2017 Volume 23 Pages 161-166
The most utilized flood runoff model for engineering applications in Japan is based on the storage- discharge function of the type S=kQp. The parameters p and k vary between flood events, causing difficulty in estimating and forecasting the flood runoff hydrographs accurately. The aim of this study is to identify the parameters in the storage-discharge relationship for floods for the Sameura Dam basin, Sagae Dam basin, Taisetsu Dam basin and the Iwaonai Dam basin, located in different regions in Japan and representing different topographical, geological and climatological conditions. In order to optimize the parameters p and k by maximizing the Nash-Sutcliffe efficiency, 10,000 simulations are carried out for each flood event by changing the values of k and p. The results show that the optimum parameters in the storage-discharge function, the sets of p and k, for floods in each study basin are represented by the p- k curve on the log-log graph.
