There are more than 300 islands in the upstream reservoir, with a total length of 380 meters, a dam height of 28 meters, a top width of 9 meters, a catchment area of 140 square kilometers and a water area of more than 20,000 mu. The lake is open and calm, and it is the first-class clean water in the country. It is a large-scale reservoir mainly for irrigation, with comprehensive utilization of flood control, aquaculture, power generation and tourism. It is a typical alpine Pinghu, which was built in 1958 and 1960. It was one of the 60 large reservoirs in China at that time, and the word "upstream" was the product of the red slogan "Go all out and strive for the upstream".