A proposal for mutual-aid-type distributed evacuation based on residents’ evacuation intentions in a hilly and mountainous area of Japan

Flooding and landslide disasters caused by typhoons and heavy rains occur annually in many parts of the world. It is advisable to evacuate to safe places in advance when there is an imminent risk of a disaster. Delayed evacuation is a challenging problem that has been addressed in several studies. This study proposes a mutual-aid-type distributed evacuation policy that effectively utilizes limited community resources available for support in hilly and mountainous areas. Since hilly and mountainous areas often have well-formed communities, they have the potential to develop evacuation plans tailored to the region's actual conditions and its residents, with a focus on mutual aid, while accommodating limited resources. First, semi-structured interviews were conducted using open-ended questions with almost all residents in the study area, which is a hilly and mountainous area in Japan. Based on the results of these surveys, this study clarified the evacuation intentions of residents and identified the community resources. Furthermore, this study proposes a mutual-aid-type distributed evacuation as a suitable evacuation policy for the study area, and verifies its feasibility through a simplified evacuation simulation. In addition, this study discusses the potential for its application in other hilly and mountainous areas in Japan. In the future, as society matures and the population concentrates in urban areas, the number of aging communities is expected to increase. The mutual-aid-type distributed evacuation proposed in this study will contribute to an evacuation policy suitable for such societies.