2019 Volume 25 Pages 43-48
In large-scale floods, small and medium rivers and sewers overflow before flooding of large rivers. The evacuation route of the residents might be underwater by the early overflow from small and medium rivers and sewers. In this study, inner and river water simultaneous inundation analysis model considering sewerage system is utileized. The characteristic of risk change in large scale flood is clarified by analyzing the flood risk spatiotemporally. It is revealed that flooding risk such as difficulty in evacuation by walking on the road around the shelter can happnen due to flooding from small and medium rivers. We proposed soft measures such as evacuation plan considering early flood before the large-scale floods.
