ABSTRACT

The Three Gorges Project (TGP) began to operate since June 2003. Operation of the reservoir alters the hydrological regime of the downstream river and consequently brings significant change in scouring and silting of the river channel. In this study, by use of prototype observational data, the recent variation of the flow and sediment conditions of the Jingjiang River and the change of flow and sediment diversion from the Jingjiang River to the Dongting Lake are analyzed first. Then the scouring of the channel of the Jingjiang River after the TGP operation is examined. Finally the variations of the river regime are summarized. The results of analysis indicate that, the average annual erosion quantity of the Jingjiang River after the project operation is far more than that before. Though the overall river regime of the Jingjing River is comparatively stable, significant adjustment of the river regime occurs locally after the TGP operation.