Abstract
A method for establishing stage-discharge rating curve (H-Q curve) in a flood event was discussed, which used a runoff model to the rainfall data and the water level data observed in a basin. A quadratic function that represented the H-Q relation in the river channel was built into the runoff model. When the observed water level hydrographs during a flood event was reproduced by the model, the H-Q curve was established. The method was applied to four water level stations in Dokigawa River basin, and the established H-Q curve was compared with the H-Q curve based on the runoff observation. The error margin of the established H-Q curve and the observed was about 5% or less. The proposed method can be used to verify and adjust the observed H-Q curve that may lead to an unsatisfied water budget of rainfall and discharge for the basin.
