Smith River Plain Stream Restoration Plan Del Norte County, California Photos: Kenneth & Gabrielle Adelman – California Coastal Records Project FINAL REPORT TO THE CALIFORNIA COASTAL CONSERVANCY WATER QUALITY, SUPPLY, and INFRASTRUCTURE IMPROVEMENT ACT GRANTEE AGREEMENT: No. 16-027 October 2018 SMITH RIVER ALLIANCE
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Smith River Plain Stream Restoration Plan Del Norte County, … · 2018-11-07 · Stream Restoration Plan Del Norte County, California ... estuaries and other riverine habitats along
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This report was funded by California State Coastal Conservancy with funds from the WaterQuality,Supply,andInfrastructureImprovementAct.TheSmithRiverAlliance(SRA)thankstheDelNorteResourceConservationDistrict forpartneringon thisproject. Inparticular, LindaCrockettprovidedessentialassistancethrougheverystepinpreparingthisplan.Thisprojectwouldnothavebeenpossiblewithoutthecooperationandinputfromtheprivatelandowners.Wearegratefulfortheir willingness to discuss their property, for being stewards of the land, and for consideringadvancement of projects to helpmaintain the health of the Smith River Plain.Wewould like toacknowledgePeterJarauschwiththeStateCoastalConservancy;BobPagliuco,DanFree,andJulieWeederwiththeNationalMarineFisheriesService;JustinGarwood,SethRicker,andMichaelWallacewiththeCaliforniaDepartmentofFishandWildlifefortheirinputontherankingcriteria,theprojectformulation,andforprovidingfeedbackduringtheprocess.WeappreciatetheTolowaDee-ni’Nationstafffortheirparticipationinthisprocess.WethankGordonLeppigforhisinputandknowledgeonriparianrestorationandRossTaylorforhisguidanceonfishpassagecriteria.WearegratefulforthetimeJohnDeibner-HansonandJesseNolanspentinthefieldtosurveyroadcrossingsintheplanningarea.SRAthanksCaliforniaDepartmentofFishandWildlifeand theFisheriesRestorationGrantsProgramforfundingthepriorresearchandmonitoringprojectsthatprovidedthescientificbasisofthisdocument.Finally,thankyoutoSmithRiverAlliancecontributorsforsupportingthisprojectbyprovidingessentialmatchingfundswithmadetheprojectpossible.
“We should not set our sights on rebuilding an environment from the past, but concentrate on shaping a world to live in for the future.” Charles C. Mann
Table 1.Watershed summary information including location of mouth, sub-basin area (squaremiles),estimatedlengthofanadromousstream(meters)andsalmonidusebylifestageforeachsub-basinincludedinplanningarea,DelNorteCounty,CA.Asub-basinisastreamnetworkconnectedbyasinglelinktothemainstemSmithRiver............................................................................................................................5
Table 3. The weights provided by the National Marine Fisheries Service (NMFS), CaliforniaDepartment of Fish andWildlife (CDFW), Del Norte Resource Conservation District (RCD), andTolowaDee-ni’Nation(TDN)averagedandusedintheprojectscoringprocess........................................30
The goal of this planning effort is to identify and prioritize potential restoration projects thatimproveandprotectnaturalchannelstructureandfunction,waterquality,floodplainconnectivity,andbiologicalresourcesalongstreamsandwaterwayslocatedintheSmithRiverPlain.
TheSmithRiverAlliance(SRA)usedstakeholderandlandownerinput,historicandcurrentaerialimagery,topographicandspeciesdistributioninformation,andfieldstudiestoidentifyandcompilealistofpotentialprojects.RankingcriteriawasdevelopedincollaborationwithstafffromNationalMarineFisheriesService(NMFS),CaliforniaDepartmentofFishandWildlife(CDFW),andtheDelNorteResourceConservationDistrict(RCD)thatwasusedtoscoreandrankallidentifiedprojects.Atotal of 137 projects were identified in five projects types: 29 riparian projects, 33 channelcomplexityprojects,63passageprojects,8invasiveplantprojects,and4waterqualityandquantityprojects.
Additionally, there are eight basin-wide recommendations. These are projects that either spanmultiplestreamsandsub-basinsorareareaslackingsufficientdatarequiringfurtherresearchormonitoring.
The project prioritization scores and rankings provide a logical and standardized approach toidentifyingprojectsbasedontheircapacitytorestoreecosystemfunctionsforstreamsandsalmonidpopulations. However, project rankings alone should not set the order of implementation.Landowner interest, professional judgment, opportunities created by scheduledmaintenance orconstruction,andrestorationemphasisbystakeholdergroupsinawatershedshouldbeconsidered.
The historic floodplains and surrounding landscapes of many coastal streams contain theelements needed for human settlement, development, and cultivation of agricultural resources.Theseincludetransportationroutes,watersources,andfertilesoils.Aroundtheworldestuariesandcoastalstreamshavebeenmodifiedandsimplifiedtomeettheneedsofhumansettlementandhaveledtoreducedordamagedhabitatthatisessentialforthrivingfishpopulationsandecosystemhealth(Pavlovskaya 1995, Sommer et al. 2007, Bilkovic and Roggero 2008, Levings 2016). Althoughestuariesandotherriverinehabitatsalongthecoastalplainrepresentasmallfractionofareainagivenwatershed,theirroleinsalmonidproductivitythroughoutthePacificNorthwestissubstantialgiven all anadromous fish use the estuary prior to ocean entry. Low gradient and freshwaterestuarinehabitatssuchassloughs,backwaters,offchannelponds,andemergenttidalwetlandshavebeenshowntobeespeciallyproductiveareasforrearingjuvenilesalmonidsthroughoutthePacificNorthwestandinCalifornia(WissmarandSimenstad1998,Hayesetal.2008,Koski2009,Wallaceetal.2015),includingintheSmithRiverPlain(ParishandGarwood2016).
ThemajorityoftheSmithRiverbasiniscomprisedofsteepforestedterrainwithhighgradientstreams. However, the Smith River Plain is dominated by low gradient streams and sloughssurroundedbygentlyrollingfertilelandthatisprimarilyutilizedforagriculturalproductionofdairy,cattle,andlilybulbs.Dependingonmanagementpractices, theeffectsofagricultureonsalmonidhabitatandnaturalresourcescanvaryfrombeneficialtodetrimental(MooreandPalmer2005,USDA2011,CDFW2015).Well-managedandplannedagriculture isanessentialpartof thesolution toconservingCalifornia’snaturalresourcesandecosystemprocesses(CDFW2015).MultiplesalmonidrecoveryplansthatincludetheSmithRiveridentifytheneedtodetermineprojectsintheSmithRiverPlain that will restore critical salmonid habitats but are also economically feasible (Voight andWaldvogel2002,CDFW2004a,NOAA2014,CDFW2015).RecentmonitoringprovidesabaselineonsalmoniddistributionandhabitatconditionacrosstheSmithRiverPlain(ParishandGarwood2015and2016,WalkleyandGarwood2017)tohelpprojectidentificationandguiderestorationplanning.
Conservationplansshouldconsidertheneedsofthelandandlandowner(USDA2003)inadditiontotheecosystemneeds.Togethertheseconsiderationsshouldbeusedtodeterminethedesiredandpotential future conditions of the ecosystem, social, and economic settings. Landowner andstakeholder involvement is critical in developing area wide conservation plans or assessments(USDA2003).Thisplanningprocessbuildsontherecentmonitoringeffortsandincludeslandownerfeedbacktoimplementaholisticconservationplanningapproachofevaluatingecologicalaswellaseconomicandsocialfactors.Thegoalofthisplanningeffortwastoidentifyrestorationopportunitiesalong anadromous streams. Restoration objectives are focused on restoring stream function, toimprove long-termecosystemhealth, increasewaterquality, support recoveryof salmonids, andprotectbiologicalintegrityandbiodiversityacrosstheSmithRiverPlain.
Thisplanprovidesafoundationofscientificknowledgeandinputfromresourceprofessionalsandlandowners,withconsistentandsubjectiveevaluationofrestorationopportunitiesacrosstheSmithRiverPlain,buttheplanitselfcarriesnoregulatoryauthority.Thisplanningprocesssoughttofollowthe first fourstepsofNRCSnine-stepplanningprocess(USDA2003).Thesestepsare: (1)identifyproblems,(2)determineobjectives,(3)inventoryresources,and(4)analyzeresourcedata.
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ThisplanwillsupportthenextfivestepsoftheNRCSprocess,whichinclude:(5)formulatingand(6)evaluatingalternatives,(7)makingdecisions,and(8)implementingand(9)evaluatingtheplanandresultingactions(USDA2003).Theseplanningstepsdonotneedtobeconductedlinearlybutallstepsarevitalforsuccessfulconservationplanning(USDA2003)andinformfutureactionstoensuredesired future conditions are achieved. This process provides the building blocks needed tounderstandtheproblems,opportunities,solutions,andresultsoflandscapechanges.
Thebiologicalandphysicalstructureofawatershedisshapedbybothlongitudinal(upstreamtodownstream)andlateral(streamtoterrestrial)linkagesandrestorationprojectsmustconsiderthesurroundinglandscape,notonlythereachwheretheprojectmayoccur(Beechieetal.2008,Lake et al. 2007).Restorationactionsthatconsiderwatershedandecosystemprocessesaremorelikelytosucceedatreachingrecoverygoalsandpreventingfurtherspeciesandhabitatdeclinesthanactionsfocusedonlyonrestoringwatershedform(Reevesetal.1995,Beechieetal.1996,Bradburyetal.1995,NOAA2014).Finally,salmonandotherwildlifehaveadaptedtonaturallocalvariationatbothspatial and temporal scales. Therefore, restoration should not require for conditions to remainconstantatasinglelocationoruniformacrossthelandscape(Bradburyetal.1995).
The highest priority projects, with the highest likelihood of implementation, are those thatprovidemultiplebenefits tonaturalresourcesandarecompatiblewith the landownerneedsandoverallmanagementplans(USDA2003).SmithRiverAlliance(SRA)usedscientificliterature,historicimages,speciesdistributions,topographicassessment,landscapeconditions,andlandownerinputtoidentifypotentialrestorationopportunities.Weevaluatedpotential fishbarriers,theconditionofriparianvegetation,hardenedbanks,impervioussurfaces,anddiversionstofurtherdevelopthelist.Rankingcriteriawasdevelopedtoaidinarelativeprioritizationbetweenidentifiedprojects.Rankingscores estimated the biological and ecological resources that would be benefited as well as theintegrity,risk,optimismandpotentialofaproject.
Theinformationinthisplanshouldbeusedbyinterestedpartiestosupportwillinglandownersintheformulationofrestorationalternativesandtodevelopprojects.Adaptivemanagementshouldbeused to forecastproject effectiveness and identify any additional steps areneededto achieveprojectgoals.
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SmithRiverPlainBackground
TheSmithRiveristhenorthernmost,coastalwatershedofCalifornialocated3.7milessouthoftheOregonborder(Figure1).TheSmithRiverPlainis79.31squaremiles(Table1)andconsistsoftwoformationsincludingSaintGeorgeformationandBatteryformation(Robertsetal.1967).TheSaintGeorge formationiscomposedofbioturbatedmarinesandstoneandsandymudstonemixedwithpebbles, carbonizedwood, and fragmentedmolluscan shells (Delattre and Rosinshki 2012). TheBatteryformationformedfrommarineterracedepositsmixedwithdunesandsandalluvialgravels(Delattre and Rosinshki 2012). These formationswere shaped by alluvium deposited over landhistoricallyconnectedtothecoastrange,whichseparatedandsankintothesea(Monroe1975).Thealluviumwasfurthermoldedandsmoothedbywaveactionandoceancurrents.Sinceformationoftheplain, theSmithRiverchannelhaserodedcreating thecurrentdaycoastalterrace.Above thecoastalplain,approximatelywhereHighway101crossestheriver,theactivechannelissurroundedbysteeperforestedterrainintheFranciscanformation(Robertsetal.1967).Theplanningareaischaracterizedbylowgradients,awidevalleyandanalluvial fanbedformwitha large floodplain,resultingindepositionofmobilizedsedimentdeliveredfromupstream.
TheSmithRiverbasin receives an impressive91.59 inchesof rainfall annuallyat theGasquetRanger Station and 64.03 inches at the Crescent City McNamara Field Station (CDEC 2017).Precipitation is usually deliveredduring largewinter storm eventswith 82% of annual averagerainfallreceivedoccursfromOctobertoMarch(CDEC2017).
Thesparselyvegetatedandshallowrockysoilsthroughoutmostoftheinteriorbasinholdlittleprecipitationandstreamsrapidlyrespondwithhighlyvariableflows.Averageannualpeakflowfrom1927 to2016 is 82,495 cubic feetper second (cfs) (USGS2017a) resulting inan estuary largelyformedbyriverdominatedhydrologicalprocessesduringthewintermonths.Asflowreachestheminimumduringthelatesummer(meanmonthlyAugustflow=338cfs),oceantidespushsaltwaterupstreamresultinginseasonallyvariedconcentrationandextentofmixingocean-freshwaterandsaltwedge(Mizuno1998,ParishandGarwood2015&2016).Theseabioticconditions,coupledwithwaterquality,nutrientconcentrations,grassandalgalcover,andspecieslifehistories,resultinthedensity,diversity,anddistributionofsalmonidsandotherbiotavarywidelyinthecoastalplainonaseasonalbasis(Parthree2004,Dayetal.2013,ParishandGarwood2016).Inadditiontosalmonids,multipleplant,fishandwildlifespeciesseasonallyutilizeestuarine,stream,wetland,andriparianhabitatsacrosstheSmithRiverPlain(Monroe1975).
Theplanningareaincludesthemainstemandanadromoustributarieslocatedwithinthecoastalzone(Figure1).WithinthisareaisthetownofSmithRiver,locatedneartheconfluenceofRowdyandDominieCreeks, contains themajorityof developed residential and industrialparcels in theplanningarea.Asof2010,thepopulationofSmithRiverwas866(USCB2010).Thelandscapeofthe
Table1.Watershedsummaryinformationincludinglocationofmouth,sub-basinarea(squaremiles),estimatedlengthofanadromousstream(meters)andsalmoniduseby life stage foreachsub-basin included inplanningarea,DelNorteCounty,CA.Asub-basinisastreamnetworkconnectedbyasinglelinktothemainstemSmithRiver.
Islas Slough 400771 4642656 1346 0.84 included in mainstem Yes No
Tryon Creek sub-basin 12769 7.93 5.79
Yontocket Slough 400884 4640643 2662 1.65 Yes Yes
Tryon Creek 402384 4639744 9425 5.86 Yes Yes
Unnamed Tryon Creek Tributary 402651 4638092 682 0.42 Yes No
Rowdy Creek sub-basin 8729** 5.42 34.08
Rowdy Creek 403256 4640720 6791** 4.22 Yes Yes
Dominie Creek 405150 4642412 1160 0.72 Yes Yes
Clanco Creek 405001 4641708 778 0.48 Yes No
Morrison Creek sub-basin 10090 6.27 3.69
Morrison Creek 403625 4640478 4720 2.93 Yes Yes
Mello Creek 404351 4639775 2911 1.81 Yes Yes Unnamed Morrison Creek
Tributary 405124 4639922 2459 1.53 Yes No
Stotenburg Creek sub-basin 2522 1.57 0.75 Yes No
Stotenburg Creek 404802 4638092 1994 1.24
Unnamed Stotenburg Creek Tributary 405410 4637529 528 0.33
Total 60283 37.46 79.37 * Does not include Coastal Cutthroat habitat
** excludes anadromous stream upstream of South Fork Rowdy Creek
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SmithRiverPlainispredominatelyutilizedforagriculturalpracticesincludingcattleranching,dairyproduction,andlilybulbproduction.AtimbermillwasactivelyoperatedinthetownofSmithRiveralongRowdyandDominieCreeksbeginninginthemid-1940’s(GHD2015).Bythemid-1990’sandpresentdaythemillisnolongeroperationalthoughtimberharvestcontinuesinthearea.Theselanduses(i.e. residential,agriculture, timberoperations)haveresulted inmodifications to thestreamform,capacity,sedimenttransport,habitatavailability,andpollutionlevelsofthewaterwaysintheSmithRiverPlain.Forexample,leveeconstructionandbankarmoringthathaveresultedinsimplifiedandhigh-energychannels(GHD2015,ParishandGarwood2015).
RecentwaterqualitymonitoringdocumentedthepresenceoflegacyandcurrentlyusedpesticidesanddissolvedcopperintributariesoftheSmithRiverPlain(CWB2018,NOAA2018a).Pesticidesandcopper areused inproductionof lily bulbs to control diseaseandnematodes in the SmithRiver(VoightandWaldvogel2002,CWB2018).Copperisaknownneurobehavioraltoxicantforsalmonids(NOAA2018a). Recentwaterqualitytestingfoundthatcopperlevelswerehigherbelowlilybulbfieldsthanabovefieldsinsomestreamslocatedintheplanningarea(NOAA2018a).Whilecopperisusedforproductionoflilybulbs,copperisalsonaturallypresentintheSmithRiverandsamplingdoes not solely attribute bulb production for copper presence (NOAA 2018a). Bulb productionincludes tilling andsoil disturbance in the fall leaving fields vulnerable to erosionduringwinterstorms.Withoutadequatebufferstripselevatedsedimentlevelsmaybereachingstreams.
No Total Maximum Daily Loads (TMDLs) have been set and no continuous monitoring isimplementedtodeterminelevelsorexactsourcesofimpactstowaterquality.However,underorderno.R1-2012-003andR1-2012-002,beginningin2013allcowdairiesinCaliforniaarerequiredtohaveanutrientmanagementplanandannualmonitoringofsurfaceandgroundwateraspartofwastedischargerequirements(DNUDA2013).Thismonitoringevaluatesturbidly,temperature,pH,conductivity,andammonianitrogenofallsurfacewatersimpactedbydairyoperations.Nitrateandfecal coliform bacterial levels in groundwater is alsomonitored. Themonitoring and reportingsystemscontaininformationofwaterqualityconditionsandallowslandownertotakeactionsaimedat improving conditions. Recent water quality sampling conducted documented surface watersamples with U.S. EPA nutrient criteria for total nitrogen and phosphorus exceeded inmultiplestreamslocatedintheplanningarea(CWB2018).
RowdyCreekFishHatchery,locatedattheconfluenceofRowdyCreekandDominieCreek,isonlyoneof twoprivatelyoperatedfishhatcheriesrunbynon-profitsinCalifornia.Thepurposeof theRowdyCreekFishHatcheryistoincreasethenumberofcatchableChinookSalmonandSteelheadintheSmithRiverfishery(Zuspan2018).WatertemperatureanddissolvedoxygenismonitoredwithinthehatcherytanksbutnottheeffluentdeliveredtoRowdyCreek.CaliforniaDepartmentofFishandWildlife (CDFW) manages the other 24 hatcheries in the state and requires National PollutantDischargeEliminationSystem(NPDES)permitsfromRegionalWaterQualityControlBoarddistrictstoensureoperationsdonotharmwatersreceivinghatcheryeffluent.RowdyCreekHatcheryalsoobtainsahatcherytrappingandrearingpermitasrequiredbyFishandGameCode.
The ancestral lands of the Tolowa Dee-ni’ Nation (TDN), a federally recognized Indian Tribe,includes theentiretyof theSmithRiverbasin.Thecitizensof theTDNcontinue torelyupontheresourceswithintheSmithRiverPlain.TheTDNplaceofGenesisandworld-renewalceremony
location,Yontocket (Yan’-daa-k’vt), is locatedwithin theplanningarea, see theYontocket Sloughsectionbelowforadditionalinformation.
Thereare47.5milesofpotentialanadromousstreamhabitatincludedintheassessment.ThiswasdeterminedbasedontheprotocoldescribedbyGarwoodandRicker(2011)withamaximumstreamgradient equal to or less than 8% using intrinsic potential stream lines (Burnett et al. 2007).Adjustments were made where needed based on documented salmonid observations includingcoastalcutthroattrout(Oncorhynchusclarkii)distributionsandknownfishbarrierlocations.Parishand Garwood (2015 and 2016) have documented coho salmon (Oncorhynchus kisutch), Chinooksalmon(Oncorhynchustshawytscha),steelheadtrout(Oncorhynchusmykiss),andcoastalcutthroattroutthroughoutthisareaduringboththesummerandwintermonths.Monitoringhasshownthatthere isseasonalvariationofhabitatuse in theplanningarea.Predominantly themainsteamandprovidesimportantsummerrearinghabitatwhilethetributariesprovidevitalwinterrearinghabitat(ParishandGarwood2015).Whilenotallstreamsinthisareaflowyear-round,juvenilesalmonids,includingnon-natalrearingMillCreekspawnedindividuals,havebeendocumentedrearinginthecoastal tributaries while surface water is present during the winter; from early winter (lateNovember)throughspring(mid-May)(ParishandGarwood2016).Furthermore,areaswithwaterqualitythatiswithintolerablerangesofdissolvedoxygen,temperature,andsalinityprovidesummerrearinghabitat(ParishandGarwood2015).
FromthemouthofRowdyCreektodownstreamoftheTillasSloughmouth,leveeconstructionbeginningintheearly1970’shasresultedinaconfinedchannelwithreducedoff-channelhabitat,depositional areas, and connection to small drainages evident from the presence of riparianvegetationinthe1942aerial image(Figure3).UpstreamofRowdyCreekthemain-channelturnssoutheastandtheaveragegradientincreasesresultinginlongriffleandrunhabitatsseparatedbyafewdeeppools.Thetidalsaltwedgeextends4.75miupstreamfromthemouthduringthesummer(ParishandGarwood2015)and1.09miduringthewintermonths(ParishandGarwood2016).
Themain-channeldownstreamoftheRowdyCreekconfluencehashadthelargestchangewiththesouthernbankmigratingmorethan850feettothesouthatthemouthofYontocketSloughfrom1942to 2016. The levee located on the north bank upstream of the Yontocket Slough confluence,constructedafterthe1964flood,possiblyacceleratedthislateralmigrationofthesouthbank(Love2006).Erosiononthesouthbankcontinueswithapproximately20ftofsouthernmigrationinthelast4years.
The1972floodbroketheleveeacrossthesloughandwasrebuiltwithtwotidegates,whichhavesincerustedandnolongerfunctionastidegates,allowingforunregulateddailytidalwaterexchange(ParishandGarwood2015).Therearetwo‘legs’ofthesloughwithalltributariesflowingintotheeastleg.Thetwolegscontain2.99milesofanadromousstream.Thesloughisdominatedbysilt,withgravels present particularly in the upper half of the west leg. Reed canary grass (Phalarisarundinacea) is prevalent in the upper end of the east leg and at the confluence with all threetributaries.
Theuplandareas thatdrain into the slough aredominatedbypasture landand lilybulb fields.JuvenileChinooksalmon,cohosalmon,unidentifiedtroutspecies(Parthree2001),tidewatergoby(Eucyclogbiusnewberryi) (Schmelzle2015), baypipefish (Syngnathus leptorhynchus), coast rangesculpin(Cottusaleuticus),surfsmelt(Hypomesuspretiosus),andthreespinestickleback(Gasterosteusaculeatus)havebeendocumenteddownstreamofornearthelevee(ParishandGarwood2015).Themajorityofthelandinthesub-basinisutilizedforcattle,dairy,andlilybulbproduction.
with an estimated 1.96miles of anadromous stream. Some intact riparian vegetation is presentthroughout much of the channel and spawning substrates are present above Highway 101 andextendingaboveOceanViewDrive.Coastalcutthroattroutandjuvenilesteelheadtrouthavebeendocumented in Ritmer Creek and the stream likely supports all salmonid life stages (Parish andGarwood2016). Dense reed canary grass is present at themouth, limiting fish passage, channelcapacityandwaterquality.
DelilahCreekDelilah Creek is the longest tributary of Tillas Sloughwith 2.02miles of anadromous stream
sidechannel(Figure3).Basedonaerialimagery,IslasSloughencompassed71acresin1942andonly12acresby2012(ParishandGarwood2015).Theupperendofthesloughisdisconnectedbyaleveenetwork, built in the 1960’s and 70’s, along the western and upstream margins of the sloughpreventing Smith River flows from flushing through the slough and connecting to the southernportionofTillasSlough(Figure3).The lackofelevationdifference inthisareapreventsaccurateestimate of the basin area. No streams flow directly into the slough, rather the slough receivesdrainagefromthesurroundingagriculturalfields,andthroughvaryingflowsandtidalinfluencesofthemainstemSmithRiver.Thechannelisdominatedbymixedcobbleatthemouth.Theuppersloughisdominatedbygravel anddeposited silts.Nativeriparianandwetlandvegetationdominate thefringeofthechannelthoughcanaryreedgrassispresentonthefringesattheupstreamendofthe
ThedownstreamhalfofthesloughislocatedwithintheTolowaDunesStateParkandisanarealistedon theNationalRegisterofHistoricPlaces. Yan’-daa-k’vt (Yontocket) is the locationof theGenesisoftheTolowaDee-ni’.ThisculturallysignificantareaisalsoanimportantTolowaDee-ni’wintervillage,alsoknownasYan’-daa-k’vt,locatedtothewestofthesloughinthepresentdayStatePark.In1853,earlysettlersambushedandmassacredpeopleintheYan’-daa’k’vtvillageduringaceremony.Ancestralremainsandculturalresourcesarelocatedbothintheareaandintheslough.Duetothemassacre,theareaisalsoknownasBurntRanch.LateritwasknownasthePalaPlace,andtodayistheYontocketMemorialVillage(Gould1984)andisactivelyusedasatribalcemetery.
PriortoandduringearlyStateParkownership,grazingoperationsoccurredaroundtheslough.Morerecently,theareawasmanagedwithcattlegrazingtoaidinrecoveryoffederallyprotectedAleutiancacklinggoose(Brantahutchinsii leucopareia).Nograzinghasoccurredintheparksince2011.PalaRoad,builtprior to1942, is located0.25milesupstreamfromthemouth, resulting inalteredhydrologyandincreasedsedimentationintheslough.Inthe1990’sandearly2000’s,waterelevationwasmanagedatPalaRdtoincreaseopenwaterhabitatduringwaterfowlhuntingseason(Love2006).Reedcanarygrasshasfurtherincreasedsedimentation,negativelyimpactingsalmonidhabitatbyreducingfishpassageandwaterqualityinmultiplelocationsthroughoutthesloughandinTryonCreek.DairyoperationsarelocatedupstreamoftheParkboundaryonthesloughandalongthemajorityofTryonCreektoHighway101.UpstreamofHighway101TryonCreekissurroundedbyresidentialdevelopmentwithtimberharvestoperationslocatedintheheadwaters.
Nativeriparianvegetationislimitedbydensereedcanarygrassborderingandencroachingintothemajoritytheslough.Indeeperareasofthesloughyellowpondlily(Irispseudacorus)ispresentandpatchesofwillowandSitkasprucearepresentinmultiplelocations.Riparianrestorationeffortsfunded by CDFW and SCC occurred in 2011 to enhance riparian vegetation and cattle exclusionfencinginpartsofthebasin(Love2006)thoughcanopycoverremainslowandreedcanarygrassisstillpresentthroughoutmuchofthechannelfromYontocketSloughtoMoseleyRoad(ParishandGarwood2015).
JuvenilecohosalmonhavebeendocumentedusingYontocketSloughandTryonCreekforwinterrearing, including non-natal rearing, based on detection of marked juvenile coho salmon thatmigratedfromMillCreek(ParishandGarwood2016,Walkleyetal.2017).Nearandupstreamof
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Highway 101, where there is perennial water, juvenile coho salmon, Chinook salmon, coastalcutthroattrout,andunidentifiedtrouthavebeendetectedduringthesummermonths(WalkleyandGarwood2017).
HistoricaerialimagesshowRowdyCreekhavingabraidedchannelinmanylocationsandalargealluvialfanatthemouth.Theupperwatershedismanagedfortimberproductionwithtimberharvestregulation andanAquaticHabitatConservationPlanproviding streamprotectionand regulationguidelines. The lower watershed is primarily managed for agricultural uses as well as someresidentialpropertiesliningthestreaminthetownofSmithRiver,neartheconfluenceofRowdyandDominie Creeks.Multiple channel alterations have occurred over the years resulting in reducedchannelarea,lossoff-channellowvelocityrearinghabitat,andlessfloodplainconnectionduetobothagriculturalandtimberproductionpractices,particularlyinthelowerwatershed.
Rowdy Creek and Dominie Creek have experienced additional channel confinement directlyupstreamofHighway101duetohistoricandcurrentmilloperations.Basedonhistoricaerialimages,between1942and1948themilloperationalongRowdyCreekincreasedinthisareaandmultiplebuildings and channel alterations with rip rap bank armoring were constructed. By 1958, themainstemofRowdyCreekandDominieCreekalongthemillsiteresultedinchannelconfinement,lossoffloodplainconnection,andreducedoverallsinuosityofthechannelprofile.Priortochannelmodificationsformillinfrastructure,thisportionofRowdyCreekhadawidevalleyandadynamicmeanderingchannel(GHD2015)thatlikelyprovidedmultipleoff-channelandslowwaterhabitatsduringhighwinterflows.DominieCreekwassurroundedbydensevegetationthoughthechannelform and width are not well identifiable in the early historic images. By 1972, a cleared andstraightenedstreamchannelisidentifiableastheriparianvegetationhasbeenclearedandthemilloperationexpandedintheadjacentfloodplain.
Afishhatcheryfacility(RowdyCreekFishHatchery)operatesattheconfluenceofDominieandRowdy Creeks with infrastructure that creates a total of three fish barriers combined on bothstreams,aswellasextensivebankandchannelarmoring.ThehatcheryweiracrossRowdyCreekisoneofthemostsubstantialanadromousfishbarriersremainingincoastalCaliforniaoutsideofmajordams(ParishandGarwood2016).ThehydraulicconditionscreatedbytheconcreteapronacrossRowdyCreekcreatesacompletebarriertojuvenileupstreammigration(GHD2015).Thediversionweirandconcreteapronalsopresentpassageissueforadultsalmonids,evenwhenthehatcheryis
Themajority of the agricultural production in the basin occurs downstream of the hatchery.Alterationsdownstreamofthehatcheryincludingbankarmoringwithriprapanddisposedcars,andleveeconstructionhasledtofurtherchannelconfinement, lossofriparianhabitat,andfloodplainconnection.GHDfounda43%lossofchannelareafromHighway101tothemouth(2015).Alossinchannel area results in increase stream velocity and sediment transport, transforming the oncedepositionalchannelreachintoatransportreach(GHD2015).
MorrisonCreekMorrisonCreek sub-basin encompasses3.69 squaremiles andhas an estimated6.27milesof
anadromous fishhabitat.Multiple tributaries are locatedwithin the sub-basin, the two largest ofwhichareMelloCreekandanunnamedstream(aka.RawsonCreek).Spawninggravelsandrearinghabitat are present throughout the majority of the basin. Coho salmon have been documentedthroughoutMorrisonCreekanditstributariesuptoHighway101(GarwoodandLarson2014,ParishandGarwood2016).JuvenilecohosalmonandtroutthatoriginatedinMillCreekhavebeendetectedutilizingMorrisonCreekduringthewintermonths(ParishandGarwood2016).JuvenileandadultChinooksalmonandcoastalcutthroattrouthavealsobeendocumentedintheMorrisonsub-basin(GarwoodandLarson2014,WalkleyandGarwood2017).
Themajority of the upperwatershed aboveHighway 101 ismanaged for timber production.Residentialdevelopmentispresentupstreamofthehighwayasthestreamleavesthesteepforestedhillsideandjoinsthecoastalplain.Downstreamofthesmallresidentialareas,themajorityofthebasinisutilizedforcattle,dairy,andlilybulbproduction.Asthedrainageleavesthesteepforestedhillsidethechannelgradientisreducedandentersadepositionalzone.Annualfloodingispresentinmultiplelocations inthebasin,particularlydownstreamofHighway101andaroundFredHaightDrive.BothMelloCreekandMorrisonCreekmeetFredHaightDriveat>45°bendsinthechannelresulting in a loss of the streams ability to transport sediment and water, leading to channelaggradation, exacerbating localized flooding along the county road and surrounding properties(Smelser2013,Love2018).
Historic landusepracticeshave led toreducedchannelcapacityandchannelsimplification inmany locations.Riparianvegetation is present inmany locations throughout thebasin though islacking inareaswithcattleaccess to thestreamalongmultiplereaches.Lackofchannelcapacityresultsinregularfloodingfromthemainchannelaswellasalongthetributariesandoverlandflowacrossadjacentagriculturalfields.A0.3squaremilepond,Goodwinpond,locatedintheMorrisonCreeksub-basin,capturesmultiplespringsandholdswateryear-round.GoodwinPondwasformedinthe1950’swiththeconstructionofleveesadjacenttoFredHaight.OutflowentersMelloCreekupstream from Fred Haight Drive with limited fish access. North American Beavers (Castorcanadensis)utilizethepondhabitataswellasMorrisonCreek.
Thissection lacksnativeriparianvegetationandhasbaresoilon thesurrounding fields insomeyears. Reed canary grass and the low gradient of the channel result in deposition of deliveredsediment.Thisdepositionhasledtorecentchannelmigrationandlossofwinterrearinghabitatforjuvenile salmonids (Parish andGarwood2016).The unnamed stream is composedof four smallstreamsoriginatingeastofhighway.Thesefourstreamsmergedownstreamof,butnearHighway101 to flow through a forested landscape dominated by Coast Redwood (Sequoia sempervirens)beforecrossingpastureandmeetingMorrisonCreek.
0.75squaremilesandcontainsanestimated1.57milesofpotentialanadromousstreamhabitat.Thesub-basincontainstwointermittentstreamsthatoriginateintheforestupstreamofHighway101and merge downstream after flowing under South Fred Haight Drive. Juvenile coho salmon,unidentifiedtroutandcoastalcutthroattrouthavebeendocumentedinthestreamuptoFredHaightDrive(GarwoodandBauer2013,ParishandGarwood2015&2016).StotenburgCreekhasmixedlandusewiththeheadwaterscomprisedofresidentialandtimberharvestpropertyandthelowerbasin parcels used for horse pasture anddairy cattle ranching. Stotenburg Creek typically driesduringthesummermonthsandflowssubsurfaceatthemouthduringthespringandearlywinter.NorthAmericanBeaversutilizeStotenburgCreekandhavebuiltsmallchannelspanning(<1ft)damsinvariouslocationsalongthechannelduringrecentdecades(ParishandGarwood2016,L.J.Ulrichpersonalcommunication).FinesedimentdominatesthechannelwithsomegravelspresentintheupperreachesnearHighway101.
Roadcrossings,waterdiversions,riparianvegetation,elevation,hardenedbanks,andimpervioussurfaceswereassessed to identifypotentialprojects.Additionally, SRAmetwith landownersandnaturalresourcespecialistsfromCDFWandNMFStorefineandeditthelistofpotentialprojects.Evaluationswere conducted for each streamand sub-basins arenumbered fromdownstream toupstream.
LowImpactDevelopmentLand use change can alter aquatic environments through construction of roads, impervious
surfaces, levee/dikenetworks,streambankarmoring,streamchannelstraightening,andwetlandfilling. Developmentcanmodifymultiplenaturalprocessesacrossthe landscape thatarevital tomaintainhighwaterqualityandaquatichabitat(CDFW2014).Theseincludebutarenotlimitedto:altered water infiltration rates, stormwater runoff, reduced habitat availability, quantity andtransport of pollutants, nutrient cycling in the aquaticand terrestrial environment, and stream -floodplaininteractions.
Channelmigrationisanimportantnaturalstreamprocessthatcreatesandmaintainsoff-channelhabitat through the recruitment and sorting of sediments and large woody debris. Channelstraightening, levees,andbankarmoringstabilizechannels,whichcanleadtochannelincisionoraggradation due to changes in sediment andwater transport rates. Impervious surfaces reduceinfiltrationcapacityandincreasesstormwaterrunofftonearbywaterways,bothofwhichresultinreducedwaterqualityinbothsurfaceandgroundwater.Roadcrossingscanrestrictchannelwidthsreducingtheirconveyancecapacityofwater,sediment,andnutrients,whichcanleadtofloodingandapassagebarrierforaquaticspecies.
MuchoftheSmithRiverPlainisutilizedforagriculturalproductionandhaspervioussurfaces.However, historic development has altered the stream channels and floodplains in the region.Residentialandindustrialdevelopment,particularlywithinthetownofSmithRiver,hasresultedinareasof impervious surfaces.Unusedpavedsurfaces remainwhere theold timbermill operatedalong Rowdy andDominie Creek resulting in increased runoff, reduced infiltration, and channelconfinement.TheselandscapemodificationshavealteredallstreamswithintheSmithRiverPlain.
Low impact development (LID) techniques such as rainwater gardens, pervious surfaces fordrivewaysandwalkways,greenroofs,andvegetatedswalescancaptureandincreasestormwaterpercolation andwaterpurification(USEPA2000). Increased connectionbetween the streamandfloodplaincanreducefloodingandprovideimportantsalmonidhabitat.LIDtechniquesthatfocuson
LowImpactDevelopmentMethodsAerial images from1942to2016were evaluated to identify areaswith changes to the active
channel, floodplain, and locations of channel straightening. Locations with armored banks andlevee/dike networks were identified through field surveys, Parish and Garwood (2015) andlandownerfeedback.Impervioussurfaceswereidentifiedwiththe2011NationalLandCoverDatasetforCalifornia(USGS2011),crossreferencedwithU.S.CensusBureau’sroadlayer(USCB2015),andU.S. Agricultural Department 2016 aerial imagery (USDA 2016). Using a CDFW recommendedriparianbufferwidthof164feet(seeRiparianEnhancementsection),allidentifiedhardenedbanksandlevee/dikenetworkswithinthisbufferfromtheedgeofthestreamchannelwereincludedaspotentialrestorationareas.Lastly, impervioussurfaceswithinthe164ftbufferwereidentifiedaspotentialprojectsforimplementingLIDtechniques.
Anadromousspeciesareparticularlyinfluencedbycrossingsastheymigratethroughastreamnetworkatmultiplelifestages(CDFW2004b).Generally, juvenileandadultsalmonidsattempttopass crossings after elevated flow events, on the descending limb of a hydrograph, with adultsattemptingathigherflowsthanjuveniles(Langetal.2004).Theheightofthecrossingoutletandflow conditions in and adjacent to a crossing, can completely or partially prevent fish passage.Crossingsthatarefishbarrierscanbeclassifiedas:temporal-impassabletoallfishatcertainflowconditions;partial-impassabletosomefishspeciesduringsomeoralllifestagesatallflows;ortotal–impassabletoallfishatallflows(CDFW2004b).
Allfishbarrierslimitthequantityofavailablespawningandrearinghabitatupstream,therebyreducingthepotentialfishproductivityinastreamsystem,andcauseincreasedenergyexpenditure,potentiallyleadingtoincreasedpredationandreducedspawningsuccess(CDFW2004b).Advanceshavebeenmadeovermanydecades inassessing,upgradingandreplacingcrossings intheSmithRiverupstreamofthePlain.Asaresult,todaytherearefewmanmadebarriersoutsideoftheSmithRiver Plain. However, dozens of crossings in the Smith River Plain have not been assessed orupgradedforfishpassage.
upstream and downstream movements (Parish and Garwood 2016, Walkley et al. 2017). Roadcrossingshavethepotentialtocompletelyblockaccessorlimittemporalaccesstotheseimportantrearinghabitats.
Crossings often also restrict passage of non-salmonids such as adult Pacific lamprey. Passageassessmentsandupgradedesignsconsiderthejumpheightandwatervelocitiesaroundtheculverttoconsiderpassageneedsofvarioussalmonidspeciesandlifestages(CDFW2004b).Forexample,lampreyareunabletojumpifthereisanyverticaldropattheoutletandtheyhavedifferentneedsregarding flowvelocity, restingareasandattachment substrates(GoodmanandReid2012).Thesuctiondiscmouthofalampreyisunabletoremainattachedwhilenavigatingoversharp(≥90°)angles commonly foundon crossings such ason concrete apronsof culverts (GoodmanandReid2012).Forthisplan,anassessmentwasconductedatallcrossingslocatedwithintheplanningarea,where access was granted, with the goal of identifying all barriers to anadromous fish species,includingPacificLamprey.
CensusBureau2015roadinventorylayer,whichincludesfeaturesrangingfromtrailstohighways,wasviewedinArcMap10.3.1(ESRI2017).AllroadsnotlistedbyUSCB(2015)butvisibleonthe2016NationalAgriculturalImageryProgram(NAIP)image(USDA2016)wereaddedtotheroadslayer.TheresultingupdatedroadlayerwasthenoverlaidwiththeCDFWanadromousfishstreamslayer.All intersections between the roads and streams were identified to develop a list of potentialcrossings.Lastly,eachstreamwasviewedinGoogleEarthinadownstreamtoupstreamdirectiontoassessthepresenceofcattlecrossingsnotnecessarilylinkedtoaroadnetwork.
The stream crossing list was then cross-referenced with the California Passage AssessmentDatabase (PAD) (CDFW 2018) and Del Norte County Road Department records to compileinformation on fish passage status and records of past surveys conducted at stream crossingsthroughout the Smith River Plain. The presence and condition of each identified crossing wasdiscussedwithlandownersandDelNorteCountyRoadsstaff.LandowneraccessrequestsweremadeforallcrossingsnotidentifiedinthePADorhistoricallysurveyed.Whereaccesswasgranted,fieldsurveyswere conductedusingCDFWprotocol inPart IXof theCaliforniaSalmonidStateHabitatRestorationManual(CDFW2004b).
All crossings identified aspotential barriers (Grey)were further evaluatedusing theFishXingprogram(Version3;USFS2012).Designingstreamcrossingstopassallfishspeciesandsizesatallflows is technically and economically infeasible (CDFW 2004b, NOAA 2001). Accordingly, fishpassagedesignflows(Table2)areusefulforevaluationoftheflowsatwhichdifferentspeciesandlifestagesrequireaccessatpotentialproject locations.Fishpassagedesign flowsare intendedtoencompasstherangeofflowsthattargetfish(i.e.,speciesandlifestage)encounterwhentheyareexpectedtomigrateupstream.Usingthehydraulicdesignmethod,weused1cfs,2cfs,and3cfsforthe lower fish passage flow for juvenile, non-anadromous salmonids, and adult salmonids,respectively,duetoalackofflowdurationdata(CDFW2004b).Weused10%,30%,and50%ofthe2-yearreturnperiodflowfortheupperfishpassageflowforjuvenile,non-anadromoussalmonids,andadultsalmonids,respectively,alsoduetoalackofflowdurationdata(CDFW2004b).
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Table2.Californiafishpassagedesignflows(CDFW2004b,NOAA2001).Fish Species or Life
stage Lower Fish Passage Design
Flow Upper Fish Passage Design
Flow Adult Anadromous
Salmonids 50% exceedance flow or 3 cfs
whichever is greater 1% exceedance flow or 50% of
the 2-year return period flow Adult Non-
Anadromous Salmonids 90% exceedance flow or 2 cfs
whichever is greater 5% exceedance flow or 30% of
the 2-year return period flow
Juvenile Salmonids 95% exceedance flow or 1 cfs whichever is greater
10% exceedance flow or 10% of the 2-year return period flow
Peakflowcapacityofacrossingwasusedtoevaluateacrossingsriskoffailureathighflows.FlowcapacityofcrossingsweredeterminedusingthosepresentedbyCDFW(2004b)basedontheculvertsize and inlet configuration and calculated using Piehl et al. (1998). NOAA (2001) guidelinesrecommend crossings be able to accommodate the 100-year storm flowwithout damage to thestreamcrossing.CDFWguidelinesrequiretheupstreamwatersurfaceelevationtonotexceedthetopoftheculvertinletforthe10-yrpeakfloodandheadwatershouldnotbegreaterthan50%oftheculvertheightordiameterabovethetopoftheculvertinletforthe100-yrpeakflood(CDFW2009).Stream-specifichydrologyand2-,5-,10-,25-,50-and100-yearflowsweredeterminedusingUSGSstreamstats(USGS2017b).RefinementsweremadetothebasinboundarieswhenneededbasedontopographicrelieflinesevaluatedusingUSGStopographicmaps.Basedontheanalysis,allcrossingsthatwere found to limitpassageof anadromous species, confine the channel, orwereunable toaccommodatethe100-yearflowwereincludedintheprojectlist.
facilitating natural physical, hydrologic, and ecological processes that form and maintain waterqualityandhabitatfornativefloraandfauna.Riparianareasprovideanecologicallinkandtransitionbetween aquatic and terrestrial environments. This area can be referred towithmultiple termsincludingriparianbuffer,vegetatedbufferstrip,riparianzone,ripariancorridor,andriparianhabitat.Regardless of the term used, it is the area through which surface and subsurface hydrologyinterconnectaquaticareas,(i.e.,streams,wetland,andsloughs)withtheadjacentterrestrialuplands(Brinsonetal.2002,SWRCB2012).Inthisreport,riparianareaisazonesetasidefromharvestorothereconomicuse,unlessotherwisespecified.Furthermore,allbufferwidthsdiscussedrelatetotheperpendiculardistanceoneachsideofthestreamstartingattheedgeoftheactivechannel(i.e.,30ftbufferequalsatotalof60ftofriparianhabitat).
Riparian zones arewidely recognized to provide numerous important functions that supportnaturalstreamprocessesandahealthyaquaticecosystem(NaimanandDecamps1997,Naimanetal.2000).Inparticular,riparianzonesperformatleastfivecriticalfunctionsformaintainingnaturalphysical stream processes: 1) stabilize stream banks; 2) regulate water temperature and localmicroclimate; 3) filter pollutants; 4) provide instream wood; and 5) moderate stream andgroundwatervolumes.Whilemanyoftheseprocesses indirectlybenefitthe local floraand fauna,riparian zones perform additional functions that directly benefit biological processes. Habitat
Governmentalagenciesandothersrecognizethesignificanceofriparianzonesinprotectingwaterquality and aquatic habitat, acknowledging the need to protect and restore these ecologicallyvaluable areas (CDFW2015,CNRA2016, SCC2018). Locally, theDelNorteCountyGeneralPlan(2003)recognizesripariancorridorsasmajorlocationsofexcellentwildlifehabitatthatshouldbemaintainedandprotectedfromadverseactivity.Despitetheirrecognizedhighvalue,anestimated93to98%ofriparianareasinCaliforniahavebeenlostordegraded(Katibah1984,Dawdy1989).Rural and urban development can encroach on the riparian area and may result in vegetationremovalandbankarmoring.Decreasedriparianareasandincreasedimpervioussurfacesresultindecreasedwater infiltration and increasedwater delivery directly to the stream channel duringstormevents.Furthermore,withreducedwaterfiltrationservices,waterwaysreceivehigherloadsofsediment,nutrients,andotherpollutants.
Multiplefactorsinfluencetheeffectivenessoftheriparianarea’sabilitytoprovideallfunctions(e.g., stabilize banks, regulate water temperatures, etc.). Factors include but are not limited to:vegetativecomposition,soiltype,continuityalongthestream,streamsize,hillslope,anduseoftheadjacentland(Dillahaetal.1987,Castelleetal.1994,Desbonnetetal.1994,Ligonetal.1999,Wenger1999, Broadmeadow and Nisbet 2004, CDFW 2014). Therefore, it is important to consider site-specificfeatureswhenevaluatingariparianarea.Moderatetowelldrainedsoilshavetheabilitytopercolatesurfaceflowthatenterstheriparianzonequickly,thuspromotingsedimentremovalandgroundwater recharge (Desbonnet et al. 1994). Along with the width of the riparian area, thelongitudinalcontinuityorfragmentationofariparianareagreatlyinfluencesthequantityofbenefitsprovidedtoinstreamconditions.Ingeneral,alargerbufferisdesirableforahighfunctioningandvaluablestreamorwetlandwithhabitatforspeciesofconcerncomparedtoastreamwithlowhabitatvalue(CDFW2014).Additionally,alargerbufferisdesirableforastreamorwetlandwithintenseadjacentlandusecomparedtooneadjacenttoarelativelyundevelopedarea.Furthermore,riparianzonesshouldbewiderwhenlocatedwheresteeperhillslopesarepresent(Nieswandetal.1990,Beltetal.1992,BlinnandKilgore2001).
Thevegetativecompositiongreatlyinfluencestheecosystemservicesfortheriparianarea.Forexample,grassfilterstripsprovideeffectivesedimentfiltration,buttheycannotprovidelargewoodrecruitment,bankstability,andshadingthatforestedareasoffer.Therefore,grassyfilterstripsarebestusedincombinationwithaforestedriparianzone.Fullyeffectiveriparianzoneshavediverseplantassemblages,arecontinuousthroughoutthewatershed,andareofsufficientwidthtosupportandmaintaindynamicriparianandchannelformingprocesses.IncoastalnorthernCalifornia,theriparian zone is typically characterized by willow (Salix spp.), cottonwoods (Populus spp.), alder(Alnus viridix), Bay laurel (Laurus nobilis), Coast redwoods (Sequoia sempervirens), Sitka spruce(Piceasitchensis),salmonberry(Rubusspectabilis),bigleafmaple(Acermacrophyllum),andtypicalwetland plants such as rushes (Juncaceae spp.) and sedges (Cyperaceae spp.). These riparianvegetationassemblagesarelistedasrareandthreatenedbytheCNDDB(2017).
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Nosinglebufferwidthhasbeendeterminedtomaintainallfunctionsofariparianareaunderallcircumstances. However, a review of science, technical guidance, and policies can help guidedecisionsandaidinimplementationofeffectivelandscape-scaleriparianrestorationplan.Awiderangeofrecommendedvegetativewidthsandcompositionarefoundinthescientificliteraturebasedon the desiredmanagement objectives of the riparian area and the attributes of thewatershed.Overall,studiesshowthatnarrowbuffers(<100ft)areconsiderablylesseffectivethanwiderbuffersinminimizingthelong-termeffectsadjacentdevelopmenthaveontheaquaticenvironment(Ermanetal.1977,Castelleetal.1992,Brosofskeetal.1997,Mooreetal.2005).
BankStabilizationBankerosion isanatural streamprocess andde-vegetatedbanksaremore susceptible to the
erosivepowerofwater thanthose containing complex vegetation.During a49-year studyof theSacramentoRiver,Michelietal.(2004)foundthatstreambanksadjacenttoagriculturewere80to150%more erodible than stream banks with riparian forest floodplains. The above and belowground growth of riparian vegetation both aid inbank stabilization. Liquori and Jackson (2001)found riparian zones having complex understory vegetation were more effective at erosionpreventionthatthoseonlyformedbydensematureforestslackingunderstoryvegetation.Therootsofmaturetreesarevitaltobankstabilityandinhighlyincisedstreams,wherethechannellevelisbelowtherootingdepthofthetrees,riparianvegetationislikelytobelesseffectiveatmaintainingstreambankstability(Skidmoreetal.2009).Whilenarrowriparianareasmayeffectivelystabilizesomestreambanks,literaturerecommendswidthsrangingfrom33-196fttostabilizebanks(CulpandDavis1983,Ermanetal.1977).Furthermore,astructurallydiverseriparianzonecontaininggrassesandherbaceousmaterialswithshallowrootscombinedwith treeswithdeeperrootscanpreventbothtopsoilerosionandmasswasting(LiquoriandJackson2001,Michelietal.2004).
aquaticenvironment.Watertemperatureimpactsdevelopment,migration,andgrowthofsalmonidsandotheraquaticspecies.Thenaturalabilityoftheriparianzonetoregulatestreamtemperaturevariesbasedonriparianwidth,streamsize,vegetationtype,hillslope,aspect,andlocalclimate(Beltet al. 1992, Osborne and Kovacic 1993). A study comparing stream temperatures adjacent toagriculturallandwithoutriparianvegetationtostreamtemperaturesadjacenttoahardwoodforestfoundthatintheagriculturalstream,weeklymaximumtemperatureswere9°Fto22.5°Fhigherandminimumtemperatureswere7°Fcoolerthantheforestedstream(Green1950inKarrandSchlosser1977).Brosofskeetal.(1997)foundthatabufferof147-ftminimumisneededtomaintainanaturalmicroclimatealongstreamsinconiferousforests.ThemajorityoftheSmithRiverbasinhaswatertemperaturewithinthetolerablerangeforsalmonidsthroughouttheyear,particularlyinthewintermonths.However,areasofthemainstemhaveexceeded22°Cduringthesummermonths(Garwoodet al 2014, Parish and Garwood 2015, Parish 2016), a temperature considered to be above thetoleranceofjuvenilecohosalmon(Welshetal.2001).
PollutantFilteringVegetated riparian buffers are a cost-effective best management practice for agricultural
production for regulating the flow ofwater, sediment, nutrients, and pesticides entering stream
22
channels (USDA1998and2000).Sedimentscanenter thestreamchannel througherosionofthestreambanks,roadrunoff,landslides,orthroughoverlandflow.Theinputofexcessfinesedimentsinto a stream channel reduces habitat quality for fish and macroinvertebrates species (Wenger1999).Theeffectivenessofsedimentfiltrationbytheriparianzonedependsontheripariandensityandcomposition,overlandflowvolume,hillslope,widthoftheprotectedzone,andsedimentparticlesize(OsborneandKovacic1993).Researchhasfoundthatlargerparticlestendtosettleoutwithinthefirst10-20ftoftheriparianzone,butfinerparticlesthattendtodegradesalmonidhabitat,suchassiltandclay,needalargerriparianzonerangingfrom50-400ftforsignificantretention(Wenger1999,Parkyn2004).Whilesedimentretentioninriparianzoneshavingagrassriparianareaassmallas13ftcantrapupto100%ofsedimentunderspecificconditions(2%hillslopeoverfinesandyloamsoil),a98ftgrassriparianzonecanretainlessthan30%ofsedimentoversiltyclayloamsoilona10% hillslope (Dosskey et al. 2008). These studies highlight the width and composition of theriparianareaneededtoeffectivelyfiltersedimentishighlydependentonbothslopeandsoiltype.
Nitrogenandphosphorus arenutrients commonly found in fertilizer and livestockwaste andenterwaterways throughgroundwater floworoverland flow.The additionof thesenutrients toaquaticecosystemscanleadtopoorwaterqualityconditionsincludingreduceddissolvedoxygenrates,increasedpH,andeutrophication(Mayeretal.2005).Nitrogenremovalintheriparianzoneisrecognized as one of the most cost-effective means to reduce nitrogen delivery to streams inintensively developed watersheds (Hill 1996). The rate of nitrogen removal from surface andgroundwaterflowisextremelyvariabledependingonlocalconditionsincludingsoilcomposition,surfaceversussubsurfaceflow,riparianzonewidth,andripariancomposition(Mayeretal.2005).Nitrateretentionfromsurfacerunoffhasbeenshowntoberelatedtoriparianzonewidth,where50%,75%,and90%surfacenitrateretentionwasachievedatwidthsof110ft,389ft,and815ftrespectively (Mayer et al. 2005). Multiple studies have shown thatmulti-species riparian zonesprovide the best protections for streams against agricultural impacts (Haycock and Pinay 1993,Schultzetal.1995,Mayeretal.2005)andcanhaveinfiltrationratesasmuchasfivetimesashighastheadjacentagriculturalland(Bharatietal.2002).Mayeratal.(2005)concludedthatriparianzonesover98ftwidewouldbeexpectedtoretainnutrientsconsistentlywellacrossdifferentsites.USDA’s(1997)bestmanagementpracticerecommendsagrassyareaoutsideofaforestedzonetohelpslowanddistributesurfaceflowevenlytoaidininfiltrationandallowforestedriparianzonestomaximallyfilternutrients(Figure4).
Pesticidesandherbicides can enter riversandstreams throughpesticidedrift (i.e., carriedbywinds), overland flow (i.e., found in surface water or bound to organic matter and sediments),unintendedspills,orthroughgroundwater(i.e.,percolatedthroughthesoilstructure).Theriparianzonewidthnecessarytopreventpesticideexposuretoawatercourseisdependentonthepesticideandvariablessuchasclimate,hillslope,depthtowatertable,andripariansoilcomposition.Athick,multi-species riparian zone of adequate width can ameliorate the effects of pesticide drift andoverlandpollution,butpesticidesaredifficulttoremoveoncetheyhaveenteredthegroundwater.AccordingtoHewitt(2001),tallriparianzonesapproximately65ftwidecanreducepesticidedriftupto90%downwindofsprayareas,dependingonthesizeandspeciesofvegetation.Studiessuggestthatmulti-layeredcomplexriparianbuffersareneededtoprovidelong-termsediment,nutrient,andpesticide filtration capabilities (USDA 1998, Parkyn 2004, Mayer et al. 2005). While no Total
WoodRecruitmentBankerosionandchannelmigrationareimportantprocessesinrecruitinglargewoodydebris(LWD)intotheactivestreamchannel.LWDisacentralfeatureofstreamchannelsandplaysasignificantrole in geomorphic functions such as directing stream flows to shape the channel form whileinfluencing sediment storage, transport, anddeposition rates (Naimanetal.2002). Largewoodydebris create deep pools, velocity refuge, shade, complex cover from predators, andmacroinvertebrateinputs,allofwhichareessentialforrearingsalmonids(Elliot1986,QuinnandRoni 2001, Opperman 2005). While restoration techniques can directly add LWD to streams,structureshavealimitedlifespanandgenerallypersistforlessthan20years(Ronietal.2002).Thus,LWD structure placements offer a viable, but only short-term, approach to stream restorationwithoutnaturalrecruitmentofthesefeaturesfromtheriparianzone.Naturalrecruitmentfromtheriparianzoneisvitaltolongtermmanagementandsustainabilityofnaturalstreamprocesses.LWDtendstooriginatewithinawidthequivalenttothemaximumtreeheightwithintheriparianzone,referredtoassitepotentialtreeheight(SPTH).Collieretal.(1995)recommendedariparianzonewidthofatleastoneSPTHtomaintaininputsofLWD,althoughtopreventtheentireriparianzonefromsuccumbingtowindthrowandriskdestabilizingtheentirebank,theysuggesteduptothreeSPTHfromthetopofbank.
FlowModerationForested riparian zones facilitate the exchange of surface and groundwater, which provide
storageanddrainageoffloodwaters,andreducestreamsidepropertydamage.Additionally,channelmigrationisanaturalprocessasastreamchannelshiftsalongitsfloodplain.Thewidthofthechannelmigration zone is related to factors such as watershed size, active channel width, slope, theunderlying geology,and surrounding soil type (MNRO1996,USDA1998).Riparian setbacks thatallowfloodwaterstooverflowontothefloodplainalsoplayanimportantroleinfloodprotection.Riparian vegetation slows the rate of flow over floodplains, allowing for greater infiltration andgroundwaterrecharge(Tabacchietal.2000).Subsurfacewaterinthefloodplainslowlypercolatesthroughthealluviumandrechargestheriverandstreams,maintainingahigherbaseflowandcoolerinstreamtemperaturesduringthedriermonths.Theriparianareaneedstoremaininexistanceasthe channel naturally expands ormigrates along the floodplain and should be consideredwhendetermininglong-termmanagementgoals.
amphibians, reptiles, and many plant species (CDFW 2014). Of the 63 bird taxa designated asCaliforniaSpeciesofSpecialConcern,38primarilyutilizewetlandorriparianhabitats(ShufordandGardli2008).All47amphibianspeciesfoundinthePacificNorthwestutilizestream-riparianhabitats(Olson et al. 2007). Many North American bat species forage near or directly over open water(Pierson1998).Morethan116sensitiveplantspeciesinNorthernCaliforniaarefoundinwetland
Concent rat ed flows are converted to dispersed f lows by
ater bars or preaders acilit at ing ground
contact and infilt rat ion.
ZONE2 ZONE! MANA GED FOREST UNDISTURBED STREAMBOTTOM
FOREST Filt rati on, deposi ti on, plant Maturin g tr ees Debris dams hold det ritu s for upt ake, anaero bic provide detritu s processing by aquat ic fauna and denit rifi cati on land oth er t o th e str eam an provide cover and coolin g shage for natu ral processes remove dhe lp maintain f ish and oth er st ream dwell ers. sedim ent and nut rients fro m lower water runoff and subsurface f lows. temperature vial
to fish habit at.
....... -..,...._
ZONE! ZONE2 ZONE3 UNDISTURBED MANA GED FOREST RUNOFF CONTROL PASTURE
FOREST ree removal is Per iod ic harvestin g is Controlled grazing at er ing enera llyno necessary in zone 2 to or hayin g can be acili t ies and
permitt ed in thi s remove nutri ent s permitted in Zone liv estock are zone. sequest ered in t ree stems 3 und er certain kept out of th e
and branches and to conditions. Riparian Zone maint ain nut rient upt ake unless as t hrough vi goro us tr ee prescrib ed .
rowth.
25
andriparianhabitats(CDFW2014).Fischeretal.(2000)concludedthatbuffersofatleast164-328ft are required tomaintain avian biodiversity. Olson et al. (2007) concluded that on headwaterstreamsariparianareaof131-492ftisneededtosupporttheterrestriallifehistoryofamphibians.
Riparian zones play a significant role in the aquatic food web through effects onmacroinvertebrates, which are important prey formultiple species of salmonids, bird, bats, andamphibians.Riparianvegetationinfluencesbenthicinvertebratepopulationsbycontrollinglightandnutrient inputs, limiting sedimentation, delivering and retaining organic matter, and providingimportant habitat and food sources. Research has concluded that a riparian zone over 98 ft issufficienttomaintainbenthicinvertebratepopulationabundanceanddiversity(Ermanetal.1977,DaviesandNelson1994).Basedonliteraturereview,CDFW(2014)concludedthatanundevelopedriparianhabitatbufferofatleast164ftisnecessarytomaintainviablehabitatformanyofCalifornia’sriparianandwetlanddependentpopulations.
RiparianBufferPolicies
Researchprovidesawiderangeofconclusionsregardinghowvariouswidthsoftheriparianareaareneededtoperformandmaintain itsvarious functionsandecosystemservices.Becauseof thevariability of factors influencing the numerous riparian functions, and the wide range ofrecommendations regarding thewidthof the riparian area, it is important to consider (the) sitespecificcontextandprojectspecificgoalswhendeterminingthedesiredwidthoftheriparianarea.Regional landuseplanning canbe an effective landscape scalemethod toprotect riparian areas(CDFW2014). InCalifornia’sCoastal Zone, developmentbuffers onstreams,wetlands,andotherenvironmentallysensitivehabitatareasaredeterminedbylocalcoastalplans(LCPs)(CDFW2014).ThemajorityofLCPsstatea100-ft(30m)bufferastheminimumstandard,andespeciallysensitivehabitatsmayrequirealargerbuffer(CaliforniaCoastalCommission2007).WhilenospecificriparianbufferwidthalongstreamsisidentifiedintheDelNorteCountyLCP,theDelNorteGeneralPlan(CDN2003) identifies a 100 ft buffer for wetlands. Section 1.E.21. states, “the primary tool to reduceimpactsaroundwetlandsbetweenthedevelopmentandtheedgeofthewetlandshallbeabufferofonehundred feet inwidth.”However, theGeneralPlan states that “TheCounty shall ensure thatriparianvegetationbemaintainedalongstreams,creeks,andsloughsandotherwatercoursesfortheirqualitiesaswildlifehabitat,streambufferzones,andbankstabilization”(CDN2003)butdoesnotstateabufferwidth.
TheForestService(USDA1998)favorsathree-zoneripariansystemthatincludesbothazoneofrapidly growing, frequently inundated trees (e.g., willows) followed by long-lived species thatcontributetoshadingandlargewoodydebrisrecruitmentaswellasprovidinglarge,denserootmatsthatholdthestreambankstogether.Zone1isadenselyforestedzoneadjacenttothestreamchannelthat provides bank stability, a shade canopy, and habitat for aquatic organisms. Zone 2 extendsupslopeofzone1andiscomposedofshrubsandtrees.;Zone2’sprimarypurposeisto“remove,transform,orstorenutrients,sedimentandotherpollutants.”Zone3,locatedupslopeofzone2,iscomposedofstiff,herbaceousmaterials thatslowsurface flowtoallowforwater infiltrationandnutrientabsorption.Altogether,thesethreezoneseffectivelyminimizetheimpactsofsurroundinglanduseandbenefitthelocalfloraandfauna.
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In addition to Zone 3, the Forest Service recommends a thick grassy buffer that breaks upconcentrated flow to settle out some of the sediment by overland flow. The NRCS ConservationPracticeStandardriparianforestbufferinCalifornia(NRCSCA:Code391August2006)recommendsaforestedriparianzone100ftwideor30%ofthefloodplainwidth,butnolessthan35ftfromthetop of bank to reduce sediment, nutrients, and pesticides in surface and subsurface runoff. Thistypicallyequals3-5maturetreeswideoneachsideofthestream(USDA1998).USDA(1998)furtherrecommendsextendingthewidthbyaddingavegetativefilterstripadjacenttocropland,sparselyvegetated,orhighlyerosiveareas(Figure4).
RiparianBufferMethods
TwomethodswereusedtodeterminewhereriparianareashavethepotentialtoberestoredorprotectedacrosstheSmithRiverPlain.First,theedgeofthestreamwasidentifiedanddigitizedbasedon2016NAIPimagery(USDA2016)and2010-11NOAALightDetectionandRanging(LiDAR)datausingeditingtoolsinArcMap10.3.1(ESRI).ESRIspatialanalystbuffertoolwasemployedtocreatethreelayersofvariouswidths:1)35ft,theminimumwidthofbufferedfencingneededforCDFWFisheriesRestorationGrantsProgramandNRCSfunding;2)100ft,thebufferwidthrecommendedin the Del Norte General Plan for wetlands; and 3) 164 ft, based on the literature review andsubsequentrecommendationofCDFW(2014).Second,theriparianvegetationvisibleinthe2016NAIP imagerywasdigitized.The threebuffer layerswereoverlainon the2016NAIP image anddigitizedriparianarealayertoidentifylocationswhereriparianvegetationislackingandhasthepotential tobe improved. Finally, areaswithhigh conservationvaluewere identifiedby locatingpatcheswithriparianvegetationthatextendsbeyondthe164-footbuffer.TheSmithRiverHistoricAtlas(Lairdetal.2014)wasusedtocrossreferencehistoricandcurrentconditions,theidentifiedareaanddeterminetheapproximateageofthestand.Olderlargeriparianareaswereconsideredtohavehighconservationvaluetoensuretheseareascontinuetoprovidelongtermecosystemservices.Theresultinglistofpotentialriparianprojectswasreviewedwithlandowners,theRCD,andCDFWstafftoensureaccuracyandcompleteness.Thesepotentialriparianprojectsincludeallareaswhereriparian habitat extended beyond the 164 feet buffer andwhere native riparian vegetationwaslackingwithinthe35footbuffer.
InvasivePlantsInvasive plant species can causemultiple negative impacts to streamsand overall ecosystem
health and function, aswell as reducehabitat for fish andwildlife. Particular speciesof concernincludereedcanarygrass(Phalarisarundinacea),yellowflagiris(Irispseudacorus),andeucalyptus(Euclyptusobliqua).
ChannelComplexityStream channelization and bank armoring alter a streams natural hydrologic processes and
capacitytotransportwaterandsediment.Constructionofdikesandleveestypicallyresultinreducedchannelwidthandfloodplainconnectionincreasingstreamvelocity,sedimenttransport,andfloodfrequency(Bukaveckas2007).ChannelizationofRowdyCreekhasledtoincreasedstreamvelocitiesandsedimenttransport(GHD2015).Bankarmoringreducesnaturalchannelmigrationandbankerosionprocesses(MNRO1994).Consequently,thesesstreammodificationsreducehabitatquality(MNRO1994),preyavailability,andjuvenilesalmonidsurvival(QuinnandPeterson1996,Sommeret al. 2005). Furthermore, the disconnecting the surround landscape from the stream networkreduceswatersabilitytoreenterthestreamandincreasesthelikelihoodoffishstranding(Sommeretal.2005).Channelizedstreamsalsoreduceconnectiontoriparianforestsandwetlandsreducingastream’snaturalnutrientfiltrationcapabilities(Kuenzleretal.1977,MNRO1994).
ChannelComplexityMethods
Channelcomplexityprojectsweredeterminedbyevaluatinghistoricandcurrentstreamchannelalignment and active channel width. Restoration of areaswhere historic channel and landscapemodificationshavesimplifiedthechannel(i.e.straightenedchannels),reducedstreamandfloodplainconnection (i.e. levee and dike construction) and armored banks (i.e., rip rap installation) wereincludedaspotentialprojects.Streamchannelandhabitatconditiondatawasusedtoidentifyandevaluatepotentialprojectswhereavailable.
Additionally, NOAA 2010 Coastal LiDARwas used to identify low elevation areas adjacent tostreamchannelswithpotentialincreasedcapacity,toaccommodateflowandreducefloodingwhilealso enhancing off-channel habitat, minimizing fish stranding, and improving drainage of thesurrounding landscape.Historic imagescombinedwith lowelevationareaswereused to identifylocationsofpotentialoff-channelorwetlandhabitatenhancementareasacrosstheplanningarea.Lowelevationareasconnectedoradjacenttostreamchannelswereidentifiedaspotentialprojects.
Sea-levelispredictedtorise1.5feetinCrescentCityby2100,basedonthebaselineconditionsin2000, themedianprojection(i.e.,50%probabilitysea-level risewillmeetorexceedanelevationchange) under high greenhouse gas (GHG) emissions (OPC 2017). However, uncertainties forpredictingfutureconditionsrequirescientificstudiestoreportarangeofprojectedsea-levelrise(SLR)andtimeframes.BasedonuncertaintiesinfutureGHGemissions,theOceanProtectionCouncil(2017)reportsarangeof0.1ft–9.3ftby2100forCrescentCity.Selectingasea-levelrisescenariodependsonmultiplefactorsincludingprojectlocation,projectgoals,projectlifespan,andimpactsofsea-levelrisetotheprojectarea.
Toaccount forpotentialSLRscenarios,variousstepsshouldbe takentoevaluate thepossibleconsequencesandrisksofrestorationacrosstheSmithRiverPlain.TheOPC(2017)recommendsadecisionframeworkincludingfivesteps:1)usethenearesttidegauge;2)considerprojectlifespan;3)identifyarangeofSLRprojections;4)evaluatepotentialimpactsandcapacityacrosstherangeofSLR and emission scenarios; and5) select SLR projects based on risk aversion. These steps areconstantwithOPC’srecommendationofaprecautionaryapproachinthefaceofcomplexchallenges,scientificuncertaintyandclimatechange.
Coastalwetlandsandriparianareasprovide importantecosystemservices in the faceof largestormeventsandrisingsealevelsbyprovidingincreasedcapacitytoaccommodateflowandreduceflooding.AlargebodyofscientificliteraturewarnscurrentthreatstowetlandandriparianresourceswillincreaseduetoclimatechangeandSLR.Enhancedwetlandsandriparianareasincreasecoastalhabitatsabilitytoadaptandincreaseresiliencetochangingenvironmentalconditions(OPC2017).
Sea-levelRiseandInundationMethods
TheNOAAOfficeforCoastalManagementhasavarietyofDigitalCoasttoolstohelpcommunitiesaddresscoastalissues.Onesuchtool,SeaLevelRiseMappingTool,providesawaytoidentifyareaspotentially impactedbyup to6ft of SLR (NOAA2018b).This toolwasused tomapand identifyinundationscenariosandtheiroverlapwiththeplanningarea.
staff fromCDFW,NOAA,DelNorteRCDboard, and theTolowaDee-ni’NationNaturalResourcesProgramtodevelopandrefinequestionsthatwouldevaluateprogramattributeslike:thebiologicalandecologicalresources,theintegrityandrisk,andtheoptimismandpotentialforprotectionandrestorationof each identifiedproject (Bradbury et al. 1995).The criteria followsa “score sheet”approachtocaptureinputsforbenefitsandimpactsofprojects(Beechieetal.2008).
backwater habitat enhancement. Projects with the highest scores have the highest priority. Inassigningarankingvalue,respondentstookintoconsiderationthequantityofhabitatthatwouldbeprotected, improved, orbecomeaccessiblebasedon theproject scope and location. Scoreswereassigned using available information on biological resources, salmonid distributions, habitatconditionandlandownerinterest.Toaidinscoringdefinitionsweredevelopedforthescores1-5toallow reviewers to evaluate and score all identified projects uniformly (see below). The scoredefinitionsservedasguidelinesratherthanhardrules.
Natural resource and restoration specialists from NMFS, CDFW, and Smith River Allianceevaluatedandscoredallidentifiedprojectsusingquestions1-4.Thesefourquestionsrelatetothebiological impacts and benefits of an identified project. These scores were then averaged todeterminethescoreforthesequestionsforeachproject.Landowners’inputwasusedtodeterminethescoreforquestions5and6.Thesetwoquestionsrelatetothelandownerimpactsandinterestofan identified project.When landowners’ inputwas not available information on past or currentinterestandefforttoadvancerestorationorcollaboratewithmonitoringwasusedtodeterminetheprojectscoresforquestions5and6.Thedeterminedscoreforeachquestionwasthenmultipliedbythecorrespondingweightforeachquestion.
Inadditiontoindividualprojectscores,eachofthesixquestionswasevaluatedbyreviewerstoformulatetheweighteachanswerwouldbegiventothetabulatedrankings.Reviewersassignedaweight of 1-10 to each of the six questions, with the higher weight providing a percentage ofimportance.StakeholdersfromNMFS,CDFW,DelNorteRCDboard,andtheTolowaDee-ni’NationNatural Resources staff provided input on theweight to be given (relative value) of each of thecriteria.The informationwasused tocalculate theaverageweight foreachquestion.Asaresult,question#4,whichassessesaprojectsabilitytoaddressthecauseofhabitatdegradation,hasthehighest-ranking priority and question #5, a which assesses a project’s impacts to future landmaintenanceneedsandcosts,hasthelowestrankingpriority(Table3).
Similar to other restoration planning efforts, the prioritization scores and resulting projectrankingarenotintendedtoasthefinaljudgementregardingorderofimplementationforprotectionandrestorationdecisions(Bradburyetal.1995,VoightandWaldvogel2002,Lang2005).Landownerinterest,professional judgment,opportunitiescreatedbyscheduledmaintenanceorconstruction,andrestorationemphasisinaparticularwatershedbymultipleagenciesorstakeholdersshouldbefactoredintoimplementationdecisions.Thus,theseprioritizationrankingsprovideanopportunitytodiscussthebenefitsandopportunitiesthatdifferentprojectsofferforimprovingfishhabitatandstreamfunctionbutnotnecessarilyamandateforrestorationactions.Notwithstanding,projectsthatreceivedhighscoresarelikelytohavethemostbenefittosalmonidpopulationrecovery.
Table3.TheweightsprovidedbytheNationalMarineFisheriesService(NMFS),CaliforniaDepartmentofFishandWildlife (CDFW), Del Norte Resource Conservation District (RCD), and Tolowa Dee-ni’ Nation (TDN)averagedandusedintheprojectscoringprocess.
Ranking Criteria NMFS CDFW RCD TDN Average weight Rank
Current Biological and Ecological Resources
1 What is the level of immediate benefit of the project? 10 6.5 5 9.8 7.825 3
2 Besides benefiting salmonids are other species or ecosystem needs met by the project?
5 7 6 8.7 6.675 5
3 What is the magnitude of benefit for anadromous species? 10 10 7 6.6 8.40 2
Integrity and Risk
4 Does the project restore natural channel function and directly address a cause of habitat degradation?
8.5 10 8 7.4 8.475 1
Optimism and Potential for protection and restoration
5 Does the project minimize future land maintenance needs and costs? 3 6.5 10 1.8 5.325 6
6 Does the project have landowner support? 5 7 10 7.6 7.40 4
1= Improvesaminimalamountof thesub-basin is impacted(<10%)andonlyone lifestagebenefits.2=Improves10-50%ofthesub-basinandonlyonelifestagebenefits.3=Improves10-50%ofthesub-basinandalllifestagesbenefit.4=Improvesatleast50%ofthesub-basinandonlyonelifestagebenefits.5=Improvesatleast50%ofthesub-basinandalllifestagesbenefit.
IntegrityandRisk
4. Doestheprojectrestorenaturalchannelfunction?Consideriftheprojectwilldirectlyaddresscauses of habitat degradation. For example, does the project reduce sources of sediment fromnegatively impacting the channel or onlyremove the sediment currently in the channel.Will theprojecthaveshort-term(<5years)orlong-term(>5years)benefits.Doestheprojectreducethelikelihood of invasive plant species from thriving in the stream and riparian corridor or willcontinuedrestorationeffortsberequired. Ifaprojectprotectspristinehabitat it shouldrank thehighestpossibleasitwilldirectlypreventfuturehabitatdegradation.
1 = Long-term maintenance costs or negative impacts will be increased by projectimplementation(i.e.,costtolandowner).2=Long-termmaintenancecostsandnegativeimpactswillnotbealtered(i.e.,nobenefit/changetolandowner).3=Negativeimpactssuchasfloodingwillbereducedbutlong-termmaintenancecostswillnotbeimpacted.4=Maintenancecostswillbereducedbutnoreductioninnegativelandimpacts.5=Projectwillresultinreducedfuturemaintenancecostsandnegativeimpactsforlandowner.
6. Does the project have local landowner support? Consider the landowners interest in theprojectandiftheprojectwillsupportthelocalcultureandcustomsofthecurrentlanduseandlandmanagementgoals.
ResultsThisplanning effort identifiedand ranked137potentialprojectsacross the SmithRiverPlain
(Figure5).Theplanningareaissegmentedintoeightsub-basinsandthenumberofprojectsbysub-basin varies relative to the amountof anadromous streammiles (Table4, Figure5,AppendixA,AppendixC).Thenumberofprojectspersub-basinrangesfrom16to34.Notallsub-basinshaveprojects of all project types(Table4).Theprojectshavebeengrouped into fivedifferentprojecttypes. Thenumberofprojectsbytypeare:29riparian,33channelcomplexity,63fishpassage,8invasiveplantremoval,and4waterquality/quantityprojects.
Basedontherankingcriteria,channelcomplexityandpassageprojectsconsistentlyrankedhigherthantheotherthreeprojecttypes.Generally,thesehigherrankedprojectshaveamoreimmediatebenefittosalmonidsormoredirectlyaddressthecausesofchannelandhabitatdegradationthantheotherthreeprojecttypes(AppendixA).Moreover,thefurthestdownstreamprojectsgenerallyrankhigher than those upstream because the upstream projects impact a smaller quantity of habitat.Restorationpractitionerstypicallyfollowtheprogressionofworkinginadownstreamtoupstreamfashionsothatfishcanaccessnewlyavailable/restoredhabitat.
Overall,landownersareinterestedinlearningmoreaboutopportunitiestomoveprojectsforwardonlandtheyown.Interestishighestwhereprojectbenefitsbothnaturalresourcesandallowsforongoing operation of their property. A number ofprojects identified historic and recurring landmanagementissuesforlandowners(i.e.,flooding,failingculverts,reedcanarygrassmanagement).
Additionally, thereareeightbasinwiderecommendationsbasedonidentificationofrecurringprojectneedsanddata shortfalls,where further researchormonitoringwould informadditionalrestorationgoals.
to assess fish passage and listed in the California Department of Fish and Wildlife’s PassageAssessmentDatabase(PAD)(CDFW2018).Basedonfieldsurveysandlandownerfeedback,thereare two tide gates, 16 bridges, seven fords, 47 culverts, three concrete skirts/channel spanninginfrastructures, and three crossings of unknown type in the planning area. With landowner’spermission, 28 crossings were surveyed to assess fish passage. Using FishXing, two of the 28crossingswere classified as total barriers to all fish life stages and 15were identified aspartialbarriers (Appendix D Appendix C). Based on information provided by landowners and pastobservations,webelieve there are an additionalnineteen crossings that arepartial fishbarriers(AppendixD).Allofthesecrossingswereincludedandrankedaspotentialprojects.Additionally,crossingspreviouslysurveyedandidentifiedasbarriersinthePADwereincludedasprojects.
Culverts not identified as fish barriers but determined to be undersized and unable toaccommodate the 100-year flow were also included and ranked as two potential projects.Additionally,due to theirpotential impacts tonatural hydrologicprocesses and sediment inputs,bridgesandfordsshowntoconstrictorimpacttheactivechannelwereincludedaspotentialprojectsregardless of their passage status. However, some fords and bridges are classified as channelcomplexity projects based on surrounding channels lacking complexity. Last, four surfacewaterdiversionswereassessedandthreewereincludedaspotentialprojectsbasedontheirneedforfishscreening improvements. Diversions are considered passage projects consistentwith other localsalmonidrecoveryplans(CDFW2004a,NOAA2014).
Combinedbarriers, undersized crossings, anddiversions resulted in63 identified and rankedpassageprojectsacrosstheplanningarea(Table4).Allsub-basinshadapotentialpassageprojectlocatedonatleastonestream.Thedownstreammostpassageconcernrankedhighestoneachstreamthat had an identified potential passage project (Appendix A). The locations mapped for theseprojectsrepresentthelocationsofthecrossings(Figure5,AppendixC,AppendixD).
andwidthofriparianvegetationfromtheedgeofthestreamchannel (Table4).Locationswherenativeriparianforestispresentatleast164feetawayfromtheedgeoftheactivechannelresultedin11potentialprojectstoprotectorconservetheseareas.Additionally,anyriparianzoneshouldbeprotectedwhen possibledue to themultitude of ecosystem services provided by this vegetativebufferbetweentheterrestrialandaquaticenvironments.Locationswherenativeriparianvegetationislackingthroughoutthe35-footbufferarearesultedin18potentialprojectstoenhanceriparianvegetation.Additionally,10of thesesites lack fencingandcattlecanaccess thestream,with twolocationsincludingfords.Invasivevegetation,includingreedcanarygrassandHimalayanblackberry,commonly dominate the potential project locations where streamside vegetation lacks nativeriparianvegetation.The100-footbufferwasnotusedtoidentifyanyprojects.Ratherthisservedasatooltoshowlandownersthepotentialareaimpactedbya100-footriparianbuffer.Thelocationsfortheseprojectsrepresentthegeneralareaandarenotexactlocationsasthedistancealongthe
processesandbiodiversity.Onlylocationswithreedcanarygrass,yellowflagiris,andeucalyptuswereincludedaspotentialprojectareas.Reedcanarygrassistheprimaryinvasiveplantspeciesofconcernandwasincludedinsixofthepotential invasiveplantprojects.ReedcanarygrassaffectsportionsofallstreamsintheplanningareaexceptRowdy,Dominie,andStotenburgCreeks(Table4). Additionally, all projects with yellow flag iris overlapped with reed canary grass presence.Eucalyptusisrareintheplanningarea,onlypresentintheMorrisonandRowdyCreeksub-basins,andresultedintwoidentifiedpotentialprojects.Notwithstanding,theselocationscontaineucalyptusdominatedforeststandsthatareexpandingandoutcompetingnativevegetation.Thelocationsfortheseprojectsrepresentthegeneralareaandarenotexactlocationsasthedistancealongthestreampotentially protected or enhanced varies and cannot be shown by a single location (Figure 5,AppendixC).
evaluationofhistoricchannelconditionandavailabledataonhabitatandchannelcondition(Table4).Of these33projects, eight are focusedon enhancingbackwater/off channelhabitat, eight arefocusedonenhancingfloodplainconnectivity,and17focusedonenhancingchannelandinstreamstructure. Many of these projects are adjacent to riparian enhancement projects. Uponimplementation,pairingtheseprojectswouldbemostefficientandeffective.Thelocationsfortheseprojects represent the general area andarenot exact locationsas thedistance along the streampotentially protected or enhanced varies and cannot be shown by a single location (Figure 5,AppendixC).
touncertaintyinpredictionsandfutureconditions.However,basedonSealLevelRiseMappingTool,numerousidentifiedprojectswouldoverlapsea-levelriseof6feet(Figure6).Anevenlargerportionof the project area would be impacted if the predictions under high greenhouse gas emissionsconditionsof9.3feetsea-levelriseby2100areaccurate(OPC2017).Restorationactionscanbetakentoreducethepotentialnegativeimpactsofsea-levelrise.Forexample,restoringchannelcomplexityand floodplain connection are tools to increase resilience to sea-level rise. As is advised byOPC(2017),restorationprojectsshouldconsidersea-levelriseprojectsandevaluatepotentialimpactsacrossvariouspredictions.Thelifespanoftheprojectandaversionriskshouldalsobeconsideredwhenmakingrestorationdecisions.TheSeaLevelRiseMappingToolprovidedbytheNOAAOfficeforCoastalManagementprovidesatoolforplannerstoquicklyvisualizeinundationandelevationdata. This tool can be used to determine if projects are located in flood prone areaspotentiallythreatenedbycoastalfloodingorsealevelrise.
4).Whileoverallwaterqualityishigh,isolatedareaspotentiallyimpactingwaterqualityarepresentandcancontributetodecreasedwaterqualityoftheestuaryandcoastalplain.Examplesinclude:agricultural production; oldand failingseptic systems in andaround the townsofCrescentCity,Gasket,andSmithRiver;andtheRowdyCreekFishHatchery.
The 2010 Statewide integrated report determined that no sub-basin should be listed as animpairedwaterbodybyanypollutantevaluatedinsection303(d)undertheCaliforniaCleanWaterAct (CWB2016). This evaluation includes various pollutants such as nitrates,metals, pesticides,dissolvedoxygen,pH,temperature,andtotaldissolvedsolids.However,manyofthestreamsintheSmith River Plain are not included in this 2010 evaluation. Furthermore, possible sources ofcontaminationare typically isolatedandrestorationcouldmakesubstantialbenefits to thewaterquality.
RecentwaterqualitymonitoringfoundsomewaterqualitysamplestobeaboveEPAstandards(CWB2018,NOAA2018a).However,extremelylowconductivityandhardnessofthesourcewatersaddeduncertaintytosamplingresults(CWB2018).ThesefindingssuggestsomewatersoftheSmithRiverPlainwouldbenefitfromcontinuedwaterqualitymonitoringtoevaluatepollutantloadsandto determinewhere restoration actions or implementation of bestmanagement practices (BMP)wouldbenefitwaterqualityconditions.BaselinemonitoringisneededtodevelopamanagementplanandevaluatetheeffectivenessofBMPsandrestorationactions.
FurthersamplingwillhelptodeterminewaterqualitystandardsandTMDLlevels.Intheinterim,potential projectswith theuseBMPsof canminimize inputs frompointandnon-pointpollutionsources that reduce water quality. Additionally, flow paths have historically been altered toaccommodate land use needs. Thesemodifications could potentially be adjusted to increase thedurationofsurfaceflowsinintermittentanadromousstreamsforthepurposeofextendingthefishmigration period during the spring months. A hydrologic assessment in the Tillas Slough andMorrisonCreeksub-basinswouldhelpidentifyandrefinewheretheseopportunitiesexist.
Lastly,thehighestdensityofimpervioussurfacesislocatedaroundRowdyandDominieCreeksduetoruralandcommercialinfrastructure.Someofthisdevelopmentisimmediatelyadjacenttothestreamswithnofilterorriparianbufferareapresent.Theoldtimbermillsitecontainsatleast15acresof unused impervioussurfacewithin theRowdyCreek floodplain.This results in increasedrunoffandlossofoff-channelfloodplainhabitat.Incorporatinglowimpactdevelopmentpracticesaroundexistingandfutureinfrastructurecanincreasewaterqualityandquantity.
areeightbasin-wideprojectsthatdeservemention(AppendixA).Weidentifiedthesebasedondatashortfalls,potential threats from invasivespecies,andcommonchannelconditionsthatminimizenaturalfunctionofthestreamchannelsacrosstheplanningarea.Theseprojectswerenotprioritizedbutshouldbeconsideredwhenplanningduring futuredevelopment,monitoring,andrestorationprojects.
1. PreventthespreadandintroductionofinvasivespeciesbydevelopingspeciesspecificplanslikeaReedCanaryGrassManagementPlan.Preventingthespreadandintroductionofinvasivespecies is vital tomaintaining the resilience and health of the Smith River Plain streamecosystemsandnativespecies.Inparticular,thepresenceandspreadofreedcanarygrassresultsindecreasedchannelcapacity,increasedchannelaggradation,reducedwaterquality,andcompetitionwithnativevegetation.Reedcanarygrassisdifficulttoremoveandmanageand is present throughout most streams in the planning area. A management plan thatidentifies effective and efficient techniques to remove andmanage this invasive plant isneededtohelprestorenaturalstreamhealthandhydrologicfunction.
2. PrepareaBullFrogPreventionPlan.TheAmericanbullfrog(Lithobatescatesbeianus)isaninvasivenon-nativespeciesinCaliforniathatisapredatorandknowntocontributetothedeclineofnativeaquaticandterrestrialspecies,includingsalmonids.InthePacificNorthwestbullfrogtadpolestakeapproximatelytwoyearstometamorphose.Hence,theyrequireyear-roundpondedwatertosuccessfullyreproduce.WithintheSmithRiverbasinbullfrogshaveonlybeendetectedinRattlesnakeLakebutarelikelytobeinothersuitablelocationsnotyetdocumented.Theagriculturalwaterinfrastructure(i.e.,perennialponds)providepotentialhabitat for the expansion of the American bullfrog in the basin. A prevention plan thatincludes education and outreach will assist in early detection and rapid response if thespeciesspreadsintotheplanningarea.AcomprehensiveresponseisthebestwaytopreventthisspeciesfrombecomingestablishedontheSmithRiverPlain.
3. FloodplainandChannelStructure–Increasechannelcomplexity.Allsub-basinsintheplanningareahaveareaswithsimplifiedchannels.Restorationprojectplanningshouldincorporatepractices that restore processes that will restore natural stream and ecological functionshouldbeconsidered.Anyprojectalong thestreamsorriparianareasshould incorporatepractices that restoreprocesses thatwillmaintainnaturalstreamandecological functionwhenever possible. Consulting with natural resource specialists early and often duringproject developmentwill help incorporate a variety of ecological considerations therebyprovidingthemaximumbenefittotheecosystem.
Recent monitoring and planning efforts have provided a wealth of data on the aquaticenvironmentoftheSmithRiverPlain.Nevertheless,datagapsstillexistandwerecommendthreeareasinparticularwhereadditionaldataisneeded.
7. CollectLampreyDistributionData.Lampreyareananadromousspeciesthatreliesonhighwaterquality,andgiventheirlifehistory,accesstoqualityperennialstreamhabitatsacrossthe Smith River basin. Data is lacking on lamprey distribution and habitat availabilitythroughouttheSmithRiverbasin,particularlyintheSmithRiverPlain.Increasedknowledgeoflampreypresencewillaidininformingmanagementandrestorationactionsinthebasin.
8. EffectsofPinnipedandAvianPredationonsalmonids.Littleisknownregardingtheinterplaybetween salmonid habitats and predation effectsby pinnipedandavianpredators in thelower SmithRiver.Data allowing for the analysisof predator impacts in the estuary andcoastalplaincanaidininformingmanagementandrestorationtechniquestoprotectSmithRiversalmonidpopulations.
ImplementationRecommendationsThe purpose of this plan was to identify and prioritize potential projects along anadromous
streams that focus on restoring, protecting and enhancing natural stream function, long-termecosystemhealth,waterquality,salmonidrecovery,andbiodiversityacrosstheSmithRiverPlain.Byevaluatingthehistoricandcurrentconditionsoftheanadromousstreamsintheplanningareaweidentified 137 potential projects. There is no regulatory nexus mandating an implementationtimeline for the identified projects. Rather, the intent of the developed ranking criteria was toprioritizerestorationopportunitiesbasedontheirabilitytoenhancehabitatforanadromousspecies,whileconsideringpossiblemulti-benefitsofaprojectandlandownerfeedback.
Themajorityof thepotential conservation and restorationprojects identified in thisplan arelocatedonprivatelandandrequirevoluntarylandownerparticipationtoadvanceandimplementanyactions.Conservationandrestorationpractitionersshouldusethisplanasaguidetoworkwithlandownerstoidentifyandadvancealternativesthatarecompatiblewiththelandownerneedswhilealso meeting salmonid and natural resource improvement goals. This will require carefulconsideration fortheneedsof theworking landswhileevaluatingthecurrentanddesired futureconditionsoftheanadromouswaterways.
Thisreportmakesnorecommendationsonwhattechniquesshouldbeusedtoconstructorfundthe identified projects, however, best management practices should be used if they have beendevelopedfortherestorationtechnique.Furthermore,assessingthesurroundingprojectarea(i.e.,slope,soil,vegetation,landuse)willbeneededtodeterminerestorationtechniquesneededtoreachrestorationgoals.BasedontheSONCCcohosalmonrecoveryplan(NOAA2014)itisestimatedthatatotalof$136millionisneededtoconductrecoveryactionsthroughouttheSmithRiverbasintorestorethecohosalmonpopulation.BasedontheestimatedcostsoftherecoverytaskslocatedintheSmithRiverPlain(NOAA2014),approximately$20.5millionisneededtocompletetheidentifiedprojects in this plan. Due to this high cost, restoration opportunities created by scheduled
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maintenanceorconstructionshouldbeutilized toaddress identifiedprojectswheneverpossible.Effortsshouldfocusfirstonhighpriorityprojectsduetolimitedfundingandthestatusofthecohosalmonpopulation in thebasin.Moreover,manyprojects are located in closeproximity tootherpotentialprojectsandshouldbegroupedwhenpossibletoincreaseefficiencyandreducecosts.
This report also makes no recommendation on the timeline for which projects should beimplemented. Projected dates for developing and implementing restoration and monitoringmeasuresshouldincludeshort-term(upto3years)andlong-term(upto10years)goals.Creatingmilestones,phases,andstepsforactionwithlandownerswillhelptoidentifywhenmanagementandmaintenance opportunities exist to address identified projects. Collaborating with neighboringlandownersandstakeholderscanhelpforecastprogrammedmaintenancework(e.g.CalTrans,DelNorteCountyRoads).Acollaborativeeffortwillhelptomaximizefundingandresourceallocation.Whenadvancinganyproject,criteriashouldbedevelopedtoevaluateifrestorationgoalsaremetandincludemonitoringtoevaluateeffectivenessofrestorationefforts.
This planning element is part of a larger ongoing process that should be followed up withimplementation and re-evaluation as projects are completed and when physical and biologicalmonitoringprovidesfeedbacktoinformtheadaptivemanagementandnextstepsintheplanningprocess.Achievingecosystemresiliencyinaworkinglandscapewillbeachievedatthehighestlevelbyidentifyingamultitudeofresourcegoalsandneedsthatenhancetheecosystemandprovidebroadbenefitsratherthanworkingforasingleresourceconcern.Throughpartnershipengagementintheplanningandimplementationprocessresources,skillsandexpertiseprovidedbystakeholderswillinformandimprovetheprocess.
Ultimatelyimplementationoftheidentifiedprojectswillrequirelandownercooperationandwillbemosteffectivewhenconductedwithrestorationandnaturalresourceprofessionals.Education,outreach,andpartnershipamongallinterestedpartiesisessentialtomosteffectivelyandefficientlyreaching desired outcomes. Success of the plan requires continued short-term and long-termplanningbylandownersandstakeholdersthattogetherwilldevelopandimplementplanstorestore,protect,andenhancenaturalresourceswhileaccountingforsocialandeconomicneedsintheSmithRiverPlain.
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34 Ritmer Creek crossing #1 Ritmer Creek No Ford Green* Passable* Unknown NA 402271 4642834 2300 34 Ritmer Creek crossing #2 Ritmer Creek No Ford Green* Passable* Unknown NA 402365 4642933 2300 35 Ritmer Creek crossing #3 Ritmer Creek No Culvert (CMP x2) Grey* Partial* Unknown Velocity and Depth* 402403 4643079 2141
36 Ritmer Creek crossing #4 - Hwy 101 (PAD: 707135) Ritmer Creek Yes - PAD Arch Culvert (x2) Grey Partial Juvenile and
Resident Leap 402568 4643437 1739 37 Ritmer Creek crossing #5 Ritmer Creek No Ford Green* Passable* Unknown NA 402706 4643541 1545
38 Ritmer Creek crossing #6 - Ocean View Dr (PAD: 705875) Ritmer Creek Yes - PAD Culvert Grey Partial All Velocity and Depth 403180 4643938 883
40 Delilah crossing #1 Delilah Creek No Unknown Grey* Partial* Unknown Velocity and Depth* 402839 4642301 1883 41 Delilah crossing #2 Delilah Creek No Culvert (CMP) Grey* Partial* Unknown Velocity and Depth* 403156 4642272 1506 42 Delilah crossing #3 - Sarina Rd Delilah Creek No Culvert (Concrete) Unknown Partial* Unknown Velocity* 403366 4642406 1260 43 Delilah crossing #4 Delilah Creek No Culvert (CMP) Grey* Partial* Unknown Velocity* 403619 4642623 828 45 Delilah crossing #5 - Hwy 101 (north) Delilah Creek No Culvert (CMP) Unknown Unknown Unknown NA 403632 4643039 245 51 Tryon Creek crossing #2 Tryon Creek Yes Culvert (CMP) Green Partial Multiple Depth and Velocity 401845 4639120 9295 54 Tryon Creek crossing #3 - Silva Rd Tryon Creek Yes Bridge Green Passable None NA 401909 4638341 8477
55 Tryon Creek Trib #1 Tryon Creek Yes Culvert (plastic) Grey Partial Juvenile and
Resident Velocity and Depth 402937 4638171 380 56 Tryon Creek crossing #6 - Private Tryon Creek Yes Culvert Green Partial All Velocity and Depth 402829 4637756 6474 57 Tryon Creek crossing #8 - Mosely Rd Tryon Creek Yes Culvert (Concrete) Green Partial Resident Velocity 403773 4637130 5121 58 Tryon Creek crossing #10 - Private Tryon Creek Yes Culvert (Concrete Grey* Partial* Unknown Depth* 404463 4636465 3952 59 Tryon Creek crossing #11 - Private Tryon Creek Yes Ford Green Passable None NA 404592 4636411 3800 61 Tryon Creek crossing #13 - Private Tryon Creek Yes Culvert (x2) Grey* Partial* Unknown Depth* 405112 4636190 3228 62 Tryon Creek crossing #14 - Private Tryon Creek Yes Bridge Green Passable None NA 405346 4636138 2954 63 Tryon Creek crossing #15 - Hwy 101 (PAD: 712949) Tryon Creek Yes - PAD Culvert Grey Partial Multiple Depth 405465 4636068 2809
71
Project # Project Stream Surveyed Structure Type CDFW
Barrier Status
Life stages blocked FishXing Reason UTME UTMN
Habitat US (m)
65 Tryon Creek crossing #16 - Private Tryon Creek No Culvert (concrete) Grey* Partial* Unknown Velocity* 405584 4635948 2562 66 Tryon Creek crossing #17 - Private Tryon Creek No Culvert (CMP) Grey* Partial* Unknown Velocity* 405596 4635766 2365 67 Tryon Creek crossing #18 - Rellium Road Tryon Creek No Culvert (CMP) Grey* Partial* Unknown Velocity* 405622 4635365 1932 77 Rowdy Creek Fish Hatchery Weir (PAD: 721887) Rowdy Creek Yes - PAD Concrete skirt Grey Partial All Velocity and Leap 405152 4642416 23618 84 Dominie Creek Mouth alteration (PAD: 721903) Dominie Creek Yes - PAD Concrete skirt Grey Partial All Velocity and Leap 405148 4642415 3271
85 Dominie Creek RCFH water intake & fish ladder Dominie Creek No Water diversion and fish ladder Grey Partial* Juvenile Velocity 405094 4642519 3150
86 Dominie Creek - Hwy 101 (PAD: 707134) Dominie Creek Yes - PAD Box culvert (concrete) Grey Partial Multiple Leap and Depth 405059 4642588 3072 89 Morrison crossing #1 - Tidewater Road Morrison Creek Yes Culvert Grey* Partial* Unknown Velocity* 404088 4639791 8327 93 Morrison crossing #3 - Fred Haight Drive Morrison Creek Yes Culvert (CMP x3) Grey Partial Juvenile Velocity 404907 4639665 4906 94 Morrison crossing # 4 Morrison Creek Yes Bridge Green Passable None NA 404957 4639747 4802 96 Morrison crossing # 5 Morrison Creek Yes Bridge (Foot) Green Passable None NA 404977 4639787 4761 97 Morrison crossing # 6 Morrison Creek No Ford Green Passable None NA 405073 4639934 4571 98 Morrison crossing # 7 Morrison Creek No Bridge Green Passable None NA 405266 4639911 2201
100 Morrison crossing #8 - Hwy 101 (PAD: 707133) Morrison Creek Yes - PAD Box culvert (concrete) Grey Partial All Velocity and Depth 405737 4640390 1406 101 Morrison crossing #9 - Morrison Creek Rd Morrison Creek No Culvert (CMP) Grey* Partial* Unknown Unknown 405918 4640763 946
103 Morrison trib crossing #1 Morrison Unnamed tributary No Culvert Green Passable None NA 405279 4639837 2793
105 Morrison trib crossing #2 Morrison Unnamed tributary Yes Culvert (CMP) Red Total All Velocity and Leap 405522 4639755 2404
107 Morrison trib crossing #3 Morrison Unnamed tributary Yes Culvert (CMP) Grey Partial All Velocity and Depth 405581 4639662 1791
112 Mello Creek crossing #1 Mello Creek Yes Culvert (plastic) Grey Partial Juvenile and
Resident Velocity 404361 4639741 2874 113 Mello Creek crossing #2 Mello Creek Yes Culvert (plastic) Green Passable None NA 404520 4639578 2203 114 Mello Creek crossing #3 - Fred Haight Dr Mello Creek No Culvert (CMP) Unknown Unknown Unknown NA 404907 4639506 2174 117 Mello Creek crossing #4 Mello Creek No Culvert Unknown Unknown Unknown NA 405345 4639194 1515 118 Mello Creek crossing #5 Mello Creek No Culvert Unknown Unknown Unknown NA 405373 4639183 1470 119 Mello Creek crossing #6 - Hwy 101 (PAD: 712951) Mello Creek Yes - PAD Culvert (CMP) Unknown Unknown Unknown NA 405715 4639160 1115 121 Mello Creek crossing #7 Mello Creek No Unknown Unknown Unknown Unknown NA 405890 4638895 763
123 Stotenburg crossing #1 Stotenburg Creek Yes Culvert (CMP) Grey Partial All Velocity, Depth and
Leap 404895 4638013 2249
72
Project # Project Stream Surveyed Structure Type CDFW
Barrier Status
Life stages blocked FishXing Reason UTME UTMN
Habitat US (m)
124 Stotenburg crossing #2 Stotenburg Creek Yes Culvert (CMP) Grey Partial Juvenile and
Resident Velocity 404943 4637965 2177 125 Stotenburg crossing #3 Stotenburg Creek No Ford Green Passable None NA 405055 4637874 2030 126 Stotenburg crossing #4 - Cedar Lodge Lane Stotenburg Creek Yes Culvert (Plastic x4) Grey Passable NA NA 405290 4637704 1732 128 Stotenburg crossing #5 Stotenburg Creek Yes Culvert (CMP) Green Partial None Depth and Leap 405442 4637551 947
129 Stotenburg crossing #6 - Fred Haight Dr Stotenburg Creek Yes Culvert (CMP) Grey Partial All Velocity, Depth and
Leap 405485 4637598 887 131 Stotenburg crossing #7 - Hwy 101 (PAD: 712950) Stotenburg Creek Yes - PAD Culvert Grey Partial All Velocity and Depth 405696 4637897 419 132 Stotenburg Creek Trib #1 Stotenburg Trib No Culvert Unknown Unknown Unknown NA 405570 4637485 316 134 Stotenburg Creek Trib #2 - Fred Haight Drive Stotenburg Trib No Culvert Unknown Unknown Unknown NA 405589 4637513 283 136 Stotenburg Creek Trib #3 - Hwy 101 Stotenburg Trib No Culvert Unknown Unknown Unknown NA 405690 4637542 178 137 Stotenburg Creek Trib #4 - pond Stotenburg Trib No Unknown Unknown Unknown Unknown NA 405847 4637529 10 NA Tryon Creek crossing #1 - Pala Rd Tryon Creek No Bridge Green Passable None NA 400757 4640309 12422 NA Tryon Creek crossing #4 - Lower Lake Rd Tryon Creek Yes Bridge Green Passable None NA 402060 4638314 8312 NA Tryon Creek crossing #5 - Private Tryon Creek Yes Bridge Green Passable None NA 402303 4638317 8053 NA Tryon Creek crossing #7 - Private Tryon Creek Yes Bridge Green Passable None NA 403409 4637432 5643 NA Tryon Creek crossing #9 Tryon Creek No Bridge Green Passable None NA 404036 4636555 4408 NA Tryon Creek crossing #12 - Lake Earl Dr Tryon Creek No Bridge Green Passable None NA 404832 4636272 3506 NA Rowdy Creek - Fred Haight Drive Rowdy Creek No Bridge Green Passable None NA 404967 4641715 24955 NA Rowdy Creek - Hwy 101 Rowdy Creek No Bridge Green Passable None NA 405190 4642473 20858 NA Dominie Creek #4 Dominie Creek No Bridge Green Passable None NA 404950 4642926 2707 NA Dominie Creek #5 Dominie Creek No Bridge Green Passable None NA 405074 4643179 2425 NA Morrison crossing #2 - Cattle bridge Morrison Creek Yes Bridge Green Passable None NA 404524 4639721 5308
*Assessment determined by information provided from landowner on crossing type, size, and condition.