ReWild Mission Bay: Wetlands Restoration Feasibility Study ......Study area The ReWild Mission Bay...

ReWild Mission Bay:

Wetlands Restoration Feasibility Study Report

September 2018

EVEREST

PrefaceandExecutiveSummary-1

ReWildMissionBay:WetlandsRestorationFeasibilityStudyReportPrefaceSeptember24,2018“Wehavelearned,throughthepainfulmistakesofyesterday’signoranceandmyopia,thatwecannotviewthenaturalenvironmentassomethingapartfromthehumanrace…Shiftingthedirectionof

MissionBayParktoaccountforitslong-termecologicalhealthisachoiceforthefuture.”–CityofSanDiego’sMissionBayParkMasterPlan(August2,1994)

Fordecades,conservationistsatSanDiegoAudubonandthroughouttheenvironmentalcommunityhavededicatedthemselvestoprotectingMissionBay’sfragileremainingresourcesandtolaytheplansforitsfuturerestoration.AswemoveforwardindevelopingavisionforthefutureofMissionBayParkthatmeaningfullyintegratesprotectionofthenaturalenvironmentwiththerecreationalneedsofthecommunity,it’simportanttoremindourselvesofMissionBay’shistory-whatitwasandwhatithasbecome.Inthelate1800’s,MissionBaywasa4,000-acremosaicofwetlandhabitatssprawledacrossthemouthoftheSanDiegoRiver,forming“BahiaFalsa”or“FalseBay”.Formillennia,thiswetlandcomplexsupportedNativeAmericancommunitieswhoreliedontheBay’snaturalresources.TensofthousandsofmigratorywaterfowlandshorebirdsthrivedintheBay’seelgrass,mudflats,andsaltmarshastheytravelledalongthePacificFlyway,anorth-southhighwayofbirdmigration.Overmanycenturies,multitudesoffishemergedfromtheBay’swetland“fishnurseries”,contributingtoabundantfisheriesalongthesouthernCaliforniacoast.Overthepastseveraldecades,muchofthenaturalresourcesofMissionBayhavebeenaltered.“Derby’sDike”,builtin1853tore-routetheSanDiegoRiver,began150yearsoflarge-scalealterationoftheBaythatnearlyobliteratedthisglobaltreasureofbiodiversity.Duringthisperiod,wetlandswereviewedassomethingtodredge,fill,anddevelop.Ofthe4,000-acresofwetlandhabitatsthatonceexisted,merelyonepercent–40acres–remain.Inthepast,societydidnotunderstandthevalueofwetlandsystemsandtheecosystemservicestheyprovidetothehumancommunitiessurroundingthem.Today,weknowbetter.Weknowhowimportantwetlandsaretoourcommunities,ourcoast,andourwildlife.Weknowthattheyimprovewaterquality,stabilizeourcoastline,andprovidehabitatforwildlifelikeBrownPelicanandCaliforniaHalibut.

MISSION BAY


Toaddressthemistakesofthepast,wemustcreateanewvisionforMissionBayPark–onethatcorrectstheBay-wideimbalancethathasforsolongfavoredcommerceandactiverecreationattheexpenseoftheenvironment.ReWildMissionBayprovidesthisvision.ReWild’s375-pluspage“WetlandsRestorationFeasibilityStudyReport”outlineshowwecanrealizethisvision.InityouwillreadaboutnortheastMissionBay’secologicalhistory,existingparkland,leaseholdbusinesses,andhabitatuses,andwhatopportunitiesandconstraintslayaheadforrestoringthissmallbutimportantcornerofMissionBay.Youwilllearnaboutfouryearsofstakeholderoutreachandpublicengagementthatledtothedevelopmentofthreefinalconceptualplans,or“restorationalternatives”,thatshowfeasible,implementableplansforrestoration.Youwillcometoknowthedetailsofthesealternatives,includinghowmuchhabitateachalternativecreates,howresilienteachalternativeistosealevelrise,andtheopportunitiestheywouldprovideforexpandedrecreation,research,andeducationalopportunities.TheReWildMissionBayFeasibilityStudywasanintense,collaborativeeffortonthepartoftheWetlandsWorkingGroupsteeringcommittee,membersofReWildMissionBay’sScienceandTechnicalAdvisoryCommittee,andrestorationprofessionalsledbyEverestInternationalConsultants.Wethanktheseparticipantsandthehundredsofcommunitymemberswhoattendedourpublicworkshopsforengaginginthisplanningeffortandinspiringwhatiscontainedinthefinalrestorationalternatives.ThestudyanditsconclusionsprovidearoadmaptoguideustowardimplementationofwetlandsrestorationthatwillmakethepublicandtheCityofSanDiegoproud.Now,wecallonpoliticiansandcommunityleaderstomakethescientificallysound,forwardthinking,andsometimes-difficultdecisionsrequiredtorestorethesevaluablewetlands.ReWildMissionBay’sstudytoidentifyfeasiblewetlandrestorationalternativesrepresentsthefirsttimeinhalfacenturythatthepublichashadachancetohelpdeterminehowthesepubliclandsareused–landsthatbelongtoallofus.And,it’slikelyourlastchancetodosobeforeourcoastalcommunitiesexperiencesomeofthemostdamagingimpactsofachangingclimate.Let’sgiveagifttofuturegenerationsofSanDiegans–thegiftofenjoyingthebeautyofMissionBay’snaturalresourcesandbenefitingfromtheprotectionswetlandsprovideforourcoastlineandcommunities.Pleasejoinusinmakingthisvisionareality.Sincerely,RebeccaSchwartzLesbergReWildMissionBayProjectManagerSanDiegoAudubonChrisRedfernExecutiveDirectorSanDiegoAudubon


ReWildMissionBay:WetlandsRestorationFeasibilityStudyReportExecutiveSummarySeptember24,2018

ReWildMissionBayVision

ToenhanceandrestoreestuarinehabitatsinthenortheastcornerofMissionBayatthemouthofRoseCreek,contiguouswiththeKendall-FrostMarshReserve/NorthernWildlifePreserve,andexpand

opportunitiesforcompatiblecommunityaccesstothemarsh.ReWildMissionBayisacollaborativeeffortofSanDiegoAudubonandourpartnerstoprotectandrestorecrucialwetlandsinSanDiego’sMissionBay.AnimportantstepofthateffortisthisFeasibilityStudy,fundedbytheCaliforniaStateCoastalConservancyandUSFishandWildlifeCoastalProgram,whichaimedtodevelop,analyze,andevaluatearangeofwetlandsrestorationalternativesforthenortheasterncornerofMissionBayviaatransparent,publicinvolvementprocess.ThisStudyprovidesavisionforsite-specificrestorationalternativesthatarecapableofgarneringpublicsupport,agencyapproval,andimplementationfunding.GoalsofReWildMissionBay

• Goal1:Restore,enhance,and/orcreateestuarinehabitats(intertidalmudflat,saltmarsh,tidalchannels,&marsh/uplandecotone)toprovideecosystemfunctionsandservices,suchasfishandwildlifesupport,waterqualityimprovement,shorelinestabilization,carbonsequestration,andresistanceandresiliencetoclimatechangeandassociatedeffects.

• Goal2:Minimizedetrimentalanthropogenicimpacts(directandindirect)associatedwithsurroundingdevelopmenttotheexistingandrestoredestuarinehabitatsandassociatedwildlife.

• Goal3:Providenewand/orimproveopportunitiesforpublicaccess,education,research,and

recreationinwaysthatimproveunderstandingandstewardshipwhileprotectingtheexistingandrestoredestuarinehabitatsandassociatedwildlife.

MISSION BAY


Studyarea

TheReWildMissionBayFeasibilityStudyareaencompassesabout460acresinMissionBay’snortheastcorner,andincludesopenwater,developedparkland,lowerRoseCreek,andremnantwetlandhabitat.AreasoutlinedinredaredefinedasRestorationFocusAreas(RFAs)andareareasthatareeitherexistingwetlandsorareascalledoutintheCityofSanDiego’sMissionBayParkMasterPlanasopportunitiesforrestoration.Fromeasttowest,thethreeRFAsare:DeAnzaPointspecialstudyarea(83acres),Campland(52acres),andtheKendall-FrostMarsh/NorthernWildlifePreserve(66acres).Theformerly4,000-acrewetlandcomplexofMissionBaywasradicallyalteredbeginninginthe1940stocreaterecreationalopportunitiesforSanDiego,destroyingnearlyallofMissionBay’sestuarineresources.1Fortunately,aremnantoffunctionalhabitatremainsinMissionBay’snortheastcorner,attheKendall-FrostMarshReserveandadjacentNorthernWildlifePreserve,whichcomprisesapproximately10%ofthestudyarea.Theotherapproximately90%ofthestudyareaismadeupofdevelopedparkland,largelywithinMissionBayPark,andownedbytheCityofSanDiego.

1ForamorecompletedescriptionoftheBay’shistoricalecology,seetheSanFranciscoEstuaryInstitute’s“MissionBayHistoricalEcologyReconnaissanceStudy”foundasanappendixtothefullreport.


Afive-stepprocessThefollowingfive-stepprocesswasutilizedtoaddressthevisionandgoalsoftheproject.

1. Acomprehensivedescriptionofexistingconditions2. Explorationofkeyopportunitiesandconstraintsinrealizingourvision3. Publicengagementinexploringpotentialrestorationfeatures4. Refinementofpublicly-vettedrestorationelementsintothreedraftalternatives5. Detailedanalysisandevaluationofthreefinalalternativesinmeetingprojectgoals

Theresultsfromthesefivestepsaresummarizedbelow.1.EXISTINGCONDITIONS:ExploringpossibilitiesforwetlandsrestorationinnortheastMissionBayToinformrestorationopportunities,anexaminationofthestudyareawascompletedtounderstandexistingconditions.Thisexaminationincludedinformationonphysicalattributesofthesitearea(e.g.,geomorphology,bathymetry,topography);processessuchashydrology,sedimentation,watercirculation,andwindandwaveaction;biologicalresources,ecologicalfunction,andwaterquality;andlanduse,publicaccess,andrecreationinformation.AnelevationalmosaicofwetlandhabitatswithinaconstrainedlandscapeTheKendall-FrostMarshReserveisownedandoperatedbytheUCNaturalReserveSystem,andtogetherwiththeCityofSanDiego’sNorthernWildlifePreserve,includes88acresofsaltmarsh,mudflat,tidalchannels,andsaltpanne.TheMarsh/Preserveisfringedbymostlydisturbeduplandcoastalsagehabitat,withsomeactiverestorationunderwayledbytheUCNaturalReserveSystemandpartners.Althoughsmallinsize,theMarsh/Preservehabitatsupportsabundantwildlife,includingfish,benthicinvertebrates,andmorethan160speciesofbirds.Threestateand/orfederallylistedspeciesusethehabitatinthestudysite,includingtheCalifornialeasttern,light-footedRidgway’srail,andBelding’ssavannahsparrow.TheKendall-FrostMarshReserveandNorthernWildlifePreserveareconsideredtobelynchpinsforwetlandsrestorationopportunitiesinMissionBay.Thatisbecauserestorationoutcomesarenearlyalwaysmoresuccessfulwhenwetlandsarerestoredadjacenttoexistingfunctionalwetlandhabitatratherthanrestoringwetlandswherenoneremainorexistedpreviously.Also,theproximityofRoseCreektotheseremnantwetlandsprovidesanopportunitytoreestablishthehistoricalconnectionbetweenthecreekandthemarsh,providingmuch-neededfreshwaterandsedimentinputsnecessaryforhealthymarshfunction.ThestudyareaisconstrainedonthreesidesbydensesuburbandevelopmentanddevelopedparklandwiththefourthsideopenwateroftheBay.Landuseswithinandadjacenttothestudyareaincludeapublichighschool,residentialhousing,roadways,parkinglots,utilities,developedparkland,andbusinessesoperatingonCityparklandvialeaseagreements(e.g.,RVcampingatCamplandontheBay,andabandonedmobilehomesonDeAnzaPoint),whichareservedbyinfrastructurethatprovideutilities,water,lighting,stormdrain,andsewerservices.


WateronthemoveWetlandsareecosystemsdefinedbyperiodicinundationwithwater.InMissionBay,watersfromthePacificOceanflowinandoutofthemouthofthebay,generatingacirculationpatternthatinfluenceswaterlevelsandwaterqualityinourstudyareaandthroughoutthebay.RoseCreek,whichbisectstheReWildstudyarea,isthelargestsinglesourceoffreshwatertoMissionBay,followedbyTecoloteCreekandsomeyear-roundinputsfromurbanrunoff.InputsfromrainoccurmostlyinthewinterandspringwhentheSanDiegoregionreceivesmostofitsprecipitation.Duringtheserainevents,stormdrainsalsocontributetowaterflowsinthearea(includingrunofffromimpervioussurfaceswithinthestudyarealikeattheCamplandontheBayRVPark,DeAnzaMobileHomePark,andparkinglots).WaterqualityisdynamicintheBayandcanchangedramaticallyaspollutantsareflushedintotheBayfromthewatershedsabove.Anumberofwaterbodies/shorelineswithinourstudyareaarelistedasimpairedunderSection303(d)oftheCleanWaterAct,includingthestreamcourseofRoseCreek,themouthofRoseCreek,andboththeCamplandandDeAnzaCoveshorelines.DeAnzaCove,locatedfarfromthemouthoftheBay,suffersfromsomeoftheworstwaterqualityinthePark.Giventheimpervioussurfacescomprisingthewatershedacreage,largeprecipitationeventscancreatedramaticincreasesofflowdownRoseCreek.Suchflowstransportlargequantitiesofsedimentthataredepositedatthemouthofthecreekandovertimeimpedenavigation.Theycanalsocauseandexacerbatewaterqualityissues.2.OPPORTUNITIESANDCONSTRAINTS:Buildingamoreresilientmarsh,withBay-widebenefitsRestorationinthisparticularpartoftheBaycomeswithasuiteofopportunitiesthatincreasethelikelihoodofsuccessfortheproject,aswellasconstraintsthatpresentpotentialchallengestoovercome.Theseinclude:Opportunities:

• Reductionofhumanimpacts:Restoringcoastalsaltmarshadjacenttoexisting,functionalhabitatcreatesalargercontinuoushabitatarea,increasingecologicalfunctionandreducingtheproportionofthehabitatsubjecttoedgeeffects,includingtheeffectsofurbanpredatorsonsensitivewildlife,spreadofinvasivespecies,andotherhuman-relatedimpacts.

• Nutrientsforthemarsh:ReWildrestorationalternativesalllowertheelevationsoflandformsadjacenttothebanksofRoseCreek.Thisrestorationofamorenaturaldelta-likelandformwouldallowwaterfromRoseCreektofanoutuponreachingtheBayversusexitingtheconstrainedcreekchannelathighspeed.Asthewaterfansout,itwouldcarryfreshwaterandsedimentsintothemarsh,providingessentialnutrientsandsedimentnecessaryforhealthymarshfunction.

• Waterqualityimprovements:RedirectionandredistributionofwaterflowsfromRoseCreekintomarshhabitatwouldalsoreducepollutantsbeforetheyreachMissionBay,improvingwaterqualitywithintheentireBay.


• Timing:Formorethantwentyyears,theMissionBayParkMasterPlanhascalledforhabitatrestorationwithinthecurrentfootprintoftheCamplandleaseholdandcallsforwetlandscreationandwaterqualityimprovementsfortheDeAnzaSpecialStudyArea.WiththeresolutionofalawsuitbetweentheCityofSanDiegoandDeAnzaMobileHomeParkresidents,andwiththeleaseholdforCamplandexpiringin2020,significantopportunitiesnowexistforwetlandsrestorationtomoveforward.

• Compatibleadjacentuses:Landusesadjacenttorestorationfocusareasincludeopenparklandandagolfcoursewithfewbuildingsandstructures,providingthepossibilityforfuturerestoration,buffersbetweenrestoredhabitatandheavyhumanuseareas,andpotentialareasforwetlandupslopemigrationinthefuture.

• Likelihoodofcompatiblesoils:Historically,theareasofCamplandandDeAnzaPointwerewetlandbeforebeingfilledanddeveloped.Therefore,itisgenerallythoughtthatthewetlandsoilsneededforrestorationlikelystillpersistunderneaththefill.Ifthisistrue,whenthefillisremoved,theunderlyingsoilswouldlikelysupportwetlandplantswithoutsignificantsoilaugmentation.Inaddition,itislikelythatthesoilsplacedasfillweredredgedfromtheBaysothosesoilsmayalsosupportwetlandplantswithoutsignificantsoilaugmentationaslongastheplacedfillsoilshavenotbecomecontaminatedovertime.

• Nearbyplantsandanimals:Sincetheareasforproposedrestorationareadjacenttoexistingmarshhabitat,itisexpectedthatmarshplantcommunitieswouldreadilyrecolonizetherestorationareawithoutsignificantactiverestoration.Expandedmarshhabitatwouldalsoprovidemorerefugeareasforwildlife,andallowpotentialexpansionofpopulationsofendangeredandthreatenedspecies.

Constraints:

• Soildisposal:Materialexcavatedtoreduceelevations(i.e.,bringtheheightoftheDeAnzaandCamplandRFAsdowntosealevel)wouldneedtobetestedforcontaminants.Ifthesoilisclean/non-hazardous,therearelikelywaystoreusethematerial.Sandysoilcouldbeusedtoreplenishnearbybeachareas,andwetlandsoilscouldbeusedtoshallowexistingopenwatertoexpandthefootprintoflowmarshhabitatandmid-marshhabitatintheBay.

• PotentialimpactstoCityleaserevenue:TherestorationofwetlandsinthestudyareacouldrequiretheremovalormodificationofsomerecreationallandusesatCamplandandDeAnzaPoint,whichwouldimpacttheCity’sleaserevenueandrepresentsapotentialconstrainttorestoration.However,thisuseconversionwouldreducewaterqualityimpactstotheBaycomparedtoexistingconditionsorredevelopmentwithintheRFAs.

AchancetoexploreandlearnaboutwetlandsToday,theremnantKendall-FrostMarshReserveandNorthernWildlifePreservearesosmallandsubjecttoedgeeffectsthatpublicaccessisextremelylimited.Anexpandedmarshfootprintwouldallowforexpandedopportunitiesforthepublictoexploreandlearnaboutwetlandecosystems.AllReWildrestorationalternativesincludepublicaccess,includingoverlooksandinterpretivetrailsystemsthatwouldbeconnectedtoexistingparkland,walkway,andbikewayinfrastructure.Scientificandeducationalinstitutionshaveusedhabitatareasinthestudyareaformanyyearsandthisuseisexpectedtoexpandwithrestorationefforts.Teachingandresearchactivitiescurrentlyunderway


includerelationshipswithMissionBayHighSchoolanditsassociatedmiddleandelementaryschools.Long-termresearchandteachingatthepost-secondarylevelisfacilitatedbytheUniversityofCaliforniaNaturalReserveSystem,andincludesrelationshipswiththeUniversityofCaliforniaSanDiego,SanDiegoStateUniversity,PointLomaNazareneUniversity,andtheUniversityofSanDiego.3.PUBLICENGAGEMENT:BuildingdurableconsensusforrestorationInordertogivethelocalandregionalcommunityachancetoparticipateinandhelpinformtherestorationdesign,aswellastobuildsupportandconsensusforrestorationinourstudyarea,theReWildMissionBayFeasibilityStudybeganwiththedevelopmentofastakeholderoutreachandpublicinvolvementplan.EngagingkeystakeholdersandthepublicAScienceandTechnicalAdvisoryCommittee(STAC)wasformedtoprovideinformationandadviceonthestudy’sworkproducts,toensurethatallmaterialswereinformedbythebestavailablescienceandbyknowledgeofexistinginfrastructureandplanningefforts.STACmembersincludedstafffromanumberofCitydepartments(e.g.,Planning,TransportationandStormWater,ParksandRecreation),wetlandscientists,andwildlifeagencystaffaswellasregulatoryandresourceagencystaff.KeystakeholderswereengagedattheoutsetofthiseffortbyformingaCommunityRepresentativesGroup,whichincludedlocalcommunityleaders,representativesfromgroupsusingcurrentparkamenities,leaseholderbusinesses,education-relatedgroupsconductingresearch,andotherinterestedparties.Communitymembersalsoparticipatedinfourpublicworkshopstimedtocoincidewithkeyprojectmilestones.FourworkshopswereheldatMissionBayHighSchooloveratwelve-monthperiodfromthespringof2016tothespringof2017.Publicengagementwasrobust,withanaverageofmorethan80communitymembersattendingeachworkshop.Peoplewereencouragedtoprovidewrittenfeedbackatthemeetingsoronlinethroughacomprehensivepublicwebsite.DevelopmentofrestorationscreeningalternativesAninitialsetofrestorationalternativesweredevelopedtoscreenrestorationideas,concepts,measures,andfeatures.Inkeepingwithaninclusive,transparentplanningprocess,developmentofrestorationalternativesbeganwitha“bottom-up”gatheringofrestorationideasandconceptsfromcommunitymembersinthefirsttwopublicworkshopsandbyfeedbacksubmittedviatheReWildMissionBaywebsite.RestorationideasandconceptswerealsosolicitedfromtheWetlandsWorkingGroup,ScienceandTechnicalAdvisoryCommittee,andtheconsultantteam.Eightinitialscreeningalternativeswerecreatedviathismultifacetedinput,andthreeadditionalalternativesweredevelopedtoaddressconsistencywiththeCaliforniaCoastalCommission2015SeaLevelRisePolicyGuidance.Mapsofthesealternativescanbefoundonpages104-109ofthefullreport.


4.REFINEMENTOFALTERNATIVES:NarrowingthefieldNarrowingdownrestorationalternativestothreeoptionswasnecessarybeforeproceedingtoamorein-depthstudyofhowthevariousfeaturesandoptionswouldfunctionandmeetprojectgoals.Ascreeningprocesswasusedtoevaluateeachoftheelevenscreeningalternatives.FeaturesthatwerenotscreenedoutthenbecamethebuildingblocksfordraftAlternativesA,B,andC.Broadly,thescreeningcriteriafocusedon:

• Technicalfeasibility• AlignmentwithMissionBayParkMasterPlanwaterqualityobjectivesandwetlandrestoration

areagoalsrevisedtoaccountforprojectedsea-levelrise• Analysisofthefeature’sandmeasure’scontributionstomeetingrestorationgoals• Considerationofexpectednon-habitatlanduseneedsinthestudyarea,includingneeds

outlinedintheCity’sDeAnzaRevitalizationproject(aprojectinitiatedbytheCityofSanDiegoin2015withinthefootprintoftheReWildstudyarea)

ThedraftAlternativesA,B,andCareshowninFigures5.13,5.14,and5.15ofthefullreport(foundonpages111-113).Furtherrefinementbasedonsea-levelriseandCitylandusepreferencesTwosignificantfeasibilityconstraintswereidentifiedatthispointinthefeasibilityprocess:sea-levelriseandinputfromtheCityofSanDiego’sPlanningDepartmentregardinglandandshorelineuseneedsinthestudyarea.Computermodelingconductedbytheconsultantteamindicatedthatprojectedsealevelrisewouldnotonlydrowntheexistingmarshareas,butwouldalsodramaticallyimpactrestoredhabitatareasovertime.HabitatconversionandresultinglossofecosystemfunctionwouldmeanthatthevisionofrestoringawetlandssystemresilienttosealevelrisecouldnotbeachievedusingtheexistingdraftAlternativesA,B,andC.TheMissionBayParkMasterPlancalledforanadditionofatleast80acresofwetlandsinnortheastMissionBaythatwouldcomplementtheexisting40acresattheKendallFrostReserve/NorthernWildlifePreserve.Assuch,theMissionBayMasterPlanenvisioned120acresofwetlandsinnortheastMissionBay.However,toretain120acresofwetlandsthatwouldbeabletopersistinthefaceofsealevelrisethroughtheyear2100,modelsindicatedthatmorethan200acresofwetlandandassociatedhabitatwouldneedtobeconservedandrestoredtoday.Inordertoretainmorehabitatintothefuture,twoofthethreefinalalternativesweremodifiedtoincludemorehabitatareatothesouth/southwestofCampland.In2017,theCityofSanDiegorequestedthatReWildincludeanalternativetoaccommodatefortyacresofguesthousingwithintheDeAnzaSpecialStudyArea,whichlieswithinthefootprintofourstudyarea.Oneofthedraftalternativeswasmodifiedtoaddressthispotentialconstraint.Acloserlookatfinalalternatives“Wild”,“Wilder”,and“Wildest”AllthreefinalrestorationalternativesforReWildprovideadistributionofhabitatsthatincludesubtidal,mudflat,lowsaltmarsh,mid-highsaltmarsh,andtransitional/uplandhabitattypes.Table6.1


onpage117ofthefullreportshowsthedistributionsofeachhabitattypeintheyears2020,2050,and2100withanticipatedsea-levelriseofzero,2.0,and5.5feet,respectively.Duetodifferenthabitatconfigurations,theareaofdifferenthabitattypesprovidedbyeachalternativechangeovertimeassealevelsrise.This,inturn,affectshoweachalternativeperformsinsupportingparticularplantandanimalspeciesthatdependondifferenthabitattypes.Acomprehensivediscussionofthesetrade-offscanbefoundinchaptersixofthefullreportandabroadoverviewispresentedbelow.

ReWildMissionBayProjectedHabitatDistributions

Habitat/RecreationalUseYear2020(NoSLR)

Year2050(2.0ftofSLR)Area(Acres)

Year2100(5.5ftofSLR)

“Wild”AlternativePassiveandactiverecreation

withappropriatebuffer 97 97 97

Habitattotal* 214 184 84SaltMarshtoUplandTotal 172 94 45

“Wilder”AlternativePassiveandactiverecreation



“Wildest”AlternativePassiveandactiverecreation



*Habitattotal=sumofmudflat,saltmarsh,transitional,anduplandhabitats


The“Wild”AlternativeThe“Wild”alternativeexploresopportunitiestorestorewetlandsexclusivelywithintheRestorationFocusAreasofCamplandandDeAnza,anddoesnotproposeshallowingadjacentopenwateroranymajormodificationstotheoutlinesofexistinglandforms.Thisminimizesissuesrelatedtothepermittingofplacingfillinopenwater.However,thisalternativeachievedthelowestamountofrestoredhabitatandtherequiredloweringofelevationsatCamplandandDeAnzawouldnecessitateexportingalargevolumeofsoiloff-site,resultinginimpactstotraffic,airquality,andgreenhousegasemissions.

Followingrestoration,“Wild”wouldprovide172acresofwetlandhabitat(saltmarshtouplandgradient);by2100(or5.5feetofsea-levelrise),thehabitatextentshrinksto45acres.


The“Wilder”AlternativeThe“Wilder”alternativewascreatedtoreflecttheminimumdistributionof‘Habitat-OrientedRecreation/Preservation’asshownintheMissionBayMasterPlanandinresponsetotheCity’srequesttoaccommodate40acresofguesthousingonDeAnzaPoint.“Wilder”usessoilexcavatedfromtheCamplandRFAtoshallowapproximately38acresofopenwaterandindoingsocreatemudflat,lowsaltmarsh,andmid-highsaltmarsh.Thisoptionprovidesgreaterresiliencytosea-levelriseascomparedtothe“Wild”alternativeandreducestheneedtoexportsoiloffsite,reducingtraffic,airquality,andgreenhousegasimpacts.

Followingrestoration,“Wilder”wouldprovide164acresofwetlandhabitat(saltmarshtouplandgradient);by2100(or5.5feetofsea-levelrise),thehabitatextentshrinksto40acres.


The“Wildest”Alternative

The“Wildest”alternativeexpressesavisionwherebywaterquality,sea-levelriseadaptation,andtheabilityforwetlandhabitatstopersistovertimewereoptimized.The“Wildest”alternativeproposesusingsoilfromboththeCamplandRFAandareasontheDeAnzaPointRFAtoconvert94acresofopenwatertorestoremudflat,lowsaltmarsh,andmid-highsaltmarshonbothsidesofRoseCreek.Thisalternativeprovidesthegreatestresiliencytosea-levelriseofalloptions.The“Wildest”alternativealsorepresentsabalancedcutandfilloption,virtuallyeliminatingtheneedtoexportsoiloffsiteandgreatlyreducingtherelatedimpactstotraffic,airquality,andgreenhousegasemissions.Followingrestoration,the“Wildest”alternativewouldprovide227acresofwetlandhabitat(saltmarshtouplandgradient);by2100(or5.5feetofsea-levelrise),thehabitatextentshrinksto75acresandindoingsomostcloselyretains120acresofwetlands(calledforintheMissionBayParkMasterPlan)overan80-yearprojectlifespan.


5.DETAILEDANALYSIS:Evaluatinghow“Wild”,“Wilder”,and“Wildest”performinachievingtheReWildvisionThisprojectconductedtidalandfluvialhydraulicmodeling,sea-levelrisemodeling,habitatareacalculations,estimatesofquantitiesofearthworkrequired,analysisofpublicaccess,andconstructioncostestimates.Theseanalyseswereusedtoevaluatehowwelleachofthealternativesmettheproject’sgoals.TidalandfloodingeffectsofrestorationalternativesReWildMissionBay’sfinalwetlandrestorationalternativesincludesignificantchangestolandformswithintheBayaswellastheshallowingofexistingopenwaterhabitatareasin“Wilder”and“Wildest.”Theseelevationalchangesmayaffecttidalaction(movementofwateronthedailytides)andresultingwaterlevelsinrestoredhabitatandnon-habitatareas.LandformchangesnexttothemouthofRoseCreekarealsoexpectedtochangethespeedandcourseoffreshwaterflowingintotheBay,knownasfluvialinputs.Giventhesignificanceofsuchpotentialchange,theReWildconsultantteamdevelopedahydrodynamicmodeltocharacterizetidalandfluvialflooddynamicswithinthestudyarea.Thetwo-dimensionalTUFLOWhydrodynamicmodelwasdevelopedtoanalyzeexistingtidalandfloodconditionsinthestudyareaasitexiststoday.Then,thesamemodelwasusedforeachofthethreefinalrestorationalternativestodeterminehoweachwouldaffecttidalandfloodconditions.Acompletediscussionofthemodelingmethodologyandresultscanbefoundonpages148-187ofthefullreport.Majorfindingsinclude:

• Overall,tidalandfloodvelocitieswouldbegenerallylowerunderproposedrestorationalternativescomparedtoexistingconditions

• RestorationalternativesmoderatelyreducetidalvelocitiesatthemouthofRoseCreek• Tidalvelocitieswithinproposedmarshchannelswouldbelow• 100-yearfloodlevelsinthethreefinalrestorationalternativesaresimilarastowhatisseen

todayunderexistingconditions• RestorationalternativesgenerallyreducehowfarfloodvelocitiesextendintotheBayunder

100-yearfloodconditions• Differencesbetweenhowthethreefinalrestorationalternativeswouldaffecttidalandflood

conditionsweremodestSea-levelriseeffectsofrestorationalternativesTheCaliforniaCoastalCommission’s2015SeaLevelRisePolicyGuidanceprojectsamaximummeansea-levelriseof5.5feetbytheyear2100.Toanalyzetheeffectsof5.5feetofsea-levelriseonthefinalrestorationalternatives,theReWildconsultantteamsettidewaterlevelsto5.5feetabovecurrentconditionsandthenre-rantheTUFLOWhydrodynamicmodeldescribedabove.Sea-levelriseeffectsonhabitatdistributionsareillustratedinfigures6.4–6.9onpages121-126ofthefullreport.


Undera5.5feetmeansea-levelrisescenario:

• Tidalvelocitiesunderthefinalrestorationalternativeswouldbelessthanthetidalvelocitiesunderexistingconditions(i.e.,withouthabitatrestoration)

• 100-yearfloodlevelsaresimilarunderexistingconditions(i.e.,unrestorednortheastportionofMissionBayinYear2100withsea-levelrise)andthefinalrestorationalternatives

• 100-yearhighfloodvelocitiesunderthefinalrestorationalternativesdonotextendasfarintoMissionBayandareshiftedtothewestascomparedtoexistingconditions

• 100-yearfloodextentwouldlargelyinundatehabitatareasofallthreefinalrestorationalternatives

How“Wild”,“Wilder”,and“Wildest”optionsstackupinmeetingrestorationgoalsGoal1:Restore,enhanceand/orcreateestuarinehabitats(intertidalmudflat,saltmarsh,tidalchannels,transitional,&upland)toprovideecosystemfunctionsandservices,suchasfishandwildlifesupport,waterqualityimprovement,shorelinestabilization,carbonsequestration,andresistanceandresiliencetoclimatechangeandassociatedeffects.TheprimarymetricforachievingGoal1istheoverallsizeoftherestorationfootprint.Therefore,“Wildest”mosteffectivelymeetsthisgoal.Inprovidingthelargestareaofhabitat,“Wildest”providesthebestoverallfishandwildlifesupport.Moresaltmarshhabitatprovidesgreaterfiltrationofpollutantstoimprovewaterquality.Alargerwetlandsfootprintleadstogreatercarbonsequestration.Andbyprovidingmoretransitionalhabitat,“Wildest”providessuperioropportunitiesforshorelinestabilizationandforhabitattomigrateupslopeassealevelsrise.(Itisimportanttonote,however,thatsea-levelrisewillfragmenthabitatareasconsiderablyinallthreefinalrestorationalternatives.)Perhapsmostconsequentially,thesea-levelriseanalysisindicatesthatthe“Wildest”alternativeistheonlyalternativelikelytoretainahabitatdistributionwith5.5feetofsea-levelrisethatcanmeaningfullyprovidetheecosystemfunctionsandservicesoutlinedinthisgoal.Goal2:Minimizedetrimentalanthropogenicimpacts(directandindirect)associatedwithsurroundingdevelopmenttotheexistingandrestoredestuarinehabitatsandassociatedwildlife.Manydirectandindirecthuman-causedthreatstorestoredhabitatarebeyondtheplanningscopeofthisproject,includingchangestohowsurfacewaterrun-offismanagedonadjacentlanduses,limitingrecreationalactivitiesthatmayharmhabitatsordisturbwildlife(e.g.,jetskisandboats),andproposingchangestonearbydredgingactivities.Thesizeofuplandandtransitionhabitatzonesincludedineachrestorationalternativeprovidesausefulmetricforindicatinghowwelleachoptionaddressesthisgoal.Asthe“Wildest”alternativeprovidesthelargestacreageofuplandandtransitionhabitat,itperformsbestinachievingtheprotectionofsensitivehabitatsandwildlifefromhumandisturbance.SeeTable6.1inthefullreportforacreagedetails.


Goal3:Providenewand/orimproveopportunitiesforpublicaccess,education,researchandrecreationinwaysthatimproveunderstandingandstewardshipwhileprotectingtheexistingandrestoredestuarinehabitatsandassociatedwildlife.Eachofthethreefinalrestorationalternativesincludedesignfeaturesthataddressthisgoal,includingobservingminimumwetlandsetbacks,usingexistingtrailalignmentsforhigh-useareasandseparatingpedestrianandbicycleuserswhenpossible,andworkingtobalancecompetinggoalsofpublicaccessandprotectionofwildlifeandhabitats.Trailconfigurations,overlooklocations,visitorcenters,andotherinterpretiveinfrastructurearealluniquetoeachofthethreefinalrestorationalternativesandarenotreadilycomparableforevaluativepurposesrelatedtothisgoal.Detailscanbefoundonpages212-218ofthefullreport.Afewmajortakeawaysinclude:

• The“Wilder”alternativeprovidesthefewestopportunitiesfornature-basedrecreationofallthealternatives.However,ithasthegreatestamountofactiverecreationaldevelopmentadjacenttohabitateastofRoseCreek.Therefore,publicaccessonthewestsideofRoseCreekwascurtailedtominimizeedgeeffectsandprotecthabitatandecosystemfunction.

• Thoughthe“Wild”alternativeprovidesthegreatestlengthoftrailsthroughhabitat,“Wildest”providesthegreatest“timeofexposure”tonaturebecauseitincludesaccesstoalong,contiguousedgeofhabitatviaaperimetermulti-usetrail.

• Duetothenorth-southextentofthehabitatproposedinthe“Wildest”alternative,thisalternativeprovidesopportunitiesforinterpretivetrailstoextenddeeperintohabitatzoneswhilemaintainingdesiredsetbacksfromwetlands.

• Duetosea-levelriseandthemigrationofwetlandshabitatsupslope,interiortrailsofallthreefinalrestorationalternativeswouldlosedesiredwetlandssetbacksandwouldneedtoberelocatedovertime.

Comparingimplementationcostsof“Wild”,“Wilder”,and“Wildest”TheReWildconsultantteamcomparedestimatedimplementationcostsforeachofthethreefinalrestorationalternatives.Indevelopingcostestimates,itwasassumedthatcostsforenvironmentalreview,permitting,andfinaldesign/engineeringwerethesameforeachofthealternatives($4,500,000).Therefore,thecostdifferencesbetweenalternativesweresolelyconstruction-related.Costswereestimatedassumingthataportionofexcavatedsoilswouldcontainmoderatelevelsofcontamination.Differencesinconstruction-relatedcostslargelydependonhowmuchgradingworkisneededtocreatetheelevationstosupportwetlandandassociatedhabitattypes,theamountofsoilneededtoberemovedoff-site(ifany),andthemethodofdisposal(e.g.,bytruckorbarge).Totalcosttoimplementthealternativesischeapestfor“Wilder,”followedby“Wildest”andthen“Wild”whilecostperunitacrerestoredwascheapestandsimilarbetween“Wildest”and“Wilder”andmoreexpensivefor“Wild.”


SummaryofImplementationCostEstimates(in2017MillionofDollars)

Item“Wild” “Wilder” “Wildest”

LA-5Disposal

UplandDisposal

LA-5Disposal

UplandDisposal

On-SiteDisposal

TotalCost($Million) 97.8 91.4 46.4 46.2 62.6RestorationUnitCost

($million/Acreofhabitat***)0.41 0.38 0.16 0.15 0.16

RestorationUnitCost($million/Acreofwetlandhabitat*)

0.54 0.50 0.19 0.19 0.22

RestorationUnitCost($million/Acreofwetlandrestored**)

1.07 0.99 0.34 0.33 0.35

*mudflat,low,midandhighsaltmarshes,includesexistingwetlandinKFMR/NWPbutexcludespublicaccessfeatures**mudflat,low,midandhighsaltmarshes,excludesexistingwetlandinKFMR/NWPandpublicaccessfeatures

***mudflat,low,midandhighsaltmarshes,transitional,uplands,includesexistinghabitatsatKFMR/NWPbutexcludespublicaccessfeatures

Restorationalternativecostswerealsoevaluatedona“restorationunitcostperacre”basis,providingacostcomparisonrelativetothesizeofrestorationareaachieved.Restorationunitcostperacreisdefinedasthetotalimplementationcostdividedbythetotalacreageofwetlandhabitatcreated(mudflat,low,andmid-highsaltmarsh).Theevaluationfound“Wild”tobemorethandoubletherestorationunitcostversus“Wilder”and“Wildest”,with“Wilder”and“Wildest”havingsimilarrestorationunitcosts.DetailscanbefoundinTable8.6onpage196ofthefullreport.CONCLUSIONSANDNEXTSTEPS:RealizingthevisionforresilientwetlandsinnortheastMissionBayWecandothisRegardingthefundamentalquestionofwhetheritisfeasibletorestorewetlandsandassociatedhabitatsinthenortheastcornerofMissionBay,thisstudyprovidesanunequivocalanswer:yes.ThecloseproximityofthestudysitetoexistingremnantcoastalwetlandsatKendall-FrostMarshReserveandtheNorthernWildlifePreserveprovidesconfidencethatrestoringadjacentareaswouldbesuccessful.Additionally,opportunitiestoreconnectRoseCreektoexistingandnewlyrestoredwetlandswouldprovidemuchneededfreshwaterandsedimenttonourishthehabitatsandmaintainmarshelevations.Finally,hydrodynamicmodelingresultsindicatethatrestorationalternativesdonotincreasefloodingriskinthearea,andinfactslowfloodvelocitiescomingdownRoseCreek.TheReWildMissionBayWetlandsRestorationFeasibilityStudywasinitiatedwithavisiontodevelop,analyze,andevaluatearangeofwetlandsrestorationalternativesforthenortheasterncornerofMissionBayviaatransparent,publicinvolvementprocess.Resultsofthisstudyshowthatthe“Wildest”alternativebestachievestheStudygoalsofenhancingandrestoringwetlandshabitatresilienttoclimatechangeandmaximizinguplandandtransitionhabitattominimizehumanimpacts.“Wildest”alsoprovidesthegreatestopportunitiesforpublicaccess,educationalresearch,andrecreationinconfigurationssimilarinscopeandopportunityastheotherReWildalternatives.


NextstepsTheReWildMissionBayteamoffersthefollowingassuggestednextstepsineffortstorealizethevisiontoenhanceandrestoreestuarinehabitatsinthenortheastcornerofMissionBay:

• IntegratetheReWildAlternativesandassociatedanalysisintotheCity’sDeAnzaRevitalizationPlanforcompleteanalysis.

• Inconsiderationoftheallowanceof40acresofguesthousingonDeAnzaPointinthe“Wilder”alternative,considerincreasingwetlandhabitatareasinothersectionsofthestudyarea,includingshallowingopenwaterattheheelofDeAnzaPoint,intheopenwatersouth/southwestofCampland,andfartherintoDeAnzaCove.

• LocatelowestintensityrecreationusesclosesttotherestoredwetlandsanddesigntheseareaswithfeaturesthatuseBestManagementPracticestominimizepollutantimpactsandbufferrestoredhabitatfromlight,noise,andotherhumanimpacts.

• EvaluateanyfinalplanforitsabilitytoaddresslocalizedandBay-widewaterqualityimpactsandimplementanydesignelementsidentifiedthatcanmitigatetheseimpacts.

• Ensurethatsea-levelriseimpactsarefullyandcompletelyanalyzedintheenvironmentalreviewforthcomingfromtheCityofSanDiego’sDeAnzaRevitalizationPlan.

• EnsurethatalldevelopmentandwetlandsrestorationplanninginnortheastMissionBayisplanned,evaluated,andimplementedasapartofonecohesiveprocess.

• PlantocreatemorewetlandsinnortheastMissionBaythanwhatisproposedbythisprojecttofulfillMissionBayMasterPlan’svisionof120acresofwetlandsinnortheastMissionBay(i.e.,creationof80newacresincombinationwiththeexisting40acres)assealevelsrise.

SanDiegoAudubonlooksforwardtocontinuingourcollaborationwiththepublic,keystakeholders,andtheCityofSanDiegotorealizethevisionofdevelopingresilientwetlandsinnortheasternMissionBay,includingfurtherrefinementofrestorationalternatives,phasingandmitigationplanning,andultimatelyenvironmentalreviewandconstruction.Tolearnmore,visitrewildmissionbay.orgWeinviteyoutolearnmoreabouttheReWildMissionBayprojectandthisFeasibilityStudybyvisitingourwebsiteatrewildmissionbay.org,whereyouwillfindallprojectmaterials,includingnewsonprojectmilestones,presscoverage,materialsandreportsfromourpublicworkshops,blogpostsannouncingprojectmilestones,andmore.Youcanalsosignuptoreceiveperiodicupdatesviaemailbyvisitingrewildmissionbay.org/get-involved.ProjectTeamSanDiegoAudubonSocietyledtheReWildMissionBayFeasibilityStudy,withEverestInternationalConsultantsservingastheleadforthetechnicalconsultantteam.TheEverestteamincludedNordbyBiologicalConsulting,NewLandWestCompany,andAECOM.SanDiegoAudubonassembledasteeringcommittee,knownastheWetlandsWorkingGroup,tooverseeanddirecttheEverestteam.TheWetlandsWorkingGroupincludedstafffromthetwoprimaryfundingagencies,UCNaturalReserveSystemstaff,representationfromFriendsofMissionBayMarshes,andSanDiegoAudubonboardandstaffmembers.

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