganizedasfollows:
1WorkshoptoIdentifyResearchProposals–TastesandOdors,Cyanobacteria,Macrophytes,andOtherFactors.WorkshopheldonFebruary24,2017,attheofficesofLarryWalkerAssociates,Davis,CA.
DeltaNutrients–DrinkingWaterIssues 3 June20,2017
Section1:Introduction,Purpose,andOrganizationoftheReview
Section2:Nutrient‐RelatedDrinkingWaterIssues
Section3:FactorsInfluencingNutrient‐RelatedDrinkingWaterIssues
Section4:ManagementofIdentifiedIssues
Section5:DataGaps
Section6:RecommendationsforResearchandModelingPriorities
Section7:LiteratureCited
DeltaNutrients–DrinkingWaterIssues 4 June20,2017
Figure 1. The Sacramento-San Joaquin Delta and SWP Monitoring Locations
DeltaNutrients–DrinkingWaterIssues 5 June20,2017
2.0 Nutrient-Related Drinking Water Issues
2.1 DELTA NUTRIENTS BACKGROUND
2.1.1 Delta Hydrology
ThetwomajorsourcesoffreshwaterinflowtotheDeltaaretheSacramentoandSanJoaquinRivers(seeFigure1).Additionalflowscomefromtheeastsidetributaries:theMokelumne,Calaveras,andCosumnesRivers.TheSacramentoRiverprovidesapproximately75to85percentofthefreshwaterflowtotheDeltaandtheSanJoaquinRiverprovidesabout10to15percentoftheflow.Duringextremelywetyears,SacramentoRiverflowscanexceed100,000cubicfeetpersecond(cfs)atFreeport.TheflowsintheSanJoaquinRiveratVernalisaresubstantiallylowerthanflowsintheSacramentoRiver.PeakSanJoaquinRiverflowscanexceed50,000cfs,butflowsarenormallymuchlower.FlowsontheSacramentoandSanJoaquinriversarehighlymanaged.CentralValleyProject(CVP)andSWPreservoirsontheriversandtheirtributariesattenuatethehighlyvariablenaturalflows,capturinghighvolumeflowsduringshortwinterandspringperiodsandreleasingwaterthroughouttheyear.
WaterfromtheSacramentoRiverflowsintothecentralDeltaviaGeorgianaSloughandtheDeltaCrossChannel,whichconnectstheSacramentoRivertotheMokelumneRiverviaSnodgrassSlough(seeFigure1).TheDeltaCrossChannel(DCC)isoperatedbytheU.S.BureauofReclamation(Reclamation).TheDCCoperationsareregulatedtomeetmultipleneeds,includingfishmigration,Deltawaterquality,floodprotection,andflowintheSacramentoRiver.TheDCCisgenerallyclosedbetweenJanuaryandmid‐June,openbetweenmid‐JuneandOctober,andclosedinNovemberandDecember.FlowsofSacramentoRiverwaterthroughtheDCCimprovecentralDeltawaterqualitybyincreasingtheflowofhigherquality(lowersalinity,lowerorganiccarbon)SacramentoRiverwaterintothecentralandsouthernDelta.TherelativeimpactoftheDCCoperationsonwaterqualityatthesouthDeltapumpingplantsisgovernedbywaterprojectoperations,tidalaction,andflowsontheSanJoaquinRiver.
2.1.2 The State Water Project
TheSWPextendsfromthemountainsofPlumasCountyintheFeatherRiverwatershedtoLakePerrisinRiversideCounty.Figure2showsthemajorfeaturesoftheSWP.WaterfromthenorthDeltaispumpedintotheNorthBayAqueduct(NBA)attheBarkerSloughPumpingPlant.BarkerSloughisatidallyinfluenceddead‐endsloughwhichistributarytoLindseySlough.LindseySloughistributarytotheSacramentoRiver.ThepumpingplantdrawswaterfromboththeupstreamBarkerSloughwatershedandfromtheSacramentoRiver,viaLindseySlough.TheNBAservesasamunicipalwatersupplysourceforanumberofmunicipalitiesinSolanoandNapacounties.
InthesouthernDelta,waterentersSWPfacilitiesatCliftonCourtForebay(CliftonCourt),andflowsacrosstheforebayabout3milestotheH.O.BanksDeltaPumpingPlant(Banks),fromwhichthewaterflowssouthwardintheGovernorEdmundG.BrownCaliforniaAqueduct(CaliforniaAqueduct).WaterisdivertedintotheSouthBayAqueduct(SBA)atBethanyReservoir,1.2miles
DeltaNutrients–DrinkingWaterIssues 6 June20,2017
Figure 2. The State Water Project
DeltaNutrients–DrinkingWaterIssues 7 June20,2017
downstreamfromBanks.FromBethanyReservoir,waterflowsintheCaliforniaAqueductabout59milestoO’NeillForebay.TheforebayisthestartoftheSanLuisJoint‐UseFacilities,whichservebothSWPandfederalCVPcustomers.CVPwaterispumpedintoO’NeillForebayfromtheDelta‐MendotaCanal(DMC).TheDMCconveyswaterfromtheC.W.“Bill”JonesPumpingPlant(Jones)to,andbeyond,O’NeillForebay.SanLuisReservoirisconnectedtoO’NeillForebaythroughanintakechannellocatedonthesouthwestsideoftheforebay.AnintakeonthewestsideofthereservoirprovidesdrinkingwatersuppliestoSantaClaraValleyWaterDistrict.
WaterreleasedfromSanLuisReservoirco‐minglesinO’NeillForebaywithwaterdeliveredtotheforebaybytheCaliforniaAqueductandtheDMC,andexitstheforebayatO’NeillForebayOutlet,locatedonthesoutheastsideoftheforebay.O’NeillForebayOutletisthebeginningoftheSanLuisCanalreachoftheCaliforniaAqueduct.TheSanLuisCanalextendsabout100milestoCheck21,nearKettlemanCity.TheSanLuisCanalreachoftheaqueductservesmostlyagriculturalCVPcustomersandconveysSWPwaterstopointssouth.ThejunctionwiththeCoastalBranchoftheaqueductislocated185milesdownstreamofBanksandabout12milessouthofCheck21.TheCoastalBranchprovidesdrinkingwatersuppliestocentralCaliforniacoastalcommunitiesthroughtheCentralCoastWaterAuthorityandtheSanLuisObispoCountyFloodControlandWaterConservationDistrict.FromthejunctionwiththeCoastalBranch,watercontinuessouthwardintheCaliforniaAqueduct,providingwatertobothagriculturalanddrinkingwatercustomersintheserviceareaofKernCountyWaterAgency.
EdmonstonPumpingPlantisatthenorthernfootoftheTehachapiMountains.ThisfacilityliftsSWPwaterabout2000feetbymulti‐stagepumpsthroughtunnelstoCheck41,locatedonthesouthsideoftheTehachapiMountains.Aboutamiledownstream,theCaliforniaAqueductdividesintotheWestandEastBranches.TheWestBranchflows14milestoPyramidLake,thenanother17milestoCastaicLake,thedrinkingwatersupplyintakeoftheMetropolitanWaterDistrictofSouthernCalifornia(MWDSC)andCastaicLakeWaterAgency.PyramidLakehasacapacityof171,200acre‐feetandCastaicLakehasacapacityof323,700acre‐feet.
FromthebifurcationoftheEastandWestBranches,waterflowsintheEastBranchtohighdesertcommunitiesintheAntelopeValleyservedbytheAntelopeValleyEastKernWaterAgencyandthePalmdaleWaterDistrict.DrinkingwatersuppliesaredeliveredtoMWDSCandSanBernardinoValleyMunicipalWaterDistrictfromtwoDevilCanyonafterbaysdownstreamofSilverwoodLake,wherewateristransportedviatheSantaAnaPipelinetoLakePerris,whichistheterminusoftheEastBranch.MWDSCroutinelytakesasmallamountofwaterfromLakePerris.
AdetaileddescriptionoftheStateWaterProjectisprovidedinAppendixA.
2.1.3 Contra Costa Water District
TheContraCostaWaterDistrict(CCWD)isaCVPcontractorthatdivertswatersuppliesfromlocationsinthewesternandsouthernDelta.Figure3showsthelocationsoftheCCWDwatersupplyintakesintheDelta.CCWDdivertswaterunderitsCVPwaterrightsattheRockSloughIntakenearOakley,theOlderRiverIntakenearDiscoveryBay,andtheMiddleRiverIntakeonVictoriaCanal.DependingontheintakeandwherewaterisneededintheCCWDservicearea,the
DeltaNutrients–DrinkingWaterIssues 8 June20,2017
waterisdivertedtointotheContraCostaCanalandconveyedtotreatmentplantsandreservoirslocatedthroughouteasternandcentralContraCostaCountyortoLosVaquerosReservoir.LosVaquerosReservoirstoredwaterisprimarilyusedforblendingintheContraCostaCanalforimprovedwaterquality.CCWDalsohasitsownMallardSloughIntakeinBayPoint,althoughdiversionsatthisintakeareunreliableduetohighsalinityatthispointofdiversion.
2.1.4 Nutrient Concentrations in the Delta and SWP
NutrientdatapresentedinthisreportweredrawnfromtheDepartmentofWaterResources(DWR)MunicipalWaterQualityInvestigation(MWQI)ProgramandfromtheDivisionofOperationsandMaintenance(O&M)waterqualitymonitoringprogram.ThesedatawereusedtoprovideageneralbackgroundonnutrientconcentrationsmeasuredintheDeltaandSWP.
Figure4presentsthetotalnitrogen(totalN)dataandFigure5presentsthetotalphosphorus(totalP)dataforthetributariestotheSacramento‐SanJoaquinDelta(Delta),CliftonCourt,andBanksfortheperiod2004–2010.TotalNandtotalPconcentrationsarelowattheAmericanRiverandtheSacramentoRiveratWestSacramento(WestSacramento)sites.ThereisanobservableincreaseinbothnutrientsattheSacramentoRiveratHood(Hood);however,theHoodconcentrationsofbothnitrogenandphosphorusaremuchlowerthanthosefoundintheSanJoaquinRiveratVernalis(Vernalis).AppendixAincludesfigureswhichshowtheseasonalandspatialvariabilityinnutrientconcentrationsatHood,Vernalis,BarkerSlough,andBanks.
NutrientconcentrationsincreaseconsiderablyintheSacramentoRiverbetweenWestSacramentoandHood,despitetheinflowofthehighqualityAmericanRiver,duetothedischargefromtheSacramentoRegionalWastewaterTreatmentPlantaswellasinputsfromagricultural,industrial,andurbanrunoffsources.ThemedianconcentrationsoftotalN(0.67mg/L)andtotalP(0.08mg/L)atHoodarestatisticallysignificantlyhigherthanthemedianconcentrationsoftotalN(0.29mg/L)andtotalP(0.05mg/L)atWestSacramento.TotalNandtotalPconcentrationsintheSanJoaquinRiverareconsiderablyhigherandmorevariablethanconcentrationsintheSacramentoRiver.ThemediantotalNconcentrationatVernalisof2mg/ListhehighestintheSWPsystem.ThemediantotalPof0.16mg/LcalculatedforVernalisistwicethelevelfoundatHood.
NutrientconcentrationsintheNBAarehigherthanintheSacramentoRiver.ThemediantotalNconcentrationis0.8mg/LandthemediantotalPconcentrationis0.18mg/L.TheSacramentoRiveristheprimarysourceofwatertoBarkerSlough,soitisevidentthatthelocalwatershedsuppliessomenitrogenandasubstantialamountofphosphorustotheNBA.Thereisextensivecattlegrazingandfarmingthroughoutthewatershed,andthereisagolfcourseintheupperpartofthewatershed;allpotentialsourcesofnutrients.
DeltaNutrients–DrinkingWaterIssues 9 June20,2017
Figure 3. Contra Costa Water District Delta Water Intakes
DeltaNutrients–DrinkingWaterIssues 10 June20,2017
AlthoughtheSacramentoRiveristheprimarysourceofwaterdivertedthroughBanksintotheSWPsystem,theSanJoaquinRiverisalsoamajorsourceofwatertoBanks;theSanJoaquinRiver’spercentcontributionvarieswithhydrologyandwaterprojectoperations.ThetotalNconcentrationatBanks(medianof0.88mg/L)isabout30percenthigherthanthemedianconcentrationof0.67mg/LatHood(Mann‐Whitney,p=0.0002)andthedataaremorevariable.ThemediantotalPconcentrationof0.10mg/LatBanksisslightlyhigherthanthe0.08mg/lmedianconcentrationcalculatedatHood(Mann‐Whitney,p=0.0046),withbothdatasetsshowingthesamevariability.Asdiscussedpreviously,themediantotalNconcentrationatVernalisismorethantriplethemedianconcentrationatHood,whereasthemediantotalPconcentrationisaboutdouble.ThismaypartiallyexplainwhythetotalNconcentrationsatBanksincreasemorethanthetotalPconcentrations;however,therearealsoin‐Deltasourcesofnutrientsincludingagriculturaldischarges,wastewatertreatmentplants,andurbanrunoff.Anothercomplicatingfactoristhatnutrientsarenotconservativeconstituents.
DatahavebeencollectedatanumberoflocationsalongtheCaliforniaAqueductfrom2004to2010(SeeAppendixA).NutrientconcentrationschangeverylittleaswaterflowsfromtheDeltathroughtheSBAandtheCaliforniaAqueduct.AslightincreaseintotalNisobservedmovingdownstreamintheAqueductfromCheck21toCheck41duetonon‐projectinflowsfromfourmajorsources(SemitropicWaterStorageDistrict,KernWaterBankAuthority,CrossValleyCanalinflows,andArvinEdisonCanalinflows(ArchibaldConsultingetal.,2012)).MediantotalNconcentrationsareabout1.0mg/LandmediantotalPconcentrationsareabout0.1mg/Lthroughoutthesystem,withtheexceptionoftheCastaicOutletandPerrisOutlet.ThemedianconcentrationsoftotalNandtotalParesubstantiallylowerattheCastaicOutlet.Algaluptakeandsubsequentsettlingofparticulatemattermayberesponsibleforthelowernutrientconcentrationsintheterminalreservoirs.
DeltaNutrients–DrinkingWaterIssues 11 June20,2017
Figure 4. Total N Concentrations in the SWP Watershed: 2004 – 2010
Figure 5. Total P Concentrations in the SWP Watershed: 2004 – 2010
West Sacramento
American
Hood
Mokelumne
Calaveras
Vernalis
Clifton C
ourt
Banks
To
tal
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mg
/L)
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DeltaNutrients–DrinkingWaterIssues 12 June20,2017
CCWDimplementsawaterqualitymonitoringprogramthatincludesmonitoringfornutrientsatCCWDintakefacilitiesandreservoirs.AttheOldRiverIntaketheaverageTotalKjeldahlnitrogenconcentrationwas0.1mg/L(rangeofnon‐detect(ND)to0.8mg/L),andtheaveragetotalphosphorousconcentrationwas0.07mg/L(rangeofNDto0.18mg/L)(seeFigure6).AttheMiddleRiverIntaketheaverageTotalKjeldahlnitrogenconcentrationwas0.2mg/L(rangeofNDto2.2mg/L),andtheaveragetotalphosphorousconcentrationwas0.1mg/L(rangeofNDto1.0mg/L)(seeFigure7).
Figure 6. Total Kjeldahl Nitrogen and Total Phosphorus at Old River Intake: 2010 – 2014
Figure 7. Total Kjeldahl Nitrogen and Total Phosphorus at Middle River Intake: 2010 – 2014
DeltaNutrients–DrinkingWaterIssues 13 June20,2017
2.2 PROBLEMS ASSOCIATED WITH HIGH NUTRIENT LEVELS AND OTHER ENVIRONMENTAL FACTORS
DrinkingwateragenciesthattakewaterfromtheDeltaviatheSWPandCVPfacechallengesduetocyanobacteriaharmfulalgalblooms(cyanoHABs)andmacrophytegrowththatoccurinSWPandCVPconveyancesandstoragefacilities(seeFigure2),asdiscussedfurtherinSection3.0.Whiletherearemanyfactorswhichcanstimulatealgaeandmacrophytegrowth,nutrients,temperature,light,residencetime(particularlyinreservoirs),andwaterclarityareconsideredmajordrivers.
Traditionally,ithasbeenassumedthathighnutrientconcentrationswereresponsibleforcausingperiodiclowdissolvedoxygenlevelsintheStocktonDeepWaterShipChannelandseveraldeadendsloughsonthesouthernandeasternsideoftheDeltaduetothestimulationofalgalgrowth,followedbysenescenceandbreakdownbybacteria(LeeandJones‐Lee2006).Incontrast,itwasalsoassumedthathighnutrientlevelsdidnotencourageprimaryproductivityinsomeregionsoftheDeltawithhighturbidityandlowlight(AlpineandCloern1992,TetraTech2006).However,recenthypothesesdescribedintheDraftNutrientStrategyfortheDelta(CVRWQCB2013)postulatethathighnutrientlevelsmayshiftalgalspeciescomposition,decreasedissolvedoxygenconcentrations,causetasteandodorissues,andincreaseproductivityofblue‐greenalgae(i.e.,cyanobacteria)andnon‐nativemacrophytes(i.e.,waterhyacinth(Eichhorniacrassipes)andBrazilianwaterweed(Egeriadensa)).Therecommendationsformonitoring,research,andmodelingprovidedinSection6.0ofthisdocumentareadvancedtosupportthetestingofthesevarioushypothesestodetermineifnutrientsareofissueintheDeltaanddownstreamconveyanceandstoragefacilitiesastheyrelatetoalgalandmacrophytegrowthandcommunitycomposition.
Elevatedconcentrationsofnitrate(>10mg/L)canalsobetoxictohumansandareassociatedwithmethemoglobinemia,alsoknownas“blue‐baby”syndrome,whichoccursasnitratesinthebodyareconvertedtonitrite,whichreactwithhemoglobininredbloodcellstoformmethemoglobin,whichaffectstheabilityofbloodtocarryoxygenaroundthebody(Knobelochetal.2000).However,ambientnitratelevelsintheDeltahavenotbeenobservedtoapproachtheprimaryMCLof10mg/l.Therefore,themajorDrinkingWaterissuesfacingtheDeltawherenutrientsmaybeafactorcontributingtoaproblemrelatetotherecentchangesincyanobacteriaandmacrophyteprevalenceandcommunitycomposition.ThefollowingsectionbrieflydiscussesthedrinkingwaterchallengesasaresultofcyanobacteriaandmacrophytegrowthintheDeltaanddownstreamsystems,includingtasteandodorissues,cyanotoxinproduction,increaseddissolvedorganiccarbon,diurnalpHswings,andfilterandpumpclogging.
2.3 ALGAE AND MACROPHYTE PROBLEMS IN DRINKING WATER SUPPLIES
2.3.1 Nuisance Algae and Harmful Cyanobacteria Blooms
ACyanobacteriaWorkgroup,convenedbytheDeltaNutrientScienceandResearchProgram,reviewedliteratureforthepurposeofdeterminingwhichpresentandfuturefactorsaremostlikelyassociatedwithcyanobacteriaharmfulalgalbloom(cyanoHABs)prevalenceintheDeltaandconcluded,basedonculturestudies,thatthereisnosignificantorconsistentchangeingrowthratesofcyanobacteriawithchangeinnitrogensourceornitrogentophosphorusratioswhennutrient
DeltaNutrients–DrinkingWaterIssues 14 June20,2017
concentrationsarenotlimiting(Tilmanetal.1982,Tettetal.1985,Reynolds1999,SakerandNeilan2001,Roelkeetal.2003,SundaandHardison2007).BasedoninvestigationscarriedoutintheDelta,nutrientratioshavenotbeenobservedtovaryfrompre‐bloomtobloom,indicatingthatnutrientsarenotlimitingthroughouttheentiretyofthesummerseason(Lehmanetal.2008,Mionietal.2012).TheCyanobacteriaWorkgroupsuggestedthatwhilecyanoHABsobservedintheDeltalikelywerenotduetochangesinnutrientconcentrationsortheirratios,thedurationandmagnitudeofcyanoHABsareinfluencedbytheavailablenutrientsupplyandtherefore,areductioninnutrientscouldreducethedurationandintensityofsuchblooms(BergandSutula2015).Furthermore,althoughnutrientswerenotfoundtolimitgrowthrates,theformofnitrogen(i.e.,ammonia,ammonium,nitrate,nitrite)andnitrogentophosphorusratioshavebeenpostulatedtohaveaneffectonfoodwebdynamicsandcomposition(Dugdaleetal.2007,Glibertetal.2011).
Taste and Odors
Certaincyanobacteriaandactinomycetebacteriaproducechemicalcompoundsthatarenotremovedinconventionalwatertreatmentprocessesandarecapableofcausingunpleasanttastesandodors(T&O)indrinkingwater.T&OincidentsoccurthroughouttheSWPinthetreatedwaterandarecommonlyassociatedwithgeosminand2‐methylisoborneol(MIB)thatareproducedbybenthicandplanktoniccyanobacteria.GeosminandMIBarenon‐toxicorganiccompoundsthatimpartanearthy,muddy,musty‐typeodor/tasteinwaterthatmanyfindunacceptable.Theabilityofindividualstodetectthesechemicalsvaries,butthegeneralpopulationcandetecteithercompoundataconcentrationofabout10ng/L(nanogramsperliter,orpartspertrillion),andsensitiveindividualscandetectevenlowerconcentrations.Asaresult,somewateragencieshaveinstalledadvancedtreatmentprocesses,suchasozonationandpowderedactivatedcarbon,toreducethelevelsoftheseT&Ocompoundsintreateddrinkingwater.
Strainspecificitymakesitdifficulttodetermineapriorithatoccurrenceofaparticulartaxonintheplankton(orbenthos)ofadrinkingwatersourcewillleadtoT&Oevents.Typically,thestrainsresponsibleforT&Oissuesarenotthemostdominantmembersofthecommunityandtherefore,oftengomisdiagnosed(SeeSectionA.3inAppendixA).Forexample,inCastaicLake,aterminalreservoiroftheSWPinsouthernCalifornia,aT&Oeventin1993wasblamedonastrainofPseudanabaenaintheplankton(IzaguirreandTaylor1998).However,PseudanabaenaiscommoninsouthernCaliforniawaters,andmoststrainsisolatedovera23‐yearperiodhavenotcausedT&Oproblems.AccordingtoIzaguirreandTaylor(1998),becauseMIBproductionisararephenomenoninthisgenus,itisdifficulttopredictT&Oeventsinvolvingtheorganism,orthoseinvolvingothertaxasuchasSynechococcus(Izaquirreetal.1984),Hyella,andOscillatorialimosa(IzaguirreandTaylor1995).Thereisalargeliteraturedescribingeffortstoisolateandidentifystrainsofalgae,cyanobacteria,andotherT&Ocompoundproducingorganisms.
BenthiccyanobacteriaareresponsibleformostoftheT&OeventsreportedintheliteratureinterminalreservoirsreceivingwaterfromtheSWP.AlmostalloftheT&OeventsinDiamondValleyLakeareassociatedwithfilmsofbenthiccyanobacteria(OscillatoriaorPhormidiumspp.),whichgrowonthesidesofthereservoirandonthedam.ThebenthiccoloniesinDiamondLakeformonsediments3‐17mdeep(IzaguirreandTaylor2007),usuallyinlatesummer.Thisindicatesthattheyarefrequentlypositionednearthethermocline,wheretheywouldhavegreateraccessto
DeltaNutrients–DrinkingWaterIssues 15 June20,2017
diffusivefluxesofnutrientsreleasedatthesediment/waterinterfaceduringsummerstratification.MIBproducingstrainsofOscillatoriathathavebeenisolatedfromothersouthernCaliforniareservoirs(LakeMathews,LasVirgenesReservoir,LakeBard,LakeSkinner,andSilverwoodLake)arealsobenthicforms(IzaguirreandTaylor2007).Therangeofdepthsandthus,totalsurfaceareaavailabletothesecolonieswillvarypositivelywithwaterclarity.
SampleshavebeencollectedfromuntreatedwaterinSWPfacilitiesbytheDepartmentofWaterResources(DWR)andanalyzedfortheT&Oproducingcompounds,MIBandgeosmin,since2000whenthetechnologytoreadilyanalyzeforthesecompoundsbecameavailable.Figure8throughFigure14showconcentrationsofMIBandgeosminatvariouslocationsalongtheCaliforniaAqueduct,BanksPumpingPlant,andlakeoutletswithpeakconcentrationstypicallyoccurringinthesummermonths.BenthiccyanobacteriaaretheprimarysourcesofT&OcompoundsintheDeltaandinCliftonCourtForebay(DWR2013).ThehighlevelsofMIBandgeosminaretransportedtotheSouthBayAqueduct(SBA)anddowntheCaliforniaAqueduct.MIBandgeosminarealsogeneratedbybenthiccyanobacteriaintheCaliforniaAqueduct,theCoastalBranchandtheEastBranchoftheCaliforniaAqueduct(DWR2013).MIBandgeosminarebothfrequentlypresentathighconcentrationsintheEastBranchoftheaqueduct.Themaximumconcentrationsrecordedwere240ng/LofMIBinMay2003and396ng/LofgeosmininJuly2012(ArchibaldConsultingetal.,2012).PlanktoniccyanobacteriaareresponsibleforT&OproblemsinSilverwoodLake,LakePerris,PyramidLake,andCastaicLakeinSouthernCalifornia(DWR2013)whereconcentrationsreachedashighas1µg/Linsomelocations(SeeFigure11throughFigure14).DWRusesavarietyofaquaticpesticidesintheSWPaqueductsandreservoirstocontrolthesecyanobacteria,asdoestheMetropolitanWaterDistrictofSouthernCaliforniainitsreservoirsthatstoreSWPsupplies.
DeltaNutrients–DrinkingWaterIssues 16 June20,2017
Figure 8. MIB and Geosmin Concentrations at Banks Pumping Plant
Figure 9. MIB and Geosmin Concentrations at Check 41 on the California Aqueduct
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an
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DeltaNutrients–DrinkingWaterIssues 17 June20,2017
Figure 10. MIB and Geosmin Concentrations at Check 66 on the California Aqueduct
Figure 11. Geosmin Concentrations at Castaic Lake Outlet
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DeltaNutrients–DrinkingWaterIssues 18 June20,2017
Figure 12. MIB Concentrations at Castaic Lake Outlet
Figure 13. MIB and Geosmin Concentrations at Lake Silverwood Outlet
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DeltaNutrients–DrinkingWaterIssues 19 June20,2017
Figure 14. MIB and Geosmin Concentrations at Lake Perris Outlet
AreasoftheSWPandtheorganismstargetedbytheDWRAquaticWeedandAlgalBloomControlProgramsareshowninTable1.
Table 1. State Water Project Facilities and Target Organisms Addressed by the California Department of Water Resources Aquatic Weed and Algal Bloom Control Programs (DWR 2013).
State Water Project Facilities Macrophytes Algae
South Bay Aqueduct Unspecific T&O-producing cyanobacteria, Melosira varians, Cladophora sp.
Clifton Court Forebay
Egeria densa Potamogeton pectinalus Myriophyllum spicatum Ceratophyllum demersum Potamogeton nodosus Potamogeton crispus
T&O-producing cyanobacteria
Patterson Reservoir Unspecific Microcystis spp. Cladophora sp.
Dyer Reservoir Unspecific T&O-producing cyanobacteria, Aphanizomenon flos-aquae Anabaena sp.
1
10
100
1000
MIB
an
d G
eo
sm
in (
ng
/L)
MIB
Geosmin
DeltaNutrients–DrinkingWaterIssues 20 June20,2017
State Water Project Facilities Macrophytes Algae
O’Neill Forebay Potamogeton sp. Potamogeton pectinalus L. Stuckenia striata
Unspecific
Coastal Branch Aqueduct Zannichellia palustris L. Potamogeton pectinalus
T&O-producing cyanobacteria, Cladophora sp.
East Branch Aqueduct Unspecific
T&O-producing attached cyanobacteria: Phormidium sp. Oscillatoria sp.
Pyramid Lake Ceratophyllum demersum Myriophyllum spicatum Stuckenia striata
T&O-producing cyanobacteria, Microcystis sp., Gloeotrichia sp., Anabaena sp.
Castaic Lake Unspecific T&O-producing attached and planktonic cyanobacteria, diatoms
Silverwood Lake Unspecific Anabaena lemmermannii
Lake Perris Unspecific
T&O-producing cyanobacteria, Synechococcus sp. Pseudanabaena sp. Anabaena sp.
Quail Lake Unspecific T&O-producing cyanobacteria, Microcystis sp., Gloeotrichia sp., Anabaena sp.
CCWDalsomonitorsfortasteandodorcompoundsintheirfacilitiesincludingtheContraCostaCanalandreservoirs.Monitoringduring2010–2014intheContraCostaCanalnearthecommunityofClyde,whichisalocationinthecanalafterallwatersourceshaveblended,foundgeosminlevelsthatrangedfromNDto80ng/L,withanaverageof5ng/L.MIBconcentrationsrangedfromNDto81ng/L,withanaverageof8.4ng/L(seeFigure15).CCWD’sMallardReservoiralsoexperiencesperiodicalgalbloomsandelevatedlevelsofgeosminandMIB.MonitoringinMallardReservoirduring2010–2014foundconcentrationsofgeosminrangingfromNDto2,200ng/L,withanaverageof43ng/L(seeFigure16).MIBconcentrationsatMallardReservoirrangedfromNDto29ng/L,withanaverageof2.5ng/L(seeFigure17).
DeltaNutrients–DrinkingWaterIssues 21 June20,2017
Figure 15. Geosmin and MIB in Contra Costa Canal at Clyde: 2010 – 2014
Figure 16. Geosmin in Mallard Reservoir: 2010 – 2014
DeltaNutrients–DrinkingWaterIssues 22 June20,2017
Figure 17. MIB in Mallard Reservoir: 2010 – 2014
Filter clogging
Algaeandmacrophytescancauseclogging,pumpingfailure,andtreatmentissuesduringwatertreatmentduetohighconcentrationsoftotalsuspendedsolids(TSS)andanoverabundanceofplanttissue.FiltercloggingalgaeoccurthroughouttheSWP,buttheyareparticularlytroublesomeintheSBA.Thehighconcentrationsofnutrients,combinedwithshallowcanaldepth,abundantsunlight,andwarmwatertemperaturesduringthespring,summer,andfallmonthsleadstoexcessivealgalgrowthintheSBA.ThiscreatesanumberoftreatmentchallengesfortheSBAContractorsandothers.Abenthicdiatom,Melosiravarians,andabenthicfilamentousgreenalga,Cladophorasp.,aretheprimaryalgaethatleadtofiltercloggingandreducedfilterruntimesatSBAwatertreatmentplants.DWRhassetalgalabundancethresholds(algalfluorescence>200unitsandalgalbiomass>5,000mg/m3)fortheSBAthatwhenexceededleadtotheapplicationofalgaecides(DWR2013).
TheprimarymechanismforcontrollingalgalgrowthintheSBAisbyapplicationofcoppersulfate,asthistreatmenthasproventobeaneffectivealgalcontrolmeasure.CoppersulfateisappliedeverytwotofourweeksfromMarchuntilOctoberorNovember,dependinguponwatertemperaturesandalgalconditions.Othercontrolmeasures,suchaslightlimitation,areintheirearlystagesofdevelopmentandtherefore,havenotbeenemployedasaroutinemethodtolimitalgalgrowth.AsshowninFigure18,algalbiomasshasexceeded5,000mg/m3almosteverysummersincedatacollectionbeganin2011,evenwithfrequentapplicationofcoppersulfate.
DeltaNutrients–DrinkingWaterIssues 23 June20,2017
Figure 18. Algal Biomass in the South Bay Aqueduct at Del Valle Check 7
Cyanobacteria (Microcystis) and associated toxin-producing algae
MicrocystisaeruginosawasfirstdetectedintheDeltaintheeasternStocktonDeepWaterShipChannelinSeptember1999.IthasbloomedeveryyearduringthelatesummerandearlyfallthroughoutthecentralandsouthernDeltasinceitsinitialdetection.Microcystisspp.hasbeenfoundinCliftonCourtForebay;BanksPumpingPlant;DyerReservoir,PattersonReservoir,andDelValleCheck7ontheSBA;andtheGianelliintakeinSanLuisReservoirduringthelastthreeyears.Microcystisproducesmicrocystin,apotenthepatoxin(livertoxin).Otheralgalspecies,suchasAnabaena,Aphanizomenon,andPlanktothrixthatproducealgaltoxins(USEPA2012and2015a)havealsobeenfoundatanumberoflocationsintheSWP.SimilartothecyanobacteriawhichproduceT&Ocompounds,toxinproducingcyanobacteriaarenotalwaysthemostdominantmemberofthenaturalcommunityandcansometimesrepresentaverysmallproportionofthebiomass,butstillproduceasignificantconcentrationoftoxins(e.g.,seeAppendixA).
Therearecurrentlynostateorfederaldrinkingwaterstandardsformicrocystins;however,theWorldHealthOrganizationreleasedaprovisionalguidelineof1.0µg/Lformicrocystin‐LRindrinkingwaterin1998.TheUnitedStatesEnvironmentalProtectionAgency(USEPA)addedcyanobacteriaandcyanotoxinstotheCandidateContaminantList2(CCL)in1998,2005,and2009.CyanotoxinsarealsoonthedraftCCL4(2015).USEPApublished10‐daydrinkingwaterhealth
2TheContaminantCandidateListisalistofdrinkingwatercontaminantsthatareknownoranticipatedtooccurinpublicwatersystemsandarenotcurrentlysubjecttoEPAdrinkingwaterregulations.
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
Biomass,mg/m
3
DeltaNutrients–DrinkingWaterIssues 24 June20,2017
advisoriesformicrocystinsandcylindrospermopsininJune2015(USEPA2015b).Healthadvisoriesdescribenon‐regulatoryconcentrationsofdrinkingwatercontaminantsatorbelowwhichadversehealtheffectsarenotanticipatedtooccuroverspecificexposuredurations(e.g.,10‐days).Table2presentstheUSEPAhealthadvisories.
Table 2. US EPA Algal Toxin 10-Day Drinking Water Heath Advisories (applicable to tap water)
Age Group Microcystins (µg/L) Cylindrospermopsin (µg/L)
Children, Six Years and Younger 0.3 0.7
Older Children and Adults 1.6 3.0
DWRinitiatedmicrocystinmonitoringinSWPfacilitiespriortotreatmentin2006.Between2006and2012,dissolvedmicrocystinwasdetectedinafewsamplesatlevelsrangingfrom<1.0to1.7µg/L.In2013,DWRchangedlaboratoriesandmeasurementmethodology.Thenewmethodmeasurestotalmicrocystins(dissolvedandparticulate),includingthemicrocystincontainedinalgalcells.Thisresultedinmorefrequentandhigherconcentrationdetectedatmorelocations.MicrocystinhasbeendetectedinBarkerSloughattheNorthBayAqueductintake,CliftonCourtForebay,BanksPumpingPlant,DyerReservoirontheSBA,theGianelliandPachecointakesinSanLuisReservoir,theO’NeillForebayOutlet(Check13)ontheCaliforniaAqueduct;andinPyramidLake,CastaicLake,andSilverwoodLakeinSouthernCalifornia(seeFigure19throughFigure30).
Table3presentsMicrocystisbiomassandmicrocystindataforCliftonCourtForebay,theforebayfortheBanksPumpingPlantintheSouthDelta,duringtheperiodJuly2013toAugust2015.ThistablepresentsdataforthedatesthateitherMicrocystisbiomassormicrocystinwasdetected.Notably,botharenotalwaysdetectedonthesamedate.TheUSEPA10‐dayDrinkingWaterHealthAdvisoryformicrocystinforyoungchildrenwasexceededninetimesinambientsamplesandtheadultlevelwasexceededtwiceintheCliftonCourtForebayambientsamples(seeTable3).
WithreferencetoFigure19throughFigure29,thehighestmicrocystinconcentrationswerefoundintheSWPreservoirs.ConcentrationsinsamplescollectedatseverallocationsanddepthsinPyramidLakerangedfrom0.23to81.5µg/Linthesummerof2015.SilverwoodLakehadconcentrationsrangingfrom0.30to40µg/Linthesummerof2013.SanLuisReservoirhadconcentrationsrangingfrom0.30to9.8µg/LattheGianelliintake,and0.80to6.5µg/LatthePachecointakein2013.ManyoftheseambientsamplesexceededtheUSEPAHealthAdvisories(applicabletotapwater)forbothchildrenandadults.
DWRstartedsamplingforcylindrospermopsinin2012.Samplesarecollectedonlywhenalgaeknowntoproducethistoxinarepresent.CylindrospermopsinhasonlybeendetectedinLakePerrisinSouthernCaliforniawheretheconcentrationsrangedfrom0.10to0.19µg/Lin2015(seeFigure30).TheseconcentrationsarebelowtheUSEPAHealthAdvisoriesforthetoxinpresentedinTable2.
DeltaNutrients–DrinkingWaterIssues 25 June20,2017
Table 3. Microcystis Biomass and Microcystin Concentrations in Clifton Court Forebay.
Date Microcystis
Biomass, mg/m3 Percent of Total
Biomass Microcystin,
µg/L(1)
07/22/13 7.9 42.5
08/05/13 0.8 4.9
09/16/13 0.30
11/12/13 86.5 91.9
11/18/13 115.0 98.7
06/23/14 0.19
07/07/14 112.50 28.45 2.98
07/22/14 1.11
08/04/14 0.46
08/18/14 200.9 85.4 0.64
09/02/14 23.0 9.4 2.17
09/15/14 1.30
09/22/14 257.5 49.4
09/29/14 0.41
10/13/14 0.22
11/17/14 8.1 10.0
07/06/15 0.37
08/10/15 0.17 1 Bolded values exceed US EPA Algal Toxin 10-Day Drinking Water Heath Advisories of 0.3 µg/L for children 6 years and younger.
DeltaNutrients–DrinkingWaterIssues 26 June20,2017
Figure 19. Total Microcystin in Barker Slough
Figure 20. Total Microcystin in Clifton Court Forebay
Figure 21. Total Microcystin in Banks Pumping Plant Figure 22. Total Microcystin in Dyer Reservoir
0.0
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Health Advisory Adults
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DeltaNutrients–DrinkingWaterIssues 27 June20,2017
Figure 23. Total Microcystin in Lake Del Valle Check Figure 24. Total Microcystin in San Luis Reservoir at Pacheco intake
Figure 25. Total Microcystin in San Luis Reservoir at Gianelli Intake Figure 26. Total Microcystin in O’Neill Forebay Outlet
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DeltaNutrients–DrinkingWaterIssues 28 June20,2017
Figure 27. Total Microcystin in Pyramid Lake
Figure 28. Total Microcystin in Castaic Lake
Figure 29. Total Microcystin in Lake Silverwood Figure 30. Total Cylindrospermopsin in Perris Lake
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DeltaNutrients–DrinkingWaterIssues 29 June20,2017
Dissolved Organic Carbon Production
AmbientnutrientlevelsintheDeltacancauseanincreaseintotalanddissolvedorganiccarbonconcentrationsasaresultofincreasedprimaryproductivity.Increasedproductivitycausesthereleaseoforganiccompoundsintothedissolvedorganiccarbonpool,asdoesthedeathanddecompositionofaquaticplantsandalgae.Dissolvedorganiccarbonisadrinkingwaterconcernprimarilyduetotheformationofcarcinogenicbyproductsthatareformedduringdisinfectionatawatertreatmentfacility(TetraTech2006).Chlorine,whichisaddedtodisinfectdrinkingwater,reactswithdissolvedorganiccarbontoformcompoundssuchastrihalomethanesandhaloaceticacids(generallyreferredtoadisinfectionbyproductsorDBPs)whicharebothknowncarcinogens(Flecketal.,2004).Theamountoforganiccarbonthatmustberemovedbyawatertreatmentplantisbasedontheconcentrationsoftotalorganiccarbon(TOC)andalkalinityinthesourcewater,asprescribedintheUSEPAComprehensiveDisinfectantsandDisinfectionByproductRules(Stage1andStage2(D/DBPRule))–seeTable4.AlgalproductionintheSWPfacilitiesresultsinhigherconcentrationsoftotalorganiccarboninthesystem.Currently,coppersulfateadditionistheonlycontrolmeasureusedtomanagealgalgrowth.TherelativecontributionfromtheDeltaandfromprimaryproductionintheSWPsystemisnotknown.
Table 4. US EPA D/DBP Rule Requirements for TOC Removal.
Subpart H systems1 that use conventional filtration treatment are required to remove specific percentages of organic materials, measured as total organic carbon (TOC) that may react with disinfectants to form DBPs. Removal must be achieved through a treatment technique (enhanced coagulation or enhanced softening) unless a system meets alternative criteria. Systems practicing softening must meet TOC removal requirements for source water alkalinity greater than 120 mg/L as CaCO3.
Source Water TOC (mg/L)
Source Water Alkalinity, mg/L as CaCO3
0-60 >60 to 120 >120
> 2.0 to 4.0 35.0% 25.0% 15.0%
> 4.0 to 8.0 45.0% 35.0% 25.0%
> 8.0 50.0% 40.0% 30.0%
1. Subpart H systems are public water systems using surface water or ground water under direct influence of surface water as a source that are subject to the requirements of Subpart H of 40 CFR Part 141 (40 CFR 141.3).
For additional information see: https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100C8XW.txt
ThedirectcontrolofTOCandDOClevelsintheDeltawasconsideredindetailaspartofanextensivestakeholdercollaborativeknownastheCentralValleyDrinkingWaterPolicyworkgroupintheperiodfrom2002through2012.ThateffortculminatedinfindingsthatambientTOCandDOClevelswerenotexpectedtoincreaseatdrinkingwaterintakesinthenearfutureandthatadditionalwatertreatmentwouldnotberequiredtoaddressexistingTOCandDOClevelsunderthecurrentSafeDrinkingWaterActregulatoryrequirements(CentralValleyDrinkingWaterPolicyWorkgroup2012).
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Diurnal Swings in pH
WideswingsinpHperiodicallyoccurintheSBA,asshownFigure31.ExcursionsofpHabovetheupperlimitoftheUSEPASecondaryMaximumContaminantLevel(MCL)of8.5standardunits(s.u.)fortheparameterwereobservedduringMay,June,September,November,andDecember2016.IncreasesinpHintheSBAaremostlikelyaresultofphotosyntheticremovalofcarbondioxide(CO2)fromthewatercolumnalongthelengthoftheopencanal,primarilybyalgae.ThesepHexcursionsareproblematicfortheSBAContractorsbecausethepHofthetreatmentplantinfluentmustbeadjustedtobewithinapHrangeof6.5–8.5standardunits(s.u.)forthedrinkingwatertreatmentprocesstomeetUSEPAsecondarystandards3forpHandtheSacramento‐SanJoaquinBasinPlan4objectivesandtoeffectivelydisinfectthewater.In2016,pHdatacollectedintheSBAexceededapHof8.5ontwo(2)separateoccasions.TrackingrapidpHchangesandadjustingacidfeedmakesitdifficulttomeetwatertreatmentregulationsandincreasestreatmentcosts.TreatmentcostsincreasebecauseacidisaddedtolowerthepHoftherawwatergoingintotheplantandthenmustbesubsequentlyoffsetbytheadditionofabasetoraisethepHofthefinishedwaterleavingtheplanttomeettherequirementsoftheLeadandCopperRule.
Solids Production
Wateragenciesmustuseadditionalquantitiesofchemicals,suchasferricchloride,alum,andpolymersinthewatertreatmentprocesstoremovealgaefromthesourcewater.Thisproducesgreaterquantitiesofsolidsinadditiontotheoverabundanceofplanttissuethatmustbedisposedoftoavoidcloggingandpumpingfailure,resultinginhighersolidsdisposalcosts.
2.3.2 Macrophytes
TheMacrophyteWorkgroupcametonoconclusionregardingtheeffectofnutrientsintheDeltaontriggeringorincreasingnon‐nativemacrophyteexpansionacrosstheDeltainrecentyears.TheexpansionofinvasivemacrophytesintheDeltaobservedwhencomparingtheresultsoftwomappingeventsin2008and2014cannotbelinkedtoachangeinambientnutrientconcentrations,asanevaluationofnutrientsintheDeltafrom2004–2014foundnoobvioustrendsinammonium,nitrate,phosphate,totalN,ortotalPconcentrationsacrossmultipleDeltamonitoringlocations(LWA2015).Tothisend,theMacrophyteWorkgroupconcludedthattheexpansionofinvasivemacrophytesinrecentyearscannotbelinkedtochangesinwatercolumnnutrientconcentrationsacrosstheDeltaduringthesameperiodandsuggestedthatotherfactorsbesidesnutrientsmightbecontributingtotheextensiveplantgrowth(BoyerandSutula2015).
3https://www.epa.gov/dwstandardsregulations/secondary‐drinking‐water‐standards‐guidance‐nuisance‐chemicals
4http://www.waterboards.ca.gov/centralvalley/water_issues/basin_plans/2016july_1994_sacsjr_bpas.pdf
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Figure 31. pH levels in South Bay Aqueduct during 2016
Obstruction of Conveyance and Pumping Facilities
ExcessivegrowthofmacrophytesandalgaecreatewaterconveyanceproblemsatanumberoflocationsintheSWP.MacrophyteaccumulationcanbesosevereatBanksthatpumpingisrestrictedorhalted.Duringcertainperiods,upto20cubicyardsofmacrophytesareremovedeachdayfromthetrashracksatBanks.MacrophytesalsocreatemajoroperationalproblemsinO’NeillForebay,theCaliforniaAqueduct,andtheCoastalBranch.MacrophytesarealsopresentinthelittoralzoneofthefourSouthernCaliforniaSWPreservoirs.DWRexpendsasignificantamountoftimeandmoneycontrollingmacrophytesintheSWP.Copperproductsareusedinmanylocations,althoughtheyhavenotbeenusedsince2006inCliftonCourtduetopotentialimpactsonthreatenedandendangeredspecies.MechanicalharvestingisusedinCliftonCourtForebayandO’NeillForebayandsomesectionsoftheaqueductarescrapedbydraggingalargechainalongtheaqueductlining.
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3.0 Factors Influencing Nutrient-Related Drinking Water Issues
ThefollowingsectionprovidesinformationpertainingtothefactorsthatmayinfluencethecyanobacteriaandmacrophyteprevalenceproblemswithintheSWPidentifiedinSection2.0.TheinformationpresentedbelowwastakenfromthewhitepapersproducedbytheCyanobacteriaandMacrophyteWorkgroups.
3.1 LIGHT/SOLAR IRRADIANCE
Allphotosyntheticorganismspossessacharacteristicphotosynthesis‐irradiancerelationshipwheretherateofphotosynthesisincreaseswithincreasedirradianceuptosomepointwherethelight‐harvestingcomplexofthephotosystembecomesoverwhelmedandphoto‐inhibition(i.e.,adeclineinphotosyntheticrate)occurs.Cyanobacteriahavecarotenoidpigmentsintheirphotosystemsthatprotectthemagainstphoto‐inhibitionatagivenirradiance,ascomparedtoaphotosyntheticorganismlackingsuchprotectivepigments(Huismanetal.1999,Reynolds2006).
Microcystisgrowthispooratlowandmixedlight,butgrowsveryefficientlyathighirradiances;especially,thosespeciesofMicrocystisthatproducetoxins(Huismanetal.2004,Reynolds2006,Careyetal.2012).Microcystisalsoshowspositivebuoyance,whichallowsittogrownearthewatersurfaceinpoorlymixedconditions.PhytoplanktonthatshowlessbuoyancycanbecomeshadedoutbysurfacegrowthsofMicrocystisunderlowmixedconditions(Careyetal.2012).Otherspeciesofcyanobacteria,includingCylindrospermopsisraciborskiiandPlanktothrixsp.aregoodcompetitorsatlowlightlevelsandgrowwellwithinthewatercolumnunderlowirradiances.C.raciborskiialsogrowswellathighirradiances,makingitwell‐suitedtoproduceharmfulcyanobacterialblooms(cyanoHABs)underavarietyofenvironmentalconditions.
LightconditionsintheDeltaaregenerallyadequateforfloatingmacrophytes,suchasE.crassipes(waterhyacinth).Attenuationofphotosyntheticallyactiveradiation(PAR,wavelengthsof400–700nm)inthewatercolumnbysuspendedparticles,includingphytoplankton,canlimitphotosynthesisofsomesubmersedmacrophytes.StudiesofE.densa(Brazilianwaterweed)growthunderdifferentlightconditionsshowthesubmersedmacrophytetohavevaryingresponsestochangesinirradiance,withonestudyshowingthemacrophytetohavelowerbiomassunderlowlightlevelsascomparedtohigherlevels(BorgnisandBoyer,unpublisheddata),andanotherstudyshowinganincreaseinbiomassatlowlightlevelsduetoanextensionoftheplant’scanopyupwardthroughthewatercolumn(RodriguesandThomaz2010).ThebuoyancyofE.crassipesallowsittoshadeoutanyphotosyntheticorganismgrowingwithinthewatercolumnandthus,potentiallyaffectsitsabilitytocompetewithotherspeciesunderamodifiedlightregime.Withregardtosubmersedmacrophytes,aspeciesthatcaneffectivelyoutgrowitscompetitorunderambientlightconditionsintheDeltahastheabilitytoshadeoutitscompetitorsand/orutilizemoreoftheavailableresourcestothedetrimentofcompetingspecies.
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3.2 WATER CLARITY
TheDeltahashistoricallybeenviewedbyresearchersaslightlimitedduetohighturbidity,andthisconditionhasbeenusedtoexplain,inpart,theoveralllowproductivityoftheestuaryinthepresenceofnutrientconcentrationsthoughtsufficienttocauseeutrophication(ColeandCloern1984,1987).Lightlimitationislikelytobemostsevereinturbidwatersoftheestuarywhichareaffectedbywind‐andtide‐drivenverticalmixingandre‐suspensionofinorganicsediment,andisparticularlyhighinshallowareasandareassubjecttostrongwinds(Kimmereretal.2012).Inlocalizedareaswherelightlimitationisn’tlimitingprimaryproductivity,secondaryfactors,suchasnutrientavailability,temperature,salinity,andphotoperiod,cansupportalgalblooms(ColeandCloern1984).Deltawatershaveshowedincreasedclarityoverthepast50years.WrightandSchoellhamer(2004)foundthatsuspendedsedimentsfromtheSacramentoRivertotheDeltahavedecreasedbyabouthalfduringtheperiod1957to2001,whileJassby(2008)showeda2to6%decreaseperyearinsuspendedparticulatematterbetween1975and2005.
Asdiscussedabove,increasedirradiancecanimpartacompetitiveadvantagetothosespeciesthathaveprotectivepigmentstolimitoravoidphoto‐inhibitionunderconditionsofhighirradiance,thosespecieswithhighphotosyntheticratesunderhighirradiance,andthosespeciesthatexhibitlowphotosyntheticefficiencyatlowlightlevels.Anincreaseinwaterclaritywouldresultinanincreaseinirradianceinthewatercolumn,whichwouldbenefitthosespecies–particularly,cyanobacteria,suchasMicrocystisandC.raciborskii–thatgrowwellunderhighlightconditions.ResearchershaveobservedanincreaseintheabundanceofStuckeniapectinata(sagopondweed),anativesubmersedmacrophyte,intheDeltaoverthelast20yearsandhavepositedincreasedwaterclarityandthusgreaterlightavailabilitymaybepartiallyresponsibleforitsexpansion(WrightandSchoellhamer2004;Schoellhamer2011;Hestiretal.2013).
3.3 TEMPERATURE
Increasesintemperature,uptosomecriticalthreshold,areexpectedtoincreasetheestablishmentandgrowthratesofphytoplanktonandfloatingandsubmersedmacrophytes.Temperatureisconsideredakeyfactorthatcontrolsthegrowthrateofcyanobacteria(RobartsandZohary1987,Butterwicketal.2005,Watkinsonetal.2005,Reynolds2006,PaerlandHuisman2009).Cyanobacteriaisolatedfromtemperatelatitudes(i.e.,excludingpolarregions)exhibitgrowthoptimaattemperaturesbetween25and35°C(Reynolds2006,Lurlingetal.2013).SpeciesresponsibleforcyanoHABsshowgrowthoptimawithinthisrange,withAnabaenaspp.observedtohaveoptimumgrowthat25°C,C.raciborskiiandPlanktothrixagardhiiat27.5°C,andtwoMicrocystisaeruginosastrainsat30‐32.5°C(Lurlingetal.2013).Cyanobacteriatypicallyshowlowergrowthratesatcoldertemperaturesandhighergrowthratesatwarmertemperaturesascomparedtootherphytoplanktontaxa,suchasdiatomsanddinoflagellates(Boydetal.2013,Butterwicketal.2005,Kudoetal.2000,Lurlingetal.2013,YamamotoandNakahara2005).Asevidenceofthis,decreasesintemperaturethatoccurinthefallandwinterareobservedtocoincidewithnon‐activegrowthphasesinphytoplankton.Differencesintemperaturegrowthoptimaamongvariousphytoplanktontaxaarehypothesizedtohaveimportanceininfluencingphytoplanktoncommunitycompositionasglobalclimatechangeproducestemperaturesabove20°Cwithmoreregularity(Lehmanetal.2005,PaerlandHuisman2008).
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T&Oeventshavealsobeenfoundtobecorrelatedwithtemperatureinsomesystems.Regressionapproachesusingasuiteofenvironmentalvariableshaveshownairand/orwatertemperaturetobeastrongcorrelatewithT&Ocompoundconcentrationsinatleastfourreservoirs(Tungetal.2008;Uwinsetal.2007;Yenetal.2007).
Withrespecttomacrophytes,increasedgrowthtendstocauseareductioninflowsurroundingastand,whichcausesincreasesinlocaltemperaturesthatfurtherenhancegrowthuptosomelimitingtemperature.LaboratorygrowthstudiesofE.densashowedincreasesinbiomassatawatertemperatureof22°C,reducedbiomassproductionat26°C,andgreatreductionsinbiomassat30°C(BorgnisandBoyer,inpress).Similartophytoplankton,decreasesintemperaturethatoccurinthefallandwinterareobservedtocoincidewithsenescenceanddiebackinmacrophytes.DiebackofE.crassipeshasbeenobservedintheDeltaduringperiodsoffrostandfreezingtemperatures(Foe,pers.comm.;Khanna,pers.comm.;ascitedinBoyerandSutula2015).
3.4 RESIDENCE TIME/FLOW
Residencetimeisameasureofhowlonganobject(e.g.,fish,plant,pollutant,parcelofwater)remainsinadefinedregion.Itisagoodmeasureofthelengthoftimeanobjectstaysintheestuary.Deltaresidencetimeisaffectedbyinflows,seasonalchangesinhydrology,diversions/exports,tides,physicalstructuresofwaterchannels(i.e.,deadendsloughvs.riverchannel),andtheoperationofstructuressuchasgatesandbarriers.Flowvelocitycertainlyhasalargeimpactonresidencetimesashigherflowsproduceshorterresidencetimesandlowerflowspromotelongerresidencetimes.Along‐termtrendsanalysis(1990–2004)ofDeltaresidencetimeperformedbyDWR’sDeltaModelingSection5foundnosignificantdifferencesinresidencetimeindexesfortheSacramentoandSanJoaquinriversovertheperiodanalyzed.However,thestudydidfindthefollowing:SacramentoRiverresidencetimewashigherduringthedrierwateryearsoftheearly1990s;SanJoaquinRiverresidencetimewashigherinlatefall/earlywinterintheearly1990s;latesummerandearlyfallperiodsshowedthehighestresidencetimes;laterwinterexhibitedthelowestresidencetimes;andspringfeaturedthegreatestvariabilityinresidencetimes.
Longerresidencetimesgenerallypromotegreaterexposuresoforganismstotheirphysicalandbiogeochemicalenvironments.Lowerflowsandlongerresidencetimehelptoestablishmacrophytebedsthatcaneventuallylowerflowsandalterlocalhabitatsthemselves,whichpromotetheirowncontinuedgrowth(BoyerandSutula2015).Lowerflows,altereddepositionofsuspendedsediments,andincreasedtemperaturescanleadtoalteredhabitatsthatpromotethegrowthofsomeorganisms(e.g.,macrophytes,phytoplankton,fish,zooplankton,etc.)overothers.Cyanobacterialabundance,cellsize,andtoxinconcentrationarealsopositivelycorrelatedtoincreasedresidencetime(Elliott2010,Romoetal.2013).
5Posteravailableat:http://baydeltaoffice.water.ca.gov/modeling/deltamodeling/presentations/DeltaResidenceTimeResults_mmierzwa.pdf
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3.5 SALINITY
AmbientsalinityintheDeltaistypicallymanagedtoprovidefreshwaterformunicipal,industrial,andagriculturalbeneficialuses(Moyle et al. 2010).DiminishedfreshwaterflowsintotheDeltaduringtherecentdrought(2011–2015)haveresultedinincreasedsalinities(upto5pptormore)reachingasfareastasShermanIsland(BoyerandSutula2015).SealevelriseandchangesinthetimingandmagnitudeofsnowmeltduetoglobalclimatechangearehypothesizedtoincreaseDeltasalinityby1to3pptby2090(Knowles and Cayan 2002).SalinitymeasurementstakeninthewesternDeltabytheC&HSugarRefiningCompanysincetheearly1900shaverevealedthatsalinityintrusioninSuisunBaynowoccursfourmonthsearliereachyearthanhistorically;MarchascomparedtoJuly(Contra Costa Water District 2010).
Freshwatercyanobacteriacapableofformingtoxinsshowarangeoftolerancesforsalinity.TheleasttolerantisCylindrospermopsis,whichshowsdecreasedgrowthabove2.5ppt.AnabaenopsisandNodulariaspp.canthriveatsalinitiesfrom5‐20ppt(Moisanderetal.2002).Microcystisaeruginosacantoleratesalinitiesupto10pptwithoutachangeingrowthrateascomparedtothatobservedwhenthealgaisgrowninfreshwater(Tonketal.2007).ThewhitepaperproducedbytheCyanobacteriaWorkgroupconcludedthatsalinitymaynotbeastrongbarrierthatrestrictstheoccurrenceofcyanoHABsintheDelta(Berg,andSutula2015).
AstudythatinvestigatedthesalinitytoleranceofE.densafoundthegrowthofthemacrophytetobestronglylimitedbyincreasesinsalinity,withlossofbiomassatasalinityof5pptandmortalityanddecompositionatsalinitiesof10and15ppt(BorgnisandBoyer,inpress).ThenativepondweedS.pectinataisexpectedtohavethegreatestsalinitytoleranceamongallmacrophytesintheDeltabasedongreenhousegrowthexperimentsthatshowedbiomassaccumulationwithincreasedsalinitiesupto15pptascomparedtocontrols(BorgnisandBoyer,inpress).E.crassipeshasbeenshowntoundergostressatsalinitiesaslowas2.5ppt(Haller et al. 1974)andexperiencemortalityatsalinitiesabove6–8ppt(Muramotoetal.1991;OlivaresandColonnello2000).
3.6 NUTRIENT CONCENTRATIONS AND RATIOS
TheSanFranciscoEstuary(SFE),whichincludestheSacramento‐SanJoaquinDelta,SuisunBay,SanPablo,CentralandSouthBays,isanexampleofanaquaticecosystempossessingnitrogenandphosphorusconcentrationssufficienttoproduceeutrophication,yet,overall,itfeatureslowphytoplanktonproduction(Cloern2001;Jassbyetal.2002).ItsannualloadingratesofbothtotalNandtotalParegreaterthanthosemeasuredinChesapeakeBay,buttheSanFranciscoEstuaryhistoricallyexhibitednoneofthephytoplanktonbloomscharacteristicoftheChesapeake(Cloern2001).IntheSFE,itiswellestablishedthatfactorssuchasturbidity(actingtolimitlightpenetrationinthewatercolumn),freshwaterflow,residencetime,andbenthicgrazingbybivalvesalldecreasethesensitivityofthesystemtonutrientloading(Cloern2001).Jassbyetal.(2002)showedthatincreasesordecreasesinnutrientlevelsintheDeltahavelittleeffectontheecosystem’sprimaryproductivityduetothephysicalfactorsthatexertastrongerinfluenceonphytoplanktonproductionthanambientnutrientconcentrations.Inrecentyears,someresearchershavehypothesizedthattheformsofN(ammoniumversusnitrate)availableforuptakeinthesystem(Wilkersonetal.2006)andtheratioofNtoPinthesystem(Glibert2010)areactingto
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controltheprimaryproductivityoftheSFEtoagreaterdegreethanoncethought.ThosehypothesesareaddressedintheNutrientFormsandRatioswhitepaperproducedin2017aspartoftheDeltaNutrientScienceandResearchProgram.
3.7 DISSOLVED INORGANIC CARBON
Theprocessofphotosynthesisallowsplantsandotherorganismstoconvertlightenergyintochemicalenergythroughuptakeandconversionofinorganiccarbondioxideandwatertoorganiccarboncompounds(sugars)andoxygen.Floatingmacrophytescanaccessadequatecarbondioxidefromtheatmosphere,butphytoplanktonandsubmersedmacrophytesmustobtaintheircarbonsourcefromthewatercolumnintheformofdissolvedinorganiccarbon(DIC).AsphotosynthesisbyaquaticplantsandalgaepreferentiallyremovesCO2fromthewatercolumn,carbonicacid(H2CO3)becomesmoreprevalentandpHconcentrationsincrease.Thisleadstobicarbonate(HCO3‐)becomingamoreprominentformofDICinthewatercolumn(Sand‐Jensen1989;Santamaría2002).WhenphotosynthesisremovesCO2fromthewatercolumnataratefasterthanatmosphericCO2andrespirationcontributeCO2tothewatercolumn,ahigherpHconditionisformedwherebicarbonatebecomestheprimaryformofDICavailabletophotosyntheticorganisms.Macrophytesthatcanutilizebicarbonateefficiently,suchasE.densaandCeratophyllumdemersum(coontail;asubmersed,nativeperennial)(Cavallietal.2012),mayhaveacompetitiveadvantageoverthosespeciesthatdonotgrowaswellwithbicarbonateasaDICsource.Inadditiontopotentialcompetitiveadvantageforsomeorganisms,theconversionofDICtodissolvedorganiccarbon(DOC)viaphotosynthesismayresultindrinkingwaterqualityproblemsduetotheformationofcarcinogenicbyproductsfromthedisinfectionprocessasdiscussedearlierinSection2.0.
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4.0 Management of Identified Issues
4.1 MANAGEMENT OPTIONS
ThissectiondiscussespossiblemanagementoptionstoaddressseveraloftheimportantissuesdiscussedintheprevioussectionsregardingimpactstoDrinkingWatersourcedfromtheDelta.
4.1.1 Nutrient Load Management
Taste and Odors
NutrientcontrolmeasureshaveproventobeineffectiveasmanagementtoolstocontrolT&OeventsorthedistributionandabundanceofT&O‐causingmicrobesinthefewsystemswhichhavestudiedtheissue,althoughitisunclearwhethertheresultsfromothersystemsareapplicabletotheDeltaandwatersupplysystemsthattransportandstoreDeltawater.OutbreaksofChrysophytes(taxonomicgroupcontainingdiatoms,yellow‐green,andgolden‐brownalgae),andtheirpolyunsaturatedfattyacid(PUFA)derivatives,showlittleapparentrelationshiptonutrientsonabroadscaleacross91northtemperatelakesinCanada(Watsonetal.1997;Watsonetal.2001a).Furthermore,incertaincasesremedialnutrientreductionmayactuallyincreaseepisodesofChrysophyteblooms(e.g.,Juttneretal.1986;Yanoetal.1988;Nicholls1995).WhereT&Oepisodeshavebeenlinkedtoplanktoniccyanobacteria,theeventsarenotwell‐explainedbythenutrientstatusorplanktonicproductivityofthesystems(e.g.,Watsonetal.2008).
Insomecases,remedialactionplansforT&Oproblemswerefoundtobeunsuccessfulbecausetheyattemptcontrolofnoxiousmetabolitesthrougharelianceonwatertreatmentandbroad‐scalenutrient–biomassmodels.Nutrientcontrolapproachesareunderminedbyseveralfactors,includingthefactthat(1)differentT&O‐compoundproducingtaxashowdisparatepatternsacrossnutrientandmixingregimes,(2)epibenthicandperiphyticmicrobesarewidespreadculpritsintheproductionofT&Ocompounds–andgrowthofattachedmicrobesismoreweaklylinkedtoconditionsinthewatercolumnthanphytoplankton,(3)deep‐layercyanobacteriamaxima,suppliedbyinternallyrecyclednutrientsinthehypolimnionofastratifiedsystem,canbeasourceofT&Ocompounds,(4)nutrientreductionstrategieshaveincreasedwatertransparencyandlittoralproductioninmanysystems,improvingconditionsforattachedalgae,and(5)othergroupsofMIBandgeosmin‐producingorganismsarenotalgae,butactinomycetebacteria,myxobacteria,fungi,andothers.Proactivemanagementoftasteandodorissuesneedstoconsiderthesourcesoftheproblembyidentifyingtheenvironmentalandbiologicalagentsandtheirpotentialcontrols,includingecologicallysoundwatershedandsourcewaterremediationandmanagement(Juttner&Watson2007).
Althoughsurfacebloomsareperceivedasprimarysourcesofwaterodor,twiceasmanyknownodor‐causingcyanobacterialspeciesareepibenthic,notplanktonic(Jutter&Watson2007).Inaddition,twocyanobacteriagenera(HyellaandMicrocoleus),whichformbiofilmsonaquaticmacrophytes,havebeenassociatedwithT&Oevents.AttachedcyanobacteriahavebeenimplicatedassourcesofMIBorgeosmininmanystudiesoflakes,reservoirs,orrivers(Burlingameetal.1986;
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Sugiuraetal.1998;Watson&Ridal2004;Bakeretal.2006).Consequently,decreasesinphytoplanktonicbiomass(suchasmightbetheaimofnutrientreductionstrategies)couldhavetheunintendedconsequenceofincreasingtheavailablesubstrateforthemainculpritsofT&Oepisodesinthesereservoirs.
Cyanobacteria
TheCyanobacteriaWorkgroupconcludedthattheinitiationofMicrocystisbloomsareprobablynotassociatedwithchangesinnutrientconcentrations,theformsofthenutrients(e.g.,ammonium)ortheratiosofNtoPintheDelta(BergandSutula2015).Therefore,itisunlikelythatnutrientcontrolwillhaveaneffectonlimitingbloominitiationsofcyanoHABs,suchasMicrocystis.However,theWorkgroupconcludedthatnutrientreductionmightlimitbloomduration,intensity,andpossiblygeographicextent.Inordertoachievethesechangesnutrientswouldlikelyneedtobemanagedtobringtheirconcentrationsdowntoalevelthatwaslimitingtocyanobacteriagrowth.
Macrophytes
TheMacrophyteWorkgroupdeterminedthat,duetotheinconclusiveconnectionbetweennutrientconcentrationsandmacrophyteprevalenceintheDelta,theeffectthatnutrientmanagementwillhaveoncontrollinginvasivefloatingandsubmersedmacrophytesisuncertain.OthermanagementoptionsidentifiedbytheWorkgroupincludedmechanical,chemical,biologicalcontrol,andintegratedcontrolmethods,aswellasbarrierstoprotectsensitiveareas.Thegrouprecommendedadditionalstudiestodeterminethebestcontrolmechanism(Boyer&Sutula2015).
4.1.2 Harvesting (macrophytes)
TheMacrophyteWorkgroupfoundthatmechanicalremovalispracticedincertainareasoftheDelta,butmaynotalwaysbeeffectiveandcanexacerbatetheproblemiffragmentsofplantsarecreatedwhichserveaspropaguleswhichcanseednewpopulationsindistantlocationsoftheDelta.MechanicalremovalofE.Densahasoccurredbutcauseddistantpopulationstoestablishduetopropaguleformation(Anderson2003;Spenceretal.2006).MechanicalgatheringofE.Crassipeshasbeeneffectiveinlimitedareas;however,theremainingshreddedpiecesoftheplantseitherneedtoberemovedwhichincursasignificantcostor,ifleftinplace,willdecomposethusre‐mineralizingnutrients,loweringdissolvedoxygen,andpotentiallyseedingfuturepopulationsthroughpropagulegeneration(Greenfieldetal.2007).
AUnitedStatesDepartmentofAgricultureAgriculturalResearchService(USDA‐ARS)programinvestigatedintegratedcontrolmethodsforbothE.densaandE.crassipesanddevelopedamappingapplicationtotrackdevelopmentofproblempopulationsinordertoprioritizeharvestingtreatmentlocations.ThetoolisusedtotargetnurserypopulationsintheDeltathatserveassourcesforearlyseasoninfestations(Brendaetal.2015).MechanicalharvestingisalsousedinCliftonCourtForebayandO’NeillForebay,andsomesectionsoftheaqueductarescrapedbydraggingalargechainalongtheaqueductlining.
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4.1.3 Biological Control (macrophytes)
Biologicalcontrolmechanismscanincludeintroducingcompetitorsorgrazerstohelpcontrolthepopulationofinvasivemacrophytes.CertainspecieswereintroducedtotheDeltaintheearly1980sinanattempttocontrolE.crassipes,includingtheweevil,Neochetinabruchi,whichbecameestablished,butdidnotresultinanyeffectivereductionoftheE.crassipespopulation(Stewartetal.1988).TheMacrophyteWorkgroupalsodetailedtheongoingintroductionoftheplanthopper,Megamelusscutellaris,forE.crassipescontrolwhichisbeingmanagedbytheUSDA‐ARSandtheCaliforniaDepartmentofFoodandAgriculture(CDFA)(BoyerandSutula2015).ThisorganismhasbeenshowntobeeffectiveinreducingtheE.crassipespopulationinFlorida.
4.1.4 Chemical Additions (e.g. copper sulfate, etc. for nuisance algal blooms, taste and odor episodes)
TheprimarymechanismforcontrollingalgalgrowthintheDeltaandvariouslocationsintheSWPisbyapplicationofcoppersulfateorothercopperproducts.IntheSBA,coppersulfatehasbeenappliedeverytwotofourweeksfromMarchuntilOctoberorNovembersince2011,dependinguponwatertemperaturesandalgalconditions.Thechemicalapplicationiseffectiveinreducingtotalalgalbiomasstopreventfilterclogging;however,evenwiththeapplicationbiomassreachesconcentrationshighenoughtoaffectfilteringeverysummer(SeeSection2.2.1).Copperproductshavenotbeenusedsince2006inCliftonCourtduetopotentialimpactsonthreatenedandendangeredspecies.
Therearepotentialunintendednegativeconsequenceswithusingcoppersulfateandotherchemicaladditivestotreatalgalblooms.OnestudyinaMinnesotaLakefoundshort‐termeffectsofdissolvedoxygendepletion,rapidnutrientrecycling,andreleasefollowingdeathofabloom,aswellasoccasionalfishkillsfromoxygendepletionsandcoppertoxicity.Long‐termeffectsofnearly60yearsoftreatmentincludedcopperaccumulationinsediments,growthofcopper‐tolerantalgalspecies,algalandfishpopulationshifts,lossofmacrophytes,andreductionsinbenthicmacroinvertebrates(Hanson&Stefan,1984).
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5.0 Data Gaps
Thissectionsummarizestheknowledgegapsidentifiedforthefollowingtopics:
NuisanceAlgalBloomso Cyanobacteria
Macrophytes
LiteraturereviewsanddatagapanalyseshavebeenperformedtodatebytheCyanobacteriaandMacrophyteWorkgroups.Theresultsfromthatworkhaverelevancetotheconcernsofdrinkingwaterpurveyorsregardingtheimpactsofcyanobacteriaandmacrophytesontheirconveyancefacilitiesanddrinkingwatertreatmentplants.TheliteraturereviewsperformedbytheCyanobacteriaandMacrophyteWorkgroupsfoundalackofinformationspecifictotheDelta,aswellaswhatecologicalfactorsintheDeltamaybepromotingprimaryproductivity.Tothisend,eachworkgroupwasonlyabletoanswerfullythefirstquestionposedtothem:
Provideabasicreviewofbiologicalandecologicalfactorsthatinfluencetheprevalenceofcyanobacteriaandtheproductionofcyanotoxins(CyanobacteriaWorkgroup).
Howdoessubmersedandfloatingaquaticvegetationsupportoradverselyaffecttheecosystemservicesandrelatedbeneficialuses?(MacrophyteWorkgroup).
RecommendationsforthetypesofresearchandmodelingthatareneededtobridgeexistingdatagapsareprovidedinSection6.0.
5.1 PREVALENCE OF PROBLEMS IN THE DELTA AND DOWNSTREAM CONVEYANCE AND STORAGE FACILITIES
TheprevalenceofcyanoHABsintheDeltaisnotwelldocumented,andpromptedtheCyanobacteriaWorkgrouptorecommendexpandedsurveillancemonitoringtocollectacomprehensivesetofmeasurementsthatwillassistafullevaluationoftherisktohumanhealthandaquaticlifeduetocyanotoxins,aswellastobetterunderstandthelinkagesofvariousfactorsordrivers(nutrients;temperature;highirradiance;flowasitrelatestowaterclarity,residencetime,andwatercolumnstratification;benthicgrazing;andsalinity)inpromotingandmaintainingcyanoHABs.
Similarly,theMacrophyteWorkgroupfoundthatknowledgeregardingmacrophytegrowthandbiomasstrendsintheDeltaislacking,andrecommendedexpandedsurveillancemonitoringthroughremotely‐sensedarealcoverageandfield‐basedmeasurestoestimatebiomassovertime.Monitoringwasalsorecommendedtoevaluatemacrophytespeciescommunitycompositionovertime.Similartothedataneedsofthosestudyingcyanobacteria,thereisalsoaneedtocollectinformationregardingtheeffectsoflight,temperature,salinity,flow,substratestability,chemical/mechanicalcontrol,andinterspeciescompetition.
WithrespecttocyanoHABsinStateandFederalconveyanceandstoragefacilities,asdiscussedinSection2.0,monitoringprogramsimplementedbyDWRandothershavedetectedmicrocystinin
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BarkerSloughattheNorthBayAqueductintake,CliftonCourtForebay,BanksPumpingPlant,DyerReservoirontheSBA,theGianelliandPachecointakesinSanLuisReservoir,theO’NeillForebayOutlet(Check13)ontheCaliforniaAqueduct;andinPyramidLake,CastaicLake,LakePerris,andSilverwoodLakeinSouthernCalifornia.TheextentofmonitoringperformedbydrinkingwaterpurveyorsforcyanoHABsandvariousfactorssuspectedofpromotingbloomsintheirfacilitiesisunknown,butexpandedmonitoringintheDeltaandinconveyanceandstoragefacilitieswouldcertainlyhelptoexpandtheknowledgebasetodeterminewhatmanagementactionsmaybemosthelpfulincontrollingcyanoHABsandmacrophytes.
5.2 SPATIAL AND SEASONAL OCCURRENCE OF PROBLEMS
SimilartothelackofknowledgeregardingprevalenceofcyanoHABandmacrophyteproblems,bothworkgroupsrecommendedexpandedsurveillancemonitoringasameanstobettercharacterizethespatialandseasonaloccurrencesoftheseproblems.Ingeneral,cyanoHABsarewarmseason(summerandearlyfall)phenomena,bothintheDeltaanddrinkingwaterfacilities.DuetothelackofcomprehensivemonitoringdataintheDelta,acompleteunderstandingofthespatialoccurrenceofcyanoHABshasyettobedeveloped.
ProblemscausedbyE.crassipesandE.densagrowtharemostcommoninspringthroughfallwhenthesemacrophytesgrowmostrapidly.Bothofthesenon‐nativemacrophytesoccurthroughouttheDelta,withtheircontrolbytheCaliforniaDepartmentofBoatingandWaterwayslinkedtotheirimpairmentofnavigablewaters.
Again,thespatialandseasonaloccurrenceofcyanoHABsandmacrophytesindrinkingwaterfacilitiesisunknown,butexpandedmonitoringintheDeltaandinconveyanceandstoragefacilitieswouldcertainlyhelptoenhancetheknowledgebasethatallstakeholderswillrelyupontodeterminewhatmanagementactionsmaybemosthelpfulincontrollingcyanoHABandmacrophytegrowth.
5.3 EFFECTIVENESS OF ALTERNATIVE MANAGEMENT OPTIONS ON SPECIFIC PROBLEMS
Historically,controlofmacrophytesintheDeltaanddrinkingwaterfacilitieshasbeenaccomplishedthroughapplicationofchemicals(primarily,coppersulfate)andmechanicalharvesting.Controlofalgaeindrinkingwaterfacilitieshasalsobeenconductedthroughtheapplicationofcoppersulfate.Alternativemanagementoptionsforthecontrolofspecificproblemshavenotbeenattemptedtoanygreatdegree,ifatall.Thecontrolcapabilitiesofvariousdriversaspotentialmanagementoptionshaveyettobeevaluated.TheresearchandmodelingrecommendationsinthefollowingsectionareintendedtodevelopinformationregardingthefactorsnecessarytoidentifypotentialmanagementactionsthatcanbetakentolimitcyanoHABsandthespreadandgrowthofmacrophytes.ItremainstobeseenwhethersomeorallmanagementactionsthatcouldacttolimitcyanoHABsandthespreadandgrowthofmacrophytesintheDeltacouldbeusedindrinkingwaterfacilities.
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5.4 MONITORING DATA AND PROCESS COEFFICIENTS/PARAMETERS REQUIRED FOR ECOSYSTEM AND MANAGEMENT MODELS
TheliteraturereviewsconductedbytheCyanobacteriaandMacrophyteWorkgroupsidentifiedmultipleareaswhereambientmonitoringdataandprocesscoefficients/parametersarelackingfortheDelta,andwillneedtobedevelopedthroughfuturemonitoringandresearcheffortstobestinformtheecosystemmodel(s)recommendedfordevelopment.Inadditiontoasuiteofenvironmentalparameterspinpointedformonitoring,cyanobacteriaandmacrophytegrowthrates,macrophyteturnoverrates,nutrientuptake,transformationandfluxrates,watercolumnmixingrates,andflushingrates(causingwashout)wereidentifiedasbeingnecessarytosupportecosystemmodeldevelopment(BergandSutula2015;BoyerandSutula2015).
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6.0 Recommendations for Monitoring, Research and Modeling Priorities
6.1 PROBLEM DEFINITION
Multipleknowledgegapsexistinourunderstandingoftheimportanceofnutrientprocessesanddriversthoughttoimpactcyanobacteria,cyanotoxins,tasteandodorproblems,macrophytes,andotherproblemsimpactingdrinkingwaterusesintheDeltaandinareasservedbyDeltawatersupplies.Inordertodeveloptheknowledgenecessarytobridgethegapsinourunderstandingoftheseproblems,additionalmonitoring,researchandmodelingisneeded,bothintheDeltaandindownstreamconveyanceandstoragefacilities.Futureresearchneedstobetargetedtoanswerquestionsrelatedtotheimportanceofnutrientsincombinationwithotherhydrologic,physical,biological,andchemicalfactorsinthecontroloftheidentifiedproblems.Thedevelopmentofnewinformationwillprovideamorecompleteunderstandingofthemostappropriatemanagementactions.
BoththeCyanobacteriaandMacrophyteWorkgroupsproposedanumberofmajorsciencerecommendationsgiventhedatagapsthatwereidentified.BothworkgroupsidentifiedtheneedforadditionalmonitoringintheDelta(BergandSutula2015;BoyerandSutula2015).TheCyanobacteriaWorkgrouprecommendedthedevelopmentofanecosystemmodelofprimaryproductivitytofurtherinformhypothesesonfactorscontrollingprimaryproductivityandthefutureriskofcyanoHABs(BergandSutula2015).TheMacrophyteWorkgrouprecommendedthedevelopmentofabiogeochemicalmodeloftheDeltafocusedonnutrientandorganiccarbonfateandtransport.TheMacrophyteWorkgroupalsorecommendedareviewofcurrentandpotentialfuturecontrolstrategiesforinvasivemacrophytesintheDeltathatincludesconsiderationofbarrierstoreducethemovementofvegetationintosensitiveareasorthosewithheavyhumanuse(BoyerandSutula2015).Thesemajorsciencerecommendationsshouldbesupportiveofdevelopinginitialinformationusefultoaddressingdrinkingwaterconcernsforcyanobacteriaandmacrophytes.
6.2 ROLE OF NUTRIENTS IN COMBINATION WITH OTHER FACTORS
Cyanobacteria – Cyanotoxins
MuchremainsunknownwithregardtotherolenutrientsplayininfluencingthemagnitudeandfrequencyofcyanobacteriabloomsintheDeltaanddownstreamconveyanceandstoragefacilities.AshiftinDeltaphytoplanktoncommunitycompositioninrecentyearstoincludealargerpercentageofcyanobacteria,bothtoxin‐producingandnon‐toxin‐producingstrains,currentlyaffectsdrinkingwaterduetotasteandodorproblemsandthepresenceofcyanotoxins.WecurrentlylackinformationaboutwhetheranattainablereductioninnutrientconcentrationsintheDeltacouldreducecyanobacteriabloomsandassociatedcyanotoxinproductionwithintheDeltaanddownstream.GapsinourunderstandingoftherolenutrientsplayregardingcyanobacteriabloomsintheDeltaanddownstreamfacilitiesareassociatedwithourlackofunderstandingofthe
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rolesofotherdrivers,including:temperature;irradiance;flowasitrelatestowaterclarity,residencetime,andwatercolumnstratification;benthicgrazing;andsalinity.
Expandedsystem‐widesurveillancemonitoringintheDeltaanddownstreamconveyanceandstoragefacilitiesisrecommendedtodevelopgreaterspatialandtemporalknowledgeinthefollowingareas:
Identificationoflocations,extent,timinganddurationwherecyanobacteriabloomsoccurintheDeltaandindownstreamconveyanceandstoragefacilities.DeterminationoftheriskthatcyanotoxinconcentrationsintheDeltaandinsouthofDeltareservoirsandconveyancestructuresposetodrinkingwaterduetophysicalproximity.
Measurementofenvironmentalfactors(e.g.,nutrients,temperature,irradiance,turbidity,flow,andsalinity)thatco‐occurwithdifferentstagesofbloomdevelopmenttogainanunderstandingofthepresenceandmagnitudeofthedriversthatinfluencebloominitiation,bloommagnitude,andcyanotoxinproduction.Monitoringshouldincludeinstantaneous,annual,andinter‐annualmeasurements.
Fieldandlaboratorystudiesarealsorecommendedtoprovideinsighttowhetherthedriversthatinfluencecyanobacteriabloomscanbemanaged,andwhateffectthecontrolofthesefactorshasoncyanobacteriabloommagnitudeandduration.Studiesarerecommendedinthefollowingareas:
Initiationoflaboratoryandfieldstudiesduringbloomstodeterminewhethermodificationofnutrientconcentrationscanreducethemagnitudeandfrequencyofcyanobacteriablooms(andassociatedtoxinlevels)intheDeltaanddownstreamfacilities.
Investigationoftheeffectsthatotherkeyfactors(e.g.,temperature,turbidity,mixingrates,andflow(causingwash‐out))haveonbloomformationandattenuation.
Cyanobacteria – Taste and Odors
Theroleofnutrientconcentrationsininfluencingtheoccurrence,magnitude,anddurationoftasteandodorepisodesintheDeltaandindownstreamconveyancefacilitiesandreservoirsisnotwellunderstood.Wecurrentlylackinformationabouttheformsandconcentrationsofnutrientsthatinfluencethegrowthofthespeciesofbenthicandplanktoniccyanobacteriathatcausetasteandodorproblems.Finally,gapsexistinourunderstandingoftherolesofotherfactorsontheoccurrenceanddurationoftheseepisodes,includingtemperature;lightlevels;waterclarity;waterresidencetime;waterstratification;andotherfactorsthatinfluencealgalcommunitycompositionandtheproductionofcompoundsresponsiblefortasteandodorproblems.
Expandedsurveillancemonitoring,modeling,andanalysisofavailabledataintheDeltaandindownstreamconveyanceandstoragefacilitiesisrecommended,asfollows:
Performanceofmicrobialsurveysand/orspeciesstudiestoexpandourknowledgeoftheprevalenceofproblematicbenthicandplanktoniccyanobacteriaspecies,thedriversthatpromotetheirgrowth,andwhattheirpotentialcontributiontotasteandodorepisodes
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mightbe.Assessimpactsofbenthicspeciesascomparedtothebetterstudiedplanktoniccyanobacteriaspecies.
SynthesizeavailabledatatoidentifyspatialandtemporaloccurrenceoftasteandodorproblemsinthewatersupplyconveyancefacilitiesdownstreamoftheDelta.Determineifmodificationstomonitoring,suchasfocusedmonitoringduringblooms,wouldenhancethequalityofthedataandunderstandingofbloomdistributionsinthesefacilities.
PerformmonitoringandmodelingtounderstandthemagnitudeandimportanceofsourcesofnitrogenandphosphorusintheDelta,withconsiderationforDeltahydrodynamics,variableDeltaflowconditions,nutrienttransformations,tributaryinputs,sedimentflux,etc.aspartofanassessmentoftheroleofnutrientsintasteandodorproblemoccurrenceandcontrol.ThiseffortshouldincludeanalysisoftheDWRMWQIenhancedmonitoringforNandPdatathatwascollectedtoprovideinputstotheDSM2waterqualitymodelandanalysisofhistoricalMWQImonitoringofDeltaIslanddischarges.
FieldandlaboratorystudiesarealsorecommendedtoprovideinsightintothepossiblemanagementoftasteandodorproblemsintheDeltaandindownstreamfacilities.Studiesarerecommendedinthefollowingareas:
Measurementofenvironmentalfactors(e.g.,nutrients,temperature,irradiance,turbidity,flow,andsalinity)thatco‐occurwithdifferentstagesoftasteandodor‐producingcyanobacteriabloomdevelopmentindownstreamwatersupplyfacilities.Investigationoftheeffectsthatturbidity,mixingrates,andflow(causingwash‐out)haveontasteandodorepisodeinitiationandattenuation.
Insitustudiesinreservoirsandconveyancefacilitiestoisolatetheincrementalimpactofchangesinnutrientwatercolumnconcentrationsonproliferationofplanktonicandbenthiccyanobacteriaspeciesresponsiblefortasteandodorepisodes.DeterminationoftheeffectthatambientnutrientconcentrationreductionswillhaveontasteandodoroccurrencesdownstreamofDeltainreservoirsandconveyancestructures.Theuseof“Limnocorrals6”wassuggestedasoneidea.Notethatalimitationintheuseof“limnocorrals”isthattheyreduceturbulenceandquicklychangethelightclimate.
Macrophytes
SimilaritiesexistbetweencyanobacteriaandmacrophytebloomswithregardtoourlackofknowledgeabouttheextentofthemacrophyteproblemintheDeltaanddownstreamconveyanceandstoragefacilities.Questionsalsoexistregardingthedegradationofwaterqualityandimpactstobeneficialuses,driversthataremostinfluentialinpromotingthegrowthofinvasiveandnative
6Alimnocorral(orlimnocorral,limno‐corral)isanenclosurethatextendsfromthewatersurfacetothesediment,whereitisanchored,thatallowsadefinedvolumeofwatertobephysicallyseparatedfromthesurroundingwaterbody.
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macrophytes,andwhichofthesedriverscanbecontrolledthroughmanagementactions.Aswithcyanobacteria,therolethatnutrients(viaforms,concentrations,andtiming)playinstimulatingmacrophytegrowthintheDeltaanddownstream–especially,asitinfluencesthegrowthofinvasive,non‐nativespecies,suchasE.crassipesandE.densa–isnotcompletelyunderstood,noristheimpactthatotherfactors(light,temperature,salinity,flow,substratestability,chemical/mechanicalcontrol,andinterspeciescompetition)haveonthespreadandgrowthofmacrophytesintheDeltaanddownstreamconveyanceandstoragefacilities.Ofgreatestinteresttodrinkingwatermanagersistheabilitytocontrolthespreadandgrowthofmacrophytesinreservoirsandconveyancestructuresinareaswheresuchgrowthclogspumpsandfiltersandimpedesflows.ExpandingsurveillancemonitoringintheDeltaanddownstreamfacilitiesisrecommendedtodevelopgreaterknowledgeinthefollowingareas:
DeterminationoftheextentofinvasiveaquaticplantbloomsintheDeltaandindownstreamconveyanceandstoragefacilities,aswellasthedetectionofnewinvasionsthroughimplementationofacomprehensivemulti‐yearmonitoringprogram.
Measurementofenvironmentalfactorsandphysicalconditions(e.g.,nutrients,temperature,light,turbidity,flow,andsalinity)thatco‐occurwithnativeandnon‐nativemacrophytestogainanunderstandingofthepresenceandmagnitudeoffactorsthatco‐occurwithandinfluencemacrophytegrowthintheDeltaandindownstreamfacilities.Monitoringshouldincludeinstantaneous,annual,andinterannualmeasurements.
Fieldandlaboratorystudiesarealsorecommendedtoprovideinsightintothemanagementofdriversthatinfluencemacrophytegrowth,andtowhateffectthecontrolofthesefactorshasonmacrophytegrowth.Studiesarerecommendedinthefollowingareas:
DeterminationoffieldmethodsforrapidlyassessinginsitunutrientlimitationofmacrophytesintheDeltaandindownstreamfacilities.Conductlaboratoryculturestudiestoevaluategrowthrateasafunctionofambientnutrientconcentrationsinwaterandsediment.Analyzetissuenutrientconcentrationstodeterminetherelationshipbetweentissuegrowth,nutrientuptakerates,andnutrientconcentrations.Confirmrelationshipsinfieldtrials.
Ifnutrientreductionsareshowntosufficientlylimitmacrophytegrowthandsuchreductionscanbeachievedthroughthecontrolofpointsources,useofmesocosmstudiestodetermineifmechanicalandchemicalcontrolofmacrophytesisenhancedbynutrientreductions.
6.3 MODELING TOOLS AND SCENARIOS
Development of Modeling Tools
ThecomplexnatureoftheDeltaecosystemandtherangeofquestionsforwhichanswersaresoughtregardingthefactorsthatinfluencephytoplankton,cyanobacteria,andmacrophytegrowthrequiretheabilitytocharacterizemultipleprocessesintheformofamodelormodels.ThecollectionandanalysisofempiricaldataalonewillnotprovidetheabilitytotestfutureDelta
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managementscenarios.TheModelingScienceWorkgroupidentifiedfourreasonswhymodelswillprovidevaluabletoolsformanagingwaterqualityintheDelta(Trowbridgeetal.,2015):
TheDeltaistoocomplextocomprehensivelyunderstandwithoutmodels.Empiricaldatacollectioncannotbeachievedatthespatialandtemporalscalesnecessarytofullycharacterizeandtestpotentialmanagementactions.
Modelscanprovideinsightintotheecologicalsignificanceofnutrientchangesfromanecosystemperspective.
Modelscanefficientlyallowstakeholderstodevelopandassessmanagementscenariostocharacterizetheeffectofnutrientsoverarangeofconditions.
Modelscanbeeffectiveforcommunicatingimportantinformationtostakeholders,regulators,andresourcemanagers,leadingtoacommonunderstandingofcomplexsystems.
FuturemodelingeffortsmustconsiderasuiteofimportantprocessesthatoperatesimultaneouslyintheDelta,includinghydrodynamics,nutrientconcentrations,otherwaterqualityconditions,primaryproductivity,benthicandpelagicgrazing,sedimenttransport,andothercyanobacteriaandmacrophyte‐relatedprocesses.AconsiderationofthesefactorsandtheirinteractionswillalsoprovideinsightintohowachangeinagivendriverordriverscouldaffectcyanobacteriaandmacrophytebloomsintheDelta.Throughtheuseofmodelingscenariosandsensitivityanalysis,itwillbepossibletogainanunderstandingofhowchangesinnutrientconcentrationsandforms,aswellasotherdrivers,mayimpactdrinkingwaterproblemsassociatedwithcyanobacteriaandmacrophytes.
Modeling Scenarios
Thedevelopmentofmodelingtoolstoanswernutrientmanagementquestionsisplannedtooccurintwophases.Theinitialphaseisanticipatedtobecompletedby2020or2021.ThistimeframecoincideswithexpectedchangesinthedischargeofnutrientsintotheLowerSacramentoRiverfromtheSacramentoRegionalWastewaterTreatmentPlant(SRWTP),thedischargeofnutrientsfromtheCitiesofModestoandTurlockintotheLowerSanJoaquinRiverduetotheredirectionoftheirflowstotheDeltaMendotaCanal,andthedischargeofnutrientsfromtheCityofStocktonwastewatertreatmentplantintotheSanJoaquinRiverduetotheimplementationofnewnutrientremovalprocesses(LWA2017).FuturemodelingoftheDeltaecosystemwillneedtoconsiderabaselineconditionwithrespecttonutrientinputsfromtheLowerSacramentoRiver,theLowerSanJoaquinRiver,andtheSanJoaquinRiverthatvariesfromcurrentconditions.ModelingeffortswillalsoneedtoconsideramultitudeofphysicalandbiologicalchangesexpectedtooccuriftheprojectsproposedaspartoftheBayDeltaConservationPlanareimplemented.FutureexpandedsurveillancemonitoringandresearchcomingfromimplementationoftheDeltaNutrientResearchPlanwillprovideadditionalempiricaldataandarefinedmechanisticunderstandingofDeltaprocessesthatwillneedtobeincorporatedintomodelingtools.
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Onceinformationgathering,research,andmodeldevelopmenteffortsaresufficienttobeginassessingchangesinbaselineconditionsthroughspecificmanagementactions,itwillbeimportantthatmodelingscenariosappropriatelyconsiderfuturechangesinclimate,Deltahydrology,wetlandrestoration,andnutrientloading.Itwillbenecessarytodevelopmodelingscenariosthatconsiderplanned,possible,andouterboundarychangesthatcanbeproducedthroughvaryinglevelsofnutrientloadmanagementandsystemmanagement.
6.4 EFFECTIVENESS OF MANAGEMENT
Asmodeldevelopmentmatures,andmodelingscenariosarecreatedthatshowprojectedoutcomesofvariousmanagementactions,itwillbeimportanttoconsiderthefollowingaspectsofsuchmanagementactions:
Canreductionsinnutrientloadsalone,orincombinationwithothermanagementefforts,limitthegrowthandproliferationofcyanobacteriaandnon‐nativemacrophytesand,thereby,preventorsignificantlyreducetasteandodor,cyanotoxinand/ormacrophyteproblemsintheDeltaandindownstreamstorageandconveyancefacilities?
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7.0 Literature Cited
Alpine,A.E.,J.E.Cloern.(1992).Trophicinteractionsanddirectphysicaleffectscontrolphytoplanktonbiomassandproductioninanestuary.LimnologyandOceanography37(5):946‐955.Anderson,L.W.J.2003.AreviewofaquaticweedbiologyandmanagementresearchconductedbytheUnitedStatesDepartmentofAgriculture—AgriculturalResearchService.PestManagementScience59:801–813.ArchibaldConsulting,PalenciaConsultingEngineers,StarrConsulting.(2012).CaliforniaStateWaterProjectWatershedSanitarySurvey,2011Update.http://www.water.ca.gov/waterquality/drinkingwater/docs/Printerscopycombin.pdfBaker,L.A.,P.Westerhoff,M.Sommerfeld.(2006).Adaptivemanagementusingmultiplebarrierstocontroltastesandodors.J.Am.Wat.WorksAssoc.98:113–126.Berg,M.andM.Sutula.(2015).FactorsaffectingthegrowthofcyanobacteriawithspecialemphasisontheSacramento‐SanJoaquinDelta‐Draft.SouthernCaliforniaCoastWaterResearchProjectTechnicalReportNo.869.CostaMesa,CA.July.Borgnis,E.andK.E.Boyer.Inpress.SalinitytoleranceandcompetitiondrivedistributionsofnativeandinvasivesubmergedaquaticvegetationintheupperSanFranciscoEstuary.EstuariesandCoasts.Boyd,P.W.,T.A.Rynearson,E.A.Armstrongetal.(2013).Marinephytoplanktontemperatureversusgrowthresponsesfrompolartotropicalwaters–outcomeofascientificcommunity‐widestudy.PLoSONE8(5):e63091doi:10.1371/journal.pone.0063091.Boyer,K.andM.Sutula.(2015).FactoringControllingSubmersedandFloatingMacrophytesintheSacramento‐SanJoaquinDelta–Draft.SouthernCaliforniaCoastalWaterResearchProject.TechnicalReportNo.870.CostaMesa,CA.November.Burlingame,G.A.,R.M.Dann,G.L.Brock.(1986).AcasestudyofgeosmininPhiladelphia’swater.J.Am.Wat.WorksAssoc.78:56–61.Butterwick,C.,S.I.Heaney,J.F.Talling.(2005).Diversityintheinfluenceoftemperatureonthegrowthratesoffreshwateralgae,anditsecologicalrelevance.FreshwaterBiology50:291‐300.Brenda,G.,Madsen,J.,Pratt,P.(2015).Landscape‐LevelAssessmentandManagementofInvasiveWeedsandtheirImpactsinAgriculturalandNaturalSystems.2015AnnualReport.https://www.ars.usda.gov/research/project/?accnNo=421093&fy=2015
DeltaNutrients–DrinkingWaterIssues 50 June20,2017
Carey,C.C.,B.W.Ibelings,E.P.Hoffmann,D.P.Hamilton,J.D.Brookes.(2012).Eco‐physiologicaladaptationsthatfavourfreshwatercyanobacteriainachangingclimate.WaterResearch46:1394‐1407.Cavalli,G.,T.Riis,A.Baattrup‐Pedersen.(2012).Bicarbonateuseinthreeaquaticplants.AquaticBotany98:57‐60.CentralValleyDrinkingWaterPolicyWorkgroup.(2012).SynthesisReport.February21.CentralValleyRegionalWaterQualityControlBoard(CVRWQCB).2013.DraftStrategyfordevelopinganutrientresearchplanfortheDelta.February.http://www.waterboards.ca.gov/centralvalley/water_issues/delta_water_quality/delta_nutrient_research_plan/2013_0219_nutrient_strategy_draft.pdfCloern,J.E.(2001).Ourevolvingconceptualmodelofthecoastaleutrophicationproblem.Mar.Ecol.Prog.Ser.210:223–253.Cole,B.E.,J.E.Cloern.(1984).SignificanceofbiomassandlightavailabilitytophytoplanktonproductivityinSanFranciscoBay.MarineEcologyProgressSeries17:15‐24.Cole,B.E.,J.E.Cloern.(1987).Anempiricalmodelforestimatingphytoplanktonproductivityinestuaries.MarineEcologyProgressSeries36:299‐305.ContraCostaWaterDistrict.2010.HistoricalfreshwaterandsalinityconditionsinthewesternSacramento‐SanJoaquinDeltaandSuisunBay:Asummaryofhistoricalreviews,reports,analysesandmeasurements.WaterResourcesDepartment,ContraCostaWaterDistrict,Concord,California,TechnicalMemorandumWR10‐001.DeltaStewardshipCouncil.(2013).TheDeltaPlan:EnsuringaReliableWaterSupplyforCalifornia,aHealthyDeltaEcosystem,andaPlaceofEnduringValue.http://deltacouncil.ca.gov/delta‐plan‐0DepartmentofWaterResources.(2013).AquaticPesticidesApplicationPlan.http://www.water.ca.gov/swp/waterquality/docs/DWR_2013_APAP_Final.pdfElliott,J.A.(2010).Theseasonalsensitivityofcyanobacteriaandotherphytoplanktontochangesinflushingrateandwatertemperature.GlobalChangeBiology16:864‐876.Fleck,J.A.,Bossio,D.A.,Fujii,R.(2004).Dissolvedorganiccarbonanddisinfectionby‐productprecursorreleasefrommanagedpeatsoils.JEnvironQual33(2):465‐475.Glibert,P.M.(2010).Long‐termchangesinnutrientloadingandstoichiometryandtheirrelationshipswithchangesinthefoodwebanddominantpelagicfishspeciesintheSanFranciscoEstuary,California.ReviewsinFisheriesScience18:211‐232.
DeltaNutrients–DrinkingWaterIssues 51 June20,2017
GlibertP.M.,D.Fullerton,J.M.Burkholder,J.C.Cornwell,T.M.Kana.(2011).Ecologicalstoichiometry,biogeochemicalcycling,invasivespecies,andaquaticfoodwebs:SanFranciscoEstuaryandcomparativesystems.RevFishSci19:358‐417GlibertP.M.,R.C.Dugdale,F.Wilkerson,A.E.Parker,J.Alexander,E.Antell,S.Blaser,A.Johnson,J.Lee,T.Lee,S.Murasko,andS.Strong.(2014).Major–butrare‐springbloomsin2014inSanFranciscoBayDeltaCalifornia,aresultofthelong‐termdrought,increasedresidencetime,andalterednutrientloadsandforms.JournalofExperimentalMarineBiologyandEcology460:8‐18.Greenfield,B.K.,G.S.Siemering,J.C.Andrews,M.Rajan,S.P.AndrewsJr.,andD.F.Spencer.(2007).Mechanicalshreddingofwaterhyacinth(Eichhorniacrassipes):EffectsonwaterqualityintheSacramento‐SanJoaquinRiverDelta,California.EstuariesandCoasts30:627‐640.Haller,W.T.,D.L.Sutton,W.C.Barlowe.(1974).Effectsofsalinityongrowthofseveralaquaticmacrophytes.Ecology55:891‐894.Hanson,M.J.,H.G.Stefan.(1984)Sideeffectsof58yearsofcoppersulfatetreatmentoftheFairmontLakes,Minnesota.WaterResourcesBulletin20(6):889‐900.DOI:10.1111/j.1752‐1688.1984.tb04797.x.Hestir,E.L.,D.H.Schoellhamer,T.Morgan‐King,S.L.Ustin.(2013).Astepdecreaseinsedimentconcentrationinahighlymodifiedtidalriverdeltafollowingthe1983ElNiñofloods.MarineGeology345:304‐313.HuismanJ,R.R.Jonker,Zonneveld,C,F.J.Weissing.(1999).Competitionforlightbetweenphytoplanktonspecies:experimentaltestsofmechanistictheory.Ecology80:211‐222HuismanJ.,J.Sharples,J.Stroometal.(2004).Changesinturbulentmixingshiftcompetitionforlightbetweenphytoplanktonspecies.Ecology85:2960‐2970.Izaguirre,G.,C.J.Hwang,S.W.Krasner.(1984).Investigationsintothesourceof2‐methylisoborneolinLakePerris,California.Proc.11thAnn.Wat.Qual.Technol.Conf.,4‐7Dec.1983,Norfolk,Virginia.AmericanWaterWorksAssociation,Denver,Colorado.Izaguirre,G.,W.D.Taylor.(1995).Geosminand2‐methylisoborneolproductioninamajoraqueductsystem.Wat.Sci.Technol.31:41‐48.Izaguirre,G.,W.D.Taylor.(1998).APseudanabaenaspeciesfromCastaicLake,California,thatproduces2‐methylisoborneol.Wat.Res.32:1673‐1677.Jassby,A.D.,J.E.Cloern,B.E.Cole.(2002).Annualprimaryproduction:patternsandmechanismsofchangeinanutrientrichtidalecosystem.LimnologyandOceanography47:698–712.
DeltaNutrients–DrinkingWaterIssues 52 June20,2017
Jassby,A.(2008).PhytoplanktonintheUpperSanFranciscoEstuary:RecentBiomassTrends,theircauses,andtheirtrophicsignificance.SanFranciscoEstuaryandWatershedScience6(1).http://escholarship.org/uc/item/71h077rlJuttner,F.(1984).CharacterizationofMicrocystisstrainsbyalkylsulfidesandbetacyclocitral.Z.Naturforsch.Sect.CJ.Biosci.39:867–871.Juttner,F.,B.Hoflacher,K.Wurster.(1986).Seasonalanalysisofvolatileorganicbiogenicsubstances(VOBS)infreshwaterphytoplanktonpopulationsdominatedbyDinobryon,Microcystis,andAphanizomenon.J.Phycol.22:169–175.doi:10.1111/j.1529‐8817.1986.tb04160.x.Juttner,F.,S.B.Watson.(2007).Biochemicalandecologicalcontrolofgeosminand2‐methylisoborneolinsourcewaters.Appl.Environ.Microbiol.73:4395–4406.doi:10.1128/AEM.02250‐06.PMID:17400777.Kimmerer,W.J.,A.E.Parker,U.E.Lidstrom,E.J.Carpenter.(2012).Short‐termandinterannualvariabilityinprimaryproductioninthelow‐salinityzoneoftheSanFranciscoEstuary.EstuariesandCoasts35:913‐929.Knobeloch,L.,Salna,B.,Hogan,A.,Postle,J.,andAnderson,H.2000.Bluebabiesandnitrate‐contaminatedwellwater.EnvironHealthPerspect108(7):675‐678.Knowles,N.,D.R.Cayan.(2002).PotentialeffectsofglobalwarmingontheSacramento/SanJoaquinwatershedandtheSanFranciscoestuary.GeophysicalResearchLetters29:38‐1–38‐4.Kudo,I.,M.Miyamoto,Y.Noiri,Y.Maita.(2000).CombinedeffectsoftemperatureandirononthegrowthandphysiologyofthemarinediatomPhaeodactylumtricornutum(Bacillariophyceae).JPhycol36:1096‐1102.LarryWalkerAssociates(LWA).(2015).NandPDataGraphsforDeltaStations.DevelopedbyLarryWalkerAssociatesforUsebytheDeltaNNEScienceWorkGroups.July29.LarryWalkerAssociates(LWA).(2017).ProjectedNutrientLoadReductionstotheSacramento‐SanJoaquinDeltaAssociatedwithChangesatFourPOTWs.MemorandumpreparedbyLarryWalkerAssociatesforTerrieMitchell,SacramentoRegionalCountySanitationDistrict.January25.LeeG.F.andA.Jones‐Lee.(2006).NutrientrelatedwaterqualityconcernsintheSacramentoandSanJoaquinRiversandDelta.ReportofG.FredLee&Associates,ElMaceroCA.Lehman,P.W.,G.Boyer,C.Hall,S.Waller,K.Gehrts.(2005).DistributionandtoxicityofanewcolonialMicrocystisaeruginosabloomintheSanFranciscoBayEstuary,California.Hydrobiologia541:87‐99.
DeltaNutrients–DrinkingWaterIssues 53 June20,2017
LehmanP.W.,G.Boyer,M.Satchwell,S.Waller.(2008).TheinfluenceofenvironmentalconditionsontheseasonalvariationofMicrocystiscelldensityandmicrocystinsconcentrationinSanFranciscoEstuary.Hydrobiologia600:187‐204.Lurling,M.,F.Eshetu,E.J.Faassen,S.Kosten,V.M.Huszar.(2013).Comparisonofcyanobacterialandgreenalgalgrowthratesatdifferenttemperatures.FreshwaterBiology58:552‐559.Mioni,C.,R.Kudela,D.Baxa.(2012).HarmfulcyanobacteriabloomsandtheirtoxinsinClearLakeandtheSacramento‐SanJoaquinDelta(California).SurfaceWaterAmbientMonitoringProgramReport10‐058‐150.110pp.Moisander,P.H.,E.McClinton,H.W.Pearl.(2002).Salinityeffectsongrowth,photosyntheticparameters,andnitrogenaseactivityinestuarineplanktoniccyanobacteria.MicrobEcology43:432‐442.Moyle,P.B.,W.A.Bennett,W.E.Fleenor,J.R.Lund.(2010).HabitatvariabilityandcomplexityintheupperSanFranciscoEstuary.SanFranciscoEstuaryandWatershedScience8(3).Muramoto,S.,I.Aoyama,andY.Oki.(1991).Effectofsalinityontheconcentrationofsomeelementsinwaterhyacinth(Eichhorniacrassipes)atcriticallevels.JEnvironSciHealthA26:205–15.Nicholls,K.H.(1995).Chrysophytebloomsintheplanktonandneuston.pp.181–215.InC.Sandgren,J.Smol,andJ.Kristiansen[eds.]Chrysophytealgae:ecology,phylogenyanddevelopment.CambridgeUniversityPress,Cambridge,UK.Olivares,E.,G.Colonnello.(2000).SalinitygradientintheMa´namoRiver,adammeddistributaryoftheOrinocoDelta,anditsinfluenceonthepresenceofEichhorniacrassipesandPaspalumrepens.Interciencia25:242–248.Paerl,H.W.,J.Huisman.(2008).Bloomslikeithot.Science320:57‐58.Reynolds,C.S.(1999).Non‐determinismtoprobability,orN:Pinthecommunityecologyofphytoplankton.ArchHydrobiol146:23‐35.Reynolds,C.S.(2006).EcologyofPhytoplankton.CambridgeUniversityPress,Cambridge.Robarts,R.D.,T.Zohary.(1987).Temperatureeffectsonphotosyntheticcapacity,respirationandgrowthratesofphytoplanktonofbloom‐formingcyanobacteria.NZJMarFreshwatRes21:391‐401.Rodrigues,R.B.andS.M.Thomaz.(2010).PhotosyntheticandgrowthresponsesofEgeriadensatophotosyntheticactiveradiation.AquaticBotany92:281‐284.
DeltaNutrients–DrinkingWaterIssues 54 June20,2017
Roelke,D.L.,S.Augustin,Y.Buyukates.(2003).Fundamentalpredictabilityinmultispeciescompetition:Theinfluenceoflargedisturbance.AmNat162:615‐623.Romo,A.,J.Soria,F.Fernandez,Y.Ouahid,A.Baron‐sola.(2013).Waterresidencetimeandthedynamicsoftoxiccyanobacteria.FreshwaterBiology58:513‐522.Sacramento‐SanJoaquinDelta–Draft.ReportpreparedfortheCentralValleyRegionalWaterQualityControlBoard.ReportpreparedbyModelingScienceWorkgoup.October21.Sand‐Jensen,K.(1989).Environmentalvariablesandtheireffectonphotosynthesisofaquaticplantcommunities.AquaticBotany34:5‐25.Santamaría,L.(2002).Whyaremostaquaticplantswidelydistributed?Dispersal,clonalgrowthandsmall‐scaleheterogeneityinastressfulenvironment.ActaOecologica23:137–154.Saker,M.L.,B.A.Neilan.(2001).Varieddiazotrophies,morphologies,andtoxicitiesofgeneticallysimilarisolatesofCylindrospermopsisraciborskii(Nostocales,Cyanophyceae)fromnorthernAustralia.ApplMicrobiol67:1839‐1845.Schoellhamer,D.H.(2011).Suddenclearingofestuarinewatersuponcrossingthethresholdfromtransporttosupplyregulationofsedimenttransportasanerodiblesedimentpoolisdepleted:SanFranciscoBay,1999.EstuariesandCoasts34:885–899.Spencer,D.F.,G.G.Ksander,M.J.Donovan,P.S.Liow,W.K.Chan,B.K.Greenfield,S.B.Shonkoff,andS.P.Andrews.2006.EvaluationofwaterhyacinthsurvivalandgrowthintheSacramentoDelta,California,followingcutting.JournalofAquaticPlantManagement44:50‐60.Stewart,R.M.,A.F.Cofrancesco,andL.G.Bezark.1988.BiologicalcontrolofwaterhyacinthintheCaliforniaDelta.U.S.ArmyCorpsofEngineersWaterwaysExperimentStation,TechnicalReportA‐88‐7.U.SArmyCorpsofEngineers,Washington,D.C.Sugiura,N.,N.Iwami,Y.Inamori,O.Nishimura,R.Sudo.(1998).SignificanceofattachedcyanobacteriarelevanttotheoccurrenceofmustyodorinLakeKasumigaura.Wat.Res.32:3549–3554.Sunda,W.G.,D.R.Hardison.(2007).Ammoniumuptakeandgrowthlimitationinmarinephytoplankton.LimnolOceanogr52:2496‐2506.TetraTech.(2006).NutrientintheCentralValleyandSacramento‐SanJoaquinDelta.UnitedStatesEnvironmentalProtectionAgency,Region9.http://www.waterboards.ca.gov/centralvalley/water_issues/drinking_water_policy/final_nutrient_report_lowres.pdf
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Tett,P.,S.I.Heaney,M.R.Droop.(1985).TheRedfieldratioandphytoplanktongrowthrate.JMarBiolAssUK65:487‐504.Tilman,D.,S.S.Kilham,P.Kilham.(1982).Phytoplanktoncommunityecology:theroleoflimitingnutrients.AnnlsRevEcolSyst13:349‐372.Tonk,L.,K.Bosch,P.M.Visser,J.Huisman.(2007).SalttoleranceoftheharmfulcyanobacteriumMicrocystisaeruginosa.AquatMicrobEcol46:117‐123.Trowbridge,P.R.,M.Deas,E.Ateljevich,E.Danner,J.Domagalski,C.Enright,W.Fleenor,C.Foe,M.Guerin,D.Senn,andL.Thompson.(2015).DraftFinalModelingScienceWorkgroupWhitePaper:RecommendationsforaModelingFrameworktoAnswerNutrientManagementQuestionsintheSacramento‐SanJoaquinDelta.October21.Tung,S.,T.Lin,F.Yang,C.Liu.(2008).Seasonalchangeandcorrelationwithenvironmentalparametersfor2‐MIBinFeng‐ShenReservoir,Taiwan.Environ.Monit.Assess.145:407‐416.doi:10.1007/s10661‐007‐0049‐9.UnitedStatesEnvironmentalProtectionAgency.(2002).Nitrification.http://water.epa.gov/lawsregs/rulesregs/sdwa/tcr/upload/nitrification.pdfUnitedStatesEnvironmentalProtectionAgency.(2012).Cyanobacteriaandcyanotoxins:informationfordrinkingwatersystems.http://water.epa.gov/scitech/swguidance/standards/criteria/nutrients/upload/cyanobacteria_factsheet.pdfUnitedStatesEnvironmentalProtectionAgency.(2015a).DrinkingWaterHealthAdvisoryfortheCyanobacterialToxinCylindrospermopsin.http://www2.epa.gov/sites/production/files/2015‐06/documents/cylindrospermopsin‐report‐2015.pdfUnitedStatesEnvironmentalProtectionAgency.(2015b).2015DrinkingWaterHealthAdvisoriesforTwoCyanobacterialToxins.http://www2.epa.gov/sites/production/files/2015‐06/documents/cyanotoxins‐fact_sheet‐2015.pdfUnitedStatesEnvironmentalProtectionAgency.Undated.ContaminantCandidateListandRegulatoryDetermination.http://www2.epa.gov/ccl/chemical‐contaminants‐ccl‐4Uwins,H.K.,P.Teasdale,H.Stratton.(2007).Acasestudyinvestigatingtheoccurrenceofgeosminand2‐methylisoborneol(MIB)inthesurfacewatersoftheHinzeDam,GoldCoast,Australia.WaterSci.Technol.55:231‐238.
DeltaNutrients–DrinkingWaterIssues 56 June20,2017
Watson,S.B.,McCauley,E.,J.A.Downing.(1997).Patternsinphytoplanktontaxonomiccompositionacrosstemperatelakesofdifferingnutrientstatus.Limnol.Oceanogr.42:486–495.Watson,S.B.,T.Satchwill,E.McCauley.(2001a).Drinkingwatertasteandodor:achrysophyteperspective.NovaHedwigia122:119–146.Watson,S.B.,T.Satchwill,E.McCauley.(2001b).Under‐icebloomsandsource‐waterodourinanutrient‐poorreservoir:biological,ecologicalandappliedperspectives.Freshw.Biol.46:1–15.doi:10.1046/j.1365‐2427.2001.00769.x.Watson,S.B.,J.Ridal.(2004).Periphyton:aprimarysourceofwidespreadandseveretasteandodour.Wat.Sci.Tech.49:33–39.Watson,S.B.,M.Charlton,Y.R.Rao,T.Howell,J.Ridal,B.Brownlee,C.Marvin,S.Millard.(2007).Offflavoursinlargewaterbodies:physics,chemistryandbiologyinsynchrony.WaterSci.Technol.55:1‐18.Watson,S.B.,J.Ridal,G.L.Boyer.(2008).Tasteandodourandcyanobacterialtoxins:impairment,prediction,andmanagementintheGreatLakes.Can.J.Fish.Aquat.Sci.65:1779‐1796/doi:10.1139/F08‐084.WestYostAssociates.(2011).WastewaterControlMeasuresStudy.http://www.waterboards.ca.gov/centralvalley/water_issues/drinking_water_policy/dwp_wastewtr_cntrl_meas_stdy.pdfWilkerson,F.P.,R.C.Dugdale,V.E.Hogue,A.Marchi.(2006).PhytoplanktonbloomsandnitrogenproductivityinSanFranciscoBay.EstuariesandCoasts29:401–416.WrightandSchoellhamer.(2004).SanFranciscoEstuaryandWatershedScience(2)2.Wu,Z.,J.Shi,R.Li.(2009).ComparativestudiesonphotosynthesisandphosphatemetabolismofCylindrospermopsisraciborskiiwithMicrocystisaeruginosaandAphanizomenonflos‐aquae(2009).HarmfulAlgae8:910‐915.Yano,H.,M.Nakahara,H.Ito.(1988).WaterbloomsofUroglenaamericanaandtheidentificationofodorouscompounds.WaterSci.Technol.20:75–80.Yen,H.,T.Lin,S.Tung,M.Hsu.(2007).Correlating2‐MIBandmicrocystinconcentrationswithenvironmentalparametersintworeservoirsinsouthTaiwan.WaterSci.Technol.55:33‐41.Yoshimasa,Y.,H.Nakahara.(2005).TheformationanddegradationofcyanobacteriumAphanizomenonflos‐aquaeblooms:theimportanceofpH,watertemperature,anddaylength.Limnology6:1‐6.
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Zaitlin,B.,S.B.Watson,J.Ridal,T.Satchwill,D.Parkinson.(2003).ActinomycetesinLakeOntario:habitatsandproductionofgeosminand2‐methylisoborneol.J.Am.WaterWorksAssoc.95(2),113–118.Zaitlin,B.,S.B.Watson.(2006).Actinomycetesinrelationtotasteandodourindrinkingwater:myths,tenetsandtruths.WaterRes.40:1741–1753.doi:10.1016/j.watres.2006.02.024.PMID:16600325.
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Appendix A
A.1 THE STATE WATER PROJECT
TheSWPextendsfromthemountainsofPlumasCountyintheFeatherRiverwatershedtoLakePerrisinRiversideCounty.WaterfromthenorthDeltaispumpedintotheNorthBayAqueduct(NBA)attheBarkerSloughPumpingPlant,asshowninFigureA.1.BarkerSloughisatidallyinfluenceddead‐endsloughwhichistributarytoLindseySlough.LindseySloughistributarytotheSacramentoRiver.Thepumpingplantdrawswater fromboth theupstreamBarkerSloughwatershedand from theSacramentoRiver,viaLindseySlough.OtherlocalsloughsmayalsocontributewatertotheNBA.TheNBApipelineextends21milesfromBarkerSloughtoCordeliaForebay(Cordelia)andPumpingPlant,andthen7milestoitsterminusattwo5‐milliongallonterminaltanks.TheNBAservesasamunicipalwatersupplysourceforanumberofmunicipalitiesinSolanoandNapacounties.TheSolanoCountyWaterAgency(SCWA)andtheNapaCountyFloodControlandWaterConservationDistrict(NapaCounty)arewholesalebuyersofwaterfromtheSWP.SCWAdeliverswatertoTravisAirForceBaseandthecitiesofBenicia,Fairfield,Vacaville,andVallejo.NapaCountydeliverswatertothecitiesofNapa,andAmericanCanyon.
InthesouthernDelta,waterentersSWPfacilitiesatCliftonCourtForebay(CliftonCourt),andflowsacross the forebayabout3miles to theH.O.BanksDeltaPumpingPlant (Banks), fromwhich thewaterflowssouthwardintheGovernorEdmundG.BrownCaliforniaAqueduct(CaliforniaAqueduct).WaterisdivertedintotheSouthBayAqueduct(SBA)atBethanyReservoir,1.2milesdownstreamfromBanks.FigureA.2isamapshowingthelocationsoftheSBAfacilities.TheSBAconsistsofabout11milesofopenaqueductfollowedbyabout34milesofpipelineandtunnelservingEastandSouthBaycommunitiesthroughtheZone7WaterAgencyoftheAlamedaCountyFloodControlandWaterConservationDistrict (Zone7WaterAgency),AlamedaCountyWaterDistrict (ACWD),andSantaClaraValleyWaterDistrict(SCVWD).WaterfromtheSBAcanbepumpedintoorreleasedfromLakeDelValleattheDelVallePumpingPlant.LakeDelVallehasanominalcapacityof77,110acre‐feet,with40,000acre‐feetforwatersupply.TheterminusoftheSBAistheSantaClaraTerminalReservoir(TerminalTank).
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Figure A. 1. The North Bay Aqueduct
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Figure A. 2. The South Bay Aqueduct
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FromBethanyReservoir,waterflowsintheCaliforniaAqueductabout59milestoO’NeillForebay,asshowninFigureA.3.TheforebayisthestartoftheSanLuisJoint‐UseFacilities,whichservebothSWPandfederalCentralValleyProject(CVP)customers.CVPwaterispumpedintoO’NeillForebayfromtheDelta‐MendotaCanal(DMC).TheDMCconveyswaterfromtheC.W.“Bill”JonesPumpingPlant(Jones)to,andbeyond,O’NeillForebay.TheO’NeillPump‐GenerationPlant(O’Neill Intake),locatedonthenortheastsideofO’NeillForebay,enableswatertoflowbetweentheforebayandtheDMC.SanLuisReservoirisconnectedtoO’NeillForebaythroughanintakechannellocatedonthesouthwest sideof the forebay.FigureA.4 is a locationmap that shows these features.Water inO’Neill Forebay can be pumped into San Luis Reservoir by the William R. Gianelli Pumping‐GeneratingPlant(Gianelli)orreleasedfromthereservoirtotheforebaytogeneratepower.SanLuisReservoir,withacapacityof2.03millionacre‐feet,isjointlyownedbytheSWPandCVP,with1.06millionacre‐feetbeingthestate’sshare.AnintakeonthewestsideofthereservoirprovidesdrinkingwatersuppliestoSCVWD.WaterentersSCVWDfacilitiesatPachecoPumpingPlant(Pacheco),fromwhichitispumpedbytunnelandpipelinetowatertreatmentandgroundwaterrechargefacilitiesintheSantaClaraValley.
Waterreleasedfromthereservoirco‐minglesinO’NeillForebaywithwaterdeliveredtotheforebaybytheCaliforniaAqueductandtheDMC,andexitstheforebayatO’NeillForebayOutlet,locatedonthesoutheastsideoftheforebay.O’NeillForebayOutletistheinceptionoftheSanLuisCanalreachoftheCaliforniaAqueduct,asshowninFigureA.5.TheSanLuisCanalextendsabout100milestoCheck21,nearKettlemanCity.TheSanLuisCanalreachoftheaqueductservesmostlyagriculturalCVP customers and conveys SWPwaters to points south. Unlike the remainder of the CaliforniaAqueduct,whichwasconstructedbythestate,theSanLuisCanalreachwasfederallyconstructedandwasdesignedtoallowdrainagefromadjacentlandtoentertheaqueduct.LocalstreamsthatruneastwardfromtheCoastalRangeMountainsbisecttheaqueductatvariouspoints.Duringstorms,waterfromsomeofthesestreamsenterstheaqueduct.Thisisgenerallynotthecasefortheotherreachesoftheaqueduct.
ThejunctionwiththeCoastalBranchoftheaqueductislocated185milesdownstreamofBanksandabout12milessouthofCheck21.TheCoastalBranchprovidesdrinkingwatersuppliestocentralCaliforniacoastalcommunitiesthroughtheCentralCoastWaterAuthority(CCWA)andtheSanLuisObispoCountyFloodControlandWaterConservationDistrict.FigureA.6isamapshowinglocationsofthesefacilities.TheCoastalBranchis115mileslong;thefirst15milesareopenaqueductandtheremainderisapipeline.
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Figure A. 3. California Aqueduct between Banks Pumping Plant and San Luis Reservoir
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Figure A. 4. O’Neill Forebay and San Luis Reservoir
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Figure A. 5. San Luis Canal Reach of the California Aqueduct
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Figure A. 6 The Coastal Branch of the California Aqueduct
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FromthejunctionwiththeCoastalBranch,watercontinuessouthwardintheCaliforniaAqueductasshown inFigureA.7, providingwater to both agricultural anddrinkingwater customers in theserviceareaofKernCountyWaterAgency(KCWA).TheKernRiverIntertieisdesignedtopermitKern River water to enter the aqueduct during periods of high flow. Due to increasingly scarceCaliforniawatersupplies,theSWPisusedtoconveybothsurfacewaterandgroundwateracquiredthrough transfers andexchanges among local agencies.Mostof thenon‐Projectwater enters theaqueductbetweenCheck21andCheck41.
EdmonstonPumpingPlantisatthenorthernfootoftheTehachapiMountains.ThisfacilityliftsSWPwaterabout2000feetbymulti‐stagepumpsthroughtunnelstoCheck41,locatedonthesouthsideoftheTehachapiMountains.Aboutamiledownstream,theCaliforniaAqueductdividesintotheWestandEastBranches.TheWestBranchflows14milestoPyramidLake,thenanother17milestotheoutlet of Castaic Lake, the drinking water supply intake of the Metropolitan Water District ofSouthernCalifornia(MWDSC)andCastaicLakeWaterAgency(CLWA).PyramidLakehasacapacityof 171,200 acre‐feet and Castaic Lake has a capacity of 323,700 acre‐feet.FigureA.8 is amapshowinglocationsofWestBranchfeatures.
FromthebifurcationoftheEastandWestBranches,waterflowsintheEastBranchtohighdesertcommunitiesintheAntelopeValleyservedbytheAntelopeValleyEastKernWaterAgency(AVEK)andthePalmdaleWaterDistrict(Palmdale).FigureA.9isamapshowingEastBranchfeatures.AsinthesouthernSanJoaquinValley,groundwaterfromthelocalareahasoccasionallybeenallowedintothe aqueduct to alleviate drought emergencies.On theEastBranchnearHesperia, surfacewaterdrainagefrompartofthatcityenterstheaqueductduringstormevents.TheinlettoSilverwoodLakeislocatedonthenorthsideofthereservoirnearCheck66.SilverwoodLakehasacapacityof74,970acre‐feet and serves as adrinkingwater supply for theCrestline‐LakeArrowheadWaterDistrict(CLAWA).WaterisdrawnfromthesouthsideofthereservoirandflowsthroughtheDevilCanyonPowerplanttothetwoDevilCanyonafterbays.DrinkingwatersuppliesaredeliveredtoMWDSCandSanBernardinoValleyMunicipalWaterDistrictfromthispoint,andwaterisalsotransportedviatheSantaAnaPipelinetoLakePerris,whichistheterminusoftheEastBranch.MWDSCroutinelytakesasmallamountofwaterfromLakePerris.
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Figure A. 7 California Aqueduct between Check 21 and Check 41
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Figure A. 8 The West Branch of the California Aqueduct
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Figure A. 9 The East Branch of the California Aqueduct
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A.2 NUTRIENT CONCENTRATIONS IN THE DELTA AND SWP
Nutrientconcentrationsshowconsiderableseasonalandspatialvariability.FiguresA.10toA.17showthevariabilityinnutrientconcentrationsatHood,Vernalis,BarkerSlough,andBanksaswellastheannualandinterannualvariability.FiguresA.18andA.19showdatawhichhasbeencollectedatanumberoflocationsalongtheCaliforniaAqueductfrom2004to2010.
Figure A. 10. Total N Concentrations at Hood
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Figure A. 11. Total P Concentrations at Hood
Figure A. 12 Total N Concentrations at Vernalis
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Figure A. 13. Total P Concentrations at Vernalis
Figure A. 14 Total N Concentrations at Barker Slough
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Figure A. 15. Total P Concentrations at Barker Slough
Figure A. 16Total N Concentrations at Banks
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Figure A. 17. Total P Concentrations at Banks
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0.20
0.25
0.30
To
tal
P (
mg
/L)
Dry Years
Wet Years
DeltaNutrients–DrinkingWaterIssues 75 June20,2017
Figure A. 18 Total N Concentrations in the SWP (2004-2010)
Figure A. 19 Total P Concentrations in the SWP (2004-2010)
Banks
Pacheco
O'Neill Forebay O
utlet
Check 21
Check 41
Castaic Outle
t
Devil Canyon
To
tal N
(m
g/L
)
0.0
0.5
1.0
1.5
2.0
2.5
Banks
Pacheco
O'Neill Forebay O
utlet
Check 21
Check 41
Castaic Outle
t
Devil Canyon
To
tal P
(m
g/L
)
0.00
0.05
0.10
0.15
0.20
DeltaNutrients–DrinkingWaterIssues 76 June20,2017
A.3 CYANOBACTERIA TAXA MAKEUP
Figure A.20 Proportion of cyanobacteria genera which are responsible for producing taste and odor compounds and toxin compounds.
DeltaNutrients–DrinkingWaterIssues 77 June20,2017
A.4 POTENTIAL ALGAL PRODUCTION OF SOURCE WATERS
Figure A.21 Algae production potential in Colorado River Water (CRW) versus State Water Project (SPW) based on a standard assay test using a common diatom test species Selenastrum using varying proportions of the CRW and SPW waters.