A tsunami exceeding three feet in height can cause a number of infrastructure problems. These include technological emergencies like fire, explosion, or release of hazardous materials. Damage caused by the water can disrupt services or utilities like water, gas, sewer or electrical service. It is important to think about the steps necessary for tsunami recovery and reconstruction.
The physical energy of a tsunami can directly damage a structure and flooding by water will bring its own form of damage to the contents of a building. The impact of a tsunami to a community will be based in part on which structures are affected by the wave. Loss of a clinic, hospital, school or shelter because of a tsunami would decrease a community’s ability to cope effectively with the incident. Tsunami can also cause damage to wildlife habitat like coral reefs and erode coastlines.
In general, the areas at greatest risk from tsunami damage are found at elevations below 100 feet and/or within one mile of the shoreline.
Damage Assessment – The transition or rehabilitation phase of a disaster immediately follows the emergency stage of an incident. The efforts needed to restore normality depend on an assessment being made to record damage to public and private property. Damage assessments allow resources to be prioritized to repair vital infrastructure, institute temporary repairs and recovery measures taken will allow people to return to work.
Damage from a tsunami can take the form of direct damages, indirect damages from loss of productivity and macroeconomic damage to the overall region. Initial assessment of direct damage would be the first step taken in rehabilitation phase of a disaster.
The Incident Command System (ICS) has been adopted in the United States for use in managing incidents like a tsunami. Under ICS, a Damage Assessment Coordinator is assigned to incident management to conduct assessment of damage to all buildings in the affected area. Assessments are made under a set of priorities.
An immediate assessment is made of critical facilities like fire stations, hospitals and public utility infrastructure. An Initial Damage Assessment (IDA) is made of public and private property, typically through use of a drive-by inspection. The goal of the IDA is to determine the magnitude of damage incurred because of the tsunami or other natural disaster. As time permits, a more thorough Preliminary Damage Assessment (PDA) is made to provide better estimates of loss values needed in making formal disaster declarations to state and federal government agencies.
Personnel suited for filling the Damage Assessment Coordinator position or serving on a damage assessment team are people like building inspectors, structural engineers and commercial contractors. The following is the recommended minimum training for Damage Assessment personnel in the ICS to compliment their professional experience:
- IS-100.a Introduction to the Incident Command System
- IS-200.a ICS for Single Resources and Initial Action Incidents
- IS-700.a An Introduction to NIMS
- IS-800.b An Introduction to the National Response Framework (NRF)
Needs Assessment – Damage Assessment Teams, along with other response personnel, need to remain observant of public safety needs that arise after the impact of a tsunami. The obvious example is protection of life. People in immediate danger due to injuries or their circumstances need to be rescued, stabilized and transported to the appropriate treatment and care facilities.
The United Nations Environment Program (UNEP) has established a set of guiding principles for post-tsunami rehabilitation and reconstruction known as the Cairo Principles. Addressing the needs of people affected by a tsunami are a significant part of this document.
UNEP urges early resettlement of people affected by a tsunami to safe housing, removal of flood debris, making provision for safe water and sanitation, and providing access to people’s livelihoods. Addressed later here in mitigation, the UNEP recommends relocation be made to safer, higher ground.
The World Health Organization (WHO) has looked at the vital needs associated with a tsunami recovery that look at a percentage of desired outputs. Vital needs that need to be observed and measured are:
- Population access to safe water, basic sanitation and food aid
- Household food consumption
- Population with damaged housing living in emergency shelters, temporary housing or in new housing
- Hospital beds and outpatient services available to population
- Miles of roads, numbers of bridges repaired and harbor rehabilitated
- Employment, self-employment and employment in the informal economy
Many needs can be measured by direct observation. Use of a household survey instrument can also provide core indicators of community needs.
Mobilization and Organization for the Planning Process and Implementation
Stakeholders – One idea suggested by FEMA is the identification and composition of a disaster recovery and reconstruction task force prior to ever needing it in the field. Potential representatives can come from local government leadership, legislators, public safety officials, public works and planning employees, transportation workers, utility operators, animal control offices, public school officials, risk management or insurance representatives, tourism interests, port directors or harbormasters, public health practitioners, and community business members.
Once this group is established and has had a chance to review local planning efforts, they should think about who else is missing from the group.
Managing information – Information can de derived from a remarkable number of sources found throughout a community. Initially, local emergency response agencies should have a communications system in place based on the common terminology stressed by use of ICS. Planning information can be obtained through
- The Press
- Maps and as-built drawings of buildings
- Drive-by inspections and reconnaissance missions
- Surveys that can include household data, interviews of businesses, and follow on damage assessments
- Secondary analysis of existing data like tax, census information or existing flood management plans
- Interpersonal communications with community members and emergency responders
- Remote sensing equipment like flood gauges, seismometers, aerial photography and satellite imagery
Community Involvement – One important element found in NOAA’s TsunamiReady Program is concept of community development. A community that seeks certification as being TsunamiReady has provided training in public schools on local response plans and has attempted to engage community members in learning more about the dangers of tsunami.
The Cairo Principles encourage wide dissemination of best practices and lessons learned in tsunami preparedness to the public as information emerges. This fits into the idea of establishing recurring, regular training and presentations being made available to the public and first responders.
The reconstruction phase following the aftermath of a tsunami offers local government and community stakeholders with a unique opportunity to start from scratch and improve the living conditions experienced by residents.
Planning Process – There are many ways to plan for effective response to a tsunami. The NOAA TsunamiReady website offers some ideas. FEMA suggests establishment of a task force composed of a broad range of interests and abilities. It is suggested that there be a lead agency placed in charge of the planning effort. The task force needs to review potential hazards found in the community and propose a plan to deal with them. It is important that this draft plan be presented to the public and that consensus building is encouraged.
Once a plan is adopted, local officials need to train and exercise its use. The plan should be amended and reviewed as new lessons are learned from field experiences and actual use in an incident.
Key Elements of a Reconstruction Policy – There are some key elements found in a post-disaster and reconstruction plan. Others may arise through use of the planning task force. Key elements revolve around these themes:
- Early Response and Recovery
- Local Response Organization and Authority
- Rehabilitative Functions and Services to the Public
- Land Use Planning
- Regional Coordination of Intergovernmental Groups
Specific Policy Tools – There are several land use policy and building code schemes that can be used to implement tsunami policy-making decisions. Community participation in the national coastal zone management program is an excellent beginning. After a tsunami or other natural disaster, a community might consider a building moratorium be put into place until the effects of the incident are fully accounted. There are likely places where permanent housing should not be replaced where it was before the disaster.
Other policy tools can take the form of temporary repair permits, establishment of demolition regulations, design controls, zoning for temporary housing, density controls, use of overlay districts, and prioritization of infrastructure repairs within the community.
Recommendations for Mitigation Strategies
Built Environment – One important consideration for dealing with the consequences of a tsunami is the continuity of local emergency response organizations to operate effectively. This is best accomplished by planning the location of the local Emergency Operations Center (EOC) in a location that is deemed safe from the impact of a tsunami or other significant natural disaster. Once a safe location is identified, the location of potential backup facilities should also be considered.
Adding the concept of vertical evacuation to the built environment could improve tsunami safety. FEMA has identified the need for accommodating vertical evacuation of structures as part of the National Tsunami Hazard Mitigation Program. There are regions in the country where locally generated tsunami could wash ashore in a matter of minutes and the community would not have adequate shelters from the flood surge.
Use of a structure designed for vertical evacuation would give residents quick access to a higher, safer refuge from an impending tsunami event. Structures designed to provide for vertical evacuation need to be sited in the proper location, built to withstand the forces at play with a tsunami and provide adequate spaces for the people that need to use the facility.
Natural Environment – The Cairo Principles list the use of setbacks, greenbelts and other no-build areas as one of the overarching principles of rehabilitation using a scientifically established reference line. The concept of integrated coastal management involving the public is seen as key to protecting the environment and promoting safety.
A second suggestion would be to protect and enhance the ability of the natural environment to adsorb the impact of tsunami flood surge. This can be accomplished through protection of wetlands, preservation of natural outcroppings and sandbars from development, rehabilitation of coastal woodlands like mangrove forests, and limiting construction of dikes or other flood control structures.
Population-Based Approaches – An initial suggestion for population-based mitigation is to remember incorporation of tsunami risk assessment information into urban planning efforts and management plans developed for at risk regions. Areas of focus should include communities experiencing rapid growth and the location of permanent housing developments.
Thinking about and developing a plan for recovery and reconstruction after a tsunami is important and will save lives and livelihoods when this disaster occurs.
Copyright – 2013 by Alan Sorum.