N A Horspool, S Fraser, GNS Science (EQC funded report)
Recent tsunami events across Asia, the Pacific and South America have demonstrated the destructive potential of tsunami to the built environment. While devastating for the countries impacted, these events provide an opportunity for other countries to learn lessons from the disasters and to better prepare for future tsunami. The impacts of tsunami on the four major lifelines sectors (water, transport, energy and telecommunications) can be significant and can cause major disruptions to services, which in turn can delay emergency response and recovery efforts. However, actions can be taken to reduce the impacts through mitigation activities that increase the resilience of lifelines to tsunami. These include options such as response and recovery planning, engineering solutions to increase the performance of lifelines, or improved site selections to reduce exposure to tsunami. New Zealand has a very high tsunami hazard with local, regional and distant tsunami sources potentially affecting the country. It is therefore critical that key lifelines are resilient from the threat of tsunami.
This report is a review that consolidates the current state of knowledge of tsunami impacts to lifelines and a) summarises the damage and failure models of lifelines impacted by tsunami, b) describes what recovery actions were taken following recent tsunami by lifeline operators, and c) outlines what actions can be taken to increase the resilience of lifelines to future tsunami.
The findings of this review highlight that all lifelines can be impacted to some level by tsunami. Furthermore, the interdependency between lifelines can compound the disruption of services. For example, power outages impact wastewater operations, telecommunications and some transportation services such as airports and trains. Having operational transportation and telecommunications networks are also critical in being able to respond and recover from tsunami impacts.
Information is given in the report sections on how recovery of lifelines from tsunami was carried out from other events. Further, information is given on potential mitigation actions that can be taken by lifeline organisations to lessen the likelihood of damage and service disruption from tsunami.