lessons learned from past notable disasters algeria part 1: floods

LESSONS LEARNED FROM PAST NOTABLE DISASTERS

ALGERIAPART 1: FLOODS

Walter Hays, Global Alliance for Disaster Reduction, Vienna,

Virginia, USA 

ALGERIA

ALGERIA: AFRICA—EURASIA COLLISION

NATURAL HAZARDS THAT HAVE CAUSED NATURAL HAZARDS THAT HAVE CAUSED DISASTERS IN ALGERIADISASTERS IN ALGERIA

NATURAL HAZARDS THAT HAVE CAUSED NATURAL HAZARDS THAT HAVE CAUSED DISASTERS IN ALGERIADISASTERS IN ALGERIA

FLOODS

WINDSTORMS/DUSTSTORMS

EARTHQUAKES

LANDSLIDES

ENVIRONMENTAL CHANGE

GLOBAL CLIMATE CHANGE

HIGH BENEFIT/COST FROM BECOMING DISASTER RESILIENT

HIGH BENEFIT/COST FROM BECOMING DISASTER RESILIENT

GOAL: PROTECT PEOPLE GOAL: PROTECT PEOPLE AND COMMUNITIESAND COMMUNITIES

GOAL: PROTECT PEOPLE GOAL: PROTECT PEOPLE AND COMMUNITIESAND COMMUNITIES

Natural Phenomena that Cause Disasters

Planet Earth’s atmospheric, hydrospheric, and lithospheric interactions cause

FLOODS

A DISASTER is ---

--- the set of failures that overwhelm the capability of a community to respond without external help  when three continuums: 1)  people, 2) community (i.e., a set of habitats, livelihoods, and social constructs), and 3) complex events (e.g., floods, earthquakes, ...) intersect at a point in space and time.

Disasters are caused by single- or multiple-event natural hazards that, (for various reasons), cause

extreme levels of mortality, morbidity, homelessness,

joblessness, economic losses, or environmental impacts.

THE REASONS ARE . . .

• The community is UN-PREPARED for what will happen

THE REASONS ARE . . .

• When it does happen, the functions of the community’s buildings and

infrastructure are UNPROTECTED with the appropriate codes and standards

THE REASONS ARE . . .

• The community has NO RELIABLE WARNING SYSTEM in place

THE REASONS ARE . . .

• The community LACKS THE CAPACITY TO RESPOND to the full spectrum of emergency situations.

THE REASONS ARE . . .

• The community is INEFFICIENT during recovery and reconstruction

because it HAS NOT LEARNED from either this experience or the prior experiences.

TOWARDS FLOOD DISASTER RESILIENCE

TOWARDS FLOOD DISASTER RESILIENCE

ALGERIA’S ALGERIA’S COMMUNITIESCOMMUNITIES

ALGERIA’S ALGERIA’S COMMUNITIESCOMMUNITIES

DATA 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

•HAZARDS•INVENTORY•VULNERABILITY•LOCATION

FLOOD RISK FLOOD RISK

RISK

ACCEPTABLE RISK

UNACCEPTABLE RISK

FLOOD DISASTER FLOOD DISASTER RESILIENCERESILIENCE

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

POLICY OPTIONSPOLICY OPTIONS

HAZARDSHAZARDSHAZARDSHAZARDS

ELEMENTS OF FLOOD RISKELEMENTS OF FLOOD RISKELEMENTS OF FLOOD RISKELEMENTS OF FLOOD RISK

EXPOSUREEXPOSUREEXPOSUREEXPOSURE

VULNERABILITYVULNERABILITYVULNERABILITYVULNERABILITY LOCATIONLOCATIONLOCATIONLOCATION

RISKRISKRISKRISK

HIGH POTENTIAL LOSS EXPOSURES IN A FLOOD

A community’s people, property, essential and critical infrastructure, business enterprise, and government centers can be at high risk.

LOSS OF FUNCTION OF STRUCTURES IN FLOODPLAIN

FLOODSFLOODS

INUNDATION

INTERACTION WITH HAZARDOUS MATERIALS

STRUCTURAL/CONTENTS DAMAGE FROM WATER

WATER BORNE DISEASES (HEALTH PROBLEMS)

EROSION AND MUDFLOWS

CONTAMINATION OF GROUND WATER

CAUSES OF RISK

CAUSES OF RISK

CASE HISTORIESCASE HISTORIES

WHAT WILL HAPPEN?FLOOD HAZARDS

(AKA THE POTENTIAL DISASTER AGENTS)

WHAT WILL HAPPEN?FLOOD HAZARDS

(AKA THE POTENTIAL DISASTER AGENTS)

FLOOD HAZARDS

• TOO MUCH WATER DISCHARGED WITHIN THE DRAINAGE SYSTEM TO BE ACCOMMODATED IN THE REGIONAL WATER CYCLE

• INUNDATION

• EROSION

• SCOUR

• MUDFLOWS

LESSONS LEARNED ABOUT DISASTER RESILIENCE

ALL FLOODS PREPAREDNESS FOR ALL OF THE LIKELY FLOOD HAZARDS IS ESSENTIAL FOR DISASTER RESILIENCE

LESSONS LEARNED ABOUT DISASTER RESILIENCE

ALL FLOODS PROHIBITING THE CONSTRUCTION OF BUILDINGS AND LIFELINE SYSTEMS IN THE FLOODPLAIN IS ESSENTIAL FOR DISASTER RESILIENCE

LESSONS LEARNED ABOUT DISASTER RESILIENCE

ALL FLOODS TIMELY EMERGENCY RESPONSE IS ESSENTIAL FOR DISASTER RESILIENCE

SOME OF ALGERIA’S NOTABLE FLOODS

NOVEMBER 10, 2001

OCTOBER 1, 2008

NOVEMBER 10, 2001

IN A TIME OF POLITICAL CHANGE, DEVASTATING FLOODING FOLLOWED

2 YEARS OF DROUGHT

ELEMENTS OF THE DISASTER

• A month's rain fell in 24 hours, the heaviest recorded rainfall in 20 years, causing devastating floods and leaving over 600 dead.

ELEMENTS OF THE DISASTER

• In Algiers where a wall of water moved down the steep, narrow streets of the slum district of Bab al-Oued,.more than 500 died in the mass of mud, collapsed buildings and mangled vehicles left by the storm.

October is typically a bad month for heavy rainfall and

floods in Algeria

FLOODING IN GHARDAIA PROVINCE, ALGERIA

700 KM (435 MILES) SOUTH OF ALGIERS

OCTOBER 1, 2008

GHARDAIA, ALGERIA FLOODING; OCT 1, 2008

IMPACTS AFTER SEVERAL DAYS OF HEAVY RAIN

• Thirty dead• Fifty injured• Bridges and roads badly damaged

THE NEXT FLOOD IS INEVITABLE

THE NEXT FLOOD IS INEVITABLE

• BUT, FLOOD DISASTER RESILIENCE IS NOT AN IMPOSSIBLE DREAM!