中小河川を対象とする河川水位予測手法の構成法について

抄録

Development of a real-time flood forecasting method which enables to predict water stage for a small-and-medium-sized. river, in particular for a river section where a rating curve does not exists, is an urgent task to reduce flood disaster damages. In this study, we examine the simulated water stage obtained by a kinematic routing model embedded in our distributed hydrologic model operated at the Yodo River basin. For the flood by the typhoon No. 23 in 2004, the flood marks along the Katsura River is compared with simulated flood stages. It was found that simulated discharge is insensitive to the river routing model parameters (the Manning roughness coefficient and a setting method of channel cross section). However, simulated water stage was quite sensitive to the parameters. Based on the simulation results, a framework of a real-time stage forecasting method for small-and-medium-sized catchment is discussed.