Regional analysis for disaster mitigation in a depopulated and aged island society

Abstract

A detached island in Okinawa Prefecture is roughly typified by an island that is a tourist resort or not a tourist resort. Both types of islands have important problems. The resort islands have problems such as drought, waste disposal and succession of tradition. On the other hand, aging and a decrease in the population are progressing in islands that are not resorts. This study focused on the Tonaki Village, a small island that is not a resort. The Tonaki Island has a population of 440 with an elderly ratio of approximately 40%. According to the Okinawa tsunami and high tide assessment damage report, if an earthquake occurs off the Kume Island north of Tonaki a tsunami is predicted to arrive at this island in 16 minutes. Furthermore, the entire community will be flooded by high tide. The purpose of this study was to develop a planning system for disaster risk mitigation suitable for this region. In this paper, I clarify problems with the structure of the social network that pays attention to the support persons required at the time of a disaster by investigating the resident's daily life activities and association with neighbors.