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

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

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

EARTHQUAKE HAZARD MODEL EARTHQUAKE HAZARD MODEL SEISMICITY TECTONIC SETTING & FAULTS TECTONIC SETTING & FAULTS

THE BASIC FAULT MODELS Strike-Slip Reverse Normal

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

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

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 spatially- distributed above-or-below- ground system.

UNREINFORCED MASONRY, BRICK OR STONE REINFORCED CONCRETE WITH UNREINFORCED WALLS INTENSITY REINFORCED CONCRETE WITH REINFORCEDWALLS STEEL FRAME ALL METAL & WOOD FRAME VVIVIIVIIIIX MEAN DAMAGE RATIO, % OF REPLACEMENT VALUE CONSTRUCTION MATERIALS HAVE DIFFERENT VULNERABILITIES TO GROUND SHAKING

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.

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

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

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 DISTRIB- UTION 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

Above-ground siting makes water- reservoirs 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 EARTHQUAKE- PRONE 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 site- specific criteria.

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

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: 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 ATTENUATION SESMIC SOURCESRECURRENCEPROBABILITY

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 short- period asymptote of the response spectrum, and is related to how a short waste water facility would respond to ground shaking.

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

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.

The regional-scale peak ground acceleration maps are not appropriate for site-specific design.

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

RESILIENT SYSTEMS RISK ASSESSMENT VULNERABILITYVULNERABILITY EXPOSUREEXPOSURE EVENTEVENT POLICY ASSESSMENT COSTCOST BENEFITBENEFIT CONSEQUENCESCONSEQUENCES RISK ASSESSMENT LEAD TO POLICY IMPLEMENTATION “WATER SYSTEMS” EXPECTED LOSS