Western Pacific’s Willow Glen Trestle/the structure Century. · Commission to Resume WP...

WesternPacific’sWillowGlenTrestle/thestructureOverview.Thisanalysisconsidersthetrestlestructureinthecontextofitstimesanditsregion.Aseparatesectionconsiderthetrestleinthecontextoflocalhistory.Also,commentsareofferedontheanalysiscontainedintheDEIR“ThreeCreeksTralPedestrianBridge”January,2015.Thetrestleisauniqueregionalresourceexemplifyingrailroadconstructionmethodsofearly20thCentury.

CaliforniaRegisterofHistoricalResourcesEligibilityCriteria3Embodiesthedistinctivecharacteristicsoftype,period,region,ormethodofconstructionorrepresentstheworkofamasterorpossesseshighartisticvalue.CityofSanJoseHistoricLandmarkDesignationCriteria(subset)Itsembodimentofdistinguishingcharacteristicsofanarchitecturaltypeorspecimen.Itsembodimentofelementsorarchitecturalorengineeringdesign,detail,materials,orcraftsmanshipthatrepresentasignificantarchitecturalinnovationorthatisunique.

TheWillowGlenTrestleoverLosGatosCreekontheWesternPacific’sBeltlinefromNilestoWestSanJosewasthefinalcreekcrossingintothehighlydesirableindustrialdistrictofSanJoseregion.1Thetrestleispilebentconstructionandabout25ftabovethecurrentstreambedheightandroughly210.5feetlong.2Accordingtothesameconsultant,thebridgeshowsevidenceofreceivingroutinemaintenanceduringitsrailroadoperationyears(1922‐1998).Therearetwotypesofwoodentrestles:pilebentandwoodframedtrestle.Thepilebenttrestleconsistsofpilesthataredrivenintotheground.Groupingsofpilesarrangedinalinearecappedtogethertoformabent.Thepilesaretreetrunks,shearedofbranches.Becausetreesareused,theupperlimitinheightis25to30feetandseldomusedforheightsthistall.3Piletrestlesareusedwheregroundissoftormaybecoveredwithwater;alsowherethedistancefromthegroundtothe1“Offerof10acresmadetorailroad.WesternPacificVicePresidentsaysCompanydeterminedtoreachindustries.SaysAttitudeofWillowGlenispurelydestruction—hasnofaithinresults.““RailBoardaskedtoOrderUnionStation”“RailroadCommissiontoResumeWPMatter.”SanJoseMercuryHerald.1917Sep282ThreeCreeksTrailRailroadTrestleatLosGatosCreek.CH2MHill.October8,2012.3Foster,WolcottCronk.Atreatiseonwoodentrestlebridgesandtheirconcretesubstitutes.1913.Page6.

railisnotgreat.4Pilebentsbetween10and20feetshouldhave1crossstructure.5ThisisliketheWillowGlenTrestle.

Thesecondkindofwoodentrestleisaframedbent.Thesetrestleshavefoundationsandthewoodenmembersaremilledintosquarededges.Theycanbebuiltintotallerstructures.ThisisnottheWillowGlenTrestle.6

AnalysisofDEIRoncriteria3(California)TheLosGatosCreekBridgerepresentsanimportantexamplewithinitscontextofbuildingpracticesataparticulartimeinhistory.Itisbothatypicalandatypicaltypeofstructure.Thestructurefollowsthegeneraldesignofpilebenttrestlesasdescribedinpublicationsofthetimeperiod.However,itisatypicalinthefollowingways:‐‐Ithasavaryingnumberofpilingsineachbent,with5,6,7or8pilings.Thoughreferenceismadeinthehistoricreportthatthebridgeisa“6‐pile”railroadtrestle4Foster.Page7.5Foster.Page10.6Foster.Page52.

suggestingtherepairsdetractedfromthestructure.However,noattemptwasmadetoexplaintheatypicalityofthe5‐pilingbents(Bent3andBent14)thathavefewerthan6pilesandnopilesfromrepairs.‐‐Thetrestle’sheightisatypicalforwoodenpilebenttrestlesaccordingtoengineeringbooksofthetimeperiod.7Twenty‐fivefeetwasattheupperlimitforpilebentstructuresduringthistimeperiod.Pilebentsrequiresingletreetrunks.Availabilityofsuchtallpiecesoftimberwerelimitedinthebestoftimes.Further,thistrestlewasbuiltimmediatelyafterWorldWarIandmanyutilitiesandrailroadsneededthesetallpiecestodoconstructionandmaintenancedeferredbythenationalizationoftherailroadsduringthewarandthelimitationsimposedbywar.TheselectionofthistypeofstructureinsteadofaframedtrestleisnotusualaccordingtoFoster.Constructingafoundationinthecreekbedwouldhavebeeneasy.ThereisalongextendeddryperiodandthecreekflowwascontrolledbymultipledamsonthetributariestoLosGatosCreek.8LittlewaterflowedbeyondtheKirkIrrigationditchdiversionupstreamofthistrestle.Further,therewasnourgency—otherconstructiononthe“Beltline”didnotfinishuntil1922.Thetrestlecouldhavebeenbuiltasaframedtrestle.Instead,thedecisionwasmadetobuilditasapiledtrestleattheupperendofrecommendedheightsandavailabletimber.‐‐ANationalParkServiceWhitepaperprovidesguidanceabout“EvaluatingCommonResources”andsuggestsseparatingintosubtypes.9TheconsultantseparatesthewoodentrestlesintopilebentandframedclaimingthatRichardCookauthorofthe1987bookTheBeautyofRailroadBridgescameupwiththisdistinction.However,thisdistinctionwasmadeclearintheearlyeditions(1913andearlier)ofWolcottCronkFoster’sATreatiseofWoodTrestleBridges.However,moreappropriately,theanalysisshouldbebasedontheuniquenessandrarityoftall(25ft)andlong(210ft)pilebenttrestles.‐‐Afurthersubdivisioncouldbetimeperiodofconstructionasisdonewithbuildings.ThisbridgewasconstructedshortlyafterWorldWarI,justaftertheFederalGovernmentstoppedoperatingthetrains.Allrailroadsscrambledtomakereportstoroadsandrollingstockthathadbeenplaced“onhold”whiletheFederalgovernmentoperatedtherailroads.Significantdifferencesinconstructionandavailabilityofmaterialsexistbetweenthisimmediatepost‐wartimeperiodandothertimeperiods.‐‐TheinventoriesusedbytheconsultanttoarguethatthislongandtallpilebentbridgeisubiquitouswerefromtheSacramentoregionofSouthernPacificandlimitedtoidentifyingwoodtrestlesbyopendeckandballastdeck.Thebridgeswerenotcategorizedbyhowtheengineersofthehistorictimeperiodcategorized:7Foster.Ibid.8HistoryofDamsofLosGatosCreekWatershed.www.scvwd.org.AccessedMarch15,2015.9NPS.2009.www.nps.gov/nr/...3.../NCSHPO_Common_Property_Types.pdf

pilebentandframedtrestle.Noanalysisismadebyheightandlength.Furtherthenationalsurveydoesnotmakethesedistinctionsbysubcategoryeither.Giventhattheconsultantacknowledgestheimportanceofusingsub‐types,theseareinappropriateinventorieswithwhichtodismissthesubjecttrestleandcallit“ubiquitous.”10‐‐Thetrestleisalong‐spanofover210ft.AninventoryofSantaClaraCountytrestleswasmade.Therearefewall‐woodenpilebenttrestlesoverallandfewthistall(25ft),andlongerthan59ft.Bythenumbers,whatremains:1woodenpilebenttall(≥25ft)andlong(over200ft)trestleisownedbySanJose subjectWPRRbridgeoverLosGatosCreek2woodenpilebenttall(≥25ft)andlong(over50ft)trestlesareownedbyUPRR oneisinSanJoseonabandonedWPPRline oneisatSanBenitoCountylineonHollisterbranch(southofGilroy)1woodenpilebentnottall(<25ft)andlong(over50ft)trestle northofAlvisoinSanFranciscoBay.Allothersimilarall‐woodenpilebenttrestleshavebeendemolished,arescheduledfordemolishingorchangedtoI‐beamsorconcretefootings.Nootherall‐woodentrestlesareknowninSantaClaraCounty;however,afewshortspansoftwobentsoverculvertsandchannelizedsmallcreeksmightstillbeall‐woodenpilebentbutwerenotidentifiedbythisauthor’sfieldteamduetoviewsblockedbyinaccessiblelocations.NotablyallbuttwooftheWesternPacific’strestlesofanysizeordesigninSantaClaraCountyhavebeenorwillbedemolished.IfthissubjecttrestleatLosGatosCreekisremoved,onlyONEWesternPacifictrestlewillremaininSantaClaraCounty(atCoyoteCreek)Inscopingquestions,CathyRubinasked“ArethereothersimilarbridgeswithinSanJosethatwecouldvisitthatwouldtellthesamestory?Aretheyinwalkingdistance?Bikingdistance?...getincarsanddrivewhoknowshowfar?..tellthesamestory?”

Cathy,atthiswritingthereare4WesternPacifictrestlesofanykindinSantaClaraCounty.Twoarescheduledtobedemolished;thereisnothingthatcanbedonetosavethem.Thissubjecttrestleisatriskofdemolishing.ThereisoneothertrestleatCoyoteCreeknearStoryRoadanditisownedbytheUnionPacificontheabandonedline.Notracksleadtoit;itisatrisk.NoothertrestlestelltheWesternPacificstoryinSantaClaraCounty;theyareallgone.

10Interestingly,bridgeinventoriesarenotrequiredbytheFederalRailroadAdministrationortheCaliforniagoverningbodies,unliketheCaliforniaStateHighwayCommission.RecentFederallegislationwillchangethisasaresultofconcernsabouttheshipmentofoilcrude.

Ifyouwanttoviewanothernicetallandlongall‐woodentrestle,youcandrivesouthofGilroytotheUnionPacific’sactiveHollisterline.ItcrossesthePajaroRiver.ItcanbeviewedfromHighway25’sshoulder,buttakebinoculars.Thecrossingisblockedbyprivateproperty.Therearenoothertallorlongwoodentrestlesofanyconstructiontype(pile‐bentorframedtrestle)designinSantaClaraCounty.Ifyouwishtoviewalongtrestlethatisnottall,youcantakeacanoetotheDonEdwardsNationalwildlifepreserveinSanFranciscoBay.Oryoumayviewthetrestlewithbinocularsfromthetrailsonthelevees.ThistrestlewasbuiltfortheSouthernPacificanddoesnottellthesamestory.ThereareafewtrestleswithconcreteconstructionorI‐beamconstruction.

TheLosGatosCreektrestleisuniqueinSantaClaraCounty.ItisownedbytheCityofSanJoseandcouldbeprotected.ItrepresentsoneofTHREEremainingsimilartrestlebridgesintheCountyofSantaClarawheremanywoodenpilebenttrestleswereonceinserviceandnowhaveallbut3havebeenorwillberemoved.ThisqualifiesthetrestleforhistoricstandingunderCityofSanJose—itembodiesaparticulartype—atall(≥25ft),long(>210ft)pilebentwoodentrestleanditisverynearlyunique.ItisthelastoneoftwointheCityofSanJoseandthecityalreadyownsit,anditispubliclyaccessibleincontext!

IntheWrit,FriendsofWillowGlenTrestle,SusanLandrystatethesubjectbridgeistheonlytimbertrestlestillinplaceonWesternPacificlineinWillowGlen.Moreproperly,itistheonlyonethatcouldbesaved.TheotheroneattheGuadalupeRiverisdestinedforremovalforaSantaClaraValleyWaterDistrictfloodcontrolproject.

TheDEIRconsultantusesCook’sbeautiful“coffeetable”picturebookaboutRailroadBridgestodemonstratethatonlyframedtrestlebridgesweresufficientlyinterestingtobeincludedinthebook.Fromthisdecisiononaesthetics,theDEIRconcludes“Thetallframedtrestles,forexample,achievedgreatengineeringsignificanceandincrediblebeauty.ThefarmorecommonpilebenttrestlesaresocommonastomakeitunlikelythatanyonewouldbesignificantunderNationalRegisterCriteriaC.“TheconsultantisarguingthataestheticsandengineeringdetermineCriteriaCratherthanthestyleofconstructionofthisparticularsubtype:all‐woodenpilebenttrestlethatistall(≥25ft)andlong(210ft).Historicstructuresdonothavetobepretty.ThelanguageofCriteriaC(NPS)andCriteria3(California)state:Embodiesthedistinctivecharacteristicsofatype,period,ormethodofconstruction:Thistrestleislong(210ft),tallforitstype(25ft),wooden,pilebenttrestlebuiltintheInterwaryears(completed1922).ConsideringthelocalSantaClaraCountyinventoryfortrestlesofthissubtype,thereareonlythreestanding(twowithuncertainstatusandoneattheSanBenitoCountyline).Allothershavebeendemolished,replaced,orareslatedforremoval.

BasedonthisinventoryofthissubtypeofwoodentrestleinSantaClaraCounty,anotheraspectoftheNPSWhitePaperonCommonStructuresapplies:“Propertytypesshouldbeconsideredcommonintermsoftheircurrentprevalence.“TheconsultantusesnationaldatafromFoster(1917)toindicateprevalenceofwoodentrestles(700,000ofanytype).Also,theconsultantestimatesfroma1999surveythatonly24,000timbertrestlesofanytyperemain—a97%decline.Woodentrestlesofanytypeareadisappearinghistoricresource.Theconsultantusesthemostrecentarchived(1970)bridgelogoftheSouthernPacific’sSacramentoBranchtoargueprevalenceoftimbertrestlesofanytype.Importantly,theNPSWhitePaperindicatesthatcurrentprevalenceshouldbeusedforcommonstructuresandthisinventoryis45yearsold!Further,thecoversaperiodwhenlumberingwasstillveryactiveinthemountains.Sincethen,manylineshavebeenabandoned.TheexaminedSacramentoDivisionregionisnotatallcomparabletoSantaClaraCountynormanypartsofCalifornia.Forexample,the1970’sreport’sareaisverywell‐watered—includingmightyriversandtheirtributariessuchastheSacramentoandAmericanRiversaswellastheBayDelta.ThereportalsocoversthemountainsoftheSierraNevada!ContrastthistoSantaClaraCountywherenotrainlinescurrentlyexistinthemountainsandthemightiestwatercoursesarecreeksthatflood.(Coyote,Guadalupe,LosGatos,Pajaro,andSanFrancisquitoCreek).Quiteclearly,theregionsarenotatallcomparableforestimatingprevalenceofbridgetypes.TheNPSWhitepaperfurtherdiscusses:“Someonce‐commonpropertytypeshavedwindledinnumberssignificantly,evensincetheintroductionoftoday’shistoricpreservationprograms.Forexample,one‐roomschools(evenderelictexamples)arenolongeracommonsightinmanyrurallandscapes.Once‐commonresourcesneedtobefullydescribed,includingadescriptionofpropertysubtypes.However,themorestringentintegrityrequirementsthatmayapplytotoday’scommonproperties,shouldnotapplytoanevaluationofexamplesofonce‐common,butvanishing,propertytypes.”Thereareveryfewtallandlongall‐woodenpile‐benttrestlesinSantaClaraCounty.Amoderninventory—ratherthanthe1970Sacramentoareainventory—mightprovidesimilarresultsinotherpartsofCalifornia.Nevertheless,itsuggeststhatlessstringentstandardsforintegrityshouldbeusedforthisstructurethanmightotherwisebeneededbecausetherearesofewleftofthissubtype.NPS.StateHistoricPreservationOfficesandlocaljurisdictionshavealonghistoryofdeclaringstructureshistoricwhentherearefewoftheirtyperemained.Examplesinclude:NewYork’sTenementMuseum—oneofthelasttenementsinManhatten,butonceverycommonandnotaestheticallypleasingnorgreatarchitecture;slavequartersonvariousfarmingproperties;oneroomschoolhouses;watertowers;barns.SanJosehasalonghistoryofpreservationaswell.Forexample,KBHomes

wasrequiredtopreservethewatertoweratDelMonte.BarrySwensonwasrequiredtosavethewaterpumpbuildingathisDuckettWaycondominiumstructure.HistoryispreservinganoldbarnonitscampusatKelleyPark.Asthesestructuresbecomerare,thecommonbecomesuncommonandpreservationisneededtocommunicatethestoryofthestructure.CanweexpectnolessfromtheCityofSanJoseforastructureitalreadyowns?TheconsultantdidnotdiscussaspectsofqualificationfortheNationalRegister/Howeveranalysisofintegrityishelpfulwhenconsideringahistoricresource.TheNationalParkServiceasksforananalysisofintegrityoflocation,design,setting,materials,workmanship,feeling,andassociation. Thetrestleisinitsoriginallocation. Thetrestlemaintainsitsoperationaldesignandcouldbereversedtooriginalcondition..Althoughbentshavebeenaddedasrepairs,itremainsasitwaswhenoperational.Safetyfenceshavebeeninstalledand,tiesandrailsremoved.Itcouldbereversedtoitsoriginalconstructioncondition. Thetrestleremainsinthecreekbedsetting.Visually,thealignmentoftherightofwayremains,althoughtracksandtieshavebeenremoved.Significanttreesthatareevidentinhistoricpicturesofthetrestleremainevident.HomesremainontheWillowGlensideandindustrialbuildingsremainontheMidtownside,includingthosethatwereextantatthetimeofconstruction. Materialsusedtomaintainthetrestlearesimilarasthosewhenitwasoriginallyconstructed.Replacementandadditionalpilesarecomposedoftreetrunks.Bentsandcrossframesaremadeofwoodandmilledtomatchtheoriginalstructure. Workmanshipremainsasitwasin1922.Thetrestlewasbuilttobeaworkhorsefortherailroadwithoutregardtoaesthetics.Thepileswerebuiltwithasymmetryineachbentandwithanunequalnumberofpilesconformingtothegeometryofthecreekbed.Yet,the13bentswereseparatedbyuniformdistance.StructuralcalculationsforthebridgedesignweredonewithoutbenefitofacalculatorandwithinthedepartmentofSanJosenativeW.H.Smitten(1873‐1953)whostartedasarodmanfortheSouthernPacificin1900andthenworkeduptostructuralengineer,priortoservingtheUSArmyCorpsofEngineersinWashingtonStateandinFranceduringWorldWarIfollowedbytakingtheheadBridgeEngineerjobatWesternPacificin1921.11SmittenremainedresponsibleforallWesternPacificbridgeengineeringuntilhisretirementin1947.Theuseofadditionalpilesandframesforrepairswascommonandcongruentwiththeoriginalnatureoftheinitialconstruction,ieadjustedfortheconditions.Constructionreflectedthebestjudgmentofonthegroundprofessionalswithmanyyearsofexperienceandnocalculatorandnocomputingcapabilityformodernmathematicalmodelingofstressloadsasdemonstratedinthefeasibilitystudy.Thealignmentwasnotusedafter1998andtherepairsreflecttheinthefieldmathematicalmodelingofthetime.

11Varioustradepublications,e.g.RailwayMaintenanceEngineer.Vol.17,No12.andRailwayEngineeringandMaintenance1947

Feeling.Thetrestleissurroundedbyalushriparianenvironment.Thosewhoviewhistoricphotosfromthe1950scannottellthedifferencebetweenthenandnow.Viewsalongthealignmentremainthesameexceptfortheremovaloftracks.Visitorsunderneaththetrestleexpressawe.Therearenovisualintrusions.Today’schildrenplayunderthebridgeinthecreekastheydidin1928.12 Association.Thetrestlecrossesthecreekwhichisinitsoriginal1922form,ienotchannelized.ItisconnectedtotheRightofWaywhichhasbeenmaintainedasopenspace.Thebuildingsandroadsinthearearemainthesame.ApersonwalkingoverthetrestleandalongtheRightofWayintoWillowGlenwillimmediatelyrecognizehowtheWesternPacificWillowGlenSpuralignmentatadiagonaldisruptedthelifeofWillowGlenresidentsandaffectedthepatternsofdevelopmentduringthedecadeof1920s.Thetrestlestilllinksanindustrialarea(Midtown)toa“highclass”residentialarea,WillowGlen.TheassociationtothestoryofthetrestleandtheWesternPacificisstrong.

12“GlenKiddiesMustWaitOneYearForSwim.”SanJoseNews.1928Sept.12.

Table.SantaClaraCountyinventoryofsimilarwoodenpilebenttrestlestructures:WesternPacific“Beltline”inSantaClaraCounty(photosfollow):

StillStanding­­FutureStatusUncertain1.SubjectbridgeLosGatosCreek.OwnedbyCityofSanJose.13bents.2.CoyoteCreeknearStoryRoad.PartofaCityofSanJose2008CoyoteCreekTrailmasterplanincludinghistoricinterpretation.OwnedbyUPRR.13DemolitionPlanned3.SilverCreeknearEggoandHighway101ontheBeltline.Lesshighthansubjectbridgeandmuchshorter.DemolitionplannedaspartoftailtrackconstructionforaVTA/BARTtailtrack.14Fourbents.4.GuadalupeRiversouthofAlmaStreetatFalconPlacewillbedemolishedaspartoftheGuadalupeRiverfloodcontrolproject.15Currentbridgeisshorterandwithfewerbentsthansubjectbridge.DemolishedAllWesternPacificBeltlinetrestlesofallsubtypesfromHwy101toAlamedaCountyhavebeendestroyedbyVTA/BARTPhaseIconstruction.16

SouthernPacific/CaltraintoMontereyCounty/UnionPacificMainline DemolitionPlanned 1.OverLosGatosCreeksouthofDIridonStation.17 Demolished. 2.AllwoodenpilebenttrestlesreplacedwithconcreteormetalIbars.1813CityofSanJose.CoyoteCreekTrailMasterPlan.2008.LowerSilverCreektoStoryRoad.14VTA/BARTPhaseIConstructionDocuments.http://www.vta.orgAccessed2014October30.15SantaClaraValleyWaterDistrictGuadalupeRiverFloodControlPlans,mapACPP_009.pdf.Dated6/6/2000.DownloadedfromSCVWDsecuredropboxon2013August27.16VTA/BARTConstructiondocuments.Ibid.17Caltrain.LosGatosCreekBridgeReplacementIS/MND.18Byinspection.

SouthernPacificCollegeParktoNilesviaJapantownandMilpitas. Demolished/Replaced 1.GuadalupeRivernearColemanAvenue19 2.OverCoyoteCreekatSchallenberger.ReplacedwithConcretepylons. Dateunknown.Byvisualinspection. 3.Nootherall‐woodenpilebenttrestleisknowntoAlamedaCountyline.SouthernPacificNewhallWYESantaClaratoAlviso(mainline) Existing 1.WoodenpilebenttrestlethroughDonEdwardsWildlifeReserve InSanFranciscoBay.Overwater. Nottallbutlong.Mightnotbeallwooden.(Hardtoinspectfully.) Demolished/Replaced 2.Nootherall‐woodenpilebenttrestleidentified.SouthernPacificHollisterBranch­GilroytoSanBenitoCounty Existing 1.OverPajaroRivernearBolsaRoad(Highway25).OwnedbyUPRR. AtSanBenitoCountyline. SouthernPacificLickBranch,HillsdaleBranch,NewAlmadenBranch,Camdenline,LosGatosLine,PacificCoastline,LosAltosLine,VasonaLine. Alltrestlesontheseabandonedlineshavebeenremovedordemolished.

19CityofSanJoseandSantaClaraValleyWaterDistrictjointmemodatedApril24,2012.http://www3.sanjoseca.gov/clerk/Agenda/20120424/20120424_0701.pdfAccessedMarch15.2015.

PhotosofSimilarAll‐WoodenTrestlesinSantaClaraCounty.1.WesternPacificOverLosGatosCreekinWillowGlen.SubjectBridge.AtRisk.20

2.WesternPacific.OverCoyoteCreek.NearStoryRoad.AtRisk.21

20Ames,Larry.2014.Ibid.21Byshed47.http://www.trainorders.com/discussion/read.php?11,794985AccessedMarch12,2015.

3.WesternPacificoverSilverCreekatEggoWay.DemolitionPlanned.22

4.WesternPacificoverGuadalupeRiveratFalconPlace.DemolitionPlanned.23

22GoogleStreetView.http://www.google.comAccessedMarch12,2015.23GoogleAerialView.http://www.google.comAccessedMarch12,2015.

5.SouthernPacific.HollisterBranch.OverPajaroRiver.SantaClara/SanBenitoCountyline.24ActiveUPRRline.NearHighway25(BolsaRoad)

24GoogleStreetView.Http://www.google.comAccessedMarch12,2015.