Abstract
This study aims to estimate discharge considering river bed evolution during flooding with calculation of hydraulic resistance in the Hime river. The river is a flashy river and has active sediment movement. An observation site of the river has a problem that discharges converted from water level and calculated by hydrological model differ. It is considered that the both have error, and the error of the former is caused by changes of hydraulic resistance and river bed elevation. Hence these changes need to be taken into account to estimate discharge accurately in the river. First, analysis of hydraulic resistance with observed data by equipment such as ADCP is conducted, then river bed elevation and discharge are estimated using the analysis result of hydraulic resistance and hydrological quantities over water surface such as water level and water surface velocity. As a result, discharge calculated with estimated river bed elevation reproduces the one calculated with river bed elevation observed by ADCP, and shows higher values than discharge assuming fixed river bed elevation.
