IMPACTS OF EARTHQUAKES ON WATER RESERVOIRS PIPELINES AQUEDUCTS

IMPACTS OF EARTHQUAKES ON WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS Walter Hays, Global Alliance for Disaster Reduction, University of North Carolina, USA

OVERVIEW OF EARTHQUAKE RISK WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS FACE DIFFERENT RISKS FROM THE POTENTIAL DISASTER AGENTS OF EARTHQUAKES

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS • Have POINT-SENSITIVE and AREA -SENSITIVE components, … • which have varying vulnerabilities when exposed to the TIME – and SPACE- DEPENDENT potential disaster agents of EARTHQUAKES.

TIME HISTORY AND SPECTRUM

RISK ASSESSMENT • EARTHQUAKES • INVENTORY • VULNERABILITY • LOCATION ACCEPTABLE RISK WATER, RESERV. , AQUEDUCTS, PIPELINES, , AND DISTRIBUTION DATA BASES SYSTEMS AND INFORMATION UNACCEPTABLE RISK GOAL: DISASTER RESILIENCE PPLICIES: FOR RESILIENT SYSTEMS HAZARDS: GROUND SHAKING GROUND FAILURE SURFACE FAULTING TECTONIC DEFORMATION TSUNAMI RUN UP AFTERSHOCKS PREPAREDNESS • PROTECTION • EMERGENCY RESPONSE • RECOVERY

ELEMENTS OF UNACCEPTABLE RISK DAMAGE; INJURIES FAILURE; DEATHS RISK LOSS OF FUNCTION ECONOMIC LOSS

SEISMICITY TECTONIC SETTING & FAULTS EARTHQUAKE HAZARD MODEL

THE BASIC FAULT MODELS Strike-Slip Reverse Normal

LOCATION OF WATER SYSTEMS IMPORTANCE AND VALUE OF SYSTEM AND CONTENTS EXPOSURE MODEL

QUALITY OF DESIGN AND CONSTRUCTION ADEQUACY OF LATERAL-FORCE RESISTING SYSTEM VULNERABILITY MODEL

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS • Vulnerability is a function of materials, age, maintenance, and the system’s exposure as a site-specific, or a spatiallydistributed above-or-belowground system.

CONSTRUCTION MATERIALS HAVE DIFFERENT VULNERABILITIES TO GROUND SHAKING ST ON E RI CK OR 30 ON RY , B 25 M AS AL RE I NF OR CE D 20 15 UN MEAN DAMAGE RATIO, % OF REPLACEMENT VALUE 35 E ET R C ED RC 10 I RE 5 IT W ED RC CE VII INTENSITY A DW OR NF I RE C FO VI S LL W E TE AM R E F L CR EE ON ST EIN V RE ITH O NF OR W UN N CO R 0 H F IN D CE LS M ALL L ETA & VIII D WOO ME FRA IX

COMMENTS ON DAMAGE • MMI VI DENOTES TO ONSET OF DAMAGE DUE TO LIQUEFACTION • MMI VII DENOTES DAMAGE FROM CRACKING; APPROXIMATELY 12% g • MMI VIII DENOTES SEVERE DAMAGE, TYPICALLY AT JOINTS OF PIPES; APPROXIMATELY 25 % g • MMI IX DENOTES VERY HEAVY DAMAGE, MANY BREAKS/KM; 50 %^ g.

FAULT RUPTURE DAMAGE/LOSS EARTHQUAKE GROUND SHAKING DAMAGE/LOSS TSUNAMI DAMAGE/ LOSS TECTONIC DEFORMATION DAMAGE/ LOSS FOUNDATION FAILURE DAMAGE/ LOSS SITE AMPLIFICATION DAMAGE/ LOSS LIQUEFACTION DAMAGE/ LOSS LANDSLIDES DAMAGE/ LOSS AFTERSHOCKS DAMAGE/ LOSS FIRE DAMAGE/ LOSS

CAUSES OF DAMAGE INADEQUATE RESISTANCE TO HORIZONTAL GROUND SHAKING SOIL AMPLIFICATION PERMANENT DISPLACEMENT (SURFACE FAULTING, LIQUEFACTION & LANDSLIDES) EARTHQUAKES “DISASTER LABORATORIES” IRREGULARITIES IN ELEVATION AND PLAN, AND [OOR ROUTE TSUNAMI IMPACTS POOR DETAILING AND WEAK CONSTRUCTION MATERIALS FRAGILITY OF NON-STRUCTURAL ELEMENTS

EXAMPLES OF FAILURES (AND ALMOST FAILURES) IN PAST EARTHQUAKES

INADEQUATE SEISMIC DESIGN PROVISIONS (I. E. , BUILDING CODES ) MEAN 1) INADEQUATE RESISTANCE TO HORIZONTAL GROUND SHAKING 2) COLLAPSE AND FAILURE OF ABOVE-GROUND SYSTEMS

UNDERGROUND PIPELINES AND DISTRIBUTION SYSTEMS NEED PROTECTION • A UTILITY CORRIDOR IS VULNERABLE TO LOSS OF FUNCTION WHEN IT IS ROUTED THROUGH SOILS THAT ARE SUSCEPTIBLE TO LIQUEFACTION. (USA 1995)

INADEQUATE SEISMIC DESIGN PROVISIONS (I. E. , WATER SYSTEM STANDARDS) AND THE ROUTING) MEAN 1) SUSCEPTIBILITY TO PERMANENT GROUND FAILURE (LIQUEFACTION, LANDSLIDES), 2) FAILURE OF BELOW-GROUND SYSTEMS

ABOVE-GROUND SYSTEMS NEED PROTECTION FROM LANDSLIDES • RESEVOIRS ARE SUSCEPTIBLE TO LANDSLIDES INDUCED BY EARTHQUAKES. (CHINA 2008)

AQUEDUCTS: ABOVE-GROUND SYSTEMS THAT CARRY WATER FROM “A” TO “B” • AQUEDUCTS ARE SUSCEPTIBLE TO LANDSLIDES INDUCED BY EARTHQUAKES. (ARIZONA);

AQUEDUCTS: ABOVE-GROUND SYSTEMS THAT CARRY WATER FROM “A” TO “B” • ELEVATED AQUEDUCTS ARE VERY SUSCEPTIBLE TO GROUND SHAKING.

CHINA 2008: RESERVOIRS NEED PROTECTION IN AN EARTHQUAKE

JAPAN 2011: ABOVE GROUND SYSTEMS NEED PROTECTION IN AN EARTHQUAKE

SICHUAN, CHINA: ABOVE GROUND SYSTEMS NEED PROTECTION

HAITI 2010: ABOVE-GROUND SYSTEMS NEED PROTECTION

TURKEY 2010: ABOVE GROUND SYSTEMS NEED PROTECTION

KEY CONSIDERATIONS FOR PROTECTIVE DESIGN AND SMART ROUTING WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS • Above-ground siting makes waterreservoirs and aqueducts more vulnerable to earthquake ground shaking than the buried pipelines and distribution systems are.

EARTHQUAKE SCENARIOS A DISASTER RISK ASSESSMENT TECHNIQUE FOR USE IN AN EARTHQUAKEPRONE AREA

DESIGN SCENARIOS • Distributed Systems: The risks need to be assessed in terms of regional ground shaking and ground failure maps; -- • Non-distributed systems: Assess risks in terms of sitespecific criteria.

EXAMPLE: PROBABILISTIC GROUND SHAKING HAZARD MAPS PGA: 10 % P(EXCEEDANCE) IN 50 YEARS SOURCE ØGLOBAL SEISMIC HAZARD ASSESSMENT PROGRAM ØUS GEOLOGICAL SURVEY

MAPS = INTEGRATED KNOWLEDGE A probabilistic ground shaking hazard map integrates physical properties determined from geology, geophysics, and seismology in a consistent way to define: 1) Seismic source zones 2) Regional seismic wave attenuation rates

SEISMIC SOURCE ZONES AND ATTENUATION RATES • Seismic Source Zones: Each zone has its own unique spatial and temporal distribution of faults, magnitudes and recurrence intervals. • Regional Seismic Attenuation Rates: seismic waves decay more rapidly near a plate boundary than far from the boundary.

GROUND SHAKING HAZARD ASSESSMENT SESMIC SOURCES ATTENUATION RECURRENCE PROBABILITY

WHAT DOES THE MAP SHOW? Each map shows relative levels of the ground shaking hazard on a small scale in terms of the mapping parameter: peak ground acceleration (and sometimes MMI).

PEAK GROUND ACCELERATION Peak ground acceleration correlates best with the shortperiod asymptote of the response spectrum, and is related to how a short waste water facility would respond to ground shaking.

BEST APPLICATION The maps are most useful for small-scale applications such as comparison of the relative ground shaking hazard between the endpoints of a long, distributed water pipeline system.

LIMITATIONS OF MAPS • The mapping parameter, peak ground acceleration, is not as good a descriptor of how the ground actually shakes as is a time history • The response spectrum of a time history is an approximation of how a water system element might respond to ground shaking of a certain period.

LIMITATIONS OF THE MAPS • The regional-scale peak ground acceleration maps are not appropriate for site-specific design.

LIMITATIONS OF THE MAPS • Regional maps do not incorporate information on soil properties (e. g. , shear wave velocity; data related to liquefaction; slope stability). • Soils data require sampling and mapping on a larger scale.

PGA SCALE FOR MAPS Afghanistan http: //www. seismo. ethz. ch/gshap/eastasia/

PGA MAP: USA

PGA MAP: ALASKA

PGA MAP: MEXICO

PGA MAP: CARIBBEAN

PGA MAP: SOUTH AMERICA

PGA MAP: EUROPE

PGA MAP: MIDDLE EAST

PGA MAP: INDIA

PGA MAP: EASTERN ASIA

PGA MAP: CHINA

PGA MAP: JAPAN

PGA MAP: NORTHERN AFRICA

PGA MAP: AFRICA

PGA MAP: AUSTRALIA

PGA MAP: NEW ZEALAND

RISK ASSESSMENT LEAD TO POLICY IMPLEMENTATION RISK ASSESSMENT • VULNERABILITY • COST • EXPOSURE “WATER SYSTEMS” • EVENT EXPECTED LOSS • BENEFIT • CONSEQUENCES POLICY ASSESSMENT RESILIENT SYSTEMS