EXAMINATION OF EFFECTIVE PLACEMENT OF EVACUATION SITE AND EVACUATION STARTTIME IN CONSIDERATION OF FLOODING FROM INLAND WATER AND RIVER WATER

Abstract

 Several levees of the Oda River and three tributaries broke down in Mabi-cho, Kurashiki City due to the heavy rain in western Japan in July 2018, and the number of casualties due to inundation reached 54. The subsequent heavy rain caused by Typhoon No. 19 in 2019 and the floods caused by the heavy rain in July 2020 also flooded many rivers and caused many casualties. In order to reduce casualties in the event of such a large-scale flood, selecting an appropriate evacuation route based on the temporal changes in inundation depth and flow velocity due to flooding from inland waters and flooding from rivers, and early evacuation actions is important. In this study, the optimum evacuation routes were examined using numerical results of inland water inundation due to rainfall and inundation due to bank collapse in Mabicho, Kurashiki City, and evacuation sites and start time for safe evacuation were also examined. As a result, the necessity of adding an evacuation site and the safe evacuation start time were clarified.