2011 Volume 17 Pages 233-238
Gravel-bed rivers in Japan are now facing a multitude of problems relating to fluvial environment and flood control. These problems include the growth of riparian trees on riverbeds and the high-speed water flow in a low-flow channel, which became pronounced due to increasing channel degradation and cross-sectional elevation change that are triggered by the change in external factors. This study aims to propose effective measures for reproducing gravel bars by leading flood flow over vegetated bars. In this study, we have analyzed the effects of disturbance caused by flood channel excavation by evaluating changes of bed material and form of the flood channel using two dimensional analysis of river bed variation. The aquatic environmental impact caused by the excavation of the flood channel was also evaluated quantitatively using the Physical Habitat Simulation Model (PHABSIM) for fish habitat. Furthermore, we studied its application to other rivers by comparing river characteristics and hydraulic analysis results.
