Possibilities of neighborhood evacuation within a district in the event of a large-scale flood in a low-lying area: A case study of Shinden district in Tokyo

摘要

The objective of this study is to examine the possibilities of neighborhood evacuation within a district in the event of a large-scale flood in a low-lying area, through a case study of Shinden district in Tokyo. Shinden district is highly vulnerable to flooding because it is surrounded by two large rivers, namely, the Arakawa River and Sumida River. In a part of the district, however, there is a large-scale super levee area that is apparently used as a safe evacuation area. In conclusion, in the event that the Arakawa River in Shinden district is breached, the number of estimated potential evacuees at night exceeds the number of estimated night-time evacuees, and the number of estimated potential evacuees in the daytime exceeds the number of estimated daytime evacuees. Therefore, it is possible for people in an inundated area to evacuate to safe places in the neighborhood on the condition that an appropriate evacuation system is established, taking into consideration possible routes to the evacuation areas and the possibility of making use of private apartments or other private buildings as evacuation spaces. In particular, the super levee project has contributed to the creation of a large-scale neighborhood evacuation area.