Modelling flow in the middle and lower Yangtze River, China

Abstract

A one-dimensional numerical model was developed to simulate the hydrodynamic processes in a large and complex river network located in the middle and lower Yangtze River basin, China. The main stem of the river is connected to two large lakes, Dongting and Poyang, through many branches. A mass conservation method was used to determine the lateral inflows from local basins along the river. The model was verified against measured data at a large number of hydrological stations over a 2-year period. The water levels and discharges predicted by the model were found to generally agree well with the measured data. The model was then used to reproduce the flow process during a large flood event that occurred in 1998. It was found that the two large lakes could store a large volume of water and thus played an important role in attenuating the flood impact.