lessons learned from past notable disasters part iii d: china landslides

LESSONS LEARNED FROM PAST NOTABLE DISASTERS

PART III D: CHINALANDSLIDES

Walter Hays, Global Alliance for Disaster Reduction, Vienna,

Virginia, USA 

NATURAL HAZARDS THAT PLACE CHINA’S NATURAL HAZARDS THAT PLACE CHINA’S COMMUNITIES AT RISK COMMUNITIES AT RISK

NATURAL HAZARDS THAT PLACE CHINA’S NATURAL HAZARDS THAT PLACE CHINA’S COMMUNITIES AT RISK COMMUNITIES AT RISK

FLOODS

TYPHOONS

EARTHQUAKES

LANDSLIDESS

DROUGHT EPISODES

GLOBAL CLIMATE CHANGE

ENACT AND IMPLEMENT POLICIES HAVING HIGH BENEFIT/COST FOR COMMUNITY RESILIENCE

ENACT AND IMPLEMENT POLICIES HAVING HIGH BENEFIT/COST FOR COMMUNITY RESILIENCE

GOAL: DISASTER GOAL: DISASTER RESILIENCERESILIENCE

GOAL: DISASTER GOAL: DISASTER RESILIENCERESILIENCE

CHINA’SCHINA’S

COMMUNITIESCOMMUNITIES

CHINA’SCHINA’S

COMMUNITIESCOMMUNITIESDATA BASES DATA BASES AND INFORMATIONAND INFORMATIONDATA BASES DATA BASES AND INFORMATIONAND INFORMATION

HAZARDS: GROUND SHAKING GROUND FAILURE SURFACE FAULTING TECTONIC DEFORMATION TSUNAMI RUN UP AFTERSHOCKS

•LANDSLIDE HAZARDS•BLDG. INVENTORY•VULNERABILITY•LOCATION

LANDSLIDE RISK LANDSLIDE RISK

RISK

ACCEPTABLE RISK

UNACCEPTABLE RISK

GOAL: LANDSLIDE GOAL: LANDSLIDE DISASTER RESILIENCEDISASTER RESILIENCE

• PREPAREDNESS•PROTECTION•EARLY WARNING•EMERGENCY RESPONSE•RECOVERY and RECONSTRUCTION

POLICY OPTIONSPOLICY OPTIONS

POLICY POLICY ADOPTIONADOPTION

POLICY POLICY ADOPTIONADOPTION

RISK ASSESSMENT

• VULNERABILITYVULNERABILITY

• EXPOSUREEXPOSURE

• EVENTEVENT

POLICY ASSESSMENT

• COSTCOST

• BENEFITBENEFIT

•CONSEQUENCESCONSEQUENCES

TOWARDS LANDSLIDE DISASTER TOWARDS LANDSLIDE DISASTER RESILIENCERESILIENCE

LAND-SLIDESLAND-SLIDESLAND-SLIDESLAND-SLIDES EXPECTED EXPECTED LOSSLOSS

EXPECTED EXPECTED LOSSLOSS

MAP OF CHINA’S PROVINCES

LANDSLIDES

LARGE VOLUME LANDSLIDES OCCUR IN ASSOCIATION WITH AN EARTHQUAKE’S

GROUND SHAKING OR A TYPHOON’S RAINFALL

M8.0 BEICHUAN EARTHQUAKE GENERATED LARGE VOLUME

LANDLIDES

2:30 PM LOCAL TIME

MAY 12, 2008

BEICHUAN, CHINA EARTHQUAKE: MAY 12, 2008

PHYSICAL CHARACTERISTICS OF THE EARTHQUAKE

• Epicenter was located 100 km (60 miles) from Chengdu, the provincial capital, which is on edge of the Tibetan foothills and home to about 10 million people.

• This earthquake occurred on a well known fault zone, which has generated destructive earthquakes in the past (e.g., on 25 August 1933).

CHANGDU, 100 KM FROM EPICENTER

COMPARISON WITH 1976 TANGSHAN EARTHQUAKE

• The Beichuan earthquake was more than 2 x larger than the July 28,1976 Tangshan earthquake, which caused 255,000+ deaths.

EMERGENCY RESOURCES

• More than 20,000 military personnel were ordered immediately to assist in high-damage areas.

• The number was increased substantially to deal with the “earthquake lakes.”

SOCIETAL IMPACTS OF THE LANDSLIDES

• Some roads were impassable because of landslides, which hindered search and rescue,---

• but, worst of all, 69 unique “earthquake lakes” were created by the landslides in mountainous regions.

SITING AND BUILDING ON UNSTABLE SLOPES

LANDSLIDESLANDSLIDES

SOIL AND ROCK SUCEPTIBLE TO FALLS

SOIL AND ROCK SUCEPTIBLE TO TOPPLES

SOIL AND ROCK SUCEPTIBLE TO SPREADS

SOIL AND ROCK SUSCEPTIBLE TO FLOWS

PRECIPITATION THAT TRIGGERS SLOPE FAILURE SHAKING

GROUND SHAKING THAT TRIGGERS SLOPE FAILURE

CAUSES OF DAMAGE

CAUSES OF DAMAGE

CASE HISTORIESCASE HISTORIES

LANDSLIDE: JINGXIU

LANDSLIDE: HANWANG

LANDSLIDE: MIANZHU

69 EARTHQUAKE LAKES

Created by the quake-induced landslides

ONE OF 69 "QUAKE LAKES": BEI HE RIVER DAMMED BY LANDSLIDE DEBRIS

DAYS 14-17: CHINA EARTHQUAKE SURVIVORS

NOW HAVING TO COPE WITH THREAT OF FLOODS FROM

69 EARTHQUAKE LAKES

DAYS 14-17: GOVERNMENT MAKES RISK REDUCTION ON 69 "QUAKE

LAKES" A TOP PRIORITY

•Sixty-nine “Quake Lakes” created in mountainous areas by the debris from landslides appeared ready to burst their banks, and continuing rainfall was exacerbating the threat.

$29 million in emergency funds and increased military

resources were allocated for the priority effort.

DAYS 14-17: GOVERNMENT PLANS EVACUATIONS TO REDUCE RISK IF A "QUAKE LAKE" SHOULD BURST

•Authorities announced plans to evacuate more than a million people in anticipation of failure of the rock-and-mud embankments.

EVACUATION CHALLENGE

•Evacuation would have to be accomplished within one to four hours, the time for the wall of water to reach and inundate scores of cities and rural villages

that were already devastated.

BEICHUAN: 3.3 KM (2 MI) DOWN-STREAM FROM A "QUAKE LAKE"

LESSONS LEARNED FOR DISASTER RESILIENCE

• ALL NATURAL HAZARDS

• CAPACITY FOR INTELLIGENT EMERGENCY RESPONSE IS ESSENTIAL FOR COMMUNITY RESILIENCE.

FLEEING POSSIBLE FLOODING

EVACUATIONS TO ESCAPE FLOODING THREAT

EVACUATING

EVERYONE GOES

THIRTY GIANT EARTHMOVERS FLOWN IN TO QUAKE LAKES

SOLDIERS DISPATCHED TO CREATE DIVERSION CHANNELS

GOAL: A DIVERSION CHANNEL IN FIVE DAYS OR LESS

EVERY HOUR IS IMPORTANT

TANGJIASHAN, LARGEST OF 69 "QUAKE LAKES"

RISING WATER IN TANGJIASHAN CAUSES EVACUATION OF YULI, MAY 31

NO DAMAGE TO THREE GORGES DAM:1,000 KM AWAY

SOLDIERS REPAIR CRACKS IN ZIPINGPU DAM:DUJIANGYAN

LESSONS LEARNED FOR DISASTER RESILIENCE

• ALL NATURAL HAZARDS

• CAPACITY FOR RECOVERY AND RECONSTRUCTION IS ESSENTIAL FOR COMMUNITY RESILIENCE.