After the Three Gorges Project to use the impact analysis by scouring and silting in Poyang Lake control engineering area

Abstract

Lake control project of Poyang lake is a large scale with a complex operation scheduling, which has an effect on the flood control and environment near the connected area between Poyang lake and Yangtze river. This paper combines one-dimensional and two-dimensional water and sediment mathematical model to calculate and analyze it. The application of a long reach and long term one-dimensional mathematical model from Yichang to Datong provides boundary conditions for the two-dimensional model. Two-dimensional model between part of Yangtze river and Poyang lake is used to calculating the influence caused by lake control project to the bed erosion and deposition between the river and lake after the operation of Three Gorges Reservoir. The research result shows that after a 10-year operation of lake control project, riverbed scouring takes place on a large scale near the connected area as long as the point bar which used to be deposit, and the deepest erosion on bed groove reaches about 1.3m. Sediment scouring takes place on the Yangtze river under the lower Zhangjiazhou channel, but the upper channel changes less relatively.