平成30年7月豪雨時のダムの洪水調節操作と今後の課題

Abstract

In the torrential rain disaster in July 2018, heavy rain over a long period occurred in a wide area mainly in western Japan which caused severe flooding in various places. There were many catchment basins greatly contributing to reduce the flood water level in the downstream river by the flood control operation of the dam reservoir. Meanwhile, due to prolonged rainfall, the flood control capacity of the dam is expected to be full, and some dams carried out the emergency spillway gate operation at the time of extreme flooding. In this paper, we outline the implementation status of the dam flood control operation in the heavy rain disaster, analyze the effect and problem, and describe the direction of countermeasures for these problems for large-scale flooding in the future.