Analysis of Runoff Changes of Niqu River in Water Diversion Area of Western Route Project of South-North Water Transfer Project

The runoff data of Zhuba Station at Niqu river in water diversion area of Western Route Project (WRP) of South-North Water Transfers Project (SNWTP) from 1961 to 2010 were applied to estimate the coefficients of variation of hydrology, the peak pattern degree, and ample flow VS low flow, climate tendency rate and so on. The results were used to analyse the effects of hydrological regime on river discharge in the water supply area of the first stage project in WRP. The results demonstrated that: The annual river discharge is increasing in Niqu River which is the water supply area in the first stage project of WRP. The cumulative increased river discharge is 0.52×10⁸m³ within 50 years which is 2.6% larger than the average value. The runoff increased each year in non-flood season and decreased each year in flood season.