restoration field guide - a user-friendly guide for restoration techniques in riparian habitats

8/8/2019 Restoration Field Guide - A User-Friendly Guide for Restoration Techniques in Riparian Habitats

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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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CHOOSINGPLANTS............................................................................................................................... ........................46

TipsforPlantPalettes.........................................................................................................................................46

PLANNINGFORIRRIGATION............................................................................................................................... .............47

PLANTINGMETHODS............................................................................................................................... .....................50

PROJECTMONITORING.....................................................................................................................................54

CONCLUSION....................................................................................................................................................55


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1

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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10

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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21

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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22

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

restoration field guide - a user-friendly guide for restoration techniques in riparian habitats

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