抄録
It is important to establish an evaluation method for probability of levee failures during large scale floods for planning adaptation measures for a whole river basin. In this study, the evaluation method for probability of levee failures are presented. This method consists of the flood flow analysis and reliability analysis based on soil modulus investigated by longitudinal boring surveys on the levee. The present method was applied for the lower Shinanogawa River and the probability of levee failures were evaluated for large scale floods whose water levels reached the freeboard of levees. Finally we discuss issues to be solved and future works toward the crisis management plan for large scale flood.