Modelling of Flood Defence Measures in the Lower Yellow River Using Sobek

This paper describes the application of a one-dimensional model to the Lower Yellow River reach from Tiexie to Gaocun. The model is based on SOBEK, the 1D modelling system of WL vertical bar Delft Hydraulics. In the model the flow, sediment transport and morphological changes are simultaneously simulated using the same time step. This turns to be necessary because of the large sediment transport rate, which makes the morphological time scale of the river very short. The model has been calibrated for a flood period in August 1982, using field data on water level, discharges, sediment concentration and morphological changes. The calibrated model has been applied for evaluating a number of flood defence measures. The flood control measures considered are inspired by the "Room for the River" policy which is now being implemented in The Netherlands. Despite the extreme complexity of the Yellow River and the restricted availability of field data, encouraging results have been achieved in the study, indicating that such a model can be a useful tool for flood management in the Lower Yellow River.