REDUCING NATURAL HAZARD RISK AND INCREASING RESLIENCE

Mary Lou ZobackConsulting Prof., Geophysics

1SEISMIC HAZARDS AND THE BUILT ENVIRONMENT-Cascadia Hazards Institute, Central WA Univ., April 4, 2014

Natural Hazard Assessment

1. Size, location, and likelihood of future events

Bay Area Earthquake Likelihood Forecast:Working Group on California Earthquake Probabilities

Paleoseismology

Size and frequency of past earthquakes

D. P. Schwartz, USGS

Natural Hazard Assessment

1. Size, location, and likelihood of future events

2. Quantification of their impacts/secondary hazards

Bay Area Earthquake Forecast;Working Group on Earthquake Probabilities

Probabilistic hazard assessments

National Seismic Hazard Map2% chance of exceedance in 50 years(2475 yr return period)

30 yr probability of tsunami runup exceeding 0.5 m Parsons and Geist (2009)

What politicians are interested in

A couple of decades ago, a California congressman asked a seismologist three simple questions:

What is the scope of the earthquake problem in California?

What can we do about it?

How much will it cost?

Risk – occurrence of an event and its consequences

Hazard Exposure Risk

$ losses

#

fatalities

#

displaced

Social and

economic

disruption

Vulnerability

Physical event, its impacts, and collateral (secondary) hazards

Assets at Risk- population, buildings, infrastructure, ecosystems

Susceptibility to damage, disruption and other adverse consequences due to physical impacts

What is Resilience?

“The ability to prepare and plan for, absorb, recover from, or more successfully adapt to actual or potential adverse events”

Photo: Cedar Rapids, Iowa during the 2008 flooding

Source: AP photo/Jeff Robertson

2012, Free PDF available at National Academies Press, www.nap.edu

Components of resilience

Physical resilience- The foundation:

Zoning/bldg. codesRetrofitsLevees

Social resilience - The engine:

Personal responsibilityCommunity engagementStrong social networksStrong & diverse economyGood governance and political will

Resilience

A TALE OF RESILIENCE …

Disasters

from

around

the world

Bold Leadership

Heroes and a Villain

Creative Solutions

Community Activism

The CAPSS Project – and a true hero

CAPSS = Community Action Plan for Seismic Safety for San Francisco

Brainchild of Laurence Kornfield, Chief Building Inspector

Saw 1995 Kobe, Japan EQ first-hand and recognized it as his worst nightmare

Purpose: To help San Franciscans make good decisions to reduce the City’s earthquake risk

The CAPSS Project – a tale of three mayors

CAPSS - a project of the San Francisco Dept. of Building Inspection, overseen by Building Inspection Commission

Included a Citizen’s Advisory Committee Started 2001 to 2003 – CANCELLED! Resumed 2008 to 2010

“There will be no earthquakes while I am Mayor of SF”

Mayor Willie Brown

Mayors Newsome and Ed Lee

Jason Elliott

CAPSS: Unique undertaking – vulnerability assessment at neighborhood scale

Community Action Plan for Seismic Safety

Used HAZUS software on neighborhood scale inventory with specific vulnerability functions for SF buildings

Examined 4 earthquake scenarios

San Andreas M6.5San Andreas M7.2San Andreas M7.9

Hayward M6.9

Maps of shaking intensity for the 4 CAPSS scenarios

All produce shaking throughout SF 2-4 times stronger than shaking in Marina during 1989 Loma Prieta quake

Exposure: Building Use & Type, total = 160,000

Building Use

Sin-gle-fam-ily

69%

2 unit res.12%

3+ unit res.14%

Other res.0%

Comm.3% Indust.

1%

Structural type

WF SS res

53%Conc. <1980

2%

WF nonSS res43%

Mod. Conc.0%

Steel Mom.1%

Unref. Mason.

1%

WF = Wood FrameSS = Soft StoryRes = ResidentialComm = CommercialInd = Industrial

96% Residential 55% of Concern

San Francisco’s special vulnerability

SF second only to NYC in % of households that rent, ~66%

~70% subject to rent control

50% residential structures built prior to 1930

84% residential structures built prior to 1970

Extensive soft-story construction

Post-Earthquake Functionality of Dwelling Units after M7.2

Usable, light

damage

Usable, moderate damage

Repairable, cannot be occupied

Not repairable, cannot be occupied

120,000 130,000 74,000 11,000

85,000 units unusable X 2.31 people/household = 196,300 homeless

THSan Francisco Planning and Urban Research

1906 Centennial commemorationKatrina shelters

TH

Goals : establish performance goals for the "expected"

earthquake that support resilience define transparent performance measures to reach

performance goals suggest next steps for San Francisco's new buildings,

existing buildings and lifelines.

San Francisco Planning and Urban Research

1906 Centennial commemoration

Katrina shelters

21

22

GOALS

1. Residents will be able to stay in their homes

2. Residents quickly have access to privately-run community services

3. No building will collapse catastrophically

4. Businesses and the economy will quickly return to functionality

5. City’s sense of place preserved

CAPSS Policy Recommendations

Estimated share of housing units unoccupiable, by structural types - M 7.2 San Andreas scenario

1 & 2 unit wood frame soft-story residences, 22%

3 & 4 unit wood frame soft-story residences; 34%

5 & more unit wood frame res-idences with 3 or

more stories; 33%

Concrete build-ings built before

1980; 6%

All other types of build-ings; 5%

3 step strategy to reduce risk to all privately-owned buildings

Step 1: Encourage retrofits, facilitate market in which EQ performance valued

Step 2: Require evaluations & notification

Step 3: Require retrofits

A generational program to address all vulnerable building types

Building Categories 2010-2015

2015-2020

2020- 2025

2025-2030

2030-2035

2035-2040

Wood frame residential buildings with three or more stories and five or more units** Concrete tilt-up buildings Residential buildings with three and four units Private K-12 schools and private universities Assisted living facilities Concrete residential buildings built before 1980 Other types of residential buildings with more than five units Hotels and motels serving tourists Critical retail stores and suppliers Single family homes and two unit residences Concrete non-residential buildings built before 1980 Houses of worship Preschools and daycare centers Buildings used by large audiences Historic buildings Large buildings with welded steel moment frames built before 1994 Early retrofitted buildings All other building types Color key Step 1: Facilitate a market in which earthquake performance is valued Step 2a: Nudge market by requiring evaluation upon sale Step 2b: Nudge market by requiring evaluation by a deadline Step 3: Implementation period to require retrofit by a deadline

Success!!

April 18, 2013 Mayor Lee signs into law, new ordinance for mandatory inspection and retrofit for 5+ units, 3+ story soft-story buildings permitted for construction prior to Jan. 1, 1978

Patrick Otellini – Earthquake Safety Implementation Program, SF’s Chief Resilience Officer

Retrofit Solution Enforcement

“Earthquake Warning

This building is in violation of the requirements of the San

Francisco Building Code regarding earthquake

safety."

Posted on the building, can not be removed until building is in compliance

Recorded with the title of the building

Disappointment: Annual tenant notification not required

Approach – “My grandmother lives in the building and my uncle owns it.”

Simple template inspection to determine soft-story condition, ~$500

Strengthening on ground floor only

30

Critical infrastructure – impetus from 1989 Loma Prieta earthquake

31

In the 25 years since Loma Prieta ….

Infrastructure provider

Number clients served

Scope of upgrades Total cost/source of funding

Pacific Gas and Electric (PG&E)

15M throughout N CA

System upgrade of underground gas, electrical components, substations, and admin building.

$2.5Brate payers

Bay Area Rapid Transit (BART)

400,000 daily ridership

Retrofit core system-aerial structures, stations, transbay tube (completion system 2018, tube 2023)

$1.3Bbonds & taxpayers/

$3M from FEMA

East Bay Municipal Utilities District(EBMUDD)

1.3M in East Bay

Entire system upgrade: pipelines, fault crossings, dams, admin building, pumping and treatment plants (completed 1999?)

$0.19Brate payers

California Department of Transportation (CALTRANS)

38.3M state-wide

Structurally upgraded and seismically retrofit over 2000 bridges and overpasses, new E span Bay Bridge

$13.08BCA taxpayers

San Francisco Public Utilities Commission(SFPUC)

2.6 M residential, commercial, and industrial

Upgrade of 100+ yr old Hetch Hetchy water system-pipelines, fault crossings treatment facilities, and reservoirs (2016 completion)

$4.6Bbond measure

Total Investment $21.6B

Five step resilience strategy

Assess vulnerabilities to expected earthquakes

Set performance goals for the systems after the earthquake

Communicate risks/benefits and secure funding

Develop creative and innovative solutions for these complex problems. – Include redundancy into the system

Continue to reassess system performance as upgrades proceed. – Develop real-time damage assessment

capability using USGS ShakeMaps overlain by system fragility functions.

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carrier pipei.d: 6ft; length: 85ft

Key element’s SF’s resilience success

Widespread risk awareness– USGS forecast

– Loma Prieta, Kobe, Katrina

Champions!

Detailed vulnerability assessment

Engagement of stakeholders– CAPSS Citizen Adv. Comm.

– SPUR policy think tank

Plain English resilience performance objectives

Creative solutions and equity – a plan all vulnerable buildings in city

“Chance favors the prepared mind”

Bold leadership, citzenry willing to tax themselves for public good

Step 1: Encourage retrofits

Step 2: Require evaluations & notification

Step 3: Require retrofits

Final comments

Earth Scientists are convinced if they just explain the hazards to public, then they will take responsible action

At best, we assume if they can demonstrate cost-effectiveness, then policy makers will act

…

Risk reduction and resilience requires a truly interdisciplinary approach

Resilience is community-based and involves a number of critical elements

Insurance as a resilience strategy

Typically, homeowner or business pays a premium annually for coverage for loss

For floods, fires have thousands of claims annually, easy to determine premium

For rare natural hazards, rely on “catastrophe models” of risk and loss

Payout for claim is always less a “deductible”, typically 15% for natural hazards, policy may cover temporary living expenses

Even if home unlivable, owner still responsible for mortgage

Earthquake insurance – does the math make sense?

2500 square foot home Construction price in Bay

Area $400/square foot Home value = $1 million CA EQ Authority premium

in 94305 = $4000K/yr Earthquake after 10 years:

– $40K in premium

– 15% deductible = $150K

Home must sustain $190K in damage before you get anything back from insurance!