Rick Wilson, California Geological Survey

Probabilistic Tsunami Hazard Analysis and Public Policy

Partners =

Community

StateFederalNational Tsunami Hazard

Mitigation Program

California Tsunami Steering Committee

CA Office of Emergency ServicesCA Geological Survey

20 coastal counties

California Tsunami Policy Work Group

Tsunami Warning Centers

and Regional National Weather Service Forecast Offices

Coordinating CommitteeMapping and Modeling Subcommittee

Mitigation and Education SubcommitteeWarning Coordination Subcommittee

Evacuation/Emergency response planning

Maritime planning

Land-use planning

Recovery planning

www.tsunami.ca.gov

Tsunami Hazard Mitigation Program Projects in California

California Seismic Hazard Mapping Act: Project–level assessment and real-estate disclosure

Expert Work Group assisting in review of pilot study work in Crescent City and Huntington Beach

Initial probabilistic modeling completed by URS Corp. and Univ. of Washington in parts of California

Initial findings completed and report being generated

Guidance on application will come from California Tsunami Policy Work Group

A second phase of work and mapping is being initiated

Status of Probabilistic/Land-use Mapping in CA

Crescent City

Huntington Beach

Initial Findings of CA-PTHA Work Group

PTHA in California scientifically feasible and appropriate for use

Tsunami model and map results are most sensitive to source characterization, especially fault slip/uplift amount

Alignment with formal Probabilistic Seismic Hazard Analysis vital, especially for national production of consistent products (building code, policymakers, and NTHMP)

Application of probabilistic analysis will improve the understanding of the tsunami risk, as long as:

input parameters are correct uncertainties are well understood and

translatable products are accurate, consistent, and

easy to understand

P R E L I M I N A R Y

URS Consultants, 2012 for Caltrans/PEER/CGS

Probabilistic Tsunami Hazard Analysis in Crescent City; blue line

is 2009 state inundation map line

Uses for Probabilistic Tsunami Hazard AnalysisOur concept: Produce single set of risk maps/products for multiple uses

› Project–level assessment and real-estate disclosure (CGS-Seismic Hazard Mapping Act)

› Land-use planning (communities, CA Coastal Commission)

› Standardized hazard analysis for evacuation planning (Cal-OES)

› Building design and construction , critical facilities (ASCE, Uniform/ International Building Code, Nuclear Regulatory Commission)

› Flood protection and insurance (FEMA, Risk MAP, CA-Dept. of Water Resources)

› Input for consistent risk analysis and damage estimates (HAZUS)

Preliminary risk levels for different applications

Preliminary products for different applications

PILOT STUDIES•Probabilistic Hazard •Community Analysis

•Maritime Products

Implementation

TSUNAMI SCENARIO

•Vulnerability Analysis•Social & Economic•Structural Damage

Impact

POLICY WORKING GROUP

•Land Use – Construction•Emergency Management

•Recovery

Issues

POLICY MAKERSGuidance - Regulations

• Local• State

• Federal

Action

(Soft) (Hard)

Formed in October 2011 to address issues for both the state tsunami program and the USGS tsunami scenario project called “Science Applications for Risk Reduction” (SAFRR)

Work Group is a voluntary advisory board comprised of state, federal, and local government representatives, as well as private organizations with interest in coastal planning

Charged with identifying, evaluating and making recommendations to resolve issues preventing full and effective implementation of tsunami hazard mitigation and risk reduction at a local level

Work Group has evaluated the status of tsunami hazard assessment, preparedness, mitigation, response, and recovery activities in the state and identified the needs to sustain existing programs or implement new programs

California Tsunami Policy Work Group

Figure from Real and others, 2012

California Tsunami Policy Work GroupNotable Federal and State Legislation and Programs

(from Johnson and Real, 2013)

FEDERAL LEGISLATION

Tsunami Warning and Education Act of 2006 (preparedness and mitigation)

Coastal Zone Management Act of 1972 (planning)

Disaster Mitigation Act of 2000 (mitigation)

Stafford Disaster Relief and Emergency Assistance Act (mitigation and recovery)

STATE PROGRAMS

California Tsunami Preparedness and Hazard Mitigation Program (hazard assessment, preparedness, mitigation, response)

California Tsunami Policy Work Group (policy and planning)

Safety Element in Local General Plans (planning)

California Coastal Commission (planning)

California Building Standards Code (mitigation)

FEDERAL PROGRAMS

National Tsunami Hazard Mitigation Program (preparedness, mitigation, response)

TsunamiReady Program (preparedness)

National Response Framework (response)

National Disaster Recovery Framework (recovery)

FEMA Flood Insurance Rate Maps and RiskMAP (mitigation and recovery)

STATE LEGISLATION

Seismic Hazard Mapping Act of 1990 (mitigation)

California Coastal Act of 1976 (mitigation and planning)

California Oil Spill Prevention and Response Act of 1990 (recovery – environmental)

NOTE: Tsunami specific in red

California Tsunami Policy Work GroupPossible Courses of Action

(from Johnson and Real, 2013)

Ensure continued funding and support for the National Tsunami Hazard Mitigation Program, TsunamiReady and affiliated state and local programs.

Develop a coordinated and sufficiently robust policy framework for tsunami hazard assessment and mitigation planning for California coastal communities, ports and harbors.

Explore opportunities to advance multi-hazard mitigation planning along California’s coast and bays to more holistically address issues of future tsunami risk, sea level rise and future coastal flooding and erosion, and earthquake-induced liquefaction.

Encourage responders and government managers at all levels to conduct self-assessments, devise table-top exercises, and more carefully consider how the short-fuse intensity and wide geographic scale of tsunami scenarios could challenge current assumptions.

Work to address recovery challenges likely for the most vulnerable coastal communities, ports and harbors, as well portions of the state’s fishing and agriculture sectors.

Transferability of Ideas/Policies

Hazard Assessment

Preparedness

Mitigation

Response

RecoveryIs commitment to pre-disaster planning for

post-event recovery in California and U.S.

adequate?

Dis

aste

r C

ycle

Reconstruction Design Council in Response to the Great East Japan Earthquake, June 2011

Sendai Plain

Santa Cruz