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101-Staff Report.pdf
PUBLICWORKS DEPARTMENT CITY HALL 1010300TORRE AVENUE • CUPERTINO, CA 95014-3255 TELEPHONE: (408)777-3354www.cupertino.org CITYCOUNCILSTAFFREPORT Meeting:May 17, 2011 Subject th ReportontheGolfCourseIrrigationUpgrade–SCCPPhaseIITrail& 8HoleConflict MitigationAlternatives. Recommendation ReceiveReport. Discussion InJuneof2010,CouncilapprovedtheCIPforfiscalyear2010/2011.TheFY10/11CIP includeda$550,000projecttoupgradethe40yearoldirrigationsystematthegolfcourse.The existingirrigationsystemistheoriginalthatwasinstalledbytheformerprivateownerinthe early1960s.Overtheyears,thelines,jointsandsprinklerheadshavedeterioratedandcracked tosuchanextentthatleaksandoperationalrepairsarefrequentandexpensive.Withtherecent largeincreasesinthecostofwater,ithasalsobecomeimperativetomakethesystemmore efficient. Thegolfcoursewasoriginallyirrigatedwithwatertakenfromawell,constructedinthe1940s, locatedatthebackoftheconcessionstandinBlackberryFarm.Thewaterwaspumped upstreamtoalargesteelholdingtankandthenpumpedbackdowntothegolfcourseirrigation lines.In2002,thetankbottomandsidewallwerediscoveredtohaverustedoutbeyondrepair anditwastakenoutofservice.IrrigationofthegolfcoursewasthenswitchedovertotheCity’s potablewater systemfromSanJoseWaterCompany.DuringconstructionofSCCPPhaseI,the tankwasremovedandrecycled. BeforeconstructionofSCCPPhaseI,thegolfcoursepondswerefeddirectlyfroman“intake gallery”onthebankofStevensCreek,nearthecurrenteducationalaccesspoint.Thegallery waspositionednearthebottomofthecreekbutduringlowcreekflowinthesummermonths, verylittleandsometimesnowaterflowedintotheponds.Thisirregularandlowflowofwater contributedtothechokinggrowthofcattailsintheponds.Thealternativedomesticwatersource wasalsoconsideredtooexpensivetouseasawatersourceforthepondsandverylittlewasever used.Thepondswillcontinuetodeteriorateuntiltheyarecleanedoutanda newwatersourceis provided. Whenthegolfcourseirrigationprojectwasunderconsideration,stafffromParksandRecreation andPublicWorks begantoconsiderthe possibility ofreactivatingthewelland usingthewaterto filltheponds,withthepotentialofusingthatpondwatertoirrigatethegolfcourse.TheCityis stillhaswaterrightstothewellwater,asdeterminedbytheformerCityAttorney.Awaterline wasinstalledinPhaseIbetweenthewellandtheupperpondinanticipationofonedayusingthe wellwatertofillthe ponds. th Theproximityconflictbetweenthe 8holeandthetrailforPhaseIIismademoredifficultby thelocationofthelowerpond,reducingthealternativesforadditionalseparation.Parks& Recreationstaffhavelonghadthedesiretocleanupthelowerpondandreconfigureittoabetter shapeandsize.TheGolfCourseIrrigationUpgradeprojectwasseenasanidealopportunityto notonlyreconfigurethepondforirrigationpurposes,buttoalsochangeitsshapetoallowmore th space betweenthe 8 holeandthetrail. Unfortunately,theGolfCourseIrrigationUpgradeprojectisnotsufficientlyfundedto accomplishallofthegoalsstatedabove.Theoriginal$550,000budgetwasestablishedto replacethemainandlateralirrigationlines,providenewsprinklerheadsandautomated controllers,cleanouttheponds,andreactivatethewelltofilltheponds.Forthislimitedscope ofwork,the budgetis sufficient. FollowingCouncil’sdirectiontoinvestigatealternativestomitigatethepotentialconflictswith th the 8holeandthetrail,staffconducteda“designcharrette”withkeydesignmembersofboth thePhaseIIprojectandtheIrrigationproject.Thatalldayeffortproducedseveralgolfcourse reconfigurationalternativesandcostestimatesthataddressall ofthegoalslisted below: th ·Reduce oreliminatetheimpact ofthetraillocation on the 8 hole ·Replacethe outdatedandinefficientirrigationlines ·Fillthe ponds withlessexpensive naturalwaterratherthanexpensive domesticwater ·Rehabilitatethe ponds andcreate native habitat ·Usethe ponds asanirrigationreservoirandlinethemtoreducewaterleakage ·Substantiallyreducetheannualwater billforirrigation ·Preventchlorinatedwaterfrom potentiallyenteringintoStevensCreek Thedesignteamidentifiedthreeconceptsthataccomplishallofthegoalslistedabove (AttachmentsC-1,C-2andC-3).Theyrangeincostbetween$1.1Mand$1.25M,ofwhichthe Cityhasalready budgeted $550K. The budget shortfallrangesbetween $550Kand $700K. Giventhattheshortfallisasubstantialamountofadditionalmoney,stafflookedintothe possibilitiesofbreakingtheprojectintobasicelementsrelativetopotentialsavingsinannual operationalexpenses. Thecostofwateringthegolfcoursethispastyearwasabout$60,000.In2002,whenthe irrigationwatersourcewasswitchedovertoSanJoseWater,theannualcostwasabout$30,000, because40%ofthewaterwassuppliedbythewellandtheother60%camefromSanJose Water,whichhasgenerallycosttwiceasmuchaswellwater.In 2001,relyingalmostentirely on wellwater,we paid only$19,000toirrigatethegolfcourse. Thecurrentirrigationupgradeproject,budgetedat$550,000,willreplacealltheirrigationlines andmayreducetheannualexpenseofwaterbyabout15%bypreventingleaksandinefficient wateringcycles.Itwillalsoreactivatethewellheadandallowwaterbackintothetwoexisting ponds, butit does notincludethefunds necessaryto preventthe ponds fromleaking. Substantiallyhighersavingsinwatercostscanbeachievedbychangingthesourcefrom domesticwaterbacktowellwater.Thischangemightresultinaninitial55%savings,orabout $35,000.Thecostofthewellwaterisnotlikelytobesubjecttodramaticannualincreaseslike thoseforecastfor domesticwater. Irrigatingthegolfcourserequiresalittlemorethan16milliongallonsofwaterperyear. st Approximately90% ofthatwaterisconsumedduringthesixmonthsofMay 1throughOctober 31st. Thefollowingalternativesprovideoutlinescopesofworkandbudgetshortfallinformationfor consideration.ItshouldbenotedthatAlternativesAandBwillcontinuetorelyentirelyupon domesticwaterfromSanJoseWaterCompanyforthegolfcourseirrigationrequirements. Alternative A Thisprojectiscurrentlyscopedandunderway.Itincludesthereactivationoftheexistingwell head,therehabilitationoftheponds,andthereplacementoftheirrigationmainlineandthe laterals,sprinklerheadsandcontrollers.Thewellwaterwillbepumpedtotheupperpondand allowedtorundowntothelowerpond.Thelowerpondwillnolongeroverflowintothecreek, butshouldthathappeninadvertently,thewaterwillnothaveanypotentialtocontaminatethe creekorharmthefish.Itiscurrentlybudgetedat$550,000andscheduledforcompletioninthe fall of 2012.Shortfall:none Alternative B Thisalternativewouldincludereactivatingthewellhead,cleaningtheponds,replacingthe irrigationmainlineandlaterals,sprinklerheadsandcontrollers,andmakingminoradjustments tothe8thholeteebox,fairway,andgreen.Thelowerpondwouldbereconfiguredtoallowthe th entire 8holetomovefurtherawayfromtheanticipatedtrailalignment.Thelowerpondwould bepreventedfromoverflowingintothecreekasinAlternativeA,butwouldneedadditional funding ofabout $75,000fora projecttotal of $625,000.Shortfall: $75,000 AlternativeC-1 Thisalternativeisfundamentallydifferentfromtheprevioustwointhattheupperexistingpond wouldbeconvertedtoabio-swaleandthelowerexistingpondwouldbecompletely reconfiguredintoasingle350,000gallonreservoirlake,fedbythewellhead.Thereservoirlake wouldthensupplyregularirrigationwaterthroughaseriesofpumpsandsupplylinestoanew irrigationsystemofmains,laterals,sprinklerheadsandautomatedcontrollers.Thepotable watersystemwouldremainconnectedasabackupforemergenciesorshorttermlowflow th conditions.Inthisalternative,the 8holewouldbemovedalittlebitfurtherawayfromthe PhaseIItrailalignment.SeeAttachment.Itis projectedtocost $1,100,000.Shortfall: $550,000 AlternativeC-2 ThisalternativeisdifferentfromC-1inthatthelowerlakewouldbereconfiguredintotwo th separatelakes,withoneofthelakesbeinglocatedbetweenare-located 8holeandthe anticipatedtrailalignment.Thelakeswouldtogetherprovidethereservoircapacityforthe irrigationsystemandwouldbeconnectedtoeachotherbyanundergroundpipe.See Attachment.Itis projectedtocost $1,175,000.Shortfall: $625,000 AlternativeC-3 Thistwolakealternativeisdifferentfrom,andmoreexpensivethan,C-2inthatholes5,6,7, and8arereconfiguredandplayedinthereversedirectionwithrebuiltteesandgreensthatneed improvementnow.Thereverseplayofhole#5reducestheneedforballprotectiononornear thebridgeandalsoprovidesgoodseparationfromthetrail.Thelakeconfigurationisalso deemedtobealittlemorechallenging.SeeAttachment.Itisprojectedtocostabout$1,250,000. Shortfall: $700,000 SustainabilityImpact AnyoneoftheGolfCourseIrrigationUpgradealternativeswillfullysupporttheCity’s sustainabilitygoals. ____________________________________ Preparedby:TerryW.Greene,CityArchitect Reviewedby: TimmBorden,Director ofPublicWorks MarkLinder,DirectorofParksandRecreation ApprovedforSubmissionby:DavidW.Knapp,CityManager Attachments:AlternativesC-1,C-2,andC-3