山間地域における豪雨災害時の住民避難

2004年9月台風21号三重県宮川村災害の事例

抄録

This paper examines the circumstance of evacuating residents during water induced disaster in the Miyagawa Village, Taki County in Mie Prefecture on September 29 th, 2004, based on field research, interviews and questionnaires conducted among them. Most hamlets in this village are located on terrace or shelving planes developed along the Miyagawa river. Thus, roads along the river provide refuge passages. Unfortunately, these passages had become impossible to be used on the evacuation due to debris and sediment on the road, collapse of the road side, inundation caused by the swelling of the river, inundation affected by both bridge and driftwood, and aggradation in the tributary caused by a lowering in tractive force due to the water level raising. The interviews conducted with residents proved that knowledge about the warning signals of such disasters is important. However, early evacuation is still more important because “high risk” is subject to interpretation based on warning signals considering, that residents who do not know the warning signals, and know these but cannot cope with such emergent situations. Thus, the authors suppose that assistance with evacuation becomes integral. The questionnaire clarified that most residents had evacuated after the occurrence of the disasters and about 40 percent of the residents had evacuated during heavy rainfall. Therefore, many residents evacuated before the critical situation to be vulnerable to human body, and arranged accommodation and refuge prior to the occurrence of such a disaster. In addition, there are residents who want to evacuate, but cannot for a variety of reasons. This particular disaster has provided several lessons regarding what important measures need to be addressed in response to water induced disasters. Some critical components elucidated upon included safe passages and transportation arteries, safe refuge for citizens, a functional information network, and the indispensability of collectivity within a community located in an isolated mountainous area. The role of public office, which provides disaster-information to local areas, is crucially important particularly in rural mountainous villages where many old inhabitants live.