Here Today—Here Tomorrow: The Road to Earthquake Resilience in San Francisco · 2020-01-04 · 2....

WorkingDraftCAPSSTask4Report page1

DRAFTCAPSSTASKFOURREPORT

HereToday—HereTomorrow:

TheRoadtoEarthquakeResilienceinSanFrancisco

ACommunityActionPlanforSeismicSafety

Draftdate:December3,2010


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.


• 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.


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


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


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.


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.


• 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%


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.


1&2familywoodframesoJ‐storyresidences;22%

3&4unitwoodframesoJ‐storyresidences;34%

5&moreunitwoodframeresidenceswith3ormorestories;33%

Concretebuildingsbuiltbefore1980;

6%

Allothertypesofbuildings;5%


• 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.


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


• 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.


• 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


businessesandjobmarket,thiscoulddrivedemographicchangesthatreduceSanFrancisco’ssocioeconomicdiversity.


• 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.


• Limitingdamagetoprivatelyownedbuildingsandtheensuingfinancialimpactswouldimprovepost‐earthquakegovernmentrevenuesfromproperty,salesandhoteltaxes.

Conclusion

TheanalysisoffourpossibleearthquakestostriketheCitymakesitclearthat,asitistoday,theCityshouldexpectalotofdamagefromfutureearthquakes.Asdescribedabove,widerangingconsequenceswillflowfromthatdamage,causingrecoverychallengesforallresidents,especiallybuildingowners.San

Franciscowillrecover,butitwillbeforeverchangedbyloosingworkersandbusinessesthatrelocateratherthanforrecovery.Takingstepstomitigateearthquakedamagebeforethenextearthquakestrikescanavoidmanyoftheseconsequences.Inthefollowingchapters,thisreportrecommendsa

comprehensiveprogramfortheCitytoimproveitsearthquakeresiliency.


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.


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


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;


• 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


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


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


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.


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.


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


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.


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


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


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


X X X X X

Mitigationobjectives:

a) Residentswillbeabletostayintheirownhomesb) Residentswillquicklyhaveaccesstoimportantprivately‐runcommunityservicesc) Nobuildingwillcollapsecatastrophicallyd) Businessesandtheeconomywillquicklyreturntofunctionalitye) TheCity’ssense of placewillbepreserved


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


X


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.


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.


h) TrainpreservationengineersandarchitectsknowledgeableaboutSanFrancisco’shistoric

resourcesinpost‐earthquakesafetytagging.SanFrancisco’sbuildingstockisuniqueandbeautiful.Toensurethatitstaysthatway,theCityshouldmakesurethatengineersandarchitectsthatareknowledgeableaboutpreservationissues

areinvolvedinpost‐earthquakebuildingsafetyevaluationsandtagging.Thetaggingprocessoccursimmediatelyafteranearthquakeandinfluencesrepairanddemolitiondecisions.Historicresourceissuesmustbeconsideredinthesedecisions.TheCityshouldconductoutreachtothepreservation

communitytomakesurethattheyaretrainedtoassistinthisprocess.


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.


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.


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.


• 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.


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.


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.


Churches,temples,mosquesandotherreligiousbuildingshavelargeoccupanciesduringservices.Theyalsoprovidecriticalservicestothebroadercommunity.Thesebuildingsoften

haveearthquakevulnerabilitiesduetotheirsize,configuration,ageandfallinghazards.Duringearthquakestheyposeseriousthreatstothesafetyofoccupants,andtheresultingdamagewouldlimittheirabilitytoprovideservicestothecommunity.


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.


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.


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.


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.


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.


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.


DBIisintheprocessofinstallinganupdateddatabasesystem.Thissystemshouldincludearangeof

informationtosupportearthquakeriskreductionprograms,suchasthefollowing:

• Informationaboutbuildinguse• Whetherandwhenbuildingshaveundergoneseismicretrofits,andtowhatstandardabuilding

wasretrofitted• Buildingstructuraltypeandcharacteristicsthataffectvulnerability• Thefindingsofbuildingseismicevaluations

DBI’scurrentdatabasesystemdoesnotincludeinformationaboutseismicretrofitsorvulnerabilityandcannotaggregateandmanipulateinformationforevaluationandtrackingcitywideprogressofmitigationprograms.

Recommendation10.Trackevaluationsandretrofitsinadatabasesystem.TheCityshouldincludeinformationrelatingtoseismicevaluationsandretrofitsinDBI’supdateddatabasesystemtoallowtrackingprogressofmitigationactivitiesandrecordinginventories,evaluation

reportsandretrofitinformation.


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.


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.


Partsofbuildingfaçadescanfalloffandinjurepassers‐byduringearthquakesoratanytime.Manycitieshavepassedlawsrequiringregularinspectionoffaçadesandotherbuildingelementsthatcouldfall,andrequiringmaintenanceofdeficientconditions.SanFranciscoshouldhavesuchanordinance.San

Franciscoenactedmeasuresinthe1970’stobraceparapetsandtopreventexteriorbuildingelementsfromfallingonthesidewalksoradjacentbuildings.Thesemeasuresshouldbeextendedtoaddressbuildingfaçadesandcladdingvulnerabletofalling.

Recommendation12.Enactafaçadeordinance,requiringperiodicinspectionoffaçades,parapetsanddecorativefeaturesfixedtobuildingexteriors,andrequirerepairofmaterials

foundtobefallinghazards.


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.


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.


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.


c) Increaseaccessibilityofwatershutoffvalvesonbuildingfiresprinklersystemstocontrolwaterlossfromdamagedsprinklersystems.

Damagedwatersprinklersystemsbrokenbyearthquakeshakingcanleak,contributingtolossofwaterneededtofightfiresfromthemunicipalwatersystem.TheCityshouldinvestigatewhethermakingshutoffvalvesforthesesystemsmoreaccessibleisacosteffectivewaytoimprovepost‐

earthquakewateravailability.

d) Improvestorageofchemicalsineducationalscienceandotherlabs.

Inpastearthquakes,anumberofignitionshavestartedinchemistrylabs.Theseignitionscouldbereducedthroughproperstorageofchemicals.TheCityshouldinvestigatehowthatcouldbeaccomplished.ManyoftheeducationalfacilitieswithchemistrylabsdonotfallunderCity

jurisdiction(e.g.,publicschoolsanduniversities),buttheriskofignitionsinthesebuildingsspreadingfiretoneighboringbuildingsmeansthatitmakesensefortheCitytoworkwithrelevantgroupstoaddressthisissue.


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.


Theprecedingfifteenrecommendationsinthisreportcallforsignificantnewpoliciesandprogramsto

improvetheearthquakeresilienceofSanFrancisco’sbuildingstock.DBIshouldcommissionanindependentevaluationatleasteveryfiveyearstoreviewprogressandconsequencesoftheresultingprogramandtomakerecommendationsforimprovingit.Therecommendationsinthisreportare

interrelated,andwillbemosteffectiveifimplementedasacompleteprogram,insteadofpiecebypiece.TheevaluationshouldlookatwhatactionshavebeentakenbytheCityandhighlightimportantstepsthatmayhavebeenneglected.Theevaluationshouldalsorecommendadjustmentsbasedon

lessonslearned.Althoughtheserecommendationshavebeencarefullyselected,someofthemmaynotworkasintendedwhenimplemented.ItisimperativethattheybereviewedperiodicallytomeasuretheireffectivenessinreachingtheCity’sobjectivesandtorecommendchangestomakethemwork

better.

Recommendation16.Periodicallyevaluateprogressandimplementationoftheserecommendations.


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.


• 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


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.


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


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


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


• 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

Here Today—Here Tomorrow: The Road to Earthquake Resilience in San Francisco · 2020-01-04 · 2....

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