Due to the demand of navigation, flood protection, water supply, etc., modeling of the hydrodynamic and mophodynamic processes in estuaries has been emphasized in last decades. However, this modeling task is extremely difficult, because many very complicated phenomena are involved there, such as the river flow, tidal flow and wave-induced currents as well as the cohesive sediment transport affected by salinity and flocculation. The FVM-based CCHE2D model has been developed to simulate the tidal flow, salinity and cohesive sediment transport in river estuaries. The flow model is very stable and efficient. Large time steps, such as 30 minutes, have been successfully used in the simulation of semi-diurnal tidal flow. The deposition, erosion and transport of cohesive sediment are calculated, taking into account the influence of flocculation and salinity. The model has been tested in Gironde Estuary, France. The simulated water elevation, flow velocity, salinity concentration and sediment concentration are in good agreement with the measured data.
