Study on Calculation Method of Water Resources Supply and Demand Balance in Plain River Network Area

Abstract

After the impoundment of the Three Gorges reservoir, the middle and lower reaches of Yangtze River will have a long distance erosion in a long time, and in the conditions of the same flow, the water level of the three outlets along Jingjiang river reach (Songzi outlet, Taiping outlet, Ouchi outlet) will drop, which leads to the flow diversion reduction of three outlets. Undoubtedly, all these will have an impact on irrigation and water supply of river networks on south bank of Jingjiang river reach. The calculation of water resources supply and demand balance is the foundation of analyzing the influence of the Three Gorges Project on the river networks on south bank of Jingjiang river reach, clearing the key link of water shortage and allocating water resources. The calculation of water resources supply and demand balance in this area, however, has unique complexity of plain river network, which is caused by multi-water sources and multi-water intakes. To handle this problem, the water resources supply and demand balance model in plain water network with multi-water sources and multi-water intakes is established, which is based on the characteristics of plain river network. And this model is utilized to calculate and analyze the water resources supply and demand balance in river networks on south bank of Jingjiang river reach. Relevant research results provide new methods and thoughts for the calculation and analysis of water resources supply and demand balance in plain river network.