超過洪水時のダム洪水調節操作手法に関する一考察 -平成30年7月豪雨災害を踏まえて-

Abstract

In July in 2018, a strong frontal rain system caused prolonged and torrential rainfall in the broad areas in the western Japan. While many reservoirs contributed to mitigate flood impacts by controlling flood water in the rivers, some reservoirs lost their flood control volumes to regulate river flow in the downstream by the overwhelming amount of inflow in the middle of the flood event. Those reservoirs therefore had to release the same amount of water as inflow after that, and resulted in severe inundation in the downstream in some river basins. Considering lessons learnt from this flood event, a robust reservoir operation method is proposed for flood control under extreme flood events in this paper.