The dam site of the proposed Dazhaimen Reservoir is located in the middle reaches of Hecheng River, a tributary on the left bank of Jinsha River. The dam site controls the watershed area 1 108km2, and the average annual runoff is 551000000 m3. The river bottom elevation at the dam site is about 1500m, the planned dam height is 120m, and the total storage capacity is 654.38+500 million m3. It is a large-scale (2) water conservancy project mainly based on irrigation. The main construction contents include new reservoir hub, back dam power station, photovoltaic irrigation station, trunk and branch water conveyance channels, etc. The cultivated land in the irrigation area is mainly distributed at the altitude of 1700 ~ 1900 m, and the control range of gravity irrigation of Dazhaimen Reservoir is about150,000 mu, and the rest is planned to be irrigated with water, and the irrigation water lifting range is 100 ~ 300 m, which will solve the problems of Zhang Guan Town, Luchang Town, Guanhe Town and Li Xi City in Huili City. There are about 700,000 mu of cultivated land and gardens in villages and towns in the irrigation area, with a population of 220,000. The total investment of the project is estimated to be 3 billion yuan. Dazhaimen Reservoir Project has been included in the "14th Five-Year Plan" of water security in Sichuan Province and the high-quality development plan of Anning River Basin (2022-2030).