Judging the effectiveness of mitigation packages

Decisions on investment in preparedness or mitigation options need to be seen in the context of how effective the overall preparedness or mitigation “package” is likely to be. Cost effectiveness is generally held to vary with disaster type. Relatively predictable sudden onset disasters, e.g. tropical storms, are generally worth substantial investment in such programs as wind resistant housing and flood control measures. Some aspects of mitigation for unpredictable sudden-onset disasters such as earthquakes are also good candidates for investment. Much is known about technical measures for protection, and investment is usually worthwhile to protect development projects which would become disasters in earthquakes, such as dams.

Slow onset environmental disasters, such as excess silting and flood risk enhancement (a problem in Bangladesh, for example) are more problematic in investment terms. The costs of protection are potentially very high, and high levels of investment are needed not only in infrastructure, but also in data collection, coordinated planning and decision-making, and public education. The costs of all these have to be included in any investment decision.