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DRAFTCAPSSTASKFOURREPORT
HereToday—HereTomorrow:
TheRoadtoEarthquakeResilienceinSanFrancisco
ACommunityActionPlanforSeismicSafety
Draftdate:December3,2010
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Report Summary
EarthquakesareinSanFrancisco’sfuture.Theconsequencesofthosefutureearthquakescouldbeverydifferent—worseorbetter—dependingonthepolicychoicesandactionsCityagenciesandbuilding
ownerstakenow.
TheCommunityActionPlanforSeismicSafety(CAPSS)projectstudiedfourprobableearthquakesthatcouldstriketheCityandfoundthatfutureearthquakeswoulddamagemanythousandsofbuildingsto
thepointwheretheycannotbeoccupied.TheywoulddevastatetheCity’shousingstock,andcouldhavelong‐termimplicationsontheCity’saffordabilitytomiddleandlow‐incomeresidentswhowouldbedisplacedforyears.Hundredsofpeoplecouldbekilledandthousandscouldbeinjured.TheCity
wouldloseirreplaceablehistoricbuildingsandrent‐controlledapartments.Thepricetagoftheearthquakedamagewouldbemanybilliondollars.Propertyowners,themajorityofwhomdonotcarryearthquakeinsurance,wouldbearthebruntoftheseeconomiclosses.Manymoredetailsappearina
companionreport,Potential Earthquake Impacts(ATC52‐1,2010).
Muchofthedamagefromfutureearthquakesispreventable.ThisreportsuggestsmeasuresbuildingownersandtheCitycantaketoreducerisktoprivatelyownedbuildings.Itdoesnotconsidertheriskto
publiclyownedbuildingsorinfrastructure,thoughtheserisksareconsiderable.ReducingthenegativeconsequencesoffutureearthquakesbenefitsallSanFranciscans:buildingowners,businesses,residentialtenants,andtheCitygovernment.Theserecommendationsweredevelopedwithadvice
fromanAdvisoryCommitteeofcitizensrepresentingallofthesegroups.Takingactionbeforeanearthquakestrikesislesscostlythanrepairingdamageafteranearthquake,bothintermsofthedollarsrequiredandthesocialimpactsassociatedwithhousinglosses,businessclosures,anddamaged
property.
ThetoppriorityactionsthatSanFrancisco’sCitygovernmentleadersshouldtakenowtoreducetheconsequencesoffutureearthquakesare:
• Informthepublicofrisksandwaystoreducerisk.TheCityshouldconductfocusededucationandoutreachcampaignsaimedatbuildingowners,tenants,realtorsandotherstoimprovetheir
understandingofearthquakerisksandmeasurestomanagetherisk,andtofacilitateamarketforretrofitting.Ontheirown,educationprogramsmotivateonlyalimitednumberofpeopletotakeaction.However,theyareanessentialpartofmakingotherriskreductionprogramswork.
• Adoptupdatedcodestandardsforseismicevaluationandretrofitofallcommonbuildings.AstheCitymovesforwardwithprogramstoencourageandrequiremoreretrofitsofvulnerablebuildings,itiscriticalforDBItoadoptupdatedcodestandardsapplicabletoallofthecommon
buildingtypesthatreflectboththeCity’searthquakeresilienceobjectivesandtechnicaladvancesinstructuralengineering.ItmustbecleartobuildingownerswhatbuildingseismicperformanceisacceptabletotheCity,andwhatrequirementsoffuturemandateswillbe.
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• Requireallbuildingstobeevaluatedforseismicrisk.OwnersofallbuildingsshouldevaluatetheseismicperformanceoftheirbuildingsuponsalerelativetostandardsadoptedbytheCity.If
nosaleoccurs,theyshouldevaluatetheirbuildingsbyadeadlineestablishedbasedonthebuildinguseandstructuraltype.Theresultwouldbesharedwithtenantsandprospectivebuyersandtenants,andbemadeapartofpublicCityrecords.Thisinformationallows
prospectivebuyersandtenantstoconsiderseismicissueswhenmakingdecisionsaboutpurchasingorrentingspace.Itprovidesinformationneededtoincorporateseismicissuesinmarketpricingofrealestate.Itwouldalsoprovideownerswiththeinformationneededto
decidewhethertoseismicallyretrofitvulnerablebuildings.
• Requireretrofitsofvulnerablebuildings.Ownersofvulnerablebuildingsshouldberequiredtoseismicallyretrofittheirbuildingsforstructural,fire,usabilityandfallinghazardsbyspecific
deadlines,varyingbybuildingcategory.Itislikelythatmostownerswillnotretrofittheirbuildingsunlesstheyarerequiredtodoso.Ultimately,theCitywillneedtorequireownersofvulnerablebuildingstoretrofittoimproveSanFrancisco’searthquakeresilience.Deadlinesfor
mandatoryretrofitsshowthattheCitybelievesthisissueisserious,allowsthemarkettoconsiderseismicsafetyinitspricing,andprovidescertaintyforownersofvulnerablebuildingstoplanforthefuture.
• Adoptimprovedpost‐earthquakerepairstandards.TheCityshouldenactupdatedpost‐earthquakerepairandretrofitstandardsdevelopedbyCAPSSandexpandthisapproachtootherbuildingtypes.Inacompanionreport(ATC52‐4,Postearthquake Repair and Retrofit
Requirements),CAPSSclarifiedtechnicalrecommendationstoimprovethispolicyandtoimprovethewaythisprocessbuildstheCity’sresilienceovertime.
• Clarifyresponsibilityforpreparingforandreducingriskfromearthquakes.TheCityshouldidentifyasingleofficial,the“EarthquakeCzar”,toberesponsibleforachievingearthquakeresiliencethroughmitigation,responseandrecovery.Implementingearthquakemitigation
measuresneedstobecomeanongoingconcernoftheCitywithstandingequaltootherprograms.
• Offerincentivesforretrofitofbuildings.TheCityshouldenactarangeofmeaningfulprograms
tohelpbuildingownersaffordretrofits.Ownersultimatelyareresponsiblefortheearthquakeperformanceoftheirbuildings:theyhavethemosttogainfromimprovedperformance,andthemosttolosebecauseofdamageandliability.However,theCityhasastronginterestinreducing
theamountofdamagethatoccurstoprivately‐ownedbuildingsinfutureearthquakes.Therefore,itmakessensefortheCitytoinvestinencouragingbuildingownerstomaketheirbuildingssafer.
ThisplanisacalltoactiontoinvestintheCity’sfuture.SanFranciscowillalwayshaveearthquakesinitsfuture,butwiththeproperforesightandeffort,theconsequencesofthoseearthquakescanbereducedsothattheCitycanreboundquicklyandmaintainitsuniquecharacter.
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Table of Contents
ReportSummary.......................................................................................................................................... 2
1. Introduction......................................................................................................................................... 5
2. SanFrancisco’sEarthquakeRisk .......................................................................................................... 7
LossofLife ....................................................................................................................................... 7
LossofHousingandDisplacedResidents ........................................................................................ 8
EconomicandBusinessImpacts .................................................................................................... 10
ImpactsonBuildingOwners .......................................................................................................... 11
ImpactsonVulnerableCityResidents ........................................................................................... 12
LossofCommunityCharacteror“SenseofPlace” ........................................................................ 12
LossofCityGovernmentRevenue................................................................................................. 13
Conclusion ..................................................................................................................................... 13
3. Objectives .......................................................................................................................................... 14
4. RecommendedActions:TheComprehensiveProgram ..................................................................... 20
AThree‐StepStrategytoBetterBuildings ..................................................................................... 21
RecommendedActions.................................................................................................................. 24
BuildingCategoriesandDeadlines ................................................................................................ 54
5. GettingStarted:APlanofActionfor2011through2015 ................................................................. 62
References ................................................................................................................................................. 73
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1. Introduction SanFranciscofacesadauntingearthquakethreatgivenitsproximitytoactivefaults,buildingsthatareolderthanthoseinotherWesterncities,steephillsides,areaswithpoorsoilspronetoliquefactionand
amplificationofshaking,anddense,woodenbuildingswithaproclivitytoburn.However,therearemanythingsthatcanbedonetominimizetheconsequencesoffutureearthquakesandmakeSanFranciscomoreearthquakeresilient.Actionstakentoimprovebuildingsbeforeearthquakesstrikewill
reducedamageandcasualties,speedrecovery,lesseneconomiclossesfrombusinessinterruption,reducehousingandjobslosses,andprotectcommunityvaluesandtheuniquecharacteroftheCity.SanFranciscansneedtounderstandtheriskfromearthquakesandstepstheycantaketoimprovethe
situation.
Thisreportidentifiesmeasuresthatcouldbetakenbeforeearthquakesstriketoreducedamagetoprivately‐ownedbuildings.Itrecommendsacomprehensive,long‐termmitigationprogramtoleadthe
Citytowardearthquakeresilienceandidentifiesstepsneededtocarryouttheprogram.TheprogrambeginswithbuildingpublicawarenessamongspecificgroupsofSanFranciscansandbuildsovertimetostrongermeasurestomaketheCity’sbuildingstockmorerobust.
Earthquakeriskcreatesadilemmaforbuildingowners.Mostownersunderstandthatintenseearthquakeswoulddamagetheirbuildingsandthatthecosttorepairtheirbuildingsandincomelostwhilethebuildingisrepairedorreplacedcanamounttosignificantlosses.Theyalsosensethatthey
bearadutytootherswhocouldbeharmedbydamagetotheirbuildingsandtheensuingdisruption,buttheyarefacedwithuncertainty.Thelackofcommunitystandardsabouttheappropriateactionstotakeleadstomisleadingandinconsistentopinionsaboutwhatneedstobedone.Actingnowappearsto
leavethemopentorequirementsadoptedlater.Iftheyretrofittheirbuildingnow,willitcomplywithcoderequirementsputinplaceinafewyears?Willtheyneedtore‐dothework?Someowners,especiallyhomeowners,havetriedtoimprovetheirbuildingswithoutadvicefromqualifieddesign
professionals,butthelackofstandardsleadsthemtooverspendorcarryoutprojectsthatmightbeineffective.Thisreportcallsformeasurestoprovideownerswiththeinformationandstandardsthat
wouldhelpthemdecideontherightcourseofaction.Itrecommendsgivingownersofsometypesofvulnerablebuildingsabout20yearstovoluntarilytoprotecttheirowninterestsbeforeadoptingrequirements.
However,thecourseofactioncannotbeonlyvoluntarybecausetoomuchisatstake.Therefore,thisreportrecommends,ultimately,settingmandatorydeadlinesformeetingbuildingstoberetrofit.Thereportreiteratesanearlierrecommendationforamandatoryretrofitprogramaddressingwoodframe
buildingswithfiveormoreresidentialunitsandthreeormorestories.AtaskforcecreatedbytheMayorcurrentlyisconsideringthisrecommendation.ImprovingSanFrancisco’searthquakeresiliencewilltakepersistenteffortandgovernmentinterventionoverseveraldecades.However,asthe
recommendedmeasuresareimplemented,theSanFranciscocommunitywouldweatherearthquakeswithfewercasualtiesandlessdamage,beabletomorerapidlyrecovereconomically,andpreservefor
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futuregenerationstheexciting,dynamic,culturallydiverse,historicandlivablecityresidentsenjoytoday.Inaword,SanFranciscowouldbecomemoreresilient.
Therecommendedmitigationprogramispresentedinthefollowingchapters:
• Chapter2summarizesthelikelyimpactsoffutureearthquakesinSanFranciscoasitexiststoday.Theseimpactsaredescribedindetailinthecompanionreport,Potential Earthquake
Impacts(ATC52‐1,2010).
• Chapter3recommendsobjectivestoguidetheCity’smitigationactivities.
• Chapter4recommendsactionsbuildingownersandtheCityshouldtake,andexplainswhy
theseactionsmakesensefortheCity.
• Chapter5presentsaplanofactionforthenextfewyears,2011to2015,tolaunchthe
recommendationsinthisreport.
ThisplanisacalltoactiontoinvestintheCity’sfuture.SanFranciscowillalwayshaveearthquakesinitsfuture,butwiththeproperforesightandeffort,thoseearthquakesdonotneedtobeunmitigateddisasters.
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2. San Francisco’s Earthquake Risk
FuturelargeearthquakeswillhavesevereconsequencestoSanFranciscoiftheCitydoesnotacttoimprovetheseismicperformanceofitsolderbuildings.Theseconsequencesarediscussedexhaustivelyinacompanionreport,Potential Earthquake Impacts(ATC52‐1,2010),andtheyincludedeathsand
injuries;damagedanddestroyedbuildings;lossofhousing,particularlyaffordableandrent‐controlledunits;economiclosses;joblosses;businessesclosures;reductionsinCityrevenuesatatimeofincreasingneed;lossofhistoricresources;andincreaseddifficultiesforlowandmiddleincome
residents.
KnowingtherisktheCityfacestodayisimportantbecauseitdefinesthestartingpointforreducingthoserisks.TheSanFranciscocommunitycancomparewhereitsriskistodaywithwhereitwouldlikeit
tobe,andidentifytherisksthatareleastacceptable.SanFranciscocanlearnfromNewOrleans,wheretheriskofhurricanefloodingwaswellknown,buttheimportanceofactingonthatknowledgebecamewidelyacceptedonlyafterKatrinastruck.
ThischapterbrieflyreviewsselectedimpactsoffourpossibleearthquakesthatcouldstriketheCity,highlightingimpactsthatpointtowardsmitigationprioritiesandstepstheCitycouldtaketobecomemoreresilient.Theearthquakesstudiedaremagnitude6.5,7.2and7.9earthquakesontheSanAndreas
faultattheCity’swesterncoast,andamagnitude6.9earthquakeontheHaywardfaultacrosstheBay.TheCAPSSprojectanalyzedthedamagetheseearthquakesandfiresignitedbytheshakingcouldcause,andtheimpactsofthatdamageonvariousaspectsofSanFrancisco.Selectedfindingsarediscussed
below1.Thesefindingsareestimates,notpredictions,andanynumberofcircumstancescouldcauseimpactsafterfutureearthquakestobemuchlowerorhigher.
Loss of Life
Buildingsdamagedbyearthquakescankillpeople.Somelossoflifemaybeunavoidableinlarge
earthquakes,butmeasurescanreducethedanger.Infact,SanFranciscoalreadyhastakenmanystepstoreducecasualtiesinearthquakesbyenforcingbuildingdesignandconstructionstandardsand
requiringseismicretrofitsofunreinforcedmasonrybuildingsandbracingofparapets.SanFranciscocanexpectfewercasualtiesafteralargeearthquakethanseeninlessdevelopedcountries,butdeathsarestillexpectedandsignificantriskremains.
Thestudyoffourscenarioearthquakesfoundthefollowing2:
• Dependingonthemagnitude,locationandtimeofdayofanearthquake,deathscouldrangefrom70tonearly1,000,andinjuriesrequiringmedicalcarecouldnumberfrom1,900tomore
than14,000.
1DetailedlossestimatesareavailableinthereportPotential Earthquake Risk (ATC52‐1,2010).AdiscussionofthetechnicalmethodsbehindtheestimatesappearsinPotential Earthquake Impacts: Technical Documentation(ATC52‐1A,2010).2Theseestimatesonlyincludecasualtiescausedbybuildingdamage.Theydonotincludecasualtiescausedbyinfrastructuredamage(e.g.,collapseofoverpasses)orcasualtiesduetofiressparkedbytheearthquake.
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• Casualtiescouldbemuchhigherthantheseestimatesifevenonelarge,denselyoccupiedofficeorapartmentbuildingcollapses.Therearesomelarge,multi‐storyconcretebuildingsintheCity
builtbefore1980thathavethepotentialtocollapsecatastrophicallyandkillmanypeople.
Specifictypesofbuildingsaremostlikelytocausecasualtiesinfutureearthquakes.AsshowninFigure2‐1,stiffandbrittleconcretebuildingsbuiltbeforethe1980’shavethehighestpotentialtocause
casualties.Fallingitems,suchasheavyshelves,plasterceilings,orexteriorveneer,eveninbuildingsthatarestructurallyrobust,alsocancausecasualties.Forexample,studiesfollowingthe1999KocaeliearthquakenearIstanbulfoundthatnearlyhalfofthecasualtieswerecausedbyfallinghazards3.
Casualtiescausedbysuchdamageareincludedintheseestimatesbutarenotreportedseparately.
Figure2‐1.EstimatedpercentofdeathscausedbyvariousstructuretypesinaMagnitude7.2SanAndreasscenario,averagedoverdifferenttimesofday.
Implications for risk mitigation activities:
• Structuralimprovementstoconcretebuildingsbuiltbefore1980andresidentialwoodframesoft‐storybuildingswoulddothemosttoreduceexpectedcasualtiesinfutureearthquakes.
• Casualtiescouldbefurtherreducedbymakingsurefallinghazardsareproperlysecuredsothat
theydonotfallonoccupantsduringshaking.Thisisarelativelysimple,low‐costeffort.
Loss of Housing and Displaced Residents
Housing,whichisacriticalpartofSanFrancisco’srecoveryfromfutureearthquakes,willbehardhit.Damagewillthreatentheavailabilityandaffordabilityofhousinganddisplaceresidentsforyears.The
3Petal,2004.
Concretepre‐1980;50%Residenhal
woodframesoistory;31%
Allotherbuildingtypes;
19%
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lossstudyfoundthefollowingdamagetohousingafteramagnitude7.2scenarioearthquakeontheSanAndreas:
• 85,000oftheCity’s330,000housingunitscouldnotbeoccupiedduetodamagecausedbyshaking.ThisismorethanaquarteroftheCity’shousingunits.
• 11,000ofthosedamagedhousingunitswouldneedtobedemolished.Itislikelythatmanyof
thelostunitswouldberent‐controlledapartments,which,duetostatelaw,couldnotbereplacedbyapartmentscoveredbyrentcontrol.
• Firesthatfollowtheearthquakecoulddestroymorethan5,800additionalhousingunits.
Rebuildingisaslowprocess.AftertheLomaPrietaandNorthridgeearthquakes,bothofwhichweremuchsmallerinsizethantheearthquakesstudiedbythisproject,ittookanaverageoftwotothreeyearsbeforemostheavilydamagedresidenceswererepairedorreplaced.SanFranciscocanexpectit
willtakemuchlongerforitsdamagedanddestroyedhousingunitstobeusableafterlargerearthquakes.
Housinglossduetoshakingdamageislinkedtoparticulartypesofstructures.Figure2‐2showsthe
typesofstructuresresponsibleforunusablehousingunitsafteraMagnitude7.2SanAndreasscenarioearthquake.
Figure2‐2.Theestimatedshareofhousingunitsthatcannotbeoccupiedfoundinvariousstructural
types,foraMagnitude7.2SanAndreasscenarioearthquake.
Implications for risk mitigation activities:
1&2familywoodframesoJ‐storyresidences;22%
3&4unitwoodframesoJ‐storyresidences;34%
5&moreunitwoodframeresidenceswith3ormorestories;33%
Concretebuildingsbuiltbefore1980;
6%
Allothertypesofbuildings;5%
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• Woodframeresidenceswiththreeormoreunitsaccountforabouttwo‐thirdsofthehousingunitsthatwouldnotbeusableafteraMagnitude7.2SanAndreasscenarioearthquake.These
structuresarevulnerablelargelybecauseofweakor“soft‐story”conditions.Retrofittingthesetypesofstructureswouldhaveasignificantimpacttoimprovepost‐earthquakehousingavailability.Theseretrofitsarerelativelystraightforwardandarelessexpensivethanretrofitsto
othertypesofstructures.• Rebuildingafteranearthquakewilltakealongtime.TherearestepstheCityagenciesand
buildingownerscantakepriortoanearthquaketofacilitaterapidandefficientrepairand
rebuilding,butreducingtheamountofexpecteddamageisthemosteffectivewaytospeedpost‐earthquakerecovery.
Economic and Business Impacts
Thedamagefromearthquakeshakingandfiressparkedbytheearthquakewillbecostlytohouseholds
andbusinesses.Homeandbusinessownerswillfaceanimmediateneedforfundstopayforrepairsorrelocate.Businesseswillfailandjobswillbelost.CAPSSfoundthefollowingexpectedimpacts:
• Damagetobuildingsduetoshakingandfirecouldcost$17to$54billion4,dependingonwhich
earthquakescenariooccurs.Theselossescanbecomparedtotheannualcitybudgetofapproximately$5billion.
• Additionaltypesoflosses(suchasdamagetobuildingcontentsandinventory,lostbusiness
income,lostwages,relocationexpenses,etc.)couldaddanother$5to$15billioninlosses,againvaryingbyscenarioearthquake.
• Ontopofthepreviouslystatedlosses,reducedspendingbetweenbusinessesandbyworkerscouldshrinktheCity’seconomybymorethantwopercentafteraMagnitude7.2scenarioearthquake,equivalenttoorgreaterthantheimpactsofarecession.
Inaddition,anumberofcommercialandindustrialbuildingswouldbedamaged.AftertheMagnitude7.2SanAndreasscenario,itisestimatedthatmorethan900commercialbuildingsand200industrialbuildings,outofatotalofabout7,000suchbuildingsintheCity,wouldnotbesafeforoccupancy.
AlloftheseimpactswillaffecttheCity’seconomy,businessesandjobs.Theeconomyreliesgreatlyontourismandknowledge‐basedbusinesses.ManyofthebusinessesandresidentsinSanFranciscotodaydonotneedtobelocatedhere.TheyareinSanFranciscobecauseofitsurbanamenitiesand
attractivenesstocreativeworkers.Ifthoseattractionschangeafteranearthquake,thesebusinessescouldrelocateandresidentscouldmove.ThesuccessoftheCity’stourismindustryisdirectlylinkedtopeoplewantingtovisitSanFrancisco.Tourismwilldropoffafteramajorearthquake,andhowquicklyit
reboundsiscloselylinkedtohowextensivethedamageisandhowquicklyandhowwelltheCityaswholerecoversandrebuilds.
SanFranciscoisprivilegedtohavemanysmallandlocalbusinesses;firmswith25orfeweremployees
makeupover90percentoftheCity’sbusinesses.Thesefacethehighestfailureriskafteranearthquake.Thesebusinessesoftenhavelimitedcapital,dependentirelyonrevenuesfromoneorfewlocations,
4Alldollarfiguresarein2009dollars.
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carrylimitedinsurance,andfacedifficultiesrepairingfacilities,replacingdamagedequipmentandinventory,andweatheringaneconomicdownturn.Maintainingneighborhoodbusinessoperationsand
speedingrecoveryarekeytoavoidingblightedneighborhoods.Vacantstorefrontsmeanthatbothpropertyvaluesandneighborhoodlivabilitydecline.
CertainbusinessesarecriticaltohelpingtheCityrecoverquicklyanditisdesirabletohavethem
operationalassoonaspossible.SanFranciscansneedpharmacies,grocerystores,andsimilarretailestablishmentsthatprovidetheitemsrequiredfordailyliving.Manyoftheseimportantbusinessesmaybelocatedinweakbuildingsthatwouldnotbeusableafteralargeearthquake.
Implications of business and economic losses for risk mitigation activities:
• Thecostofbuildingdamageandtheeconomicrippleeffectsofthisdamagearedaunting,andwillincreasewithtimeasSanFranciscanscompleterepairs.Retrofittingbuildingsandreducing
post‐earthquakefireriskbeforeanearthquakewouldreducethesecostsandkeeptheCity’seconomyonstrongerfooting.
• Smallandlocalbusinessesareparticularlyvulnerabletopost‐earthquakeimpacts.These
businessesmightbetenantsinbuildingswithalimitedabilitytoaddressseismicsafetyconcernsandrelyonnearbyresidentsascustomers.TherearestepstheCitycantaketominimizeearthquakeimpactstosmallandlocalbusinesses.
• Thereareparticularretailers,suchaslargegrocerystoresandpharmaciesthatarecriticaltotheCity’sresidentsfollowingearthquakes.TheCityhasaparticularinterestinmakingsuretheseretailerscanservethecommunityquicklyafteradisaster.
Impacts on Building Owners
Buildingownersstandtolosethemost.Almosteverybuildingwouldbedamagedbyanintenseearthquaketodegreesthatvarybybuildingweaknesses,groundconditions,proximitytothefaultand
whethertherearefires.Buildingownersbearthecostsofrepairs,aswellascoststorelocatewhiledamageisrepaired.Commercialownersloseincomefromrents.Existinglenderscontinuetoexpectpayments.Owners’abilitytorepairtheirbuildingsdependsontheirabilitytocontinuemakingpayments
onexistingdebtandtofundrepairsfromsavings,liquidatingotherassets,orborrowingadditionalsums.Thosewithoutsufficientassetsandwithlimitedincomemightnotqualifyforadditionalloans.Incontracts,retrofittingbeforeearthquakesstrikeallowsownerstheopportunitytoplanandfinance
measurestoprotecttheirassetsandimprovethechancesthattheywillbeabletoaffordrepairsandrecoverquicklyafterfutureearthquakes.
Privatebuildingownerscannotrelyonoutsidesourcesoffundstohelpthemrecover.FEMA’sIndividual
andFamilyGrantprogramwouldcoversomeofthecostofminorrepairsandtemporaryhousing,butdoesnotdealsufficientlywiththemagnitudeofcoststhatwillfaceSanFranciscans.FewerthantenpercentofSanFranciscanhomeownerscarryearthquakeinsurance.Thecostofinsurancepremiumsis
highrelativetothecoverageoffered.Manyarguethatitisbettertoinvestinretrofittingtoreducelossesthantospendsimilarsumsovertimeforinsurance.
Implications for mitigation activities
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• Ownersshouldknowtheriskstheyfaceandmeasurestheycantaketomanagetheriskssotheycanmakeinformeddecisions;
• Buildingowners’investmentsshouldnotbejeopardizedbyotherownerswho,byfailingtoaddressearthquakeandfirerisks,allowdamagethataffectsentireneighborhoods.
Impacts on Vulnerable City Residents
Someprivately‐ownedbuildingsthatservetheCity’smostvulnerablepopulationsmaynotbesafe
duringorusableafterfutureearthquakes.Thefollowingtypesofimportantservicesareoftenlocatedinprivately‐ownedbuildings:
• Privateschools—Kthrough12andcolleges
• Preschoolsandchildcarecenters• Assistedlivingfacilitiesfortheelderlyordisabled• Medicalofficesandclinics,dialysiscenters,medicalsuppliers,etc.
• Nonprofitsthatservevulnerablepopulations(e.g.,mealdeliveryandpublickitchens)• Singleroomoccupancyhotelsinolderbuildings
Thebuildingsthathousetheseservicesarenobetterthanthegeneralbuildingstockandwouldsuffer
similardegreesofdamage,ifnotmore,inearthquakes.Manyoftheseorganizationsrentspaceinolderbuildingswhererentsarelowerandnearthepopulationtheyserve.Someofthesebuildingsmightbeunsafe.Extensivedamagewillinterruptcriticalsupportforthosedependentontheservicesthese
organizationsprovide.Communityserviceorganizationshavelittleleveragetocauseownerstoretrofitweakbuildings.
Implications for risk mitigation activities:
• OrganizationsservingtheCity’smostvulnerableresidentsmaybelocatedinbuildingsthatwillnotbesafeduringorusableafterfutureearthquakes.ThisCity’selderly,disabled,childrenand
poorwillneedtheservicestheseorganizationsprovideintheaftermathofanearthquake.ItmakessensefortheCitytohelpfinanciallychallengedorganizationstobecomemoreresilient.
Loss of Community Character or “Sense of Place”
SanFrancisco’scharactercouldbedefinedinmanyways,butsurelyitispartlycapturedbythe
distinctiveflavoroftheneighborhoodsandthediversityoftheCity’sresidents.Amajorearthquakewouldaffectboth.
Earthquakedamageanddamagefromfiressparkedbyearthquakeshakingcoulddestroymanybuildings
thatdefineSanFrancisco’slookandfeel,includinghistoricbuildings.Demolishedbuildingswouldbereplacedwithbuildingshavingmodernconstructionmaterialsthatwouldlookandfunctiondifferently.Manyofthemwouldbelarger,takingadvantageofcurrentheightanddensitylimits.
EarthquakedamagetohousingwouldhavebigimpactsontheCity’slowestincomeresidents,seniorcitizens,peoplewithfixedincomesandthosewithdisabilities.Duetoavarietyoffactors—including,butnotlimitedto,fewvacancies,expensiverepairs,andlossofrent‐controlledunits—rentsforapartments
arelikelytoincreaseafteranearthquake.CombinedwithshortandmediumtermimpactsontheCity’s
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businessesandjobmarket,thiscoulddrivedemographicchangesthatreduceSanFrancisco’ssocioeconomicdiversity.
Implications for risk mitigation activities:
• Architecturallyattractiveprivatebuildings,includinghistoricbuildingsanddistricts,areatriskfromearthquakeandfire,andprogramstolimitbuildingdamageandearthquaketriggeredfires
wouldprotecttheseirreplaceableresources.• Riskreductionmeasurestargetedathousingforlow,middleandfixedincomehouseholds
wouldhelpkeepSanFrancisco’spopulationdiverse.
Loss of City Government Revenue
DamagetoprivatelyownedbuildingsaffectstheCitygovernment’sbottomline.AnearthquakewouldreducerevenueatatimewhenexpensesareincreasingbecauseCity‐ownedfacilitiesneedrepairandresidentsneedassistancetorecoverfromtheearthquake.TheCitycanexpectshortandmediumterm
declinesinpropertytax,businesstax,hotelroomtax,salestax,andotherincomesources.FederalfundswillonlycoverafractionoftheCitygovernment’srebuildingandrecoveryexpenses.
Implications for risk mitigation activities:
• Limitingdamagetoprivatelyownedbuildingsandtheensuingfinancialimpactswouldimprovepost‐earthquakegovernmentrevenuesfromproperty,salesandhoteltaxes.
Conclusion
TheanalysisoffourpossibleearthquakestostriketheCitymakesitclearthat,asitistoday,theCityshouldexpectalotofdamagefromfutureearthquakes.Asdescribedabove,widerangingconsequenceswillflowfromthatdamage,causingrecoverychallengesforallresidents,especiallybuildingowners.San
Franciscowillrecover,butitwillbeforeverchangedbyloosingworkersandbusinessesthatrelocateratherthanforrecovery.Takingstepstomitigateearthquakedamagebeforethenextearthquakestrikescanavoidmanyoftheseconsequences.Inthefollowingchapters,thisreportrecommendsa
comprehensiveprogramfortheCitytoimproveitsearthquakeresiliency.
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3. Objectives
EarthquakesareinSanFrancisco’sfuture.Theconsequencesofthosefutureearthquakescouldbeverydifferent—worseorbetter—dependingonthepolicychoicesandactionsCitydepartmentsandbuildingownerstakenow.ItisuptoSanFranciscanstojoininaninformedandopenprocesstodecidewhat
levelandtypesofconsequencestheyarewillingtoaccept.SanFranciscansshouldconsiderthreefundamentalquestions:Howmanycasualtiesareacceptable?Howmuchdamageanddisruptionareacceptablefromshakingandfiressparkedbythatshaking?HowquicklyshouldtheCityreturntoa“new
normal”followingearthquakes?Thecitizenscommitteethatadvisedthepreparationofthisstudyconcludedthattheexpectedcasualtiesaretoomany,thedamageanddestructiontoogreat,andthetimetorecovertoolong.ManyoftheattributesSanFranciscansvalueareatrisk.SanFrancisco,its
neighborhoodsandpeople,wouldbechangedinregrettablewaysbyalargeearthquake.Thisneednotbethecase.
Objectivesareneededtoguidetheeffortstoimproveearthquakesafetyandpost‐disasterresiliencyin
SanFrancisco.Thischapterrecommendsmitigationobjectives,andthefollowingchaptersproviderecommendationsandalong‐termplantomeettheobjectives.
ObjectivesareimportantbecausetheyshapethepoliciestheCityneedstopursue.Theobjectives
indicateprioritiesforwhichcategoriesofbuildingsshouldbeevaluatedfirst,andhowquicklyweakbuildingsshouldbestrengthened.Theyguidedevelopmentofthestandardsusedforidentifyingunacceptablyweakbuildingsandthemeasuresneededtostrengthenthemtoachievethedesired
performance.Theobjectivesjustifyincentivesthathelpbuildingownerstakeactionsthatbenefitthewidercommunity.
Thisreportproposesthefollowingobjectivestoguidemitigationactionsandpriorities:
Afterexpectedearthquakes5
a) Residentswillbeabletostayintheirownhomesb) Residentswillquicklyhaveaccesstoimportantprivately‐runcommunityservices
c) Nobuildingwillcollapsecatastrophicallyd) Businessesandtheeconomywillquicklyreturntofunctionality
e) TheCity’ssense of placewillbepreserved
TheseobjectivesarenotnewtotheCity.TheyrespondtoexistingpoliciesprovidedintheSanFranciscoGeneralPlan.Forovertwodecades,theCityhasclearlystatedthatearthquakesafety,housing,
5ThedamagetheCityexperiencesinfutureearthquakesdependsalotontheintensityofearthquakeshaking.Shakingintensitydependsonanumberoffactorsincludingthelocationofthefaultwhereanearthquakeoccurs,magnitudeoftheearthquake,themannerthatthefaultrupturepropagates,andthecharacterofthegroundunderlyingtheCity.Therecommendationsinthisreportarebasedontheintensityofshakingusedbythebuildingcodeforthedesignofnewbuildings.InitsResilientCityreport(SPUR,2009),SanFranciscoPlanningandUrbanResearch(SPUR)calledthisthe“expectedearthquake”becauseshakingofthisintensityislikelytooccurduringthelifetimeoftheCity’sexistingbuildings.
WorkingDraftCAPSSTask4Report page15
neighborhoodcharacterandneighborhood‐servingbusinessesarepriorities.(SeesidebarforadiscussionofhowtheobjectiveslinktoexistingCitypolicy.)
MeetingtheseobjectiveswillrequiremanySanFranciscanstoimprovetheirbuildingssothattheyexperiencelessdamagefromearthquakeshakingandresultingfires.ItwillrequireCitygovernmenttodevelopnewprogramsandrethinkexistingones.Therearemanywaystostructureobjectives.This
reportproposesgeneralobjectivesintermsofvisualizinghopesforhowtheCitywilllookafterfuturelargeearthquakes.Theseobjectivesarelong‐termandideal,andwhenreachedwouldresultinamoreearthquake‐resilientSanFrancisco.
Lookingateachoftheproposedobjectivesinmoredetailprovidesinsightsintowhyeachisimportant:
a) Residents will be able to stay in their own homes
KeepingSanFranciscansinSanFranciscoafteranearthquakeiscriticaltotheCity’srecovery.
ResidentswillhelprevivetheirneighborhoodsandtheCity’seconomy.Itmakessenseforownerstoinvestin,andtheCitygovernmenttoencourage,makingtheexistinghousingstockrobust,ratherthancopingwithamajorhomelessnesscrisis,providinglong‐termtemporary
housing,andrebuildingalargepartoftheCity’shousingafteranearthquake.Retrofittingresidentialbuildingsknowntobevulnerablewouldsavelivesandmoney,andspeedrecovery.
b) Residents will quickly have access to important privately‐run community services
SanFranciscansdependonnumerousprivateentitiesforessentialaspectsoftheirdailylives.Theseentitiesrangefromnon‐profitsthatprovidehousing,foodandcaretodisabled,elderlyorlow‐incomeresidents,tomedicalclinicsandsuppliers,togrocerystoresandpharmacies,today
carecenters,schoolsandassistedlivingfacilities.Residentsneedtheseservicestobeoperationalshortlyafteranearthquake.Manyofthebuildingsthathousetheseservicesneedto
bestrengthenedsotheycanwithstandfutureearthquakes.
c) No building will collapse catastrophically
Today,manybuildingsintheCityusedasresidencesandofficeseverydayhavethepotentialfor
dramaticandlethalcollapses.Thesebuildingscanandmustbemadesafer.
d) Businesses and the economy will quickly return to functionality
TheCity’srecoverydependsonafunctionaleconomy.Particularbusinessesareespecially
vulnerabletoearthquakeimpacts,suchassmall,localbusinesses,knowledge‐basedbusinessesandvisitorservingbusinesses.Ifrecoveryisslow,manybusinesseswouldfailandotherscouldeasilyrelocatetoothercommunities.Retrofitofvulnerablebuildingswouldhelpassure
businessesstayafloatandinSanFranciscoafteranearthquake.
e) The City’s sense of place will be preserved
KeepingSanFranciscodiverseandmaintainingitsarchitecturalcharacterisimportantto
preservingtheCity’ssoul.RetrofittingvulnerablebuildingswouldpreventfutureearthquakedamagefrommakingtheCityunaffordabletolowandmiddleincomeresidentsandmaintain
WorkingDraftCAPSSTask4Report page16
theculturalandarchitecturalcharacteroftheneighborhoods.ManyoftheCity’solderhistoricbuildingsandculturalresourcesneedtobepreservedandprotected.
Theobjectivesandrecommendationsinthisreportarefocusedinanumberofways:
• ThisreportwasdevelopedthroughaprojectoftheDepartmentofBuildingInspection(DBI),therefore,itsobjectivesandrecommendationsprimarilyfocusonissuesthatarecentraltoDBI’s
mission.Earthquakes,however,donotrespectdepartmentalboundaries.Therefore,thisreportalsoincludesrecommendationsrelevanttootherCityagencies,butmanyoftheseideasarenotarticulatedasspecificallyasthosecentraltoDBI.
• Thisreportfocusesonmitigation:stepstakenbeforeearthquakesstriketoreducetheirimpacts.Itdoesnotfocusonemergencyresponseorpreparednessplanning,nordoesitfocusonpost‐earthquakerecoveryplanning,whichareallessentialingredientsforachievingresilience.
However,thelinesamongalltheseactivitiesareindistinct;recommendationsinthisreportmaycontributetootheraspectsofearthquakeplanning.
• Thisreportfocusesonreducingdamagetoprivatelyownedbuildingsandtheconsequencesthat
flowfromthatdamage.Itdoesnotcovergovernmentbuildingsorinfrastructure(roads,bridges,water,sewer,gas,electricity,etc.),althoughtheearthquakeresilienceofbothisofmajorimportancetotheCity.
TheobjectivesrecommendedinthisreportcannotbeachievedbytheDepartmentofBuildingInspectionactingalone.Norisrequiringownerstostrengthenweakbuildingssufficienttoachievethem.AchievingtherecommendedobjectivesrequiresactionsbyotherCityagenciesandprivatepartners
joininginalong‐term,comprehensiveeffort.TheobjectivesbuildonandshouldbeintegratedwithinthepolicyfabricoftheCityasexpressedinordinances,theGeneralPlananditsCommunitySafety
Element,andthroughthepoliciescarriedoutbythePlanningCommission,HistoricBuildingCommission,FireDepartment,RentStabilizationandArbitrationBoard,andotherbodiesresponsibleforthestewardshipandmanagementoftheresourcesatrisk.
Theobjectivesproposedinthisreportareambitious.Reachingthemwilltakeyearsofsustainedeffort.ItwillrequireusingmanyapproachestotackletheCity’srisk.ItwouldbeaninvestmentintheCity’sfuture,arecognitionthattheCitydoesnotwanttopassalloftheresponsibilityforearthquakesonto
futuregenerations.Inthefollowingchapters,thisreportrecommendsalong‐termandcomprehensiveprogramofactivities.
SIDEBAR1:ExistingCityPolicy
TheobjectivesandactionsproposedinthisreportareintendedtocarryoutexistingpoliciesoftheCity
andCountyofSanFrancisco.TheCityarticulatesobjectivesintheGeneralPlan,shapedby1986’sPropositionMthatestablishedeightPriorityPoliciesfortheprotection,preservationandenhancementoftheeconomic,socialculturalandestheticvaluesthatestablishthedesirablequalityandunique
characterofthecity.TheobjectivesandprioritiesproposedinthisreportrespondtofiveofthesePriorityPolicies:
• Thatexistingneighborhood‐servingretailusesbepreservedandenhancedandfuture
opportunitiesforresidentemploymentinandownershipofsuchbusinessesenhanced;
WorkingDraftCAPSSTask4Report page17
• Thatexistinghousingandneighborhoodcharacterbeconservedandprotectedinordertopreservetheculturalandeconomicdiversityofourneighborhoods;
• ThattheCity'ssupplyofaffordablehousingbepreservedandenhanced;• ThattheCityachievesthegreatestpossiblepreparednesstoprotectagainstinjuryandtheloss
oflifeinanearthquake.
• Thatlandmarksandhistoricbuildingsbepreserved.
TheCommunitySafetyElement,anintegralpartoftheGeneralPlan,providesadditionalCitypolicies.TheCityiscurrentlyupdatingtheexistingCommunitySafetyElement.The2007draftCommunitySafety
ElementrecognizesthatexistinghazardousstructureshavethegreatestpotentialforlossoflifeandotherseriousimpactsresultingfromanearthquakeandthattheCityshouldcontinuetoexplorewaystoreducethisrisk.Itcallsformoredetailedplans.
ThegoalsofthependingrevisionstotheCommunitySafetyElementmirrorthoseofthisreport.Theycallforprotectingagainstinjuryandlossoflife;reducingsocial,culturalandeconomicdislocations;andencouragingrapidrecovery.SomeofthemanyrelevantobjectivesandpoliciesintheSafetyElement
draftappearbelow:
OBJECTIVE1:REDUCESTRUCTURALANDNON‐STRUCTURALHAZARDSTOLIFESAFETYANDMINIMIZEPROPERTYDAMAGERESULTINGFROMFUTUREDISASTERS.
POLICY1.9—CompleteremainingupgradesoftheUnreinforcedMasonryBuildingSeismicHazardReductionProgramandtheparapetSafetyProgram.
POLICY1.10—Assesstheriskspresentedbyothertypesofconcretestructuresandreducetherisksto
theextentpossible.
POLICY1.11—Reducetheearthquakeandfirerisksposedbyoldersmallwood‐frameresidential
buildingsthrougheasilyaccomplishedhazardmitigationmeasures.
POLICY1.12—Exploreincentivesforprivatehomeownerstoupgradetheirbuildings.
POLICY1.14—Preserve,consistentwithlifesafetyconsiderations,thearchitecturalcharacterof
buildingsandstructuresimportanttotheuniquevisualimageofSanFrancisco,andincreasethelikelihoodthatarchitecturallyandhistoricallyvaluablestructureswillsurvivefutureearthquakes.
OBJECTIVE2:BEPREPAREDFORTHEONSETOFDISASTERBYPROVIDINGPUBLICEDUCATIONAND
TRAININGABOUTEARTHQUAKESANDOTHERNATURALANDMAN‐MADEDISASTERS,BYREADYINGTHECITY’SINFRASTRUCTURE,ANDBYENSURINGTHENECESSARYCOORDINATIONISINPLACEFORAREADYRESPONSE.
POLICY2.2—Encouragebusinessesandhomeownerstoevaluatetheirearthquakerisks.
OBJECTIVE4.ASSURETHESOUND,EQUITABLEANDEXPEDIENTRECONSTRUCTIONOFSANFRANCISCOFOLLOWINGAMAJORDISASTER.
POLICY4.7—DevelopandadoptaRepairandReconstructionOrdinance,tofacilitatetherepairandreconstructionofbuildings.
ENDOFSIDEBAR
WorkingDraftCAPSSTask4Report page18
SIDEBAR2:SanFranciscoPlanningandUrbanResearch(SPUR)Recommendations
TheproposedobjectivesinthisreportalsobuildonSPURrecommendations.InitsResilientCityreport6,
SPURrecommendedrecoverytargetsfortheCityafteranearthquake.SPUR’sintentisfortheCitytorequirethoseimprovementsneededtoassureaquickrecovery—orthelevelofresiliencedesiredforeachstageofrecovery.SPURdefinedthreestages,orphases,ofdisasterresponseandrecovery.
Phase1,fromonetosevendays,istheperiodofinitialemergencyresponseandstagingforreconstruction.Withinthistimeframe,SPURproposestheserecoverytargets:
• Within24hours,hotelsdesignatedtohouseemergencyresponseworkersaresafeanduseable,
sheltersareopen,andalloccupiedhouseholdsareinspectedbytheiroccupants.Fewerthanfivepercentofalldwellingunitsshouldbeunsafetooccupy.Residentscanshelterinplaceinsuperficiallydamagedbuildings,evenifutilityservicesarenotfunctioning.
• Within72hours,theinitialrecoveryandreconstructioneffortswillbefocusedonrepairingresidencesandschoolstoausablecondition.
Phase2,from30to60days,isthetimeframewhenhousingisrestoredandongoingsocialneedsare
met.Withinthistimeframe,SPURproposestheserecoverytargets:
• Within30days,ninetypercentoftheneighborhoodbusinessesareopenandservingtheworkforce.
• Reconstructioneffortswillbefocusedonrepairingresidences,schoolsandmedicalproviderofficestoausablecondition.
Phase3,coveringseveralyears,iswhenlong‐termreconstructioniscompleted.Withinthistimeframe,
SPURproposestheserecoverytargets:
• Alldisplacedhouseholdsreturnhomeorarepermanentlyrelocated.
• Ninety‐fivepercentofthecommunityretailservicesarereopened• Fifty‐percentofnon‐workforcesupportbusinessesarereopened.• Withinthreeyearsallbusinessoperationsarerestoredtopre‐earthquakelevels.
SPURalsoestimatedtheexpectedcurrentstatusforselectedusesfollowinganexpectedearthquake.ThetargetrecoverytimesandcurrentstatusapplicabletoprivatebuildingsaresummarizedinTable3‐1.
Table3‐1.TargetStatesofRecoveryforSanFrancisco’sBuildings
Phase1(Hours)
Phase2(Days)
Phase3(Months)InfrastructureClusterFacilities
4 24 72 30 60 4 36 36+
95percentofresidentsshelterinplace
B
EmergencyResponderHousing
B
PublicShelters
B
6SPUR,Urbanist,February2009
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Schools
C
Medicalprovideroffices
C
90percentneighborhoodretailservices
C
Allresidencesrepairedorrelocated
D
95percentofneighborhoodretailbusinessesopen
D
50percentofficesandworkplacesopen
D
Allbusinessesopen
D
LegendPerformanceMeasure
DescriptionofUsabilityafterexpectedevent
Symbol
CategoryB
SafeanduseableduringrepairsB
CategoryC
SafeandusableaftermoderaterepairsC
CategoryD
SafeandusableaftermajorrepairsD
Expectedcurrentstatus
ENDOFSIDEBAR
WorkingDraftCAPSSTask4Report page20
4. Recommended Actions: The Comprehensive Program
SanFranciscanshaveachoice:eitherabsorblossesfromfutureearthquakesandendurethepainfulandprotractedrecoverythatfollows,orundertakemeasurestoreducethelossesandimpactsfromthose
earthquakes.ReachingtheobjectivesproposedinthepreviouschapterwilltakeyearsofsustainedeffortbytheCity,itsdepartmentsandresidents.Thischapterrecommendsthespecificactionsneededtoreachthoseobjectives,inacomprehensiveandphasedeffort.
Informeddecision‐makingformsthebasisofthecomprehensiverecommendedprogramthatfollows.AllSanFranciscans,homeowners,businessowners,tenantsandofficials,needtounderstandhowearthquakeswillaffectthem,andknowmeasurestheycantaketoreducetheseimpacts.Everyone
shouldbeempoweredtomakeriskreductiondecisionsintheirbestinterests,butnoteveryonewill.Therefore,therecommendedapproachstepsthroughaseriesofactivities,atfirstencouragingimprovementstobuildings,andlaterrequiringsuchimprovementstobuildingsthatthreatenthelarger
communitywelfare.
Thischapterisorganizedintothreesections:
• AThree‐StepStrategytoBetterBuildings
Thissectionprovidesadiscussionoftheoverallrecommendedthree‐stepapproachtheCityshouldusetoreachitsearthquakemitigationobjectives.Itbeginswithfacilitatingamarketinwhichearthquakeperformanceisvalued.Next,buildingownerswouldberequiredtoevaluate
theseismicvulnerabilityoftheirbuildingsandmakethefindingspublic.Last,vulnerablebuildingswouldberequiredtoretrofitbysetdeadlines,whichvarybycategoryofbuilding.
• SpecificRecommendedActionsThissectionrecommendssixteenspecificactionstheCityshouldtaketocarryoutthethree‐stepstrategytoreduceearthquakerisk.Together,theseactionscombinetoformacomprehensive
approachthataddressestherecommendedobjectives.Manyoftherecommendedactionscontributetomeetingseveraloralloftheobjectives.
• BuildingCategoriesandPriorities
ThissectionrecommendsaschemetocategorizeandprioritizetheCity’sbuildingsbasedon
bothbuildingstructuretypeanduse.Itpresentsarecommendedscheduleformandatoryseismicretrofitofeachvulnerablebuildingcategory.
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A ThreeStep Strategy to Better Buildings
Therecommendationsinthisreportaimtousebothmarketforcesandothermechanismstodriveactionstoreduceearthquakerisks.Publicawarenessandunderstandingisessential.Knowledge
providestheinformationneededtogiveearthquakeperformanceafinancialvalue.Ownersandoccupantsofbuildingsareempoweredtomakeearthquakeriskmanagementdecisionsintheirbestinterestswhentheyknowabouttheearthquakeriskofthebuildingstheyliveinoruse,understandhow
theriskaffectsthem,andknowwhattheycandoaboutit.Theycanaddressearthquakevulnerabilitywhenbuying,leasing,financing,insuring,repairingorrenovatingbuildings.Currently,fewownersortenantshaveanyknowledgeabouthowthebuildingstheyownorusearelikelytoperformin
earthquakes,whichmaycontributetoinaction.Misconceptions,bothoverandunderestimatingrisk,abound.
MarketforceshavebeenworkingwelltoimproveSanFrancisco’scommercialbuildingstock.Lenders
andinsurersforcommercialbuildingsroutinelyrequireananalysisoftheexpectedearthquakeperformanceofabuildingbeforetheywilllendorinsure.Theygenerallyrequirethatexpectedbuildingdamagebelessthan20percentofthebuildingreplacementcost.TheresultisthattheCity’s
commercialbuildingstockhasundergonemanyupgradesovertheyearsandisexpectedtofaresignificantlybetterinfutureearthquakesthantheCity’shousingstock.Lendersandinsurersdonothavethesamerequirementsformostresidentialbuildingsand,foravarietyofreasons,theseindustriesare
unlikelytoenactsuchrequirementsanytimesoon.Therefore,itmakessensefortheCitytostepinandhelpbuildamarketforseismicallyrobusthousing.
Thegoalofthestrategyrecommendedbythisreportistoincreasethenumberofseismicretrofitsvoluntarilyconductedbyownersofthemostvulnerablebuildings.Asmoreretrofitsareconducted,retrofittingtechniqueswillimprove,engineeringandconstructionworkwillgrowmoreefficientandless
costly,andthecommunityasawholewillbegintobenefitfromseismicremediationbybuildingowners.However,experiencewiththeunreinforcedmasonrylawinSanFranciscoandotherCaliforniacommunitiesindicatesthatmanyownerswillnotevaluateorretrofittheirbuildingsuntilrequiredtodo
so.Deadlinesrequiringevaluationsandretrofittingofweakbuildingsareneededtogivemarketforcesapush,eventhoughitmaybeappropriatetosetsomeofthesedeadlinesfordecadesinthefuture.RequirementsanddeadlinesshowthatearthquakeriskisanissuetheCitygovernmenttakesseriously;
incontrast,apurelyvoluntaryprogramsuggeststhatthisissueisnotviewedasimportant.Deadlinesforrequiredaction,basedontheCity’sprioritiesandthecapacityofthegovernmentandprivatesectorstodothework,areneeded.
TheCityhasastronginterestinmakingsureownersmakeinformeddecisionsabouttheirbuildingsandstrengthenthosethataremostvulnerable.UnsafeanddamagepronebuildingsthreatenthesafetyofCityresidents,theviabilityofneighborhoods,thelong‐termaffordabilityoftheCity’shousing,thesocio‐
economicdiversityoftheCity,andthelargerCityeconomy.Individualbuildingfailuresweakenthefabricoftheentirecommunityandcanbeeconomicallyruinousfortheowner,tenantsandneighbors.Damagedbuildingsarepronetofireignitionsthatcouldspreadforblocksorconsumeentire
neighborhoods.Thecumulativeimpactofindividualfailuresisdevastating;conversely,thecumulativeimpactofindividualretrofitswillprotectattributesSanFranciscansvalue.
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A ThreeStep Strategy
Thisreportrecommendsathree‐stepstrategytoengagemarketforcestoencouragestructuralretrofits,enactmeasurestoreducefiredamage,andpromotenon‐structuralriskreductionmeasures.Thestrategyfollowsthefollowingsteps:
Step1. Facilitateamarketinwhichearthquakeperformanceisvalued;
Step2. Nudgethemarketbyrequiringevaluationuponsale,orbyadeadline;and
Step3. Requireretrofittingbyadeadline.
Byapplyingthisthree‐stepprograminaphasedmanner,SanFranciscowouldhelpbuildingsownersaddresstheirriskandtakeactionsthatbenefitthebroadercommunity.Notallbuildingcategoriesneed
topassthrougheachphase.Forexample,theefforttostrengthenweakunreinforcedmasonrybuildingsbeganwithstep3,inrecognitionoftheirlethalrisk.
Eachofthestepsisdescribedbelow:
• Step1:Facilitateamarketinwhichearthquakeperformanceisvalued
Initially,theCitywouldtakestepstoencouragebuildingownerstohavetheirbuildingsevaluated
andretrofitted,ifvulnerable.Thisinvolvesthefollowingtypesofactivities:
o Conductingfocusededucationandoutreachcampaignsthatpresentspecificstepsthat
particulartypesofbuildingowners,tenants,businessowners,constructionprofessionals,andotherscantaketoreduceearthquakeimpacts.Knowinghowtoreduceriskisanecessaryfirststeptoaction(seerecommendation1).
o Adoptingupdatedcodestandardsforseismicevaluationandretrofitofallcommonbuilding
typesinSanFrancisco.AstheCitymovesforwardwithprogramstoencourageandrequire
moreretrofitsofvulnerablebuildings,itiscriticalforDBItoadoptupdatedcodestandardsthatreflectboththeCity’searthquakeresilienceobjectivesandtechnicaladvancesinstructuralengineering.Itmustbecleartobuildingownerswhatbuildingseismicperformanceis
acceptabletotheCity,andwhatrequirementsoffuturemandateswillbe(seerecommendation2).
o Offeringmeaningfulincentivestobuildingownerswhoretrofitvoluntarily.Ownersultimatelyareresponsiblefortheearthquakeperformanceoftheirbuildings:theyhavethemosttogainfromimprovedperformance,andthemosttolosebecauseofdamageandliability.However,
theCityhasastronginterestinreducingtheamountofdamagethatoccurstoprivately‐ownedbuildingsinfutureearthquakes.Therefore,itmakessensefortheCitytoinvestinencouragingbuildingownerstomaketheirbuildingssafer(seerecommendation8).
o Providingtechnicalassistancetohelpresidentsandbuildingprofessionalstoevaluateand
seismicallyretrofitbuildingsefficientlyandinaccordancewithCitycodes.Technicalassistance
WorkingDraftCAPSSTask4Report page23
canrangefromdevelopingstandardplansetstoorganizingtechnicaltrainingsessions(seerecommendation11).
ManyoftheseactivitieswillrequiretheDepartmentofBuildingInspectiontoworkwithotherdepartmentsandprivatepartners.Duringallstages,existingrequirementstoevaluateandretrofitbuildingswhenexpanding,changinguseorrepairingdamagewouldremaininplace.
• Step2:Nudgemarketbyrequiringevaluationuponsaleorbydeadline
Thesecondstep(recommendation3)wouldrequireownerstocompleteanengineeringevaluationpriortosellingbuildingsthatcomparesabuildingtothecodeperformancestandardsthatDBIhasadoptedforeachtypeofbuilding.Thefindingsoftheseevaluationswouldbesharedwithtenants
andprospectivebuyersandtenants,andbemadeapartofpublicCityrecords.Theevaluationswouldidentifystructuralweaknesses,fireignitionandspreadrisks,fallinghazardsthataffectsafety,vulnerablebuildingelementsthataffectwhetherabuildingcouldbeusedafteranearthquake,and
groundfailurehazards.Thesestandardswouldspecifywhetheritislikelythattheoccupantswouldbesafeandabletoshelter‐in‐placefollowingtheexpectedearthquake.Theevaluationshouldclearlyidentifybuildingswithunsafeweaknesses,or“killerbuildings.Apotentialbuyercouldthen
decideonthebuilding’svalueand,ifitispurchased,whethertoretrofititornot.Buyersandsellerswouldnegotiatesalespricesandfinancingbasedinpartonthefindingsoftheengineeringevaluations.TheCitywouldsupplementthisphasebyrequiringcertaincategoriesofbuildings,such
asthosethatareinfrequentlysold,condominiumswithmultipleowners,andownersofmanybuildings,suchasauniversityorinstitutionalinvestor,tocompleteevaluationsaccordingtoaschedule.ThisshouldincluderequiringlargerbuildingstoparticipateintheCity’sBuilding
OccupancyResumptionProgram(BORP).BORPisaCityprogramthatallowsbuildingownerstoengageanengineerbeforeanearthquaketoinspecttheirbuildingfordamageafteranearthquake.Itcanexpeditereoccupancyafteranearthquake.
• Step3:Requireretrofitbyadeadline
Thethird,andlast,stepwouldrequireretrofittingvulnerablebuildingsbyadeadline.Thisistheapproachusedtoaddressunreinforcedmasonrybuildingsduringthe1990s.Thisstepensuresthatownersofvulnerablebuildingsthatthreatenthebroadercommunity’swelfareultimatelyimprove
thosebuildings.DeadlinesformandatoryretrofitsshowthattheCitybelievesthisissueisserious,allowsthemarkettoconsiderseismicsafetyinitspricing,andprovidescertaintyforownersofvulnerablebuildingstoplanforthefuture.Therequirementsoftheearlierphaseswouldremainin
effect.Thisstepisproposedinrecommendation4.
ThisreportrecommendsthattheCityapplythethree‐stepapproachtokeycategoriesofbuildingsintheCityinaphasedmanner,whichisdiscussedfurtherlaterinthereport.
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Recommended Actions
ThischapterpresentsspecificrecommendedpoliciestoreduceSanFrancisco’searthquakerisk.Thefifteenkeyrecommendations,presentedbelow,areneededtoreducevulnerabilityfromearthquake
shaking,fallinghazards,groundfailureandpost‐earthquakefire.Someoftherecommendedactionsdirectlytacklethesourcesofrisk;othersareneededtosustaintheCity’smitigationeffortsoverthenextfewdecades.Eachofthefifteenrecommendationsisdescribedinmoredetailinthepagesthatfollow,
includingadiscussionofwhateachrecommendationentailsandwhyitisagoodchoiceforSanFrancisco.
Recommended actions to reduce earthquake risk Additional details
1. Informthepublicofrisksandwaystoreducerisk.TheCityshouldconduct
focusededucationandoutreachcampaignsaimedatbuildingowners,tenants,realtorsandotherstoimprovetheirunderstandingofearthquakerisksandmeasurestomanagetherisk,andtofacilitateamarketforretrofitting.
pageXX
2. Adoptupdatedcodestandards.TheCityshouldadoptcodestandardsforseismicevaluationandretrofitofallcommonbuildingtypesinSanFrancisco.
pageXX
3. Requireallbuildingstobeevaluatedforseismicrisk.Ownersofallbuildings
shouldevaluatetheseismicperformanceoftheirbuildingsuponsalerelativetostandardsadoptedbyDBIor,ifnosaleoccurs,byadeadlineestablishedbasedonthebuildinguseandstructuraltype.Theresultswouldbeshared
withtenantsandprospectivebuyersandtenants,andbemadeapartofpublicCityrecords.
pageXX
4. Requireretrofitsofvulnerablebuildings.Ownersofvulnerablebuildings
shouldseismicallyretrofittheirbuildingforstructural,fire,usabilityandfallinghazardsbyspecificdeadlines,varyingbybuildingcategory.
pageXX
5. Assistcommunityservicegroupstoreachearthquakeresilience.TheCity
shouldprovidetechnicalandfinancialassistanceforimportantnon‐profitorganizations,medicalclinics,daycares,housesofworshipandsimilarorganizationstoseismicallyretrofittheirbuildingsorimprovetheirearthquake
resilienceinotherways.
pageXX
6. Clarifyresponsibilityforpreparingforandreducingriskfromearthquakes.TheCityshouldidentifyasingleofficial,the“EarthquakeCzar”,tobe
responsibleforachievingearthquakeresiliencethroughmitigation,responseandrecovery.
pageXX
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7. Adoptimprovedpost‐earthquakerepairstandards.TheCityshouldenactupdatedpost‐earthquakerepairandretrofitstandardsdevelopedbyCAPSS
andexpandthisapproachtootherbuildingtypes.
pageXX
8. Offerincentivesforretrofitofbuildings.TheCityshouldenactarangeofmeaningfulprogramstohelpbuildingownersaffordretrofits.
pageXX
9. Requiregasshut‐offvalvesonselectbuildings.TheCityshouldrequireownersofcertainvulnerablebuildingsandbuildingsinFireDepartmentdesignatedPost‐EarthquakeHighFireHazardAreastoinstallautomaticgas
shutoffvalves.
pageXX
10. Trackevaluationsandretrofitsinadatabasesystem.TheCityshouldincludeinformationrelatingtoseismicevaluationsandretrofitsinDBI’supdated
databasesystemtoallowtrackingprogressofmitigationactivitiesandrecordinginventories,evaluationreportsandretrofitinformation.
pageXX
11. Providetechnicalassistanceforbuildingretrofits.TheCityshouldhelpresidentsandbuildingprofessionalstoevaluateandseismicallyretrofitbuildingsefficientlyandinaccordancewithCitycodes.
pageXX
12. Enactafaçadeordinance,requiringperiodicinspectionoffaçades,parapetsanddecorativefeaturesfixedtobuildingexteriors,andrequirerepairofmaterialsfoundtobefallinghazards.
pageXX
13. Promotedevelopmentandimplementationofeffectiveideasonearthquake
riskreduction.TheCityshouldencourageeffortstoimproveknowledgeaboutbuildingstructuralperformanceandeffectivewaystoreduceearthquakerisk
thatarerelevanttoSanFrancisco.
pageXX
14. Evaluatemeasurestoreducepost‐earthquakefires.MultipleCityDepartmentsshouldworktogethertoevaluateandimplementmeasuresto
reducefireignitionsandspread,andimprovefiresuppressioncapacityfollowingearthquakes.
pageXX
15. Addressthehazardsfromdamagetofurnishings,appliancesandequipmentandnon‐structuralbuildingelements.DBIshouldinitiateacomprehensiveprogramtoencourage,andinsomeinstances,requiremeasurestoreducethesehazards.
pageXX
16. Periodicallyevaluateprogressandimplementationoftheserecommendations.
pageXX
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Table4‐1.Recommendedactionscategorizedbymitigationobjective.
ObjectiveRecommendedmitigationactions(a) (b) (c) (d) (e)
1. Informthepublicofrisksandwaystoreducerisk. X X X X X
2. Adoptupdatedcodestandards. X X X X X
3. Requireallbuildingstobeevaluatedforseismicrisk. X X X X X
4. Requireretrofitsofvulnerablebuildings. X X X X X
5. Assistcommunityservicegroupstoreachearthquakeresilience. X X
6. Clarifyresponsibilityforpreparingforandreducingriskfromearthquakes.
X X X X X
7. Adoptimprovedpost‐earthquakerepairstandards. X X X X X
8. Offerincentivesforretrofitofbuildings. X X X X X
9. Requiregasshut‐offvalvesonselectbuildings. X X X X X
10. Trackevaluationsandretrofitsinadatabasesystem. X X X X X
11. Providetechnicalassistanceforbuildingretrofits. X X X X X
12. Enactafaçadeordinance. X
13. Promotedevelopmentandimplementationofneweffectiveideasonearthquakeriskreduction.
X X X X X
14. Evaluatemeasurestoreducepost‐earthquakefires. X X X X
15. Addressfurnishingsandnon‐structuralbuildingelements X X X
16. Periodicallyevaluateprogressandimplementationoftheserecommendations.
X X X X X
Mitigationobjectives:
a) Residentswillbeabletostayintheirownhomesb) Residentswillquicklyhaveaccesstoimportantprivately‐runcommunityservicesc) Nobuildingwillcollapsecatastrophicallyd) Businessesandtheeconomywillquicklyreturntofunctionalitye) TheCity’ssense of placewillbepreserved
WorkingDraftCAPSSTask4Report page27
Table4‐2.Recommendedmitigationactionscategorizedbythree‐stepapproach.
Recommendedmitigationactions Step1 Step2 Step3 Other
Facilitatemarketforearthquakeperformance
Evaluation
uponsaleorby
deadline
Retrofit
bydeadline
1. Informthepublicofrisksandwaystoreducerisk. X
2. Adoptupdatedcodestandards. X X
3. Requireallbuildingstobeevaluatedforseismicrisk. X
4. Requireretrofitsofvulnerablebuildings. X
5. Assistcommunityservicegroupstoreachearthquakeresilience.
X
6. Clarifyresponsibilityforpreparingforandreducingriskfromearthquakes.
X
7. Adoptimprovedpost‐earthquakerepairstandards. X
8. Offerincentivesforretrofitofbuildings. X
9. Requiregasshut‐offvalvesonselectbuildings. X
10. Trackevaluationsandretrofitsinadatabasesystem. X X X
11. Providetechnicalassistanceforbuildingretrofits. X
12. Enactafaçadeordinance. X
13. Promotedevelopmentandimplementationofneweffectiveideasonearthquakeriskreduction.
X
14. Evaluatemeasurestoreducepost‐earthquakefires. X
15. Addressfurnishingsandnon‐structuralbuildingelements.
X X X
16. Periodicallyevaluateprogressandimplementationoftheserecommendations.
X
WorkingDraftCAPSSTask4Report page28
Thefirststepinthethree‐stepstrategy(seeprevioussection)istocreateadeeperunderstandingofearthquakeriskandriskreductionmeasures,whichwillunderpinamarketforretrofitting.SanFrancisco
residents,businessesandbuildingownersneedtoknowspecificallywhatriskstheyfaceandwhattodotoreducethoserisks.Ontheirown,educationprogramsmotivateonlyalimitednumberofpeopletotakeaction.However,theyareanessentialpartofmakingotherriskreductionprogramswork.When
usedintandemwithotherprogramsaimedatreducingrisk,educationprogramscanleadtosignificantaction.
Educationandoutreachcampaignsneedtobetargetedatspecificaudiencesandfocusedonparticular
buildingcategoriesandtopicstobeeffective.Programsshouldpresentspecificstepsthatparticulartypesofbuildingowners,tenants,businessowners,constructionprofessionals,andotherscantaketoreduceearthquakeimpacts.SanFranciscansneedtounderstandearthquakeriskinpersonalterms.
Thesecampaignsneedtobelong‐lastingandthemessagesfrequent,andfrommultiplesources.
Citydepartmentscandosomeofthis,andcangettheballrolling,butitiscriticaltocoordinatewithpartnersinthepublicandprivatesectors.Fireandearthquakeinsurancecompanies,utilities,
contractors,andbuildingmaterialsstorescouldbeparticularlyeffectivepartnersthatalsowouldbenefitfrombettercommunityunderstandingoftheseissues.
CAPSSrecommendthefollowingspecificeducationandoutreachprogramsforSanFrancisco:
a) Explaintheneedforandprocesstoevaluatebuildingseismicperformance,includingstructural,fire,andfallinghazards.Thisreportrecommendsrequiringbuildingownerstoevaluatetheseismicperformanceoftheir
buildinguponsaleorascheduleddeadline(recommendation3).Buildingownersandothersthatwouldbeinvolvedinthisprocess(realtors,etc.)needtoknowwhattheyneedtodo,andhowtodoitproperly.Theyshouldalsounderstandwhyevaluationsareimportantandthegoalsbehind
requiringthem.
b) Offercoursesaimedatsingle‐familyhomeownersabouthowtoconductsmallscaleseismic
retrofits.Somesingle‐familyhomescanimprovetheirseismicsafetythroughrelativelysimpleandaffordablesteps.TheCityshoulddevelopacourseforresidentsteachingthemsimplethingstheycandoto
upgradetheirhomes,aswellasclarifyingwhentheyneedtoseekprofessionalhelp.
Recommendation1.Informthepublicofrisksandwaystoreducerisk.TheCityshouldconductfocusededucationandoutreachcampaignsaimedatbuildingowners,tenants,
realtorsandotherstoimprovetheirunderstandingofearthquakerisksandmeasurestomanagetherisk,andtofacilitateamarketforretrofitting.
WorkingDraftCAPSSTask4Report page29
c) Educateinstallers,buildingowners,andothersaboutproperwaystobracewaterheaters.Toppledwaterheatershavefueledearthquake‐triggeredfireinpastearthquakes.Statelawandthe
City’sbuildingcodecurrentlyrequirewaterheatersbestrappedsecurelywhenevertheyarereplaced,orwhenbuildingsintheCityaresold.However,itappearsthatmanywaterheatersinSanFranciscoarestrappedimproperly,meaningtheycouldstillfallandfuelfiresduringanearthquake.
Aprogramtomakesurewaterheaterinstallers,buildingownersandothersknowtheproper,safewaystosecurewaterheaterscouldmakeabigdifferencewithsmallcost.
d) Educateresidentsaboutsimpleandcost‐effectivewaystomaketheirhomessaferandhabitablefollowingearthquakesbyreducingfallinghazards.Fallinghazards,suchasfurnituretopplingorceilingfixturesfalling,causeseriousproblemsinevery
earthquake,includingdeaths,increasedeconomiclosses,andmakingbuildingspaceunusable.Itisoftensimpleandinexpensivetoreducetheriskofcasualtiesanddamagefromfallinghazards.TheCityshouldconductaneducationcampaigninformingresidentsaboutspecificstepstheyshould
take,andincludedetailssuchastypesofhardwaretopurchaseandhowtoinstallit.
e) DevelopaprogramincoordinationwithotherCityagenciestoworkwithsmallbusinessesand
importantcommunityserviceprovidersonmeasurestheycantaketoreducevulnerabilitytoearthquakes.Smallbusinessesandimportantcommunityservices,suchasnon‐profitorganizationsthatservethe
dailyneedsoftheCity’smostvulnerableresidents,areimportanttotheCity’srecoveryfromfutureearthquakes.Byreducingriskandplanninginadvance,theseorganizationscangreatlyimprovetheir
abilitytostayafloatandcontinuetofunctionafteranearthquake.TheCityshouldencourageandhelporganizationstodevelopmitigationandrecoveryplans.
f) Encouragebuildingmaterialsstores,insurancecompaniesandutilitycompaniestosupplementeducationcampaigns.Buildingmaterialsstores,insurancecompaniesandutilitycompaniesregularlycontactbuilding
ownersandmanagers,andcouldprovideSanFranciscospecificinformationaboutreducingearthquakevulnerabilityandactionstotakeafterearthquakes.Thesecompanieshaveadirectinterestinreducingearthquakedamageandpostearthquakefire,andshouldadvisebuilding
ownersaccordingly.Multiple,consistenteducationmessagesfromavarietyofpublicandprivateentitiesarefarmorelikelytoleadtoactionthanisolatedmessagesonlyfromgovernmentagencies.
g) Revisepost‐earthquakebuildinginspectionprotocolsandtraininspectorsandownerstoidentifybuildingsthatcanbeoccupiedsafelydespitedamageandlossofutilities.Afteranearthquake,itbenefitseveryonetoallowasmanyresidentsandbusinessestoremainin
theirbuildingsaspossible,whileensuringsafetyduringaftershocks.Displacingresidentsandbusinessesmakesrecoverymoredifficult.Inspectorswhoconductpost‐earthquakesafetytaggingshouldbetrainedinpost‐earthquakeoccupancyconcernsparticulartoSanFrancisco.Many
buildingswillbeinspectedandevaluatedbytheiroccupants,whichmeansthatpublicinformationcampaignsaboutthisissueimmediatelyafteranearthquakewillplayanimportantrole.
WorkingDraftCAPSSTask4Report page30
h) TrainpreservationengineersandarchitectsknowledgeableaboutSanFrancisco’shistoric
resourcesinpost‐earthquakesafetytagging.SanFrancisco’sbuildingstockisuniqueandbeautiful.Toensurethatitstaysthatway,theCityshouldmakesurethatengineersandarchitectsthatareknowledgeableaboutpreservationissues
areinvolvedinpost‐earthquakebuildingsafetyevaluationsandtagging.Thetaggingprocessoccursimmediatelyafteranearthquakeandinfluencesrepairanddemolitiondecisions.Historicresourceissuesmustbeconsideredinthesedecisions.TheCityshouldconductoutreachtothepreservation
communitytomakesurethattheyaretrainedtoassistinthisprocess.
WorkingDraftCAPSSTask4Report page31
DBIshouldadoptbuildingcodestandardstobeusedasabasisfordeterminingvulnerabilityandseismicretrofittingrequirements.AstheCitymovesforwardwithprogramstoencourageandrequiremore
retrofitsofvulnerablebuildings,itiscriticalforDBItoadoptupdatedcodestandardsthatreflectboththeCity’searthquakeresilienceobjectivesandtechnicaladvancesinstructuralengineering.
TheCityshoulddefinewhatperformanceitexpectsduringearthquakesforallexistingandnew
buildings,consideringpost‐earthquakeusabilityandsafety.Retrofitstandardsshouldreflecttheseperformancegoals.Retrofitstandardsshouldrelatetobothabuilding’sstructuretypeandhowitisused,becausebuildinguseisakeyfactorindeterminingwhatlevelofdamageinearthquakesisdeemed
acceptablebysociety.DBIshouldseektoadoptretrofitstandardsthattakeapractical,optimalapproach.Thestandardsshouldoptimizeperformanceimprovementswhileminimizingintrusionintooccupiedspacesandthecostofretrofits.Forsometypesofbuildings,achieving“shelter‐in‐place”
performance,orevenreparability,mightbeunacceptablyexpensiveorintrusive,makinglowerperformanceexpectationsreasonable.
Duringthisprocess,theDepartmentshoulddevelopaclearunderstandingoftheperformanceexpected
fromnewbuildingsconstructedtothecurrentbuildingcode,andconsiderwhetherimprovementsarenecessary.SuperiorperformanceisneededfromnewconstructionfortheCitytoachieveitsresilienceobjectivesforhousingandbusinesses.
TheCityalsoshoulddefinestandardsandproceduresforengineeringevaluationsofseismic
performanceforallbuildingtypescommoninSanFrancisco.Recommendation3inthisreportrecommendsrequiringbuildingownerstoevaluatetheseismicvulnerabilityoftheirbuildinguponsaleorascheduleddeadline.Beforethiscanhappen,DBIneedstoadaptandadoptclearguidelinesand
technicalstandardsforprofessionalstouseforevaluationsofstructuresofdifferenttypesandforcommunicatingthefindingsinmeaningfulandobjectivetermsrelativetostandards.Forcommonbuildingtypes,itwouldbeidealifinspectorscoulduseasimplechecklistapproachthatrequiresa
minimumofcomplexcalculations.DBIshouldalsoworktodevelopascheme,suchasabuildingratingscheme,toexplainthefindingsofthestructuralevaluationstonon‐technicalbuildingownersandusersinameaningfulwaysthatcanhelpthemmakedecisionsaboutbuying,rentingorretrofitting7.The
informationprovidedshouldbeclearthatbuildingswithidentifiedvulnerabilitiesmightbeperformbetterthanbuildingsthathavenotbeenevaluated.
7Asanexample,theStructuralEngineersAssociationofNorthernCalifornia(SEAONC)isdevelopingaschemetoassignstarstobuildings,ratingthreecharacteristics:safety,repaircost,andtimetoreoccupy.Afterevaluation,buildingswouldbeassignedfromzerotofivestars,indicatinggoodorbadseismiccharacteristics(Stillwell,2010).Otherschemesmaybeavailable,aswell.
Recommendation2.Adoptupdatedcodestandards.TheCityshouldadoptcodestandardsforseismicevaluationandretrofitofallcommonbuildingtypesinSanFrancisco.
WorkingDraftCAPSSTask4Report page32
CAPSSrecommendsthefollowinggeneralperformanceobjectivesforSanFranciscocodestandards:
• Retrofitstandardsshouldresultinmostresidentialbuildingsbeingsafeforuseafter
earthquakesandduringtheiraftershocks(thisperformancelevelcanbereferredtoas“shelter‐in‐place”).Utilities—water,sewer,power,etc.—maynotbefunctional,whichwouldinfluencewhetheroccupantschoosetoremaininthesebuildings.SanFranciscoPlanningandUrban
Research(SPUR)hasproposedagoalthat95percentofSanFranciscansshouldbeabletoshelter‐in‐placefollowingalarge,“expected”earthquake.
• Retrofitstandardsforbuildingsthatcannotreasonablymeettheshelter‐in‐placestandardshouldresultinbuildingsthatcanberepaired.ReparabilityprotectsSanFrancisco’scommunities,sense‐of‐place,historicresourcesandaffordablehousing.
• Retrofitstandardsforbuildingtypesthatcannotreasonablymeeteithertheshelter‐in‐placeor
reparabilitystandards,asaminimum,mustpreventcollapseanddangertooccupants.
Regardlessofthestructuralperformancestandard,allretrofitstandardsshouldalsoincludemeasurestoaddressthefollowingissues:buildingelementssuchasstairsandelevatorsthataffecttheusabilityofbuildings;fallinghazards,suchasoverheadpiping,andequipmentandfurnishings,thataffectsafety;
andfireignitionsourcesandconditionsthatcouldencouragefirespread.Standardsshouldrequirelargebuildingstoaddressgroundfailureriskswhenundergoingretrofits.
DBIshouldspecifybenchmarkcodedatesforallsignificantbuildingstructuretypes.Buildings
constructedorretrofittedafterthesebenchmarkdateswouldbepresumedtohaveadequateearthquakeresistance.Forbuildingsconstructedorretrofittedtoearliercodes,standardsdesignatedby
DBIwouldsetthebasicretrofitstandard.Currently,DBIhasonebenchmarkcodedateforallstructuretypes—May21,1973—althoughitisclearthatsomebuildingtypesconstructedorretrofittedafterthatdatehaveseismicvulnerabilities.
DBIshouldamendSection3403.5ofthecodetoimproveitasnewinformationandstandardsbecomeavailable.Inparticular,DBIshouldseekstandardsthatreflectadvancesinstructuralengineeringapproachesandconsiderbuildingflexibilityinadditiontostrength.Someperformance‐basednational
standardsarenowreferencedinbuildingcodesandarewidelyusedhereandabroad,suchasASCE31forevaluationsandASCE41forretrofits(ASCE,2007).Thesestandardshaveknownlimitationsatthistime,butshouldbecomeincreasinglypracticalforuseincomingyears.These“nextgeneration”code
standardspotentiallyallowmoreeffectiveretrofitsatlowercosts.
WorkingDraftCAPSSTask4Report page33
Thisisthesecondstepinthethree‐stepstrategy.PeoplewhoownandusebuildingsinSanFrancisco
shouldknowwhethertheirbuildingislikelytobesafeduringfutureearthquakes,andrepairableand/orusableafterthoseearthquakes.Thisinformationallowsprospectivebuyersandtenantstoconsiderseismicissueswhenmakingdecisionsaboutpurchasingorrentingspace.Itprovidesinformationneeded
toincorporateseismicissuesinmarketpricingofrealestate.Itwouldalsoprovideownerswiththeinformationneededtodecidewhethertoseismicallyretrofitvulnerablebuildings.
ThisrequirementshouldbeenactedonlyafterDBIhasadoptedupdatedcodestandardsforseismic
evaluationandretrofits(recommendation2).Theinformationprovidedshouldbeobjectiveandmeasuredagainsttheestablishedstandards.BuildingownerswhochoosetovoluntarilyretrofittoDBIstandardsafterdiscoveringthroughanevaluationthattheirbuildinghasseismicvulnerabilities,should
beexemptedfromretrofitmandatesforaperiodof15years.
Findingsoftheevaluationshouldbesharedwithexistingtenantsandprospectivebuyersandtenantsandavailableinpublicrecords.Thefindingsshouldbeincludedinthe3Rreportforresidentialbuildings
anddisclosedtointerestedparties.Thisevaluationshouldbeconductedbylicenseddesignprofessionals,alongwithotherinspectionstypicallyconductedbylicensedpersonnelatthetimeofsale.
Evaluationresultsshouldbepresentedinawaythatmakesitclearthatevaluatedbuildingsarenot
regardedasmorevulnerablethanbuildingsthathavenotbeenevaluated.Buildingsnotyetevaluatedarepotentiallyhazardous.
Theevaluationsshouldcovermanyaspectsofbuildingseismicrisk,inadditiontoassessingwhethera
building’sstructuremeetstheadoptedDBIretrofitstandards:
• Evaluationsshouldidentifybuildingswithweaknessesthatcouldleadtocollapseandlifeloss.
• Evaluationsshouldexplicitlyexaminebuildingmaterialsfordeteriorationduetowaterintrusion
orpestinfestationandweaknessintheattachmentofcladdinganddecorativeelements.
• Geotechnicalevaluationsshouldbeconductedforlargebuildingslocatedinareasdesignatedas
havingahighpotentialforliquefaction‐inducedgroundfailure.
Recommendation3.Requireallbuildingstobeevaluatedforseismicrisk.Ownersofallbuildingsshouldevaluatetheseismicperformanceoftheirbuildingsuponsalerelativeto
standardsadoptedbyDBIor,ifnosaleoccurs,byadeadlineestablishedbasedonthebuildinguseandstructuraltype.Theresultwouldbesharedwithtenantsandprospectivebuyersandtenants,andbemadeapartofpublicCityrecords.
WorkingDraftCAPSSTask4Report page34
• Evaluationsshouldidentifyfireignitionandspreadrisks,suchaswhetherwaterheatersareproperlysecured;whetherelectricalwiring,gaspiping,appliancesandmetersareproperly
installed;thepresenceofunauthorizedperforationsinfirewalls;andwhetherabuildingislocatedinanareapronetoconflagration(definingtheseareas,designatedasPost‐EarthquakeFireHazardArea,isdiscussedinrecommendation9).
• Evaluationsshouldidentifyissuesthataffectpost‐earthquakeusabilityandsafety.Thereare
various“non‐structural”aspectsofbuildingsthataffectthesafety,usabilityandreparabilityof
buildings.Damagedpartitionwalls,equipment,furnishings,elevatorsandutilitiescanhurtpeople,ignitefires,orpreventoccupancyandbusinessresumption.
Deadlinesforevaluationsshouldbeestablishedforbuildingtypesthatsellrarely,orthosedividedinto
multipleparcelsthatsellatdifferenttimes(e.g.,condominiums),withprioritygiventobuildingsthatmaybeunsafe.Ownersofmanybuildings,suchasauniversityorinstitutionalinvestor,couldsubmitaprogramtoDBIshowinghowtheirentirebuildingstockwillbeaddressed,reflectingtheirinternal
prioritiesandfacilitymanagementneeds,andbeallowedflexibilitywithintheCity’sdeadlinesbybuildingtype.RecommendedbuildingcategoriesandassociateddeadlinesappearinthenextsectionBuildingCategoriesandDeadlines.
Aspartofthisprocess,largerbuildingscouldberequiredtoparticipateintheBuildingOccupancyResumptionProgram(BORP).BORPisaCityprogramthatallowsbuildingownerstoengageanengineerbeforeanearthquaketoinspecttheirbuildingfordamageafteranearthquake.Itcanexpedite
reoccupancyafteranearthquake.
WorkingDraftCAPSSTask4Report page35
SanFranciscoisaCitypronetoearthquakeswithanoldandvulnerablestockofbuildings.Asdiscussed
inotherrecommendations,theCityneedstoofferstrongeducationandincentiveprogramsandrequireseismicevaluationsofbuildings.Allofthesestepswillencouragebuildingownerstoseismicallyretrofitvoluntarily.However,itislikelythatmostownerswillnotretrofittheirbuildingsunlesstheyare
requiredtodoso.Ultimately,theCitywillneedtoownersofrequirevulnerablebuildingstoretrofittoimproveSanFrancisco’searthquakeresilience.Thisisthethird,andlast,stepinthethree‐stepprocess(seeXXX),andwastheapproachusedtoaddressunreinforcedmasonrybuildingsduringthe1990’s.
DeadlinesformandatoryretrofitsshowthattheCitybelievesthisissueisserious,allowsthemarkettoconsiderseismicsafetyinitspricing,andprovidescertaintyforownersofvulnerablebuildingstoplanforthefuture.TheCityshoulddefineanumberofbuildingcategories,basedonbuildinguseand
structuralsystem,andsetaseriesofstaggereddeadlinesforrequiringretrofits.Someofthesedeadlinesshouldbesoon;othersshouldbedecadesaway.Deadlinesshouldbeassignedtovariousbuildingcategoriesbasedonbuildingrisk,importancetocommunityresilience,andfeasibilityandcostof
retrofits.Again,ownersofmanybuildings,suchasauniversityorinstitutionalinvestor,couldsubmitaprogramtoDBIshowinghowtheirentirebuildingstockwillbeaddressed,reflectingtheirinternalprioritiesandfacilitymanagementneeds,andbeallowedflexibilitywithintheCity’sdeadlinesby
buildingtype.
RecommendedbuildingcategoriesandassociateddeadlinesappearinthefollowingsectionCategoriesandDeadlines).Retrofitsshouldaddressstructuraldamage,firerisk,fallinghazards,usabilityconcerns
and,forlargerbuildings,geotechnicalconcernsthatwereidentifiedinevaluations(recommendation3).
Recommendation4.Requireretrofitsofvulnerablebuildings.Ownersofvulnerablebuildingsshouldseismicallyretrofittheirbuildingforstructural,fire,usabilityandfallinghazardsbyspecificdeadlines,varyingbybuildingcategory.
WorkingDraftCAPSSTask4Report page36
SanFranciscoisprivilegedtohavemanynon‐profitorganizationsthatservethedailyneedsoftheCity’smostvulnerableresidents—itspoor,elderly,children,disabled,andnon‐nativeEnglishspeakers.After
anearthquake,vulnerableresidentswillneedservicesfromthesegroupsmorethanever.Manyoftheseorganizationsoccupyrentedspaceandarenotincontrolofbuildingmaintenanceissuesorseismicsafetyconcerns.TheCitydepartmentsthatworkwiththesegroupsshoulddevelopaprogramtoassist
them,technicallyandfinancially,toevaluatetheseismicsafetyofthebuildingstheyuseandtoretrofitvulnerablebuildingsorrelocatetobetterbuildings.
TheCityshouldprovidespecialassistancetothefollowingtypesoforganizations:
• Non‐profitsprovidingimportantservicestovulnerablepopulations
Theseprovidersservethehomeless,personsconfinedtotheirhomesduetohealthordisabilities,personswithmedicalorpsychologicalissues,thepoorandothers.ManyCityagenciesusetheseorganizationstodeliverservices.TensofthousandsofSanFranciscansrely
ontheseorganizationsforservicesthatkeepthemalive.
• PreschoolsanddaycarecentersChildreninpreschoolanddaycarecentersshouldbesafeinearthquakes,justastheirolder
siblingsareinpublicschools.Moreover,parentsrelyonthesefacilitiestocarefortheirchildrenwhiletheywork.SanFrancisco’srecoveryfollowingearthquakesdependsonpeoplereturningtowork.
• ClinicsandfacilitiesprovidingurgentandcriticalmedicalservicesNeighborhoodurgentcareandpsychologicalclinics,dialysiscenters,medicalsuppliers,andhospitalfacilitiesnotregulatedbytheStateofCalifornia8providecriticalservicestoSan
Franciscans.Theseserviceswouldbeneededtotreatthethousandsofinjuriesthatdonotrequirehospitalizationimmediatelyafterearthquakes,andinthedays,weeksandmonthsthatfollow.
• Placesofworship
8AstatelawreferredtoasSB1953requiresownersofacutecarehospitalstoevaluatetheirfacilitiesandmeetspecifieddeadlinestoretrofitorreplacevulnerablefacilities.
Recommendation5.Assistcommunityservicegroupstoreachearthquakeresilience.TheCityshouldprovidetechnicalandfinancialassistanceforimportantnon‐profitorganizations,medicalclinics,daycares,housesofworshipandsimilarorganizationstoseismicallyretrofit
theirbuildingsorimprovetheirearthquakeresilienceinotherways.
WorkingDraftCAPSSTask4Report page37
Churches,temples,mosquesandotherreligiousbuildingshavelargeoccupanciesduringservices.Theyalsoprovidecriticalservicestothebroadercommunity.Thesebuildingsoften
haveearthquakevulnerabilitiesduetotheirsize,configuration,ageandfallinghazards.Duringearthquakestheyposeseriousthreatstothesafetyofoccupants,andtheresultingdamagewouldlimittheirabilitytoprovideservicestothecommunity.
WorkingDraftCAPSSTask4Report page38
ImplementingearthquakemitigationmeasuresneedstobecomeanongoingconcernoftheCitywith
standingequaltootherprograms.TheearthquakeprogramswithintheCityneedtobeinstitutionalizedandresponsibilityforimplementationclarifiedsothatthelong‐termeffortrequiredwillnotwaneaspeopleretireandotherissuesemerge.Itshouldbetheresponsibilityofonehighlevelofficialwithinthe
ChiefAdministrativeOfficer’sofficewhohastheabilitytoworkwithmanydepartmentsandisaccountableforachievingprogress.TheresponsiblemanagermightbecalledtheEarthquake Czar.
Theofficialwouldmonitorprogressincarryingouttherecommendationsinthisreportwithinthe
responsibleCityagenciesandwouldmakepublicquarterlyreportstotheDisasterCouncil.Ideally,thisfunctionwouldbeestablishedintheCityCharter.
Overseeingtheinterrelatedyetautonomousdepartmentsresponsibleforearthquakemitigation,
preparedness,responseandrecoveryatthehighestadministrativelevelisnecessaryandtheresponsibilitiesshouldbeexplicitlydescribed.ThemeasuresneededtoimprovetheearthquakeperformanceoftheCityarephysical,involvingprivateandgovernmentbuildingsandutilities,
preparationofpeopleandorganizations,andmanydepartments,commissionsandboards(includingtheDepartmentsofBuildingInspection,Planning,EmergencyManagement,PublicWorksandFire,andfunctionssuchasfacilitiesmanagementandcapitalplanning,etc.).Theofficeshouldseekappointment
ofaMayoraltaskforcetoinvestigateanumberoftherecommendedactionsandtofocusagenciesonreducingandmanagingearthquakerisk.
Theofficialshouldworkwithanadvisorycommittee,whichwouldmeetperiodicallytoreviewprogress
implementingtherecommendationsinthisreportandtoadviseonwaystoimprovetheprogram.Thepreparationoftherecommendationsinthisreportbenefitedfromanactiveanddedicatedadvisorycommittee.Theinsightsandconcernsofrepresentativesofvariousinterestandneighborhoodgroups
providevaluableperspectiveandimproveaccountabilityforperformanceandprogress.
ThisofficewouldalsosupportprivatesectoreffortsbyprovidinganombudspersontohelpownersnavigatethroughCityrequirementsandprogramsrelatingtoretrofitting.NavigatingCityrequirements
canbechallenging.Adedicatedastaffcouldhelpbuildingownersandconstructionanddesignprofessionalsmeetallrequirementsrelatingtoseismicsafetyandtakeadvantageofallincentiveprograms.Thisombudspersonofficeshouldhaveemployeesknowledgeableaboutprogramsand
requirementsacrossthemanyCitydepartmentsthataddresstheseissues.Anombudspersonwhoreachesouttoowners,providestrainingandinstructionsandhelpsshepherdprojectsthroughtheentireprocesscouldfacilitatewidespreadretrofitting.Theombudspersonshouldunderstandboth
economicandtechnicalissuesandbesupportedadministrativelyandnotconflictedwithotherresponsibilities.
Recommendation6.Clarifyresponsibilityforpreparingforandreducingriskfromearthquakes.TheCityshouldidentifyasingleofficial,the“EarthquakeCzar”,toberesponsibleforachievingearthquakeresiliencethroughmitigation,responseandrecovery.
WorkingDraftCAPSSTask4Report page39
Afteranearthquake,somedamagedbuildingscanberepairedtothewaytheywerebeforetheearthquake.Otherdamagedbuildingsneedtoincorporateseismicretrofitsintotheirrepairs,toensurethattheysufferlessdamageinfutureearthquakes.TheCity’scurrentpolicytodefinewhichbuildings
needtoretrofit,andwhichcanonlyrepair,needsimprovement,asevidencedbyproblemsexperiencedafterthe1989LomaPrietaearthquake.Apost‐earthquakerepairandretrofitpolicyisarequirementtoreceivecertaintypesofpost‐disasterfundingfromtheFederalEmergencyManagementAgency.
Inacompanionreport(ATC52‐4,Postearthquake Repair and Retrofit Requirements),CAPSShasdevelopedclarifiedtechnicalrecommendationstoimprovethispolicyandtoimprovethewaythisprocessbuildstheCity’sresilienceovertime.TheCityshouldadopttheserevisedprovisions.
CAPSShasdevelopeddetailedrecommendationsthatcover95percentoftheCity’sbuildings.DBIshouldusethisworkasamodeltodevelopdetailedimprovementsforadditionalstructuretypesidentifiedintheCAPSSreport.
Recommendation7.Adoptimprovedpost‐earthquakerepairstandards.TheCityshouldenactupdatedpost‐earthquakerepairandretrofitstandardsdevelopedbyCAPSSandexpand
thisapproachtootherbuildingtypes.
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Ownersultimatelyareresponsiblefortheearthquakeperformanceoftheirbuildings:theyhavethemosttogainfromimprovedperformance,andthemosttolosebecauseofdamageandliability.Buildingownersbenefitbyretrofittingbeforeearthquakesstrike,buttheupfrontcostsaresignificantand
conflictwithotherexpenditurepriorities.Whileretrofittingresultsinasafer,morereliablebuildingwithitsvaluebetterprotectedfromearthquakedamage,oftenthereisnomoreuseablespaceoroperatingefficiencyachieved,andimprovedseismicsafetymaynotbereflectedinmarketvaluesorrental
incomes.However,theCityhasastronginterestinreducingtheamountofdamagethatoccurstoprivately‐ownedbuildingsinfutureearthquakes.LessdamagemeansaquickerandlesscostlyrecoveryfortheentireCity,aswellasreducedsocialdislocation.Theconsequencesofcumulativedamageto
privately‐ownedbuildingsforneighborhoods,localbusinesses,historiccharacter,andpostearthquakehousingavailabilityandaffordabilitymakeprivatedamageapublicconcern.Therefore,itmakessensefortheCitytoinvestinencouragingbuildingownerstomaketheirbuildingssafer.
Itisimperativethatagenciesdevelopandoffermeaningfulincentiveswithinthenextyear.IncentivesareanimportantcomponentofStep1ofthethree‐stepstrategy(seeprevioussection)toencourageownerstoretrofit.Whileincentiveswillnotleadtomostbuildingsownersretrofittingtheirbuildings,
theycouldmakethedifferenceforsomeownerswhoarealreadyinclinedtoretrofitandwillcombinewithotherprogramstoleadtomoreaction.TheyalsosendapositivesignaltobuildingownersthattheCitydoesnotexpectthemtosolvethisproblemontheirown.
Differentincentivesaremeaningfulfordifferentowners,sotheCityshouldofferavarietyofapproaches.IncentivesthatwouldencourageandfacilitateretrofittinginSanFranciscoarethefollowing:
a) ThePlanningCodeandotherCitystatutesandregulationsshouldbeamendedtoofferincentivestobuildingownerswhovoluntarilyconductseismicretrofitstomakechangestotheirbuildingsthatwouldincreasetheirvalue.
TheCityhastheabilitytoofferanumberofnon‐financialincentivesthatproviderealvaluetobuildingowners.Theseincludeallowingadditionalunitsoruses(densitybonuses),allowingretrofitstoencroachintosetbacks,increasedfloor/arearatios,relaxationofparkingrequirements,changein
heightlimits,transferofdevelopmentrights,andpriorityinthecondominiumconversionlottery.Theseissueswouldallowbuildingownerstomakechangestotheirbuildingtoincreasetheirvalue.WhilenotcostingtheCityanythingintermsofdollars,theseplanningandzoningissuesimpact
othervaluesandcaninspirestrongfeelingsamongCityresidents.TheCityshouldengagerelevantdepartments,Cityresidentsandbuildingownerstodiscusswhichofthesepotentialincentivesprovidemeaningfulmotivationtobuildingownerstoretrofit,andwhethertheirshort‐termsocial
Recommendation8.Offerincentivesforretrofitofbuildings.TheCityshouldenactarangeofmeaningfulprogramstohelpbuildingownersaffordretrofits.
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implicationsoutweighthelong‐termsocialbenefitsthatcomefromimprovedseismicperformance.ExistingpoliciesprotectvaluesimportanttotheCity,suchashousingaffordabilityanddensityof
uses.However,thesevaluesarethreatenedbyinevitableearthquakedamagefarmorethanchangesmadeduringretrofits.Incentivesforearthquakeretrofitswouldprotectthesevalueslong‐term,noterodethem.
b) Maintainfeewaiversandexpeditedreviewforvoluntaryseismicretrofitsofvulnerablewood
frameresidentialbuildings.
In2009,SanFranciscobeganofferingexpeditedplanreviewandsomefeewaiversforownerswhodecidetoretrofitvulnerablewoodframeresidentialbuildings.Damagetowoodframebuildingswillberesponsibleformostofthehousingunitsthatcannotbeoccupiedafterfuturelargeearthquakes.
Itmakessensetocontinuethismodestprogramtoencouragebuildingownerstoinvesttheirownresourcestoretrofitthesevulnerablebuildings.
c) Adoptapolicythatassuresthatthosewhovoluntarilyretrofittoappropriatestandardswouldnotberequiredtodomoreworkfor15years,evenifstandardschange.OwnerswhoundertakeretrofittingtotheCity’sstandardswantsomeassurancethattheCitywill
notrequireadditionalretrofitmeasuresascodeschangeandknowledgeofearthquakeperformanceadvances.TheCityhasacurrentpolicythatappliestoretrofittedunreinforcedmasonrybuildings,whichshouldbeextendedtoalltypesofbuildings.Providinga15‐yearperiodin
whichfurtherretrofitswouldnotberequiredwouldencourageownerstoretrofitratherthanwait,andassurelendersthatadditionalfundswouldnotbeneeded.
d) Publicizehowtousetherecentlypassedtransfertaxrebateforseismicsafetyupgrades.
SanFranciscovoterspassedPropositionNinNovember2008.Thisallowsuptoa1/3rdrebateof
transfertaxuponsaletoownerswhohaveseismicallyretrofitted.Fewresidentsknowaboutthisrebateorhowtouseit.TheCityshouldpublicizehowtousethisexistingincentive.
e) Publicizeandfacilitatetheprocessforbuildingownerstomakesurethatseismicretrofitworkisexemptedfrompropertyreassessments.Thisincentivehasbeenstatelawfortwentyyears,butmanyownersdonotknowaboutitorhowto
applyforthiscreditwhenpropertiesarereassessedafterrenovations.TheCityshouldclarifytheprocesstoensurethatseismicworkisnotconsideredinpropertyreassessmentsafterupgrades.
f) ChangethePlanningCodetopreventownersofbuildingsdemolishedafteranearthquakefromrebuildingtopriornonconformingconditions,unlessthebuildingwasseismicallyretrofittedbeforetheearthquake.
Currently,ifabuildingisdemolishedfollowinganearthquake,theownercanrebuildincorporatingnonconformingconditionsthatexistedinthebuildingpreviouslyatthatsite(e.g.,footprint,numberofunits,parking,etc.).Thispolicyshouldbechangedsothatbuildingownershaveanincentiveto
retrofit.
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g) Review,extendanddocumentasappropriatedesignatedHistoricDistrictsandhistoricbuildingsandconductearthquakevulnerabilityassessments.
Ownersofdesignatedbuildingswhoinvestinrehabilitationprojectscanqualifyforfederalincometaxincentives.Becauseearthquakesthreatenthepreservationofirreplaceablehistoricresources,theHistoricPreservationCommissionshouldencouragevulnerabilityassessmentsandmeasuresto
improvetheearthquakeperformanceofhistoricresourcebuildings.TheHistoricPreservationCommissionshouldseekfundstoconductrapidvisualscreeningforearthquakevulnerabilityofdesignatedhistoricresourcebuildingsandbuildingslocatedwithindesignatedhistoricdistricts,and
thenworkwithbuildingownerstoencourageretrofitting.
h) Provideneed‐basedloansforqualifiedretrofits.
Manyownerslacktheassetsorcashflowtoqualifyforcommercialloanstofinanceretrofitting.TheCitycouldhelpbyofferingconventionalordeferredloans.Forconventionalloans,theCitycouldcreateanopt‐indistrictthatwouldusetheproceedsoftaxadvantagedbondstolendtoresidential
buildingowners,includingsinglefamilydwellingowners,thefundsneededtoretrofittotheCity’sstandard.Theloanswouldbepaidbackwithinterestthoughannualpropertytaxcollections.Fordeferredloans,theCitycouldraisefundsthroughthesaleofageneralobligationbondtolendfunds
neededtoretrofitbuildingsthatwouldnotbepaidbackuntilthebuildingissoldorrefinanced.
i) Advocateforfederalandstateincentives.
TheCitycouldadvocateforfederalandstateincentivessuchastaxcreditsanddepreciationschedulestoreduceowners’costsandlessenfederalandstatecostsfollowingearthquakes.The
statealsocouldrequirehomeownerandcondominiumassociationstoincludeinfacilityplansprovisionsforeitherrepairingearthquakedamageorforretrofittingvulnerabilities.
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Inpastearthquakes,gasleakshaveplayedasignificantroleinfuelingpost‐earthquakefires.Gasappliancescanbreakawayfromconnectionsandbuildingdamagecansevergaslines.SanFranciscoisadenselypackedCitywithmostlywoodframe,flammablebuildings,makingpost‐earthquakefireriska
seriousconcern.
Automaticgasshutoffvalves,eithertriggeredbyshakingorexcessflow,canplayaroleinreducingthisfirerisk.Buildingsthatarefoundthroughseismicevaluationtobeparticularlyvulnerableshouldbe
requiredtoinstallautomaticgasshutoffvalves.Inaddition,theFireDepartment,workingwithDBI,shouldidentifylocationswherefireriskisparticularlyhighandwhereshutoffvalveswouldberequired.TheseareaswouldbecalledPost‐EarthquakeHighFireHazardAreas.
Whilegasshutoffvalvesreducefirerisk,theyincreasesomesocialrisksbecauseitcantakealongtimetogetallgaslinesrestartedafteranearthquake.Ifshutoffvalveswereinstalledonallbuildings,manyresidentsinbuildingswithlittledamagecouldbeleftwithoutheat,hotwater,orcookingfacilitiesforan
extendedperiodafteranearthquake.ThiscouldbedeadlytotheCity’slargeelderlyanddisabledpopulations,whichiswhythisreportonlyrecommendsshutoffvalvesforbuildingsmostatriskoffuelingfires.Requirementsforshutoffvalvesshouldbecoordinatedwithsocialserviceagenciessothat
theneedsofdependentpersonsareaddressed.
Recommendation9.Requiregasshut‐offvalvesonselectbuildings.TheCityshouldrequireownersofcertainvulnerablebuildingsandbuildingsinFireDepartmentdesignatedPost‐
EarthquakeHighFireHazardAreastoinstallautomaticgasshutoffvalves.
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DBIisintheprocessofinstallinganupdateddatabasesystem.Thissystemshouldincludearangeof
informationtosupportearthquakeriskreductionprograms,suchasthefollowing:
• Informationaboutbuildinguse• Whetherandwhenbuildingshaveundergoneseismicretrofits,andtowhatstandardabuilding
wasretrofitted• Buildingstructuraltypeandcharacteristicsthataffectvulnerability• Thefindingsofbuildingseismicevaluations
DBI’scurrentdatabasesystemdoesnotincludeinformationaboutseismicretrofitsorvulnerabilityandcannotaggregateandmanipulateinformationforevaluationandtrackingcitywideprogressofmitigationprograms.
Recommendation10.Trackevaluationsandretrofitsinadatabasesystem.TheCityshouldincludeinformationrelatingtoseismicevaluationsandretrofitsinDBI’supdateddatabasesystemtoallowtrackingprogressofmitigationactivitiesandrecordinginventories,evaluation
reportsandretrofitinformation.
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Trainingprogramsandothertechnicalassistancecanhelpmakeretrofittingeasierandcontributeto
high‐qualitywork.Thefollowingtypesoftechnicalassistanceactivitieswouldencourageretrofitting:
a) DevelopstandardplansetsforretrofitsoftypicalSanFranciscobuildings.
ManyofSanFrancisco’sbuildingsaresimilarindesignandconstruction.Thismeansthatsimilarseismicretrofitshouldsolutionsshouldworkforanumberofbuildings.DBIshoulddevelopstandardplanssetsforseismicretrofitsofcommonandsimplebuildingtypes.Buildingsthataresimilarto
thoseintheplansetcouldusetheseplansforretrofit.PlansetsreducedesigncostsforretrofitsandhavebeeninuseintheEastBayforcripplewallbuildings(abuildingtypethatisnotcommoninSanFrancisco)forseveralyears.
b) Providetrainingforengineersandotherlicensedprofessionalsinconductingbuildingseismic
evaluations.
TheCityshouldofferhands‐ontechnicaltrainingforhowtoconductbuildingseismicevaluations(recommendation3).Thistypeoftrainingwouldhelpmakesurethatevaluationsarecompetent.TheCitycouldpostalistofprofessionalsthathavecompletedthistrainingonitswebsite,which
wouldhelpconsumers.
c) Provideinformationonretrofitcostsandeffectivetechnicalapproachesbasedonexperienceas
theprogramprogresses.TheCityshouldmonitorlessonslearnedwhenownersundertakeretrofits,includingeffectiveretrofitdesign,constructiontechniques,costs,andinnovativeuseoftechnology.TheCitycanshare
theselessonswithbuildingowners,designprofessionalsandcontractorstohelpretrofitprogramsgrowincreasinglyeffectiveandefficientovertime.
d) Providetrainingfordesignprofessionalsandcontractorsinconductingseismicretrofits.TheCityshouldprovidetraininginhowtoconductseismicretrofitting,particularlyinhowtouseupdatedtechnicalstandards.Thistrainingcouldincludeanoverviewofinnovativeproductsand
technologiesdevelopedforseismicretrofits.Again,theCitycouldpostalistofthosewhohavecompletedthistrainingonitswebsite,whichwouldhelpconsumers.
e) Developadditionalstandardsasneededtoreducefallinghazardsandimprovepostearthquakebuildingusability,includingbracingofheavyequipmentandshelves,elevatorfunctionality,etc.
Recommendation11.Providetechnicalassistanceforbuildingretrofits.TheCityshouldhelpresidentsandbuildingprofessionalstoevaluateandseismicallyretrofitbuildingsefficientlyandinaccordancewithCitycodes.
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Safetyandpostearthquakeusabilityareaffectedbytheperformanceofcontents,appliances,equipment,elevatorfunctionality,functionalityofHVACandutilitysystems,andotherbuilding
elementsnotdirectlyassociatedwithabuilding’sstructuralsystem.Theseelementscanposesafetyhazardsduringearthquakes,playabigroleinwhetherbuildingscanbeusedafteranearthquakeandaffectthescopeofeconomiclosses.Thebuildingcodealreadyincludessomestandards.
However,DBIshoulddevelopadditionaltechnicalstandardsforreducingthehazardfromobjectsandsystemsnotcovered.Thesestandardswouldbeusedtoenforceanyrequirementsandguidevoluntaryefforts.
f) Conductinventoriesofstructuraltypesandbuildingusesofconcern.
TherearestructuretypesintheCitythatareknowntoposeriskstothesafetyofresidents,and
buildingusesofspecialimportance.However,theCityhasnoinventoryofexactlywherethesebuildingareorhowmanythereare.DBIshouldleadanefforttogetagoodinventoryofthehighestriskstructuretypesandbuildingswithselectedimportantusesintheCitysoprogramstoaddress
theriskofthesebuildingscanmoveforward.Inventoriesareneededforthefollowingtypesofstructures:
• Concretetiltupbuildings;
• Concreteframebuildingsconstructedpriorto1980;• Concreteandsteelframebuildingswithunreinforcedmasonryinfillwalls;• Earlyretrofittedbuildings;and
• Largeweldedsteelmomentframebuildingsbuiltbefore1994.Listsofownersresponsibleforbuildingswiththefollowingusesareneeded:
• Socialserviceproviders;• Daycarecentersandpreschools;• Medicalserviceproviders;
• Criticalretailservices(e.g.,grocerystores,pharmacies);• Privateschoolsanduniversities;and• Largeinstitutionswithcontrolovermanybuildings.
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Partsofbuildingfaçadescanfalloffandinjurepassers‐byduringearthquakesoratanytime.Manycitieshavepassedlawsrequiringregularinspectionoffaçadesandotherbuildingelementsthatcouldfall,andrequiringmaintenanceofdeficientconditions.SanFranciscoshouldhavesuchanordinance.San
Franciscoenactedmeasuresinthe1970’stobraceparapetsandtopreventexteriorbuildingelementsfromfallingonthesidewalksoradjacentbuildings.Thesemeasuresshouldbeextendedtoaddressbuildingfaçadesandcladdingvulnerabletofalling.
Recommendation12.Enactafaçadeordinance,requiringperiodicinspectionoffaçades,parapetsanddecorativefeaturesfixedtobuildingexteriors,andrequirerepairofmaterials
foundtobefallinghazards.
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Largeearthquakesnearabigcityarerare.Scientistsandengineerslearntremendousamountabouthowtobuildearthquake‐resilientcommunitiesfromeachsuchevent.TheCityshouldengagewithongoingreviewofstructural,geotechnicalandsocialsciencetopicstomakesureissuesimportanttoSan
FranciscoareaddressedandappliedinSanFrancisco.AsevidencethattheCitycaninfluenceresearch,theCAPSSproject’sworkonwoodframesoft‐storybuildingshasalreadyresultedinthetechnicalcommunityworkingtodefinebetterstandardsforretrofitsofthistypeofstructure.
ThefollowingactivitieswouldprovideinformationhelpfultoSanFrancisco:
a) Plandatacollectionprogramstofollowthenextdamagingearthquake,focusedonlearningaboutissuesofpolicyimportancetoSanFrancisco.
TheCityshouldplannowtomakesurethatimportantlessonsrelevanttoSanFranciscoarelearnedfromthenextearthquaketostriketheCity.Earthquakedamageisephemeral,disappearingasresidentsrepairandrebuild.Datacollectionprogramsshouldbeplannedinadvance.Thiswillhelp
theCitybebetterpreparedfortheinevitableearthquakesthatfollow.
b) Supporteffortstotestandresearchinnovativeandlow‐costretrofitconcepts,suchasbracing
garagedoorsandaddingductilityandenergyabsorptiontobrittleorweakbuildingelements.DBIshouldworkwithuniversities,companiesandindividualsdevelopinginnovativeandpotentiallylow‐costsolutionsforseismicretrofits.Encouragingsuchinnovatorstoconductdemonstration
projectsortoconductseminarsinSanFranciscocanhelpmovethesetechnologiesclosertorealityandchannelthemindirectionsthatmakesenseforSanFrancisco.
c) Supportresearchneededtomodernizeandimproveevaluationandretrofitstandards.Currentbuildingcodesgenerallyrelyonanalysismethodsthataredecadesold.Moremodernmethods,suchasthosedevelopedforPerformanceBasedDesign,areincreasinglybecomingviable
approachesforretrofitsandbuildingcodes.DBIshouldworkwiththeresearchcommunitytohelptranslateimprovedanalysismethodsintopracticalcodestandardsthatcouldbeadoptedbytheCity.
d) Reexaminetheexpectedperformanceofpreviouslyretrofittedbuildings.
SanFranciscopioneeredeffortstoimprovetheearthquakeperformanceofitsbuildingstock.Inthe
1970’stheCityrequiredbuildingownersbraceparapetsanddecorativeelementsandbeganrequiringretrofittingofvulnerablebuildingsbeforetheywereenlargedorrenovatedtochangetheir
Recommendation13.Promotedevelopmentandimplementationofeffectiveideasonearthquakeriskreduction.TheCityshouldencourageeffortstoimproveknowledgeabout
buildingperformanceandeffectivewaystoreduceearthquakeriskthatarerelevanttoSanFrancisco.
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use.Inthe1990’stheCitybeganitsprogramtoretrofitunreinforcedmasonrybuildings,exceptforresidentialbuildingswithfourorfewerunits.Sincethen,knowledgeaboutretrofittinghaschanged
insignificantwaysandsomeoftheearlyretrofitsmightnotprovidetheperformancetheownersandtenantsexpect,orthattheCityrequires.TheCityshouldconductacarefulanalysisofpreviousretrofits,especiallytheuseofthin‐wallsteeltubebracedframes.TheCityshouldreportwhether
additionalretrofitsareneededtoprotectpublicsafetyandimprovetheCity’sresilience.
e) StudythehazardfrommasonrychimneysinSanFrancisco,andrecommendnecessarymitigation
measures.Masonrychimneys,mostlyonsmalldwellings,oftenareunreinforcedandpronetofallingdangerously.SanFrancisco’sfirechiefwaskilledwhenachimneyfellduringthe1906earthquake.
Unreinforcedchimneysarenotallowedbycodeandsomecitiesencouragetheirremoval.TheextentofrisktoSanFranciscansneedsfurtheranalysis.
f) Supportinstallationofinstrumentstomeasurebuildingmovementinearthquakes.
Recordsofbuildingmovementsduringearthquakesprovideinformationthatisusefulwhenevaluatingtheextentofdamageabuildinghasexperiencedanditslevelofpost‐earthquakesafety.Therecordingsalsoprovideevidencetobetterunderstandhowbuildingsrespondwhensubjected
tostrongshaking.
g) Studythefeasibilityofadministrativemeasurestomitigateagainstgroundfailuresthataffectmultiplepropertiesandcannotbecompletedbyasinglebuildingowner.Liquefactionandlandslidegroundfailuresgenerallyinvolvemorethanasingleparcel,makingit
difficultforasingleownertoaddressthehazard.Administrativearrangements,suchasopt‐indistricts(geologichazardabatementdistricts)canbeusedtofundandexecuteprojectsinvolvingseveralowners,governmentagenciesandutilities.Administrativemeasureswillbeneededwhen
remediationtechnology(below)advancestobecomeuseful.
h) Periodicallyreviewliquefactionremediationtechnologyandprovideguidancetoownersinpotentialliquefactionzoneswhentechniquesbecomefeasible.Currentresearchintoliquefactionremediationmeasuressuitableforbuiltupareasshowssome
promise,butitnotyetreadyforwidespreadcommercialapplication.TheCityshouldmonitorprogressperiodicallyandconsideradministrativewaystousethetechnologywhenappropriate.
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FirestriggeredbyearthquakesposeaseriousriskthattranscendsCitydepartments.Strongeffortsareneededtoreducethenumberofignitionsthatoccurafterfutureearthquakesandlimittheabilityoffiresthatdooccurtospreadtoadjacentbuildings.Issuesthataffectignitions,firespread,andfire
suppressionaretheresponsibilityofanumberofCitydepartments,privateowners,andentitiesoutsideofCitycontrol(e.g.,PacificGasandElectriccompanyandpropertyinsurers).Themostsensiblewaystomanagepost‐earthquakefireriskshouldbedeterminedthroughdialogueofallofthesegroups.Eachof
thesegroupsshouldsharewhattheyknowwithothergroups,tohelpeveryonemakegooddecisionsforSanFrancisco.
AdiversegroupofCityDepartmentsandothersshouldevaluateandconsiderimplementingthe
followingactions:
a) ImprovewatersupplysystemstocoverthoseneighborhoodsnotservedbytheAuxiliaryWaterSupplySystem.
TheAuxiliaryWaterSupplySystemprovidesaredundantwatersystemforfightingfiresafterearthquakes,andatothertimes,andincorporatesmanyearthquakeresistantfeaturesinitsdesign.However,thissystemcoversonlythenorthernandeasternCityneighborhoods,thosethatwere
developedintheearlypartoflastcenturywhenthesystemwasconstructed.TheCityneedsadequate,reliablewatersourcestofightfirepost‐earthquakefiresinallneighborhoods.ThereareanumberofoptionstoimprovethewatersupplyinneighborhoodsnotservedbytheAuxiliary
System,includingexpandingtheCity’sPortableWaterSupplySystem,whichcanbedeployedwhereverneeded.Thisimportantissueneedstobeaddressedassoonaspossible.
b) ExpandthetrainingandscopeofNeighborhoodEmergencyResponseTeams(NERT)toincludefiresuppression,firereporting,assistingvulnerableresidents,andassistingwithneighborhood
recovery.TheSanFranciscoFireDepartmentrunstrainingprogramsforNeighborhoodEmergencyResponseTeams(NERT)andhastrainedthousandsofresidentstohelptheirneighborhoodsafteran
emergency.NERTvolunteerscouldbetrainedtohelpinnewways,includingbasicfiresuppression,firereporting,andhelpingneighborswhoaredependentonfunctioningutilitiesandothersforthedeliveryoffood,water,oxygen,medicineandhealthservices.TheCityshouldexaminehowtotake
maximumadvantageoftheenthusiasmofNERTteamstohelptheCitytorespondtoandrecoverfrommajorearthquakes.
Recommendation14.Evaluatemeasurestoreducepost‐earthquakefires.MultipleCityDepartmentsshouldworktogethertoevaluateandimplementmeasurestoreducefire
ignitionsandspread,andimprovefiresuppressioncapacityfollowingearthquakes.
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c) Increaseaccessibilityofwatershutoffvalvesonbuildingfiresprinklersystemstocontrolwaterlossfromdamagedsprinklersystems.
Damagedwatersprinklersystemsbrokenbyearthquakeshakingcanleak,contributingtolossofwaterneededtofightfiresfromthemunicipalwatersystem.TheCityshouldinvestigatewhethermakingshutoffvalvesforthesesystemsmoreaccessibleisacosteffectivewaytoimprovepost‐
earthquakewateravailability.
d) Improvestorageofchemicalsineducationalscienceandotherlabs.
Inpastearthquakes,anumberofignitionshavestartedinchemistrylabs.Theseignitionscouldbereducedthroughproperstorageofchemicals.TheCityshouldinvestigatehowthatcouldbeaccomplished.ManyoftheeducationalfacilitieswithchemistrylabsdonotfallunderCity
jurisdiction(e.g.,publicschoolsanduniversities),buttheriskofignitionsinthesebuildingsspreadingfiretoneighboringbuildingsmeansthatitmakesensefortheCitytoworkwithrelevantgroupstoaddressthisissue.
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Fallinghazards,suchasfurnituretopplingorceilingfixturesfalling,causeseriousproblemsinevery
earthquake,includingdeaths,increasedeconomiclosses,andmakingbuildingspaceunusable.DBIshouldinitiateacomprehensiveprogramtoencourage,andinsomeinstances,requiremeasurestoreducethesehazards.Buildingcommunications,electrical,plumbingandHVACsystems,elements
suchasstairsandelevators,furnishings,appliancesandequipment,andinventoriescanbemorevaluablethanthebuildingstructures.Theseelementsgreatlyaffectwhetherbuildingscanbeusedfollowingearthquakes,themagnitudeoflossesandsafetyofinhabitants.Measurestoreduce
damagetotheseelementsgenerallyarenotdifficultandareaffordable.Thecomprehensiveapproachrecommendedwouldbecarriedoutaspartofthethree‐stepstrategythroughstep1publicinformation,step2evaluationsandstep3retrofits.
Recommendation15.Initiateacomprehensiveprogramtoaddressthehazardsfromdamagetofurnishings,appliancesandequipmentandnon‐structuralbuildingelements.
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Theprecedingfifteenrecommendationsinthisreportcallforsignificantnewpoliciesandprogramsto
improvetheearthquakeresilienceofSanFrancisco’sbuildingstock.DBIshouldcommissionanindependentevaluationatleasteveryfiveyearstoreviewprogressandconsequencesoftheresultingprogramandtomakerecommendationsforimprovingit.Therecommendationsinthisreportare
interrelated,andwillbemosteffectiveifimplementedasacompleteprogram,insteadofpiecebypiece.TheevaluationshouldlookatwhatactionshavebeentakenbytheCityandhighlightimportantstepsthatmayhavebeenneglected.Theevaluationshouldalsorecommendadjustmentsbasedon
lessonslearned.Althoughtheserecommendationshavebeencarefullyselected,someofthemmaynotworkasintendedwhenimplemented.ItisimperativethattheybereviewedperiodicallytomeasuretheireffectivenessinreachingtheCity’sobjectivesandtorecommendchangestomakethemwork
better.
Recommendation16.Periodicallyevaluateprogressandimplementationoftheserecommendations.
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Building Categories and Deadlines
Categories of Buildings
TheCityshoulddividethebuildingstockinto“categories,”orgroupsofbuildingsdefinedbytheimportanceofabuilding’suseoroccupancy,itstypeofstructuralsystem,orboth.Thiswayofgrouping
buildingsallowssettingprioritiesbasedonboththeimportanceofbuildingstothecommunityandpublicsafety.Allbuildingsinacategorywouldbemovedthroughthethree‐stepapproach—information,evaluation,andretrofit—asappropriate.Thesequenceinwhichbuildingcategorieswould
beaddressedwouldbeassignedbasedonhowimportantthetypeofbuildingistoSanFrancisco’sresilience(e.g.,twoimportantusesarerentalhousingandprivateschools)orthethreatthebuildingtypeposesforinjuriesanddeaths(e.g.,structuralcategorieswithknownsafetyrisksinclude
unreinforcedmasonrybearingwallbuildings,concretetilt‐upbuildings,andconcreteframebuildingsconstructedbefore1980).
Manybuildingswouldbeincludedintwocategories,onebecauseoftheiruseandanotherbecauseof
thetypeofstructure.Thecategoryapproachedfirstwouldtakeprecedence,buttheretrofitstandardsshouldbethesame.Forexample,ifthereisanassistedlivingfacilitylocatedinalargeconcretebuildingconstructedbefore1980,theownerwouldberequiredtoevaluatethebuildingbecauseithousesan
assistedlivingfacility,notbecauseitisanolderconcretebuilding.Whentheprogramadvancestothecategoryofolderconcretebuildings,buildingsevaluatedandretrofittedearlierwouldbeexempt.
TheCitycouldchoosetoprioritizewithineachcategorysothatbuildingswithgreaternumbersof
occupants,moreimportantuses,locatedonweaksoils,orwithgreatervulnerability,oracombinationoftheseattributes,wouldbeaddressedfirst.Thesecharacteristicscouldbeidentifiedwhenaninventoryofbuildingsinthecategoryisprepared.
Thisreportrecommends19categoriesofbuildings,basedonuse,structuretypeorboth.Eachcategoryisdescribedbelow.Table4‐3summarizesthecategoriesandhowtheyarecomprisedofbothusesandbuildingtypes.
• WoodframeresidentialbuildingswiththreeormorestoriesandfiveormoreunitsThereareabout4,400buildingsofthistype,manywithasoft‐storyconditionatthegroundlevel.Asoft‐storyissignificantlyweakerormoreflexiblethanthestoriesaboveit.Theweakness
atthegroundlevelusuallycomesfromlargeopeningsinperimeterwalls,duetogaragedoorsorstorewindows,and/orfewinteriorpartitionwalls.Duringstrongearthquakeshaking,thegroundlevelwallscannotsupportthestiffandheavymassofthestoriesabovethemasthey
movebackandforth.Thegroundlevelwallscouldshiftsidewaysuntilthebuildingcollapses,crushingthegroundfloor.Thisbuildingtypeisexpectedtoberesponsibleforaboutone‐thirdofhousingunitsthatcannotbeoccupiedafterfutureearthquakes.Retrofitsofthistypeof
structurearerelativelyeasyandinexpensive,comparedtootherstructuretypes.TheriskofthistypeofbuildingandthebenefitsassociatedwithretrofitsareexploredindetailintheCAPSSreportEarthquake Safety for Soft‐Story Buildings (ATC52‐3).TheMayorformedataskforceto
createaprogramandlegislationtoimplementthereport’srecommendations.
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• Residentialbuildingswiththreeandfourunits
Thereareanestimated6,000woodframeresidentialbuildingswiththreetofourunits.Manyofthesehaveasoft‐storyatthegroundlevel.Therealsoareasmallnumberofunreinforcedmasonrybuildingsthatwereexemptfromtheearliermandatoryretrofitprogram,anda
numberofbuildingsofvariousotherstructuraltypes.Thesebuildingsareexpectedtoberesponsibleforaboutone‐thirdofresidentialunitsthatcannotbeoccupiedafteralargeearthquake(inadditiontothethirdassociatedwithlargerwoodframebuildings,discussed
above).AmandatoryprogramaddressingthesebuildingsshouldbeginassoonasprogressonthefiveunitbuildingsprogressestothepointthatDBIcanexpandtheprogram,aboutfiveyearsfromthepresent.
• Concreteresidentialbuildingsbuiltbefore1980
Olderreinforcedconcretebuildingscanexperienceextensivedamageanddramaticanddeadly
collapsesduringearthquakes.Suchcollapsesareresponsibleformanyofthecasualtiesinearthquakesaroundtheworld.ThereareolderreinforcedconcretebuildingsinSanFranciscobeingusedasapartmentbuildingsandresidentialhotels.Thousandsofpeopleliveinthese
buildingsandmanywouldbedisplacedbydamage.PersonsresidinginSROsandtransienthotelswouldbehardhitbecausereplacementbuildingswouldtakeyearstoconstruct.Retrofitofthesebuildingsmaybeexpensive,butisimportantduetotheriskstheyposetotheCity.It
maymakesensetoretrofitthesebuildingstoa“collapseprevention”standard,recognizingthat,evenafterretrofit,manyofthemmaynotbehabitableorrepairableafteranearthquake.
• Othertypesofresidentialbuildingswithfiveormoreunits
Thiscategoryincludesalllargeresidentialbuildingsnotconstructedfromwoodorconcretethat
arefoundtobevulnerablethroughevaluation.Thiscategoryincludesdiverseandvulnerablebuildings,suchasreinforcedmasonryandsteelframebuildingswithmasonryinfillwalls.Mostly,thesebuildingsaremulti‐unit;manyofthemhavehistoricfeatures.Manyofthese
buildingsprovidehousingforlowincometenantsandwillbedifficulttoreplace.Itmaybeappropriatetoretrofitsomeofthesebuildingstoa“collapseprevention”standard.
• SinglefamilyhomesandtwounitresidencesThisisbyfarthemostcommontypeofbuildinginSanFrancisco,withanestimated112,000single‐familyhomesandalmost20,000two‐unitresidentialbuildings.Manyofthesebuildings
arevulnerabletoearthquakesbecauseofgaragesatthegroundlevelcreatingaweakorsoft‐storycondition.Thereareasmallnumberofunreinforcedmasonrybuildingsofthissizethatwereexemptedfromtheearliermandatoryprogram.DBIshoulddevelopprescriptivestandards
fortypicalbuildingsthatwouldimprovethelikelihoodthatresidentscouldshelterinplace.
• Non‐profitsprovidingimportantservicestovulnerablepopulations
Theseprovidersservethehomeless,personsconfinedtotheirhomesduetohealthordisabilities,personswithmedicalorpsychologicalissues,thepoorandothers.ManyCity
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agenciesusetheseorganizationstodeliverservices.TensofthousandsofSanFranciscansrelyontheseorganizationsforservicesthatkeepthemalive.
• PreschoolsanddaycarecentersChildreninpreschoolanddaycarecentersshouldbesafeinearthquakes,justastheiroldersiblingsareinpublicschools.Moreover,parentsrelyonthesefacilitiestocarefortheirchildren
whiletheywork.SanFrancisco’srecoveryfollowingearthquakesdependsonpeoplereturningtowork.
• Clinicsandfacilitiesprovidingurgentandcriticalmedicalservices
Neighborhoodurgentcareandpsychologicalclinics,dialysiscenters,medicalsuppliers,andhospitalfacilitiesnotregulatedbytheStateofCalifornia9providecriticalservicestoSanFranciscans.Theseserviceswouldbeneededtotreatthethousandsofinjuriesthatdonot
requirehospitalizationimmediatelyafterearthquakes,andinthedays,weeksandmonthsthatfollow.
• PrivateK‐12schoolsandprivateuniversities
Mostpeopleassumethatschoolbuildingsaresafe,butprivateschoolsareprobablynosaferthanthegeneralbuildingstock.ManyofSanFrancisco'sprivateschoolbuildingswereconstructedwhenbuildingstandardsweremuchlessstringentthantoday.Nearlyonethirdof
schoolchildren—morethan23,000—attendprivateschoolsinSanFrancisco,thehighestrateintheentirestate10.TheCitymustensurethatallofSanFrancisco’schildrenattendschoolinbuildingsthatmeetstandardsequivalenttothestandardsforpublicschools.TheCAPSSproject
didnotconsiderpublicschools,whichserveabout55,000studentsinSanFrancisco.PublicschoolsbuilttostatestandardsareamongthemostearthquakeresistantbuildingsinCalifornia.
However,likeotherbuildings,somewereconstructedtoolderstandardsandsomeofthebuildingsconstructedbeforethestatestandardswereadoptedin1933wereretrofitted,butdonotprovidefortheperformanceexpectedfrommodernschoolbuildings.In2002,the
DepartmentofConservation,DivisionoftheStateArchitectpublishedalistofpublicschoolbuildings,Seismic Safety Inventory of California Public Schools,toidentifynonwoodframeschoolbuildingsbuiltbeforeJuly1,1978thatshouldbeevaluatedbecauseoftheirageand
buildingtype.Thereare72buildingsbelongingtotheSanFranciscoUnifiedSchoolDistrictonthislist.
• AssistedLivingfacilitiesTheCity’selderlyanddisabledshouldbeinfacilitiesthataresafeandfunctionalafterfutureearthquakes.Relocationafteranearthquakewouldbehardestontheseresidents.TheCity
wouldneedtoprovideassistancetonon‐profitfacilitiesandthoseservinglow‐incomeresidents.
• Concretenon‐residentialbuildingsbuiltbefore1980
9StatelawgivestheOfficeofStatewideHealthPlanningandDevelopmentauthorityoverthedesignandconstructionofacutecarehospitalandskillednursingfacilities.10CaliforniaDepartmentofEducation,2009.
WorkingDraftCAPSSTask4Report page57
Olderreinforcedconcretebuildingscanexperiencedramaticanddeadlycollapsesduringearthquakes.Suchcollapsesareresponsibleformanyofthecasualtiesinearthquakesaround
theworld.ThereareolderreinforcedconcretebuildingsinSanFranciscobeingusedasofficebuildingsandwarehouses.Thousandsofpeopleusethesebuildingsdaily.Retrofitofthesebuildingsmaybeexpensive,butisimportantduetotheriskstheyposetotheCity.Itmaymake
sensetoretrofitthesebuildingstoa“collapseprevention”standard,recognizingthat,evenafterretrofit,manyofthemmaynotberepairableafteranearthquake.
• HotelsandmotelsservingtouristsHotelsandmotelsofallstructuraltypesmustbesafeduringandquicklyreoccupiedafterfutureearthquakes.Hotelsplayakeyroleduringpostearthquakerecoverybyhousingemergency
workers,includingthosebroughttotheCitytorestoreutilities.Moreover,becausetourismisakeypartoftheCity’seconomy,improvingtheperformanceofvisitorservingbuildingsiscriticalfortheCity’searthquakerecovery.
• Criticalretailstoresandsuppliers
CertainbusinessesarecriticaltohelpingtheCityrecoverquicklyanditisdesirabletohavethem
operationalassoonaspossible.SanFranciscansneedpharmacies,grocerystores,andsimilarretailestablishmentsthatprovidetheitemsrequiredfordailyliving.Someoftheseimportantbusinessesmaybelocatedinweakbuildingsthatwouldnotbeusableafteralargeearthquake.
Manyofthesebusinessesmayrentthespacetheyuse,andretrofittimelinesshouldallowtimetorenegotiateleasesaspartofthisprocess.
• Buildingsusedbylargeaudiences
Theaters,placesofworshipandotherbuildingsthatareusedtogathermanypeopleneedtobe
safe,consideringbothdamagetothebuildingandfallinghazards.Althoughmanyofthesebuildingsareoccupiedonlyafewhourseachweek,whentheyareoccupiedthereisthechanceofalargenumberofcasualties.
• Historicbuildings,andcontributingbuildingsinhistoricdistricts
HistoricresourcebuildingsshouldberepairableafterfutureearthquakessotheCitymaintainsit
heritage.Thiscouldincludemanyoldermasonrybuildingspreviouslyupgradedtostandardsonlyintendedtoreducecasualties,butnottoassurereparability.
• Concretetilt‐upbuildingsThesebuildingshaveheavyprecastconcretepanelsthatareraisedinplacetoformthebuildingwalls.Ifthewallsarenotadequatelyconnectedtoeachotherandtotheroof,theycanseparate
whenshakenbyanearthquake,causingtheroofandwallsectionstocollapseontheoccupantsandcontentsofthebuilding.Thisstructuretypeisoftenusedforindustrialpurposes,butmayalsobeusedforsomegrocerystoresorothercommercialpurposes.Thereareanestimated200
oftheseinSanFrancisco.Thesebuildingsarerelativelyeasyandinexpensivetoretrofit,comparedtootherstructuretypes,andanumberofcommunitieshaveenactedretrofit
WorkingDraftCAPSSTask4Report page58
programsforthistypeofbuilding.PrescriptivestandardsforretrofittingareavailableforadoptionintotheSanFranciscoBuildingCode.
• Largeworkplaceswithweldedsteelmomentframesbuiltbefore1994.
Manyofficebuildingsandworkplaceswereconstructedwithweldedsteelmomentframeswith
detailsthatwerefoundvulnerableintheNorthridgeearthquake.Weldingproceduresandconnectiondetailswerechangedin1994toimprovetheperformanceofbuildingsbuiltsincethen.Theconnectiondetailsusedbeforethencanbedamaged,resultinginbuildingsthat
cannotbeusedandmighthavetoberazed.Theselargebuildingsshouldberetrofittedtoreducethechanceofdamageandincreasethelikelihoodthatthebusinessestheysupportwillnotbedisplacedandthebuildingscanberepairedandreoccupiedquickly.
• Earlyretrofittedbuildings
Someretrofitsconducteddecadesagomaybeinadequate.Theseincludeearlyretrofitswith
thin‐wallsteeltubebracedframes,thosemeetingverylowstandards,andthosewithpartialretrofitsnotmeetinganadoptedstandard.Intheseearlyretrofits,tubewallsmaybetoothin,allowingbucklingtooccur,weldedconnectionsmightbeinadequate,ortheremaybeother
vulnerabilities.• Otherbuildingscategories
Thereareothercategoriesofvulnerablebuildingsandimportantbuildingusesnotincludeon
thislist.Buildingswithmixedstructuralsystemsandparkingstructuresareexamples.TheCityshouldaddadditionalcategoriesastheneedarisesaspartoftheregularevaluationof
mitigationprograms(recommendation16).
Table4‐3.BuildingCategoriesSummary
BuildingCategory EstimatedNumberofBuildings
CategoriesBasedonlyonStructuralSystemsConcretetilt‐upbuildings 200
Earlyretrofittedbuildings Unknown
CategoriesBasedonStructuralSystemandUseWoodframeresidentialbuildingswiththreeormorestoriesandfiveormoreunits
4,400
Concreteresidentialbuildingsbuiltbefore1980 Unknown
Othertypesofresidentialbuildingswithfiveormoreunits Unknown
Concretenon‐residentialbuildingsbuiltbefore1980 Unknown
Largeworkplaceswithweldedsteelmomentframesbuiltbefore1994 Unknown
WorkingDraftCAPSSTask4Report page59
CategoriesBasedOnlyonBuildingUseResidentialbuildingswiththreeandfourunits Morethan6,000
Single‐familyhomesandtwo‐unitresidences 112,000singlefamily20,000twounit
Non‐profitsprovidingimportantservicestovulnerablepopulations Unknown
Preschoolsanddaycarecenters Unknown
Clinicsandfacilitiesprovidingurgentandcriticalmedicalservices Unknown
PrivateK‐12schoolsandprivateuniversities About100privateK‐
12schools,xxcollegesanduniversities
AssistedLivingfacilities Unknown
Hotelsandmotelsservingtourists Unknown
Criticalretailstoresandsuppliers About30large
grocerystoresand100pharmacies
Buildingsusedbylargeaudiencesincludingplacesofworship Unknown
Historicbuildings,andcontributingbuildingsinhistoricdistricts Unknown
Sources:Potential Earthquake Impacts(ATC52‐1,2010).
Recommended retrofit deadlines for building categories ThisreportrecommendsthatSanFrancisco’sbuildingsgothroughathree‐stepprocesstoimprovetheirseismicresilience—information,evaluation,andretrofit.Thefirststep,providinginformationandincentivestoinformandassistowners,shouldbeginimmediatelyforallbuildingtypes
(recommendations1,2,8,10and11).Thesecondstep(recommendation3),requiringevaluationuponsale,shouldbeginforallbuildingtypeswithinfiveyears.Thefive‐yeartimeframeallowstheCitytimetoadoptevaluationcriteriaandproceduresandimprovedretrofitstandardsbeforethemandatory
evaluationscommence.
Thethirdandfinalstep,mandatoryretrofits,shouldbeginimmediatelyforsomebuildingcategories,andshouldconcludeforallbuildingcategoriesinthirtyyears.ThisreportrecommendstheCityenactmandatoryretrofitrequirementsforthefollowingbuildingcategoriesinthefollowingtimeframe:
Ongoing
WorkingDraftCAPSSTask4Report page60
• Continuetoenforceretrofittingbuildingsaspartofsignificantrepairs,alterations,expansions,changesofuse,andrepairofdamageabovespecifiedthresholds.Retrofittingshouldbe
requiredasaconditiontoconvertingmulti‐unitresidentialbuildingstocondominiums.
Begintorequireretrofittingimmediatelyandaccomplishwithintenyears
• Woodframeresidentialbuildingswiththreeormorestoriesandfiveormoreunits• Concretetilt‐upbuildings
Begintorequireretrofittinginfiveyearsandcompletewithinfifteenyears
• Residentialbuildingswiththreeandfourunits• PrivateK‐12schoolsandprivateuniversities
• AssistedLivingfacilities
Startintenyearsandcompletewithintwentyyears
• Concreteresidentialbuildingsbuiltbefore1980• Othertypesofresidentialbuildingswithfiveormoreunits• Hotelsandmotelsservingtourists
• Criticalretailstoresandsuppliers
Startwithintwentyyearsandcompletewithinthirtyyears
• Singlefamilyhomesandtwounitresidences• Concretenon‐residentialbuildingsbuiltbefore1980
• Buildingsusedbylargeaudiences• Historicbuildings,andcontributingbuildingsinhistoricdistricts• Largeworkplaceswithweldedsteelmomentframesbuiltbefore1994.
• Earlyretrofittedbuildings
Other Categories Thefollowinguse‐basedbuildingcategoriesareveryimportanttoSanFrancisco’searthquakeresilience.
However,manyoftheseorganizationsarenotprofitentitiesthatdonotownthebuildingstheyoccupy.ThisreportrecommendsthattheCityassistthesegroupstoevaluateandretrofitbuildingswherepossible,orrelocate,ifnecessary.However,buildingsusedforthesepurposeswouldtriggermandatory
retrofitiftheyalsofallunderoneoftheothercategories,suchasaconcretebuildingbuiltbefore1980.
Othercategories:
• Non‐profitsprovidingimportantservicestovulnerablepopulations• Preschoolsanddaycarecenters• Clinicsandfacilitiesprovidingurgentandcriticalmedicalservices
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