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A publication from
The Land Conservancy of San Luis Obispo County
Restoration
Field GuideA USER-FRIENDLY GUIDE FOR RESTORATION TECHNIQUES
IN RIPARIAN HABITATS.
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Contents
CONTENTS..........................................................................................................................................................i
BACKGROUND...................................................................................................................................................1
ABOUTTHEAUTHORS........................................................................................................................................2
ACKNOWLEDGMENTS........................................................................................................................................3
LITERATUREREVIEW..........................................................................................................................................3
PROJECTPLANNING...........................................................................................................................................7
WATERSHEDANALYSIS....................................................................................................................................................7
PROJECTPLANS&DESIGNS............................................................................................................................... ...............8
PROJECTPERMITS..........................................................................................................................................................9
PROJECTFINANCING............................................................................................................................... ......................10
LANDOWNERCOORDINATION............................................................................................................................... ..........11
CONTRACTING............................................................................................................................... ..............................12
THEFIRSTDAYFIELDMEETING&SAFETYPLANNING..........................................................................................................13
WORKINGWITHHEAVYEQUIPMENT............................................................................................................................... .14
WATERDIVERSIONS&WORKSITEISOLATION...................................................................................................16
WORKSITEISOLATION............................................................................................................................... ...................16
IsolationUsingStrawBales............................................................................................................................... ..17
IsolationUsingCofferDams............................................................................................................................... .17
MoreTipsonIsolations............................................................................................................................... ........19
STREAMDEWATERING..................................................................................................................................................19
FishRelocation.................................................................................................................................................... 19
StreamDewateringTechniques..........................................................................................................................22
BUILDINGHABITATSTRUCTURES......................................................................................................................28
ROCKSTRUCTURES............................................................................................................................... ........................28
ROOTWADS............................................................................................................................... ................................31
GRADIENTCONTROL.........................................................................................................................................33
STREAMBANKSTABILIZATION...........................................................................................................................34
TIPSFORBANKSTABILIZATIONPROJECTS..........................................................................................................................35
SLOPE&BANKTOESTABILIZATION............................................................................................................................... ...37
RockRiprap.........................................................................................................................................................37
RockToeProtection............................................................................................................................... .............37
BiologToeProtection............................................................................................................................... ...........38WillowFascineToeProtection............................................................................................................................38
THINGSTOAVOID........................................................................................................................................................39
UPPERBANKSTABILIZATION...........................................................................................................................................41
Brushlayering&BrushMattress.........................................................................................................................41
SoilWraps...........................................................................................................................................................42
REVEGETATIONPROJECTS&TECHNIQUES.........................................................................................................44
PROJECTPLANNING......................................................................................................................................................44
SITEPREPARATION.......................................................................................................................................................44
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ii
CHOOSINGPLANTS............................................................................................................................... ........................46
TipsforPlantPalettes.........................................................................................................................................46
PLANNINGFORIRRIGATION............................................................................................................................... .............47
PLANTINGMETHODS............................................................................................................................... .....................50
PROJECTMONITORING.....................................................................................................................................54
CONCLUSION....................................................................................................................................................55
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Background
Thisfieldguideforriparianrestorationtechniques,publishedJuly2010,isanoutgrowthofhabitat
restorationprojectsfundedbytheAvilaBeachTrusteeCouncil,apartnershipbetweentheCalifornia
DepartmentofFishandGame(CDFG)OfficeofSpillPreventionandResponse(OSPR)andtheU.S.Fish
andWildlifeService(USFWS).TheTrusteeCounciloversawmultiplerestorationprojectsassociatedwith
thesettlementwithUnocaloveranoilspillinAvilaBeachin1992.TheTrusteeCouncilretainedtheLandConservancyofSanLuisObispoCountytoassistintheplanningandimplementationofprojects
designedtorestoreorreplaceresourcesdamagedbythespill.Between1999and2008,projectswere
completedthataddressedmigrationbarriersforsteelhead,streambankstabilizationandrevegetation,
instreamhabitatforsteelhead,andwaterqualityenhancement.
Throughouttherestorationprojects,theLandConservancyreliedheavilyonpublishedguidesto
developimplementationstrategies.Thesepublishedresourcesprovidedextensiveinformation
regardinghowprojectsshouldlookwhenconstructed.However,theycontainedverylittleinformation
ofapracticalnaturerelatingtohowtheprojectsshouldbebuiltandwhatpotentialproblemscould
ariseduringconstruction.Projectdelayscausedbyaccidents,unforeseenproblems,andinsufficientmaterialsonsitemakeprojectsmorecostlyandcomplicatedthannecessary.Theymayalsocause
damagetohabitatsandinjurytopeople.Itwasonlythroughtheexperiencegainedinthefield,or
communicatedbyotherexperiencedrestorationmanagers,thatmethodsweredevelopedtoaddress
commonproblemsassociatedwithcommonprojecttypes.
ThepurposeofthisfieldguideistosharetheexperiencesoftheLandConservancystaffandother
restorationorganizationsgainedduringimplementationofrestorationprojectssofellowproject
coordinatorscanbetterplanconstructionprojects.Itisnotintendedtobeacomprehensiverestoration
manual,butratherauserfriendlyguidetospecificfieldrestorationtechniquesandtroublesavingtips.
Theconceptspresentedherearefieldtested,andwillhelpusersprepareforandsolvecommon
problemsthatmayariseduringaproject.Thisguidewillbeusefulforcomplexriparianrestoration
projects,includingdamagedriparianhabitatthatmayneedrestorationafteremergencyresponse
procedures,suchasoilspillcleanupinastream.
Theguideisintendedtobeusedasacompaniontootherauthoritativerestorationguides,andis
primarilygearedtowardagencypersonnelrespondingtoemergencysituationsinriparianareasandthe
nonprofitpartnersthatareoftenengagedinthefollowuprestorationwork.However,even
professionalrestorationspecialistsmaygleanvaluabletipsastheynavigatenewandchallenging
projects.Theguideassumesthatthereadershavesomeelementaryknowledgeofstreamhabitatsand
restorationtechniques.Thereferenceslistedintheliteraturereviewincludemorespecificdesign
informationthanwhatisdiscussedinthisguide.
Theprojectsuponwhichthesesuggestionsarebasedhaveprimarilybeeninthesouthcentralcoastarea
ofCalifornia(SanLuisObispoCounty),withsomeexperiencefromtheupperSacramentoRiver.The
habitatsonthesesiteshavesomebearingonthesolutionschosentoshare.Somelendthemselves
betterthanotherstotransferringtootherpartsofthestate.Readersareencouragedtoadaptsomeof
theserecommendationstotheirownareasratherthandependsolelyontheserecommendations.
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About the Authors
BrianStarkhasworkedthroughoutSanLuisObispoCountyonover30habitatrestorationand
watershedplanningprojectsinvolvingstakeholderoutreach,watershedenhancementplanning,
streambankstabilization,fishpassagebarriermodifications,revegetation,andwaterqualitymonitoring.
ManyoftheseprojectswerecompletedonbehalfoftheAvilaBeachTrusteeCouncil,apartnershipof
theCaliforniaDepartmentofFishandGame(CDFG)OfficeofSpillPreventionandResponse(OSPR)and
theU.S.FishandWildlifeService.HeistheauthoroftheFinalPlanforRestorationActionsWithinthe
SanLuisObispoCreekWatershed;UnocalOilSpill,AvilaBeach,1992,andmanagedtheimplementation
oftheprojectsdescribedintheplan.Hehasalsomanagedmultipleprojectsforotherfundingagencies
overthelast15years,includingprojectsassociatedwithanotheroilspillinAvilaBeach.Brianisalsothe
authoroftheSanLuisObispoCreekWatershedEnhancementPlanandtheSanLuisObispoCreek
InvasiveSpeciesManagementPlanforRiparianAreas,andcoordinatedtheSanLuisObispoCountyFish
PassageBarrierPriorityProjectfortheCaliforniaStateCoastalConservancy.
KailaDettmanmanagedseveralprojectsthataroseoutoftherestorationprogramthatwerenotinthe
originalrestorationplan.Shehas7yearsofprofessionalrestorationexperienceinCaliforniaandisa
CertifiedProfessionalinErosionandSedimentControl.PriortojoiningtheLandConservancysteamshe
workedonprojectsalongtheSacramentoRiverwithSalixAppliedEarthcareandpriortothatworkedfor
theVegetationEstablishmentandMaintenanceStudyatCaliforniaPolytechnicStateUniversity,SanLuis
Obispo.
TheprojectsuponwhichthisguideisbasedwereimplementedprimarilythroughtheLandConservancy
ofSanLuisObispoCounty,anonprofitlandtrustservingSanLuisObispoCounty.Theorganizationhas
beeninvolvedinhabitatrestorationforover20years.Throughouttheseprojects,wehavelearneda
greatdealaboutthefieldofhabitatrestoration,includingmanypitfallsandcommonchallenges
associatedwithworkinginaripariansystem.Alloftheknowledgewehavegainedhasprovidedfeed
backintosubsequentprojectsandgreatlystreamlinedconstruction.Toaddtothisfieldguide,wehaveenlistedtheassistanceofsomeofourlocalpartners,aswellasourrestorationfriendsfromthroughout
thestate.Theirtipsarealsoincludedinthisguidetobroadentheapplicabilityofthisguidetoinclude
otherpartsofCalifornia.Thetipswesharewillhelpreadersavoidcommonmistakes,ensuretheyhave
materialsonsitetodealwithemergencies,andgetmorehighqualityworkdoneforlessmoney.
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Acknowledgments
Whenwestartedthisguide,weknewthatourexperienceswerelimitedbytheprojectswehavehadthe
opportunitytoworkon.Toexpandtheknowledgebaseofthisguide,wesoughtthecommentsofsome
ofourlongtermpartnersonrestorationprojects,aswellassomeofourfellowrestorationprofessionals
fromotherpartsofthestatetogleaninformationthatwillbehelpfulstatewide.Wewanttothankthe
manyotherrestorationprofessionalsthathavecontributedtothisfieldguidebysharingtheirinsightsoncommonrestorationchallenges.
DaveHighlandFishHabitatSpecialist,CaliforniaDepartmentofFishandGame
MeredithHardyFishHabitatSpecialist,CaliforniaConservationCorps
PhillipLaFolletteRestorationProjectManager,CaliforniaConservationCorps
FreddyOtteBiologist,CityofSanLuisObispo
SydneyTemplePrinciple,QuestaEngineeringCorp.
SpecialthanksgoouttotheCaliforniaDepartmentofFishandGame,OfficeofSpillPreventionand
Response(OSPR).Byfundingthepreparationofthisguidetheyarecontributingtothegrowthofthe
restorationfield,whichisrelativelynewandexpanding.ThestafffromOSPRalsoplacedagreatdealof
faithandtrustintheLandConservancyofSanLuisObispoCountytocompletetheseprojectsandwere
ourmostvaluablepartnerintherestorationofSanLuisObispoCreek.
Literature Review
Thissectiondescribesexistingresourcesthatarecommonlyusedinprojectdesignandimplementation
ofriparianhabitatrestorationprojectsforstreamsinCalifornia.Eachcontainsvaluableinformationthat
isnecessaryforprojectmanagers.Theyarepresentedinanannotatedbibliographyformatbeginning
withthemostrelevantdocuments.
GaryFlosi,ScottDownie,JamesHopelain,MichaelBird,RobertCoey,andBarryCollins.California
SalmonidStreamHabitatRestorationManual,ThirdEdition.CaliforniaDepartmentofFishandGame.
ThispublicationisthemostoftenusedrestorationguideinCaliforniaandisessentiallyamustreadfor
allwhoareundertakingfisherieshabitatrestorationinCalifornia.TheCaliforniaSalmonidStream
HabitatRestorationManualpresentsacomprehensivesetofguidelinesthatbeginwithabriefhistoryof
thedevelopmentofrestorationprogramsinCalifornia.Thedocumentscitedaredescriptiveofstudies
thatdocumentthelossesofsteelheadandothersalmonidsthroughoutthestateandthevarious
prescriptionsforimprovingthestateofsalmonidfisheriesinCalifornia.
TheManualcontinueswithdetailedinformationonoverallwatershedassessmentandhabitatinventory
methodsthatareessentialforprojectsiteidentificationandprioritization.PartIIliststherecommended
contentsforawatershedassessmentandsometools,suchasmaps,photography,andhydrographsfor
formingawatershedactionplan.Naturalprocessessuchaserosionarebrieflydescribed.
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PartIIIincludesinformationonfisheriessamplingmethodsanddataanalysismethodssopopulations
canbeaccuratelyassessed.Thisworkisusuallydoneinadvanceofrestorationprojectsaspartofagoal
settingandprioritizationprocess.Theprojectplanningchapterpresentstheelementsofwatershedand
projectplanning,andtheimplementationchapterprovidescomprehensivedescriptionsofvarying
methodstostabilizestreambanks,improveinstreamhabitat,improvemigrationaccessforfish,and
properanchoringtechniquesforstructures.Themanualalsocontainsachapteronmonitoringand
assessmenttechniquesusedtoevaluateprojectsuccess.
AppendicesinthemanualprovidemoredetailedinformationonvarioustopicsincludingFishandGame
CommissionPolicies,classificationsofstreamssystems,determiningtheappropriatenessofplanting
fish,andotherlegislativefindings.Informationontheroleofhatcheriesisalsodiscussed.
TherestorationmethodsdescribedintheCaliforniaSalmonidStreamHabitatRestorationManual
containdetaileddrawingsonhowprojectsshouldbeconstructed.Thisdiscussion,however,doesnot
includeinformationoncommonproblemsthatoccurinthefield.
Griggs,Dr.ThomasF.2008CaliforniaRiparianHabitatRestorationHandbook,CaliforniaRiparian
HabitatJointVenture.
TheCaliforniaRiparianHabitatJointVenturebeganin1994andisfocusedonriparianhabitatsasthey
relatetoCaliforniabirdspecies.Thegoalofthishandbookistoprovidepractitioners,regulators,land
managers,planners,andfunderswithbasicstrategiesandcriteriatoconsiderwhenplanningand
implementingriparianconservationprojects.Theinformationinthishandbookisbasedonexperience
onriversystemsinCaliforniasCentralValley,buthasinformationthatisbroadlyapplicablestatewide.
Thispublicationprovidesageneraldescriptionofriverineecology,restorationterms,salmonidlifecycle
information,humanimpactsonripariansystems,andtherestorationplanningprocess.Therearebasic
recommendationsforthedesignprocessforrestorationprojectsalongwithmonitoringprotocolsanda
reviewofthetypesofpermitsrequiredformostprojects.Thetechnicalmethodssectiondiscusses
projectimplementationandisformattedfrombothproandconperspectivesthatlookatvarying
practicesrelatedtofieldpreparation,planting,irrigation,plantprotectors,andlaborresources.
USEPA,2000.PrincipalsfortheEcologicalRestorationofAquaticResources.EPA841F00003.Office
ofWater(4501F),U.S.EnvironmentalProtectionAgency,WashingtonDC.4pp.Foundonlineat
www.epa.gov/owow/wetlands/restore/principles.html.
Thispublicationprovidesalistofguidingprinciplesforriparianrestorationprojectsextractedfromthe
commonexperiencesoftheWatershedEcologyteam,U.S.EnvironmentalProtectionAgency(EPA)
OfficeofWetlands,Oceans,andWatersheds.Theseprinciplesarebroadinnatureandrepresent
conceptualapproachestorestoration.Thepublicationdoesnotofferspecificguidanceonindividual
restorationpractices.
EcologicalRestoration,ATooltoManageStreamQualityisamanualdevelopedbytheU.S.EPAthat
focusesonstreamrestorationtoimprovewaterquality.Theentiremanualisonlineat
http://www.epa.gov/owowwtr1/watershed/restdoc.html.Ch.6hasspecificcase
studies.http://www.epa.gov/OWOW/NPS/Ecology/
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TheEPAmanualisbasedmoreonpracticesusedtoprotectandenhancewaterqualitythanfisheries
habitat,butthepracticesthatarepromotedareconsistentwithimprovinghabitatthroughrestoration
techniques.Themanualdefinesrestoration,discussestheregulatoryframeworkofwaterquality
legislationestablishesthelinksbetweenrestorationprojectsandwaterqualityimpacts,providesa
decisionmakingguideforpractitioners,anoutlineforwatershedassessment,andhasasectionon
monitoring.
Intheirguide,theEPAstatesanimportantrealizationintherestorationfield,thatrestorationisnotyet
aperfectedapproachwithaccurateandprecisepredictivecapabilitiesand,infact,isstillanexercisein
approximation.Additionally,becauseecologicalsystemsarecomplexandmaytakeyearstoreach
equilibriumorfullydemonstratetheeffectsofrestorationandothermanagementactivities,seeingor
measuringresultsofrestorationeffortsmaytakealongtime.TheEPAmanualalsorecommendsan
ecologicalapproachtorestorationandacknowledgesthatoftentimesthesolutionstostreamproblems
maybemultifaceted.
Certaintechniquesaredescribedintheappendicesinageneralform;therearenospecific
recommendationsforaspectsofconstruction.
Riley,AnnL.1998.RestoringStreamsinCities:AguideforPlanners,Policymakers,andCitizens.Island
Press,WashingtonD.C.
AnnRileypresentsacomprehensiveviewofthefieldofurbanstreamrestoration,beginningwitha
reviewofecologicalvaluesofstreamsandidentifyingthetypesofprofessionalsthatareultimately
neededtoundertakesuchrestorationprojects.Thereisaveryinterestingdiscussionofthehistoryof
urbanstreamrestorationandthestatusoffederalprogramsfromagenciesidentifiedasresponsiblefor
urbandrainages.Theremainderofthebookprovidesaguideforurbanresidentsonhowtobegina
projectfromtheperspectiveofcitizenbasedrestorationorganizationsandsomeofthebasicsof
restorationprojectdesign.Thisbookisnotintendedtobearestorationmanual,butprovidesimportant
informationforcitizenstogetinvolvedinthecareandrestorationofurbanstreams.
FieldGuideforConstructionSiteDewatering,CaliforniaDepartmentofTransportation,Construction
Division,CTSWRT01010.Sacramento,CA.2002.
TheCaliforniaDepartmentofTransportation(Caltrans)FieldGuideprovidesCaltransResidentEngineers
andfieldstaffwiththeinformationnecessarytomanagedewateringoperationsonconstructionsitesto
maintaincompliancewithFederalandStatewaterqualityprotectionregulations.Thismanual
establishesuniformpoliciesandguidelinestosupportdewateringoperationsonconstructionsites
managedbyCaltrans.Themanualcontainsinformationregardingthenecessarypermitsforprojects
requiringdewatering,optionsavailablefordewatering,issuesrelatedtowaterpollution,assessingwaterqualityandestimatingdischargeparameters.Thereisalsoinformationrelatedtoworkingwith
adjacentlandownersthatmaybeaffectedbytheproject.Appendicesincludeoptionsfordealingwith
turbidwaterandsedimentation,requirementsfromtheRegionalWaterQualityControlBoards
(RWQCB),dischargepermits,andNationalPollutionDischargeEliminationSystem(NPDES)
considerations.
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AppendixApresentsspecificwaterqualityrequirementsforeachoftheStates9RWQCBregions.
AppendixBprovidesdetailedcomparisonsofvaryingmethodsforcontainingandmanagingsediments
fromdewateredsites.Eachmethodisdescribedwithparameterssuchasflowrange,footprint,product
availability,equipmentrequired,andrentalandmaintenancecosts.AppendixCcontainswaterquality
anddischargeassessmentmethodologiesandstandardizedforms.AppendixDcontainspermittextfrom
theRWQCBandtheNPDES.
Asaguide,theCaltransmanualismostusefulforevaluatingoptionsmorethanaguideonbuildingor
installingdewateringsystems.Forspecificguidelinesforconstruction,thismanualreferencesthe
CaltransStormWaterQualityHandbookentitledConstructionSiteBestManagementPractices
publishedinMarch,2003.Seethereviewofthisdocumentbelow.
Thisisatechnicalmanual,sothereissparseinformationspecificallyaboutpotentialfisheriesimpactsof
projectsitedewatering.Thisis,however,oneofthemorecompletesourcesforinformationabout
dewateringoptionsandsedimentcontrolfromatechnicalstandpoint.Muchoftheinformationinthis
manualwillbehelpfulforrestorationprojectproponents.
ConstructionSiteBestManagementPractices.CaltransStormWaterQualityHandbooks,PublishedbytheStateofCaliforniaDepartmentofTransportation.March2003.
ThismanualwasgeneratedtoguideCaltransinimplementationoftheagencysNPDESpermitthat
regulatesdischargesfromCaltransconstructionsites.Themanualisextensiveandincludessections
describingBestManagementPractices(BMPs)associatedwithconstructionprojects.Manyofthese
BMPswillbeusefulforrestorationprojectmanagers.Themanualdescribestheselectionand
implementationofconstructionsiteBMPsincludingTemporarySoilStabilization,TemporarySediment
Control,WindErosionControl,TrackingControl,NonStormWaterManagement,andWaste
ManagementandMaterialsPollutionControl.Avaluableappendixprovidesguidanceontheselectionof
temporarysoilstabilizationcontrols.
ThisdocumentisthemostcomprehensivelistingofprojectBMPsthathaswidespreadapplicabilityand
useinCalifornia.Prosandconsforeachalternativelistedgiveaprojectmanageraheadstartin
planningmanyaspectsofprojectimplementation.
ErosionandSedimentControlFieldManual.RegionalWaterQualityControlBoard,SanFranciscoBay
Region.DistributedbyFriendsoftheSanFranciscoEstuary,Oakland,CA.
Whilenotspecifictosteelheadrestorationprojects,manysuchprojectsincludeerosioncontrolasa
primarypurposeorassociatedprecaution.Thismanualwaspreparedforthepurposeofeducating
constructionprojectmanagers,andconsistsofaseriesofBMPsforerosionandsedimentationcontrol.
Thispublicationdifferentiateserosioncontrolfromsedimentcontrol,whereerosioncontrolis
protectingthesoilsurfacetopreventsoilfrombeingdislodged,andsedimentcontrolishandlingsoil
particlesmobilizedbyerosion.Theauthorspresentasetofguidingprinciplestopreventerosionbefore
ithappensthatincludedescriptionsofgradingmethodsandimportanttimingfactors.Thereisverybrief
descriptionoftheimpactsofclearingvegetationandgradingandthebenefitsofminimaldisturbance.
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IncludedinthemanualisasetofBMPsthataredescribedinsomedetailandwillbequiteusefulfor
restorationpractitioners.Theseincluderecommendationsforprojecttiming,gradingwiththecontours,
terracing,theproperuseofnetting,mats,andblankets,seedingandmulching,dustcontrol,useoffiber
rolls,streamcrossings,culvertoutletprotection/energydissipation,checkdams,siltfencing,straw
bales,sandbags,draininlets,andportablesedimenttanks.Theinformationcontainssufficientdetailto
beveryuseful.Someoftheserecommendationswillbetouchedoninthisfieldguide.
McCullah,JohnandDavidGrey2005.EnvironmentallySensitiveChannelandBankProtection
Measures.NationalCooperativeHighwayresearchProgram,Project2419,TransportationResearch
Board,WashingtonDC.
Thisreportdescribesausefullistofbiotechnical,orbioengineered,streambankstabilizingmethods,and
comeswithaninteractiveCDwithawealthofinformationonstreambankerosioncontroltechniques.
AlsoincludedontheCDisadecisionmakingmodelthatwillhelpprojectproponentschoosethemost
appropriatemethodgiventhesiteproperties.Thereare44techniquesinthereportandtheywere
arrangedinto4categories(1)RiverTraining,(2)BankArmorandProtection,(3)RiparianandStream
Opportunities,(4)SlopeStabilization.Withinthesecategories,thereisathreelevelratingsystemthat
accountsfortheamount,quality,andreliabilityofavailableinformationusedtodeterminetheproject
approach.
ThesoftwareincludedontheCDiscalledGreenbank.Itisarulebasedselectionsoftwaredesignedto
helptransportationengineersselectmethodsforerosioncontrol.Anassociatedknowledgebaseis
includedthatcontainsthedetailedrationaleandreasoningbehindtherecommendationsmadebythe
software.Theverycomprehensivesetofreferencesinthispublicationwillbeofgreatvalueforthose
seekingmoreinformationonerosionandsedimentcontrolusingenvironmentallysensitivetechniques.
McCullah,John2006.DirtTime:SeasonOneDisk3BlinkWorksandSalixAppliedEarthcare.
Thisvideopresentationtakestheviewerthroughtheconstructiontechniquesnecessarytobuildcertain
typesofbioengineeredbankstabilizationprojects.Thevideodocumentationofactualproject
instructionisveryusefulinunderstandingsomeofthecomplexitiesinvolvedinprojectconstructionand
projecttypeselection.Thisisoneofthemoreusefulreferencesforconstructionpracticesandsomeof
therecommendationswillbeincludedinlatersectionsofthisfieldguide.
Project Planning
Muchoftheworkrelatedtoriparianhabitatrestorationhappenslongbeforetheshovelhitsthesoil.In
thischaptertheprocessofprojectselectionisdiscussed,aswellassomeofthecrucialelements
necessarytosuccessfullyimplementaproject.
WatershedAnalysis
Ideally,allrestorationprojectsshouldbeundertakeninthecontextofaplanthatrecognizeswhatis
happeninginthegreaterwatershedwithinwhichthesiteislocated.Thepurposeoftheplanistolayout
howwatershedresourceswillbeprotectedandrestoredbasedonsolidsciencebasedapproaches.In
someemergencysituations,projectsmayneedtobebuiltwhetherthereisawatershedplanornot.
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Organizationsinterestedindoingrestorationworkcanplanaheadforfutureprojectsbyhavingthe
watershedplanpreparedinadvanceoftherestorationwork.Manyrestorationprojectsarealso
proposedthroughgrantprograms,andawatershedplanisanessentialprerequisitetobecompetitivein
securinggrants.Withoutknowledgeoftheprocessesoccurringinthewatershed,itisnotpossibleto
knowifanyoneprojectwilladdsubstantiallytoeffortstorestorevitalecologicalfunctions.Awatershed
planwillplaceprojectprioritiesbasedoncostsandbenefitssoitisclearthatavailablefundingis
grantedtoprojectsthatshowapositivecosttobenefitratio.Ifthewatershedbeinganalyzeddoesnothaveaplan,thenthefirststepshouldbetostudythewatershedandwriteaboutit.
Thewatershedplanwilldescribethestatusoflocalstreamsandfisheries,identifythemainthreatsand
causesofdegradation,andprescribecurativeactionsforspecificareasofthestream.Theplanshould
alsosetprioritiesforfutureactions.Normallythesearegeneralprescriptionsforspecificreachesof
stream,butmostrecommendspecificprojectswherepermissionofthelandownerhasbeengranted.
TheCaliforniaSalmonidStreamRestorationManual,publishedbyCDFG,isanexcellentsourceof
informationabouthowtoscopeyourplanandwhattheessentialelementsoftheplanshouldbe.The
U.S.EPAalsopublishestheHandbookforDevelopingWatershedPlanstoRestoreandProtectOur
Waters,publishedinMarch2008.ThereferencenumberisEPA841B08002.Theentiredocument
canbefoundathttp://www.epa.gov/owow/nps/watershed_handbook.
Researchingandwritingawatershedplanisoftendoneincollaborationwithstakeholdersinthe
watershed.Thesewillincludelandowners,governmentleaders,agenciesanddepartments,citizens,
businessinterests,potentialserviceproviderssuchasengineersandmaterialsproviders,contractors,
andmanyotherprofessionals.Eachmaycomewithdifferentknowledge,experiences,concerns,and
capabilities;workingtogethermakestheplanstronger
andmoreuseful.Itisvitalthatallstakeholdersarenot
justgiventheopportunitytoparticipateinformingthe
plan,butactivelyencouraged.Whenallpartieshave
someownershipoftheprocessandresults,theplan
ismorelikelytobefollowed.
ProjectPlans&Designs
Planningforrestorationprojectsisateameffortand
shouldincludeaninterdisciplinaryapproach.Itis
essentialtoengagebiologists,hydrologists,
contractors,engineers,permittingagencies,landowners,andotherswithspecificskillsandinterests.
Engagingotherrestorationorganizationstosharetheirexperiencesisalsovaluable.Withinputfromall
yourpartnersyouareabletothinkthroughtheprojectgoalsandmethodsthatwillyieldahighquality
project.
Theprojectdesignteamshoulddiscusseachaspectoftheplanintermsofalternatives.Thereare
usuallymultipleapproachesthatwouldachievesimilarresults,sothedesignteamshouldevaluatethe
meritsofeachalternativewithrespecttocostssoprojectdesignscanaddresstherelativevalueforthe
money.Designersshouldalsoconsideralternativestoaddresspotentialareasofcompromise.Most
restorationspecialistswanttodothemostbiologicallybeneficialdesignforeveryproject,but
sometimesthatprojectdesignconflictswithcompetinginterests.Forexample,projectstoimprovefish
InSanLuisObispo,CAtheearlywatershed
planningeffortsoftheLandConservancy
establishedstandardstreamreachesto
describespecificstreamareas.Thesewere
usedtoassignprioritiesforcertainproject
types.Thesereacheswerelateradoptedby
theCityandCountyofSanLuisObispofor
futurestudiessoallnewinformationcould
beseeninacommongeographiccontext.
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passagethroughpublicinfrastructure,suchasculverts,willalsoneedtoaddressflowcapacitiesand
floodingissues.Inmanycases,theprojectdesignisacompromisethatprovidesforthebestpossible
fishpassagewhilemaintainingtheeffectivenessofpublicinfrastructure.
Belowaresomeadditionaltipsonprojectdesigns.
1. Itishelpfultostartwithadesignphilosophythatbestconformstothenaturalfunctionsofthestream.Thebestalternativetoachievethisisthemostappropriate.Thenassitechallenges,andinsomecasespublicrequirementsdictate,adjustprojectssystematicallytoaddressconcerns.
Thegoalshouldbetoachievethemostnaturalprojectallowedthatwillstillmeetfunctional
goals.
2. Someofthemostimportantinformationforprojectdesignswillcomefromahydraulicstudyofthewatershed.Thesestudiesmodelpredictedflowratesandstreampower,andcanbeusedto
evaluateprojectalternatives.Mostpublicworksorfloodcontrolagencieshavemasterdrainage
plansanddesignhydrologystudiestheyuseinevaluatingprojects.Theseshouldbeconsulted
byprojectdesignengineers.Mostjurisdictionsalsohavespecificanalysisprocedureswhich
mustalwaysbemetforprojectapproval.
3. Inthecaseofaprojectthatinvolvespubliclyownedculverts,modelingflowforbeforeandafterconditionsisaprerequisitetopermitapproval.Ifthewatersheddoesnotalreadyhaveamaster
hydraulicstudy,workwithstakeholderstoproposeit.Thisinformationgenerallyhaslasting
valueandcansavesubstantialfundswhencomparedtodoingsmallerlocalstudiesformany
projects.
4. Whenproposingaprojectonpubliclyownedinfrastructure,itisessentialtoincludetheagencyresponsibleforthestructureindiscussionspriortothedesignprocess.Invariably,thereare
specificrequirementsandstandardstomeet,andevenstafftimefromtheagencywillalsoneed
tobeapproved.Donotbeginanydesignworkbeforesecuringpermissionandacommitment
fromtheresponsibleagency.Whenacommitmentismade,bepreparedtoworkcloselywith
agencystaffandadesignengineer.
ProjectPermits
Securingpermitsforworkinastreamisafieldinandofitself,andpresentsitsownchallenges.Inmost
cases,therewillbefederal,state,andlocalpermitsrequired.Someemergencycaseprojectsmaybe
exemptfromspecificpermits,orpermitsmaybeacquiredafterthefactwhenapublicagencyis
respondingtoemergencysituations.
Acquiringapermitfornonemergencyworkrequiressubstantialforethoughtintheprojectdesign
phase.Aprojectmustbeplannedwithknowledgeofspecificrequirementssoaccommodationsare
madeforpermitcompliance.Belowaresometipsonsecuringpermitsforyourproject.
1. Themostimportanttipregardingpermittingaprojectistostartasearlyaspossible.Permittingarestorationprojecttakessubstantialtimeandhavingtowaitonapermittobeginworkcan
complicateyourconstructionplanningandscheduling.Onthesouthcoast,ourconstruction
seasongenerallyendsonOctober15th.Ifyouhaveaprojectthatwilltakeseveralweeksor
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months,thepermitsneedtobeinhandmuchearlier.Itisnotunusualtobeginthepermitting
processoneyearormorebeforeconstruction.
2. Ifpossible,discussyourprojectwitharepresentativefromeachregulatoryagencypriortosubmittingthepermit.Thisisagoodwaytobuildlongtermrelationshipswithregulatorsso
theycanbecomemoreconfidentinthequalityofyourwork.Thisisalsothebestwaytolearn
whatissuesyourregulatorismostconcernedaboutsoyoucanbesuretoadequatelyaddress
theseconcernsinyourprojectdescriptioninyourpermitapplicationpackage.Oftentheywill
havespecificrecommendationsthatwillenhanceyourproject.
3. Onceyourpermitapplicationhasbeensubmitted,itwillbenecessarytoshepherditthroughtheprocessviafrequentcontactwithregulatorystaff.First,itiscriticaltocontactagenciesto
confirmreceiptofthepermitrequestandtolearnwhichstaffmemberwillbeprocessingyour
request.Thisshouldbedonewithintwoweeks.Thenfollowupeverytwoweeksorsotomake
surethatcertainprocesseshavebeeninitiated.
4. Asorganizationsdedicatedtorecoveryofimportantspecies,projectproponentsshouldbewillingtodoanythingpossibleorfeasibletoprotectlistedandspecialstatusplantsoranimalsduringaproject.Forthisreason,wehavetakentheapproachthatallofourprojectshavethe
potentialtoaffectthesespeciesandwesimplyassumetheirpresenceonsite.Withthis
assumption,wedevelopavoidancemeasurestoprotectallofthesespeciesduringconstruction.
Evenifthereissomeadditionalcost,wefindthisassumptiontobegoodinsurance.Ithasnever
servedourprojectstotrytoassertthatthesespeciesarenotpresentjusttoavoidpracticesthat
weshouldbedoinganyway.
ProjectFinancing
Beforeundertakingaproject,itwillbeimportanttothinkthroughhowyouwillpayforthework.Ifthe
projectisfundedbyagrant,itiscommonforpaymenttocomeinarrearsafteraninvoicehasbeen
submitted.Thismeansthattheorganizationusuallyhascapital(ordebt)investedintheprojectbefore
theygetpaid.Mostcontractswithyourcontractorshavepaymenttermsof30daysnet,meaningyou
owethemfundsin30days.Itisunlikelythatyouwillhavesimilartermsinyourcontractwiththe
grantor.Itismorecommonthatyouwillgetpaidin60to90days.Projectmanagerswillneedtofigure
outhowtopaycontractorswhilewaitingforgrantfunds.
Anotherfinancingissueisthecommonpracticeofgrantingorganizationswithholding10%ofeach
invoiceuntilthegrantiscomplete.Thisisostensiblytomakesurethatthegranteeactuallyfinishesthe
project,butitcanalsocomplicatefinancing.Withlargeprojects,suchasconstructionofa$1Million
bridgeorculvert,theprojectproponentwillbe$100,000shortofthefundsnecessarytopayfortheworkuntiltheentireprojectiscomplete.Evenforsmallermultiyearprojectsitiscommontobecarrying
thedebtonbehalfofthegrantor.Debtcostsmoneytoo,soprojectcostsactuallyincreaseduetoshort
andlongtermdelaysinpayment.Belowarethreestrategiesforhandlingprojectfinancing.
1. Alineofcreditfromabankcanbeavaluabletoolinmanagingprojectcosts.Itprovidesavailablecashsocontractorscanbepaidinatimelymanner.Inordertogetalineofcredit,the
organizationneedstohavesolidfinancestoshowcreditworthiness.Sincenonprofit
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organizationsgenerallycannotputupassetsassecurityforthedebt,theseareusually
unsecuredbusinesslinesofcredit.Inconsideringthelineofcreditoption,bepreparedforstrict
managementofdebtasitrelatestoprojectcosts.Likeacreditcard,balancescangrowandthis
isrealdebtthatmustbepaidoff.Beforegoingthisroute,theorganizationsBoardorTrustees
willneedtodecideiftheyarewillingtotaketheriskofassumingdebtandpreparingpolicies
associatedwiththisformoffinancing.
2. Asecondoptionisaspecificconstructionloanthatisbackedbythegrantcontract.Again,creditworthinessisaprerequisite.Mostcommunitybanksarerequiredtodosomelocal
communitybenefitlending.Ifyouhaveacloserelationshipwithabankyoumaybeableto
negotiatecredit.
3. Workwithyourcontractoronpaymenttermsandworktosecuremoretimetopay.Anyadditionaltimemeanscarryingdebtforashortertimeperiodandcansaveondebtcosts.With
largercontractingfirms,wehavebeenabletonegotiatetermsofupto60days.Thismakes
themthebankerfortheproject.Usuallyonlythelargestcompaniescancarrythesecostsas
mostsmalleroperatorsdonothavethecapacitytodothis.Whenpossible,negotiatesothat
youcanincludeawillpaywhenpaidclauseinyourcontracts.
LandownerCoordination
Whenworkingonprivateproperty,coordinatingtheprojectwiththelandownerisveryimportant.The
landownerneedstobecomfortablewiththeprojectdetailsandbothpartieswillwantsomewritten
understandingoftheirrespectiveresponsibilitiesandliabilities.Belowaresomespecificitemsthatneed
tobearticulatedinanagreementwithalandowner,andconsideredbytherestorationorganization.
1. Theagreementwiththelandownershouldcontainafullprojectdescriptionthatincludesthespecificdescriptionofprojectsiteaccess.Thisincludeswhereequipmentwillenterthe
property,whereequipmentwillbestoredwhennotinoperation,wherestagingoperationswill
takeplace,andwhereturbidwatercanbedischargedifnotinasedimentcatchmentthat
returnswatertothestream.Itisalsocommontospecifytheconditionsofaccesstothe
landownersproperty.Inmostcases,specifythataccessislimitedtotheneedsoftheproject.
2. Alegalagreementcalledanonexclusivelicenseagreementmaybeusedtolayouttheresponsibilitiesofbothparties.Insomecases,thesewillbeexclusivelicenses.Theagreement
mustspecifythatthelandownerisnottotakeanyactionsthatarecontrarytotheprojectgoals
suchasmodifyingtheworkbefore,during,orafterconstruction.Thisagreementisalsousedto
assignliabilitiesanddetermineaschedulefortheproject.
3. Liabilitycoverageisprobablyoneofthemostimportantpartsofanyworkingagreement.Itiscommontoprovidesomeformofindemnitytothelandownerforinjuriesordamagesthat
occurasaresultoftheproject.Thelevelofindemnityyouextendtoanylandownershouldbe
determinedinconsultationwithattorneysforbothparties.
4. Anyrestorationorganizationthatwillbeengaginginphysicalprojectsneedstoevaluatetheirorganizationsinsurancepoliciestobesuretheyarecoveredforpotentialdamagescausedby
theproject.Typesofinsurancemayincludeliabilitycoverage,auto/vehicleinsurance,herbicide
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applicationinsurance,directorsandofficersinsurance,andworkmanscompensationinsurance.
Anumbrellapolicyisalsoadvisable.Thespecifictypesofinsuranceandamountofcoverageare
bestdeterminedinconsultationwithyourinsuranceagent(s).
Contracting
Forallbutthesimplesthandbuiltand/orplantingprojects,contractorswillbehiredtoconstructthe
project.Theycallbuilderscontractorsforareason,becauseacontractarticulatesallresponsibilities.Theliabilitiesassociatedwithworkinandalongcreeksdemandthatworkbecompletedusinglicensed
contractorsandhaveafirmcontract.Thecontractarticulatestheconditionsandresponsibilitiesunder
whichtheprojectisconstructed,suchasthecost,schedule,billingprocedures,andassignmentof
liabilities.
Inmanycases,theselectionofacontractorisbasedona
biddingprocess.Thisprocessisdesignedtoelicit
competitionamongcontractorsinanattempttogetthe
bestvalueorprice.Throughthebiddingprocess,
contractorsstatetheirunderstandingoftheprojectgoalsandtheirqualificationstoperformthework,listtheir
ratesforspecificpeopleandequipment,andstatean
estimatedcostfortheproject.Whenabidisaccepted,it
isusuallyforalumpsumthatwillbepaidtothe
contractorforthework.
Itmaybethecaseinsomeareasthatlocalcontractors
willnotbidonrestorationprojects.Thismaybethattheprojectsarenotlargeenoughandcontractors
onlywanttoputalotofeffortintopreparingabidiftherewardofwinningislarge.Somecontractors
mayalsofearworkinginacreekduetotheliabilitiestiedtopossibleenvironmentaldamageor
violations.Itmaybenecessarytobeproactiveinencouragingbids.
Belowaresomepointstoconsiderwhenworkingwithcontractors.
1. ThebestwaytoensurequalityconstructionistoworkwithaClassAlicensedcontractor,alsocalledaGeneralEngineeringContractor.AGeneralEngineeringContractorisacontractorwhose
principalcontractingbusinessisinconnectionwithfixedworksrequiringspecializedengineering
knowledgeandskill.Thisclassofcontractorisrequiredtohavespecificskillsassociatedwith
workonandwithinwaterways.Aproperlyskilledcontractormaycostabitmore,butwilllikely
getworkdonefaster,better,andmoreefficiently.
2. Whenbiddingworks,considerprequalifyingcontractorsandonlysolicitbidsfromthosethatmeetthequalifications,suchasClassAcontractors.Thiscanproveimportantbecauseitisfairly
commontogetlowbidsfromunderqualifiedbidders.Lowbidsalsotendtoresultinmore
changeorderrequeststhatbumpthepricesafterthecontractissigned.Whengoingwiththe
lowbidder,payparticularattentiontotheirexperienceandalwayscallreferences.Thephoto
belowshowsalowbiddergoingafterasteelreinforceddamwithahammer,yieldingonly
cosmeticdamage.
Awordonbidding
Mostgovernmentagencieshavespecific
proceduresforrequestingbidsforpublic
worksprojects.Itislesscommonfornon
profitgroupstohavethese.Nonprofit
organizationsarewisetoborrowsomeof
thebiddingproceduresfromyourlocalcity
orcountygovernmenttoensurethatthe
processyieldsafaircomparison.
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3. Whenreviewingabid,lookthroughtheequipmentlistofferedtoensurethatthe
contractorhasaccesstoanyspecialized
equipmentthatmaybenecessary,suchasa
thumbattachmentfortheexcavatorbucket.
4. Whenrequestingprojectreferences,specificallyaskforreferencesassociatedwith
theirlastfourtosixprojects.Thisprovidesthe
mostcurrentsenseoftheirabilities,rather
thancherrypickedreferencesfromtheironly
twosuccessfulprojects.
5. Whenaqualifiedcontractorisfoundthatdoesgreatworkandunderstandsprojectgoals,considerhiringthemagainforotherprojects.Whencontractorsgainmoreexperiencewith
streamrestorationtheycanbeimportantpartnersoverthelonghaul.Bydoingthis,contractors
gainvaluableexperiencethatmayservefutureprojects.
6. Whenreviewingbids,paycloseattentiontothecontractorsunderstandingoftheproject.Besuretheyareawarethatthisisarestorationprojectanditmaybemorechallengingthanthe
worktheyhavedonebefore.Installingrestorationfeaturesoftentakesalotofpatienceby
equipmentoperatorsandtheyshouldunderstandthattheywillbeworkingcloselywiththe
onsiteprojectmanagerfromyourorganization.
7. Insomecases,atimeandmaterialscontractcansavemoney.Thesearemostlyforsmallerjobswherecostscanbecontrolledbyrigidmanagementoftheworkandcontract.Ifusingthistype
ofcontract,planspecificationsmustbeverydetailedandconstantsupervisiononsiteiscritical.
Thisiswhyitismostcommonforprojectstouseabiddingprocess.
TheFirstDayFieldMeeting&SafetyPlanning
Thefirstdayinthefieldonarestorationprojectismostlyamobilizationdaywhenequipmentand
materialsarriveandtheprojectteamgoesoverthedetailsofhowtheprojectwillgo.Dependingon
permitrequirements,theremayalsobeprescribedtrainingforthebuildingcrewonrecognitionand
protectionofspecialstatusspecies.Thisiswhentheprojectmanagerfromtherestorationgroup
establisheslinesofcommunicationbetweenthemselvesandthecontractingcrew.Beloware
recommendationsforthefirstday.
1. Iftrainingwillbeprovidedfortheproject,suchastrainingforprotectionofspecialstatusspecies,havetheentirecontractingcrewthatwillbeworkingontheprojectpresentforthis
training.Itisimportanttoletthecontractorknowthisinadvancesothetrainerdoesnotneed
tobecalledbacklaterfornewworkers.Besuretoschedulethiswiththeapprovedbiologistor
othertrainersoeveryoneisonschedule.
2. Projectmonitorsallneedtobeonsiteforthefirstdayaswell.Thesemaybemonitorsforbiologicalresources,culturalresources,andpossiblyNativeAmericanmonitors.Theywillhavea
roletoplayindiscussingimportantconstraintsonthesite,andastheprojectmanageritis
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importanttoclearlyarticulatetheroleofthemonitorstothecontractors.Particularly,if
monitorshaveauthoritytostopconstructionintheeventofathreattoresources,thisauthority
mustbecleartoeveryoneworkingonthesite.Monitorsarepartnersintheprojectanditis
alwaysbettertoworkcloselywiththemtoavoiddamagetospecialresourcesthantodealwith
aviolationofapermitcondition.
3. Makesuretherearecopiesofallprojectpermitsonsiteandletthecrewknowwheretheycanbefoundintheeventtheyareaskedtopresentthemtoanyregulatoryinspectors.
WorkingwithHeavyEquipment
Usingheavyequipmentisoftentheonlywaytoconstructlargeprojects.Itisimportant,however,to
knowthatheavyequipmentcanalsocauseagreatdeal
ofsitedamageinaveryshorttime.Itisimportantto
haveadiscussionwiththeequipmentoperatorstolet
themknowaboutsomeofthechallengesoftheproject
andwhatisexpectedofthemduringconstruction.For
somerestorationprojects,theprojectmanagershouldbepresentonsiteregularlyenoughtoensurethat
certainspecificationsarebeingmet.Considerita
responsibilitytomakesuretheoperatorsdontfailor
endupviolatingapermitcondition.
Belowaresomesuggestionsforworkingwith
contractors.
1. Priortobringingequipmentonsite,meetwiththecontractorsprojectmanageronthesiteanddiscussanyaccessconstraints.Workingalongcreekscanprovidecertainchallengesforaccess
andplansshouldbemadeinadvance.Truckdriversthatwillbedeliveringmaterials,suchas
bouldersortreetrunks,shouldalsoinspectthesitebecausesometruckshaveaccessand
deliveryconstraints.
2. Powerlinesareofparticularconcerninbringingequipmentontothesite.Ofteninruralareas,thewiresarerelativelylowcomparedtotheheightofanexcavatoronalowboytrailer.Inthese
cases,itmaybenecessarytoeitherdrivetheexcavatorinwiththebucketlowered,orthewires
maybeabletobetemporarilyliftedusingawoodenbrace.Powerlinesmustalwaysbemarked
withasignviewablebytheoperator(usuallyontheground).Inmostcases,theycantseethe
wiresfromthecab.
3. Iftheexcavatororothertrackedequipmentisdrivingintoasite,rememberthatmetaltrackscandoalotofdamagetopavement.Pavementshouldbeprotectedtoavoidliabilities
associatedwiththedamage.Plywoodissufficienttoprotectpavementandislowincost.A
thicknessofatleast5/8inchisrecommended.
4. Shootingsomevideooftheaccesstoasite,andfocusingonpotentialissues,isaneasywaytopreparecontractorstoenterthesitewithheavyequipment.Thiscansaveatripouttothesite.
Bouldersareusuallydeliveredinanend
dumptruck.Thesecanholdupwardsof
1820tonsofrockandgettopheavywhen
dumping.Theywillneedtodothisdump
onaflatsurface.Therefore,astagingarea
needstobedelineated.Nobodyshouldbe
nearoneofthesetruckswhenitis
droppingitsloadbecausethetruckcould
tiporthefallingrockscansendflying
shards.
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Thevideomayalsobehelpfulinshowingtheconditionofthesiteaccessareaspriorto
constructionsocontractorscanberequiredtomaintainthatbaselinecondition.
5. Establishingequipmenttrafficlanesonlargerprojectsensuresthattheequipmentdoesnotdamageanunnecessaryamountofland.Routesshouldavoidanyrareplantsorsteepslopes.It
isalsobestforaprojectsitetosetspecificareaswhereastreamcanbeaccessedfor
construction.Thisreducesthetotalareaofcollateraldamagefromtheequipmentaccessingthe
stream.
6. Whenworkingwithinastreamchannel,itisbestnottohaveanexcavatorinthenormallywettedpartofthechannel.Thisisbecauseheavyequipmentis,bydefinition,heavyandit
vibrates.Thecombinationofweightandvibrationcancreateliquefactionofthestreambed.
Beachgoerswillknowthatwhenyoupatwet
sand,waterrises.Whenthishappens,the
excavatormaysinkintothesubstrateandget
stuck.Italsocreatesaquicksandeffectinthe
channelthatcanbeasafetyissuewithpeople
onthesite.
7. Heavyequipmentisdangerous,anditisoftendifficultfortheoperatortoseewhatisbehindthem.Fieldpersonnelmustavoidtheallpartsofanexcavatorwhentheoperatorisinit.Most
peoplelookatthebucketasthedangerousend,butthebackswingswidewhenthebucketis
movingandcanstrikeunsuspectingpeoplebehindit.Itiswisetohaveaseparateaccesstothe
siteformachinesandpeople,andtoactivelyhelptheoperatortoknowwherepeopleare
working.Whenworkingcloselywithequipmentwearsafetyvestsanddonotapproachthe
machineuntilmakingeyecontactwiththeoperatorandgettinganacknowledgment.
8.Mostheavyequipmentsuchasbackhoes,hoerams,loaders,andexcavatorsmakeuseofhydraulicpowertolift,grab,push,orhammermaterials.Thehydraulicfluidflowsinrubber
hosesthatcanbreak,causingaspillintothestreamorstreamchannel.Thesespillsneedtobe
controlledrapidlytoavoidimpactsassociatedwiththespill.Alwayshaveaportableoilboom
andoilabsorbingclothsonsiteandwithinreachifaspilloccurs.Itiscommontoincludethis
requirementinthecontractwiththecontractor.
Illneverforgetthedaywehadthe
excavatorinthechannelandnoticedit
wassinking.Wegotitoutofthechannel
immediatelyandontoagradedplatform
onthestreambank.Aftermovingthe
equipmentweneededtogetintothe
channeltomakeanadjustmenttothe
diversionpipes.ACCCCorpsmemberwas
thefirstintothechannelandhesunk
nearlywaistdeepinthequicksand.Ittook
15minutestofreehimduetothesuction
effectofthemud.Thiscouldhavebeena
veryserioussafetyproblemhadthemud
beendeeper.BrianStark
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9. Heavyequipmentwillneedtobefueledandoccasionallylubricatedonsiteduringtheproject.Establishaspecificfuelingandmaintenanceareaonthesiteforthisactivity.Thisareashouldbe
atleast100feetawayfromanywatersource.Havingonlyonelocationforthisactivityishelpful
intheeventthereareanyspillsbecausetheareatocleanupisconcentrated.
Water Diversions & Work Site Isolation
Whenworkwillproceedinoradjacenttoastreamchannelandtheworkposesathreattowaterquality
orfisheries,itisoftennecessarytoisolatethestreamorcompletelydewatertheworksite.Thiswill
usuallybethefirstactivityundertakenandisoneofthemostimportant.Isolationanddewateringcome
withsubstantialrisksfortheaquaticlifeinthestream,thusaddingamuchgreaterlevelofresponsibility
forprojectmanagers.Thissectionwilldescribesomebasicmethodsofdewateringandisolatingstreams
andlistsomeimportantconsiderationstoreducethepossibilityofharmingfishordownstreamhabitats.
Waterdiversionscomeinseveraldifferentformsincludingprojectsiteisolationandfulldewatering.If
workisoccurringonjustonebankofthestream,itcanoftenbedonebysimplyisolatingtheclean
streamwaterfromanyturbidwaterintheworkzone.Isolationismuchlessinvasiveforaquaticlifeand
shouldalwaysbeconsideredbeforecompletelydewateringastream.
Whentheprojectwillbedoneintheactivechannelandrequiresequipmentaccesstobothbanksora
substantialpartofthestreambed,itwillbenecessarytodewatertheworksite.Dewateringisthepart
ofaprojectwheretherearethegreatestriskstofish.Duringthisprocess,waterisremovedfromthe
streamandallfishmustberemovedfromtheworkareaandplacedinsafehabitat.Thisisavery
complexprocessthatrequiressubstantialpreprojectplanningandwilloftenrequireadjustmentsinthe
field.Thisactivityalsorequiresspecificpermitsthatdescribetheacceptablemethodstouseandwhat
typesofmonitoringandreportingarerequired.
Thissectionintroducesafewoptionsanddiscussestheirprosandcons.Wewillalsolistsomecomplicatingissuesassociatedwithdiversioninstallations.Forthemostcomprehensiveguideto
methodsandpracticesassociatedwithwaterdiversionorsiteisolation,seeFieldGuidetoConstruction
SiteDewateringandConstructionSiteBestManagementPractices,bothpublishedbyCaltrans.
WorkSiteIsolation
Forprojectsiteswhereworkisoccurringoutsideofthemainchanneloranadjacentbank,itisusually
preferabletosimplyisolatethecleanstreamwaterfromtheconstructionarearatherthandewatering
thestream.Isolationispreferredoverdewateringbecauseitalsodoesnotinvolvesignificantfish
relocationorthemoreextensiveconstructionofdiversions.Thiscanbedoneanumberofdifferent
ways,andinsomecasestheprojectpermittingrequirementswillhavesomesayinhowthisisdone.The
mainobjectiveistoensurethatsedimentdoesnotenterthecleanstreamduringconstructionandthat
fishandotheraquaticresourcesarenotharmedordamaged.Allisolationstructuresmustbeplannedin
advanceandbedescribedinanypermitapplications.
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IsolationUsingStrawBales
Isolationsmaybefabricatedusingstrawbalesifthe
isolationisoutofthewater.Strawbalesare
effectiveforstoppingsedimentfromcomingoffa
gradedslopetowardthestream.Iftheisolationwill
actuallyrestinwateritisbettertousegravelbags
becausethestrawbaleswilldegraderapidlyandbehardtomovewhensaturated.
IsolationUsingCofferDams
Cofferdamsareoftenusedtoisolateprojectsites.
Theyareagoodmethodbecausetheyaregenerallylowincostandcanbebuiltbyhand.Acofferdamis
usuallybuiltwithsandbagsthatarefilledwithwashedgravelorcoarsewashedsand,andmayalso
incorporateplasticsheetingtoimprovetheeffectivesealofthestructure.Usingwashedrivergravel
(smoothstones)insidethebagsisagoodchoicewhenthebagisprimarilyusedforstructuralrigidityin
combinationwithplasticsheetingfortheseal.Bagsfilledwithsmoothwashedgravelwillnotsecrete
sedimentintothestream,theydrainquicklywhenwetmakingthemeasiertohandle,andthesmooth
gravelpreventstearingofthebags.Whentheprojectiscompleted,thesmoothgravelcansimplybe
depositedintothestreamchanneltoformhabitatandtemporarilybindconstructionsedimentsinthe
workzone.
Insomecases,therewillbeturbidwaterintheworkzoneandadownstreamisolationbarriermust
preventthiswaterfromescapingintothestream.Watercancomeupinanisolationzonethrough
streambedupwelling,butitalsocomesupduetothedisturbanceofsoilsintheworkzoneandpressure
causedbyequipmentinthechannel.Controllingthiswatercanbedifficultwhenwaterintheworkzone
buildsupandthewaterpressureforcesturbidwaterthroughtheisolationbarrier.Thisleakageofturbid
watercanbecontrolledbymanagingthewaterpressuregradientintheworkzonewithsubmersiblepumps.Pumpspullturbidwaterfromthework
zoneanddeposititoutsidethestreamchannel,
usuallyintoasedimentbasinorontoadjacent
landwhereitwontrunbackintothestream.
Inthesituationpicturedtotheleft,anisolation
weirwasbuiltbecausethepoolwastoobigto
dewater.Theweirismadeofgravelbagssealed
withplasticsheeting.Inthisapplication,tstakes
wereusedtoaddstructuralsupporttothecofferdamduetotheheightofthestructure.Itis
commonforallisolationstohavesomeleakage,
andthechallengeistokeeptheturbidwaterout
ofthestream.Thiscanbeaccomplishedbyrunningasingleelectricsubmersiblepumpandpumpingthe
turbidwaterintoholdingpondsoutsideofthechannel.Itwasnotnecessarytopumpoutallthewater,
ratherjustenoughtokeepthepressuregradientlowerintheworkzonethanoutsidetheworkzone.
Thiscausesthecleanwatertoleakintotheworkareainsteadofturbidwaterleakingoutofit.When
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managingwaterpressureontwosidesofaweir,itisimportantinmanycasesnottopumptoomuch
wateroutoftheworkzone.Ifwaterpressuregetstoolowintheworkzone,theweirwillimplodedue
towaterpressureoutsideoftheworkzone.Ifpressuregetstoohighintheisolationareatheweirwill
collapseoutwardly.
Whenusingthismethod,itisbesttoschedulethecompletionofworkeachdayatleastonehourbefore
turningoffthepumps.Thisgivesthesedimenttimetosettleoutoftheworkzonewaterbeforeallowing
pressuretoequalize.
CaseStudy#1Beingmindfulofsubsurfaceflows
OnStennerCreekwewerepouringaconcrete
wallalongonesideofasetoffishpassage
weirstokeeptheadjacentroadfrombeing
undercutbythestream.Thepoolpictured
herewassustainingapproximately15
steelheaddespitethelackofsurfaceflow.The
poolwasbeingfedcooloxygenatedwatervia
subsurfaceflow.Ourpermitsonthisprojectdid
notincludedewatering,soweisolated2/3of
thepooltoprotectsteelhead.Theremaining
partofthepoolwasintheconstructionarea
separatedbyacofferdam.Whilepouringthe
concrete,wesetupapumptoremovethe
slurryandcontaminatedpoolwater.Wefoundthatifwepumpedtheslurryouttoofast,wewouldpull
thegroundwaterawayfromthepool,andthefishbegangulpingforaironthesurface.Weshutdown
thepumpandthefishwerefine.Weadaptedtorunninganelectricpumpforshortperiodsandthen
turningitoff.Thiswassufficienttomanipulatewaterpressureandkeepslurrywaterfromenteringthe
pools,anditkeptthefishoxygenatedandthewater
clean.
CaseStudy#2Isolatingworkonadam
ThismodificationoftheMarreWeirinAvilaBeach
presentedaverychallengingisolationproject.The
projectinvolvedmanufacturingafishmigration
notchinasheetpileweir.Thenotchwascutout
andaweldedacapwasfittedoverittobolsterthe
strengthoftheweirandmaketheflowlessturbulentthroughthenotch.Isolationofthework
areawasnecessarytogetthewaterlowenoughto
performtheweldingontheupstreamside.
Thiswasacomplicateddiversionbecauseworkwasnecessaryattheupstreamsideofthedamandit
neededtoholdbackthewaterbeingimpoundedbythedam.Itiseasytounderestimatethepowerof
allthatwaterwhenitisstandingstillmostofthetime.Thediversionwasoriginallyconstructedof
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plywoodandlumberandsealedwithplastic.Problemsarosewhenthecontractorspumpedthewater
outoftheinside.Thelumberwasnotstrongenoughtoholdtheexternalwaterpressure.Itwasthen
reinforcedwithaluminumpiping,butthatfailedaswell.Ultimately,ittookaweldedsteelstructureto
holdbackthewater.
Forsiteswheresubstantialvolumesofwaterneedtobeisolatedandwaterpressuredifferencesare
high,thebestsolutionistoinvolvetheprojectdesignengineerinthedesignoftheisolationstructure.
Whileitcostsmoreupfront,itwillultimatelybesafer,savetimeandmoney,andallowtheprojectto
movethroughconstructioninamoreefficientmanner.
Inhindsight,itmayhavebeenwisertohaveusedanunderwaterwelderforthiswork.Whilemore
costlyperhour,itwouldhavesavedalotoftimespentontheisolationstructure.Anunderwaterwelder
washiredtodoaminorrepairthenextseasonwithgreatease.
MoreTipsonIsolations
1. Alwaysbemindfulofwaterpressureonbothsidesoftheisolationweirsoitdoesnotcollapse.2. Aseinenetcanbeusedpriortoconstructionoftheisolationstructurestomakesurenofishare
presentintheworkzone.
3. Disturbanceofthestreamcanbereducedifisolationstructuresarebuiltfromtheworkzoneside.Thatwaytheturbiditycausedbythecrewcanbeheldinsidetheisolation.
StreamDewatering
Whendewateringisnecessary,thereareseveraloptionstoconsider.Inmostcases,thediversionsare
builtusingcofferdamsandpipe,orapumpisusedtopumpwateraroundthesite.Inbothcases,there
isacompleteseparationbetweenthewaterandthechannel.
Thepartoftheprojectthatholdsthebiggestthreattofishistheinstallationofthediversion.Exercising
careinthisprocesscanavoidunnecessaryharmtofish.Inthefirststep,ensurethattheprocessof
removingfishfromtheworkareaisascompleteaspossible.Itisoftenthecase,however,thatthefirst
passofthefishrelocationdoesnotcatchallthefish.Itsbesttoassumethatthereisstillariskforfish
throughoutthedewateringandconstructionprocess.
FishRelocation
Priortodewateringasiteforinstreamwork,fishneedtoberemovedfromtheworkareathatwillbe
dryandisolatedduringconstruction.Specialpermitsarerequiredforthiswork.Dewateringandfish
relocationaretheprojectelementsthatposethegreatestdangerstofish.Belowareafewconstructionpracticesthatcansubstantiallyreducefishmortality.
1. Fishrelocationmayhavetwophases.Afirstphaseusuallyconsistsofusingseinenetstotrytogetfishoutoftheprojectreachandmakingsurethatnomorefishgetintotheworkzone
duringtheconstructionoftheisolationordewateringsystems.Asecondroundoffish
movementmayhappenafterthedewateringsystemsareinstalled,andusuallyinvolves
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reducingwaterflowtoencouragefishtoconcentrateinpoolswheretheycanbecapturedwith
dipnets.
2. Thedaypriortothedewateringandfishmovingactivity,manuallyremovevegetationgrowinginthewettedarea.Thisincludestheherbaceousplantsgrowingalongthewettedperimeteras
wellasdeadmaterialintheactivechannel,suchassycamoreleaves.Alsoremovelargecobble
anddownedwoodifpossible.Theremovalisdonegentlyandslowlybyhandsofisharenotharmed.Whenremovingthesetemporaryhabitatfeatures,fishtendtomoveoutoftheseareas
andthetotalnumberoffishtobemovedisdecreased.Italsohelpsduringthefishrelocation
becausefishcannothideamongthevegetationwhereitishardtoremovethemsafely.
Ultimatelythisresultsinlessstressonthefishandafasterrelocationprocess.Removed
vegetationusuallyconsistsofherbaceousplantsthatwillbedisturbedduringconstruction
anywayandregrowquicklyfollowingconstruction.
3. Withlargerhabitatelementsremovedfromthewettedchannel,seinenetscanbeusedtoexcludemostfishfromtheconstructionarea.Twoseinenetsareusedinthisprocedurewhere
oneisplacedatthedownstreamextentoftheexclusionarea.Thesecondisplacedinthechannelimmediatelyupstreamofthelowernetandkickedupstreambythenetters.Generally,
itisbesttomovefishinanupstreamdirectionbecausethesehabitatswillnotbedisturbed
duringconstructionandanyaccidentsduringconstructionthatmaycausehabitatdisturbance
downstreamdonotaffectthemovedfish.Insomecases,habitatavailabilitymayimpactthe
directionofseining.Ifthereisnoorpoorqualityhabitatupstream,fishmaybemoved
downstream.
4. Streamchannelbedsareusuallyuneven,sogapsbelowthenettingprovidefishspacestoavoidthenetting,soitislikelythattheseiningwillnotexcludeallthefishintheprojectreach.In
mostcasesitwillbenecessarytocontinuefishmovementduringtheconstructionofthe
diversion.Oncethediversionispartiallyintact,slowlyreducewaterflowtotheprojectreach.
Whenflowdrops,fishwillconcentrateinpoolsandcanbecapturedwithdipnetsordnets
quiteeasily.Itisimportanttohaveanumberofdifferentsizednetsonsitesothepropernetsize
canbeused.Usingnetsthataretoolargeortoosmallcanincreasetheriskstofishasnetsare
jostledintoposition.Oncefishareisolatedinthepoolspumpscanbeusedtopumpdownthe
waterlevelsifnecessaryandeasily
capturefish.Itiscriticalthatyour
pumpsareproperlyscreenedsothey
donotentrainanyfish.Itisimportant
duringtheconstructionofthedewateringcofferdamtonotinitially
divertallthewater.Rapidwaterloss
willresultinstrandedfishthatdidnt
makeittoapool.Rather,dewatersites
slowlyandleavesomeliveflowuntil
youareconfidentthatallthefishhave
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beenmoved.Besuretoremovetheseinenetsafterthediversionisinplacetoallowforfish
passagethroughthepipesduringconstructionactivities.
Amethodforfishcapturethatisgenerallyconsideredmoreeffectiveandsaferforfishis
electrofishing,orefishing.Inthismethod,atrainedspecialistusesabatterypacktoelectrically
chargethewater.Thishastheeffectofstunningfish.Stunnedfishfloateasilyintonetswithout
astruggleandregainconsciousnessin
thebucket.Anadvantagewiththis
methodisthatitdoesntrequire
chasingfish,soitcanbedonemore
slowlyandmethodicallywithout
jabbingnetsoutandpotentially
crushingfish.Itisadvisabletorequest
efishinginthepermitapplicationfor
allprojectsthatrequirefish
relocation.Makesureyouhavean
incidentaltakeprovisioninyourNOAA
FisheriesBiologicalOpinion(B.O.)beforemovinganyfishanywhere.
5. Whennettingfish,placetheminbucketsoffreshcoolstreamwaterandplacesomevegetationinthebuckettoblocksunlight.Itiscustomary,andoftenrequiredtocountthefishand
determineageclasspriortoreleasingthefish.Thesedataarelaterreportedtopermitting
agencies.Thesebucketsneedtobeemptiedfairlyoftenasthewatercanheatupandthe
dissolvedoxygencanbedepleted.Experiencedfishmovershighlyrecommendusingbattery
poweredelectricairpumpstooxygenatethewaterinthebuckets.
6. Itiscriticalthatfederallyapprovedbiologistsassistwithmovingfishandtheyshouldbeconsultedastohowtobestproceedundersiteconditionstominimizeharm.Also,besureto
consulttheconditionslistedintheBiologicalOpinionandotherpermits.Haveatleast3to5
peoplepresentunderthesupervisionofthebiologisttoassist.Precise,quickmovementscan
makethedifferenceinwhetherornotfishsurvivethemove.
SpecialConsiderations
1. Whenmovingfishinahighgradientstreamreach,itisdoublyimportanttomakesurethedewateringcofferdamdoesnotdivertallthewater.Highgradientreachesgodryveryquickly
aswaterflowsdownthroughthereachandcanstrandfishindrysections.
2. Animportantthingtorememberwhenusingpumpsinanareacontainingfishisthatpumpscansuckup(entrain)smallfish.Itisimportanttoscreenpumpuptakestopreventthis.The
screeningofthepumpintakemusttakeintoaccountthesizeofthefish,butalsotheintake
capacityofthepumpandtheamountofdebrisinthewater.Finescreeningreducesthe
effectivenessofthepumpandintakesarepronetodebrisaccumulation.Thebestwayto
preventproblemswiththeintakeistodesignaconcentriclayeringofscreens,withtheouter
layertrappingdebris,themiddlelayerexcludingfish,andthepumpintakeinthecenter.By
WhenapplyingforapermitthroughtheU.SArmy
CorpsofEngineers,projectmanagersshould
specificallyrequesthavingtheabilitytoelectrofishto
assistwithmovingfish,ifthesiterequiresit.TheArmy
CorpsthenseeksaBiologicalOpinionfromNOAA
Fisheriesregardingtherequest.NOAAFisherieswill
notassumethatprojectproponentsneedtobeableto
electrofish.
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expandingthescreenareaforthefishscreen,morewatercanpassthoughtothepump.A
bucketfullofholesmakesagooddebrisfilterandalargenetcanbeusedinthebucketforfish
screening.Bucketsfullofsmallholesandscreenedontheoutsidewithregularwindow
screeningarealsouseful.Screeningontheoutsideofthebucketpreventsthescreenfrom
implodingtowardthepumpintake.
Beyondtheissueofentrainmentoffish,thepumpsusedfordewateringandmanagingturbid
waterintheworkzonewillgetcloggedintakescreens.Itisoftennecessarytomonitorthe
intakesconstantlyandcleanthemrepeatedly.Itmaybenecessarytohavesomeonesitbythe
intakeandconstantlyremovedebrisfromtheintake.Aplasticscrubbrushmakesaneffective
intakecleaner.
StreamDewateringTechniques
Waterdiversionsaremostoftenbasedongravityflowthroughpipes,butinsomespecialcases,pumps
areused.Theseareconstructedusingcofferdamsandsomeformofpipe.Gravitysystemsareefficient
becausetheydontrequiremovingparts,theycanbeleftunmonitoredovernight,andtheyare
relativelylessexpensivethanpumpsystems.Pumpbasedsystemsneedtoberunningconstantly,sotheyneedtobemonitored24hoursaday.Theyalsoconsumealotoffuel,whichincreasesthecost,as
wellasthecarbonfootprintoftheproject.Pumpscanalsobreakdown,requiringfastactiontogeta
replacementpumpinservice.Beforeconsideringtheconstructionofadiversionforaproject,consider
whetheritmightbebettertohaveacontractorbuildthediversionbasedonsomespecificperformance
stipulationsplacedinthecontract.Itmaybethatthecontractorhasmoreexperienceinthisarea,andit
alsoplacestheresponsibilityofpermitcomplianceonthecontractorratherthantherestoration
organization.Ifthecontractordoesnothavetheabilitytodothisstep,itcanalsobecontractedto
experiencedconsultants.
Buildingacofferdamwithapipediversion
Forastandardcofferdamandpipediversion,youwillneedsandbagsfilledwithwashedsandorgravel.
Gravelispreferredbecause,asmentionedabove,thebagsarejustastructuralsupportforthe
visqueen,orsheetplastic,thatwillactuallyformtheseal.Thegraveldoesnotcontainfinesediments
thatcouldleachoutofthebagsandintothestream.Whenusinggravel,selectroundedgravelsoitcan
beleftinthestreamafteruse.Youwillalsoneedtheplasticsheetingforthesealandsomeformofpipe.
Acorrugatedplasticpipeisapreferredtypebecausetheyaretheeasiesttorepairifdamaged.Finally,
youwillneedbalingwiretoaffixtheplastictothepipe.
Thesizingofthepipescanvarydependingontheflowyouaretryingtodivert.Insomecasesprojects
haverequiredarigidplasticcorrugatedpipewithalargerdiameter.Theupsideisthatthispipecancarryalotofwater.Itisalsoverystrongandcansurvivesomebeating.Thedownsidesarethatitisrigid,
doesntdocurveswell,anditisveryheavy.Thesepipesarealsohardertorepairifdamaged.Ittakes
eitherheavyequipmentormorepeopletomovearound.Ingeneral,thisdiversionremainsinplace
duringtheprojectandcannoteasilybemoved.
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Onsmallerstreams,usingsmaller
flexiblecorrugatedpipein6and8
diametersmaybeeasier.Whileeach
pipeholdslesswater,multiplepipes
canbeusedtoachievethenecessary
flowcapacity.Smallerflexiblepipescan
conformtocurvesinthechannelandarelightenoughtobemovedduring
constructionwithoutdismantlingthe
diversion(seephotoatright).The
groovesmakethemeasytorepairand
seal.Generally,ifmorethanfoursmall
pipesareneededtoconveythewaterit
isbettertousethelargerrigidpipe.
Theplacementofthecofferdamisalsoanimportantconcern.Thesediversionstructuresshouldbe
builtonastraightsectionofthestreamratherthanabend.Alsolookforplaceswherethechannelform
haswelldefinedbanksthatrisefromthestreambedquickly.Thesechannelscontainwaterbetter
becausethepotentialchannelvolumeishigher.Ifthediversionisplacedinaplacewherethechannel
bediswideandflat,thewaterspreadsoveralargerarearequiringmoregravelbagstopreventflanking
ofthediversion.Theareatosealalsobecomesmuchlargerandthereismorepotentialforleakage.
Narroweranddeeperdiversionsalsoseemtodrainbetterastheydevelopmorepressurehead.
Sometimesthereisntaperfectlocationanditisbettertobuilditwhereyoucanthanmakethe
diversionlongerinsearchofabetterchannelform.
ForstandardspecificationsforconstructionofstreamdiversionsseetheCaltransspecificationscitedin
theliteraturereview.Belowaresometipsondiversionsthatwillmaketheconstructionand
maintenanceofthestructureeasier.
1. Theprojectengineercanhelpdeterminethebestpipesizesforyourdiversion.Thiswillinvolvecalculatingtheflowrateofthestreamandtranslatingittothecapacityofthepipetocarry
water.Thiscangettrickywhencomparing
flowinthechannelwithflowinthepipes
becausetheflowdynamicsare
substantiallydifferentinthechanneland
pipe.Generally,pipescantransportmore
waterperminuteatagivencross
sectionalareathananaturalchannel.
2. Makesuretohaveplentyofmaterialsonsitewhenthediversionistobebuilt.Itis
besttoordermorematerialsthanmight
beanticipated.Diversionsrequirealotof
materialsbecauseasthedamimpoundswater,thevolumeandelevationofwaterupstream
buildsupandcanflowaroundacofferdamthatistoosmall.
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3. Stockpilegravelbagsnexttowherethecofferdamwillbeconstructed.Placementofthebagshastohappenquickly,soyouneedyourmaterialscloseby.
4. Whenattachingplasticsheetingtocorrugatedpipe,besuretohavethewirelyinginthesamegrooveofthecorrugatedpipeallthewayaroundthepipe.Thiswillformagoodsealonthe
inlet.Oncetheplasticismountedtothepipes,cutoutanXpatternintheplasticonthepipe
openingsandfoldtheplasticflapsinsidethepipe.Thepipesarenowreadytopasswater.
5. Itisagoodideatohaveacrewof5to6peopleonsiteduringconstruction.Dependingonthewidthofthestreammorepeoplemaybeneeded.
6. Whenthewaterbeginstoflowontotheplastic,itwillcompresstheplasticontothechannelbedandformthemainsealofthestructureacrossthechannelbed.Itisatthisvitaljunction,
whenflowisfirstbeingcapturedandkeptfromthechannel,whenfishmayswimupandunder
theplasticwhileitisbeingcompressedonthechannelbed.Thisislikelyaresponsetotherapid
lossofwaterinthechannel.Anyfishthatmaynothavebeenmovedpriortotheinstallation
mayraceupstreaminresponse.Thesmallerfishcaneasilygetcrushedinhere.Loweringthe
plasticslowlywhilewatchingforfish,andusingaseinebehindtheplastictomakesurefishcannotswimundertheplasticarerecommended.
7. Whilethewaterbeginstobecapturedbythediversion,besuretoletthediversionleak,andfairlysubstantiallyatfirst.Itisimportanttohavesomewaterflowinginthestreamchannelto
sustainanyfishintheprojectreachuntiltheycanbeisolatedinpoolsandrelocated.Asfishare
isolatedintothepools,begintodivertmoreofthewater.Oncefinishedmovingfish,thecoffer
damcanbequicklysealed.
8. Inmostcaseswhenwaterisdiverted,asecondcofferdamisconstructedatthedownstreamextentoftheprojectsite.Thisdamisintendedtokeepturbidwaterintheworksitefrom
flowingintothelivestreamdownstream.Evenwhenastreamreachhasbeendewatered,itis
oftenthecasethattherewillstillbe
watercollectingatthedownstream
endoftheworkzone.Thisisusuallya
resultofleakingdiversions,water
upwellingfromthechannelbed(very
commoninhighergradientreaches),
andwaterbroughttothesurfaceby
constructionactivities.Downstream
damsalsopreventfishfromre
enteringtheworkzoneandcanhold
backcleanwaterthatmaybackflow
intotheconstructionzone.Backflow
iscommoninlowgradientreaches.
Inmostcases,thesedamsareconstructedwithsandbagsfilledwithwashedsand,ratherthan
gravel,andwithoutplasticsheeting.Strawbalesmayalsoworktoblockflowandfilter
sediment.Inmostcases,theseweirsarenotsealedbecausepumpswillmovetheturbidwater
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outofthechannelforfiltering.Thedamsaremainlyalastlineofdefenseinthecaseofa
diversionfailureandareabarriertofish.Thephotoatrightshowsadownstreamcofferdam
holdingbackturbidwater.
9. Oncethediversionisupandrunning,itneedstobemaintainedandmonitored.Thisisbecausecofferdamsrarelyformadryseal.Someleakageispredictable.Onestrategyformanagingleaks
fromadiversionistodigashallow(1to3foot)holeinthechannelabout15feetdownstream
ofthediversion.Thishole,orsump,will
capturetheleakagebothfromthesurface
flowandshallowgroundwaterflow.Plan
thelocationofthediversionsoasumpcan
beinstalledupstreamofconstruction
activities.Thesumpcanactuallycapturethe
leakedwaterwhileitisclean,sowatercan
simplybepumpedbackupstreamofthe
diversion.Thiscansubstantiallyreducethe
volumeofturbidwaterthatneedshandling
downstream.Thephotoatrightshowsa
sumpcapturingleakagetobepumped
upstream.
10.Sometimesduringconstruction,thewaterdiversionmaybeaccidentallydamaged.Whenthishappens,thediversionneedstobesealedquicklybeforethewaterfromthepipesoverwhelms
thepumpatthedownstreamend.Withsomeadvancedplanning,thiscanbedonequickly.
First,beingpreparedinadvancewithmaterialseasilyathandiscritical.Preparebyhavingpre
cutpiecesofplasticsheetingmeasuringapproximately3feetwideby4feetlong,stagednextto
thediversion.Alsohavebalingwire,wirecutters,andpliers.Intheeventofarupture,wraptheplasticsheetingaroundthepipeseveraltimesatthepointofleakage.Then,wrapthewireover
theplasticmakingsurethewireisinthesamegrooveofthecorrugatedpipe.Pullthewiretight
andtwist.Dothisbothupstreamanddownstreamoftheruptureinthepipe.Thiscansealthe
leakandcanbedoneveryquickly.
Agoodtimetotrypracticingthistechniqueisduringconstructionofthediversion.Wherever
twolengthsofpipearejoined,usuallywithajunctionsleeve,youcandotheplasticwrap
techniquetogetabetterseal.Itisgoodtodothisanywayandbyplanningaheadtherewillbe
peopleonsitethathavedonethisbeforeandcanworkquickly.
11. Duringconstruction,itiscommontopumpturbidwateroutoftheworkareatokeepitfromflowingdownstream.Therearenumerousmethodsformanagingsedimentladenwater,and
theoptionyouchoosewillbebasedonthevolumeofwaterandsedimenttobemoved,the
typesandsizesofsediments,siteconstraints,thelengthoftimethepumpswillberunning,and
therelativeimpactstheremovalofwaterhasonsurfaceflow.
Onsmallerstreamsduringthesummer,flowisgenerallylowanditisfairlyeasytopumpthe
watertoanuplandarea.Choosealocationwherewaterisdistributedoverawideareatoeither
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percolateintothesoil,orflowthroughsufficientvegetationtofilteroutthesedimentbeforeit
flowsbackintothestream.Forprojectslastingmanydaysitiscommontomovethedischarge
pointsperiodicallybecausesoilgetssaturatedeasilyandthepercolationratesdecreaseover
time.Siltfencingcanalsobeeffectiveongentleslopestoensurethatturbidwaterdoesnotflow
backintothestream.
Becausetherearesomanyconsiderationsandmethodsforcontrollingsedimentladenwater,
projectmanagersshouldrefertothepublicationFieldGuidetoConstructionSiteDewatering;
AppendixBpublishedbyCaltrans.
12.Justascarewasappliedinsettingupthediversion,caremustalsobetakenwhentakingthediversiondownandlettingthecreekflow.Thebiggestpotentialimpactherelieswiththe
channelbedsubstrateconditionscreatedbytheproject.Channeldisruptionoftenleavesfine
sedimentonthetopofthechannelbed.Releasingwaterintothismaterialcancausethis
sedimenttoflowdownstreaminaturbidplume.
Thereareseveralwaysthatthisimpactcanbereduced.Onemethodinvolvesactuallyapplyinga
layerofsmoothcobbleandgraveltothechannelbedpriortotakingthediversiondown.Thisgravelencapsulatesthefinesediments
underneathandpreventsplumesofturbid
water.Anothermethodistocleanthe
channelinoneoftwoways.Oneistousea
pumpwithcleanwatertopowerahoseand
nozzlethatisusedtowashfinesedimentsto
thedownstreamofthediversionwhereitcan
bepumpedoutofthechannel.Aless
technicalwayistoallowpulsesofcleanwater
toflowfromtheupstreamcofferdam.Thepulsesofflowcollectsedimentwhereitis
pumpedoutofthechannelfromthe
downstreamcofferdam.
13.Oncewaterisnolongerbeingdivertedintothepipes,thepipesshouldbeemptiedimmediately.Thisisbecausefishareofteninthepipesandtheremainingwaterinthepipescangetheatedor
depletedofoxygeninashorttime.Toemptythepipes,startattheupstreamendofeachpipe
andliftitaboveyourhead.Then,walkyourhandsdownthepipesothewaterisallforcedout
towardthedownstreamend(seephotoatleft).
14.Forhandlingturbidwater,pumpoptionsincludeelectricpumpsandgaspoweredpumps.Bothcomeindifferentsizestomeettheneedsofanyproject.Ifusingagaspump,itshouldbeset
insideacontainmentvesseltopreventfuelspillsfromenteringthewater.Electricpumpsare
usuallyrunbyagenerator,whichcanbelocatedoutsideofthechannelarea,reducingthe
possibilityofafueldischargeintothechannel.Sincetheyaregenerallyonespeedpumps,the
pumpingratecannotbemanipulatedlikeagaspumpwithathrottlelever.Incaseswherethe
pumpingneedstobemoderatedtoavoidrunningoutofwater,afloatvalvecanbeusedtoturn
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thepumponandoff.Mostelectricpumpshavetheirintakesonthebottom.Thishelpsthem
workinshallowerwaterthanagaspump.However,theydontworkwellwhenplacedupright
directlyonthechannelbed.Theywillneedtobesetatanangleinadeeperpoolsetonastand
toleavespaceenoughabovethechannelbedtoachievegoodintakevolume.
Ifthediversionandturbidwatermanagementsystemdependsonpumps,itisworththeextra
costtohaveabackuppumponsiteandready.Pumpscanbreakdownandwhentheydoitis
importanttohaveanotherreadytosetuponshortnotice.Itcanbeveryexpensivetostopwork
togetanotherpumpasyouarestillpayingfortheequipmentonsitetositidle.Pumpsalsohave
maintenanceneeds,sotheseneedtobeconsidered.Ifthediversionisbeingmanagedbythe
contractor,talkwithyourcontractorabouthavingbackupequipmentready.
15.Surfacediversionsareusuallybuiltduringthedaywhenriparianvegetationisdrawinginwaterforgrowth.Atnight,whenphotosynthesisstops,theplantsarenottakinginwater.Theresultis
thatwaterlevelsinmoststreamswillriseovernight.Besurethediversionhassufficientcapacity
toaccommodatethisextrawater.
16.Alwaysmakesurethereisanadequatebudgetforwatermanagement.CaseStudy:Dewateringusingatemporarywell.
Whileworkingonafishpassageprojecton
StennerCreek,thesurfacediversionalone
wasnotsufficienttodewatertheworksite.
Theissueonthissitewasthatitwasinan
upwellingzonewheregroundwaterwas
pushedtothesurface.Whileitisnormalto
havesubsurfaceflowsbelowthechannel
bed,itisquiteanotherissueifthesubsurfaceflowistriplethevolumeof
surfaceflow.Tokeepthesitefreeofflow,
anothermethodwasneeded.
Thesolutionwastouseasubmerged
slottedwellpipetopumpthesubsurface
flowoutoftheworksite.Anexcavatorwasusedtodigaholeapproximately7feetdeep.Inthehole
wasplacedan8inchPVCpipewithslotscutinittoletwaterflowintothepipe.Thechannelbedwasre
filledwiththepipeembeddedinthechannelbed.Asubmersiblepumpwasplacedintothepipeto
pumpthewaterdown.
Oneofthebenefitsofusingthistechniqueisthatthewaterbeingpumpedwasclean.Therefore,we
coulddischargeitdirectlyintothechanneldownstreamoftheprojectreach.Whendischargingwater
backintothestreambed,setupsomewayofdissipatingtheenergyofthedischargesoitdoesntcreate
turbiditybydisturbingthechannelbed.Placingthehoseinabasinmadeoflargercobbleworkswell.
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Building Habitat Structures
RockStructures
Manyriparianhabitatrestorationprojectsinvolvebuildingrockstructures.Theseprojectscanbe
challengingandatestofyourpatience,aswellasyourexcavatoroperatorspatience.Gettingthese
structuresconstructedproperlythefirsttimesavesalotoftimeandmoney.Belowareafewtipsto
helpmakeyourrockstructureseasiertobuildandlongerlastinginthestream.
1. Themostimportantpartofarockstructureis,ofcourse,therock.Notallrocksarecreated
equallyhowever,andyouwanttousethe
strongestrocksavailable.InCalifornia,thisis
usuallygranitebecauseitisveryhardand
heavy.Itiscapableofholdingsteelcables
permanentlyanditsangularshapemakesthem
wellsuitedtoinstreamstructures.Softerrocks,
suchasserpentine,arebrittleandfracture
easily,makingtheminferiorforinstreamwork
(seephotoatright,cabledrockfailure).
Caltranshasstandardspecificationsforrock
durabilityanddensity.
2. Whenbuildingrockstructures,thebestrocksarethosewithangularshapesandlargeflatfaces.Rockstructuresgetmuchoftheirstrengthfromadjacentrocksthathavealotofrockfaceto
rockfacecontact.Boulderswithroundershapestendtorollandnothavegoodcontactwith
adjacentrocks.
3. Nothingismorefrustratingthanfinishingarockweirandn