平成27年9月関東・東北豪雨における鬼怒川上山川地区堤防と地下水動態について

抄録

Based on the Kanto-Tohoku heavy rainfall, the foundation leakage occurred in the Kinugawa levee. Since the groundwater supply from the landside of the levee was presumed to be one factor of the leakage, we attempted to investigate causes of the leakage. We measured pore pressures of the levee foundation and comprehensively analyzed data such as rainfall, river water level, construction history and so on. The observed water levels within the levee suggested the effects of groundwater supply from the landside and existence of waters was recognized. A future survey plan was proposed for understanding of the three-dimensional geological structures and making countermeasures.