Water Supply Risk And Reliability Analysis Of The West Route Of South-to-North Water Transfer Project In The Yalong River Basin Diversion Junction

The South North Water Transfer West Route Project is a tranbasin water diversion project, transferring water from the main stream and tributaries of the upper Yangtze River to the upstream of the Yellow River, it is an important strategic measure of complementing the water head shortage in Yellow River and solve the problem of water shortage and drought in Northwest china, the fact of if we can transfer water according to the plan is directly associated with the economic and social development in west region,and with the strategic deployment of western development. Therefore,it is essential to evaluate the risk degree ,on the basis of which we get rational risk control and regulation measures. It is obvious the research result is of great significance.The paper analyzed the water supply risk and reliability of the first stage construction of the South North Water Transfer West Route Project in Yalong river basin water diversion area ,the main research contents and conclusion analysis are as follows:(1)To estimate water supply precisely, it is more reasonable to simulate based on measured data,rather than use historic runoff series. The paper adopted autoregressive model of AR(1) to simulate annual runoff series , adopted autoregressive model of AR(2) to simulate annual runoff series for Aan diversion junction, adopted seasonal autoregressive model of AR(1) to simulate Monthly Runoff Series for Aan and Renda diversion junction. The simulation of runoff series can keep up very well with the statistical characteristics of original series.(2)The paper presented the concept, theory and calculation method of risk analysis, stressing on the risk of supply. To measure supply risk, it set up reliability index, supply destroying depth index and recoverability index. In the mean time it built the mix programming model, which adding three supplying index to the model on the base of linear programming for reservoir design and operation analysis.(3)Using model above to evaluate risk in the Yalong diversion junction, first of all, it should analyze the influential factors to get natural runoff which is the most important factor as well as an uncertain factor affecting transferable water amount. Other influential factors included industrial and agricultural water demand on upstream of the dam, water discharge and the loss in the reservoirs. Using measured data of monthly runoff and simulation of monthly runoff in the model, it was concluded that the water supply can be guaranteed in Aan and Renda diversion junction.