Modeling sediment transport and fluvial processes in the Yangtze River reach between the Three Gorges Dam and the Gezhouba Dam

This paper presents a numerical simulation of sediment transport and bed scour / sedimentation process in the Yangtze River reach between the Three Gorges Dam and the Gezhouba Dam (i.e., the Gezhouba Reservoir). A one-dimensional model was developed to simulate water flow, bed load transport and non-equilibrium suspended sediment transport, by solving the St. Venant equation with a characteristic method, and the non-equilibrium sediment transport processes with a difference scheme. The impact of changes in particle size of discharged sediments from the Three Gorges Reservoir after its impoundment was considered, and variations in size distribution of bed material in the Gezhouba Reservoir was simulated and verified based on field observations during the 1998 flood. Result of the simulation model can be used to predict fluvial processes further downstream of the Gezhouba Dam.