短時間降雨情報に基づく中小河川の洪水氾濫危険度予測法の提案と新潟県中小河川への適用

抄録

In small rivers, it is difficult for the river manager to issue a proper evacuation order as the water level data are not available in some rivers and runoff is faster compared with large rivers. In this study, the integrated river basin model which consists of a run-off model based on the kinematic wave model and a two-dimensional inundation model based on the pond model is applied to one of small rivers in Niigata, Japan. The past inundation in July 2004 is well simulated by this model. Next, imposing various patterns of rainfall distribution with two and three hourʼs durations, inundations have been simulated and their extents have been examined by the above model. As a result, we obtain the diagram which can express the inundation level by the rainfall characteristics. This diagram may be useful for considering flood disaster reduction in a small river basin.