A questionnaire survey on policy preferences of Japanese citizens about low-probability/high-consequence disasters.(in Japanese)

Implementing public policy for the management of low-probability/high-consequence disasters is problematic. There is no implicit normative rule for setting investment priority to reduce the impact of such rare disasters, since it is difficult to recognize the benefit of the investment. Current generations have to decide and implement a policy to cope with disasters, but this would be of benefit to future generations. Thus, mitigation investment is likely to be lower than the optimal level required. Solving these problems are big policy challenges in disaster prevention and reduction. This paper aims to reveal the policy preferences of Japanese citizens about low-probability/high-consequence disasters. Data for this study was compiled through a questionnaire survey, conducted on the Internet in November 2011, to be a reference of national discussion on disaster management policy in Japan. The primary conclusion of this study is as follows: First, Japanese citizens consider earthquake disaster risk to be more uncertain since the occurrence of the Great East Japan earthquake of 2011. An increasing number of citizens support the implementation of mitigation investment uniformly throughout the nation, or decided regarding the probable damage. A comparatively smaller proportion of respondents prefer that this decision be evaluated according to the likelihood of a disaster. Since the earthquake, the citizens' preferences have shifted to ex-post assistance from ex-ante mitigation. These results would be plausible if citizens believe that disaster risk is uncertain. On the other hand, a large proportion of the respondents hope to complete disaster reduction investment within the short term, 10 years, expecting to cover most of its costs. They recognize that such investment is only effective against a disaster that occurs once in 100 years, and therefore they are aware that they have to prepare for the infrequent disasters that occur more frequently. Drastic countermeasures requiring significant expenses and time, such as land redevelopment, were not necessarily accepted. Such public opinion runs the risk that disaster management policy will be implemented in an ad hoc manner against small impact but frequently occurring events, and may not reduce disaster risk in the long run.