Hunan Town Reservoir

The Hunan Town Reservoir is located within the territory of Quzhou, Zhejiang, on the Wu River, a tributary of the Qiantang River's tributary Qu River. It is a primary hydroelectric station in the cascading development of the Wu River, 29 kilometers away from the secondary station (Huangtankou Reservoir). The catchment area above the dam site is 2,151 square kilometers, the river channel is 116 kilometers long, the average annual rainfall in the basin is 1,770 millimeters, and the average annual flow is 83m3/s. The Hunan Town Reservoir hub consists of a concrete trapezoidal support pier dam, a 5-hole dam crest spillway, a 4-hole mid-hole flood discharge tunnel, a power generation and water conveyance tunnel, and a diversion-type power station. The dam is 129 meters high, with a crest elevation of 242 meters and a length of 440 meters. It is designed for a 0.1% frequency flood and checked for a 0.01% frequency flood. The total reservoir capacity is 20.67 billion cubic meters (corresponding water level 240.25m), the normal storage capacity is 15.82 billion cubic meters (normal water level 230m), and the dead storage capacity is 4.48 billion cubic meters (dead water level 190.0m), with a flood control capacity of 5.5 billion cubic meters set up in a full over-height manner. The flood control capacity enhancement project of Hunan Town Reservoir plans to adjust the flood limit water level from 228 meters to 230 meters, restoring the reservoir's design function. At the same time, the standard for reservoir land acquisition will be raised from a flood that occurs once every two years to one that occurs once every five years, and the standard for reservoir resettlement will be adjusted from a flood that occurs once every ten years to one that occurs once every twenty years. In addition, land acquisition and resettlement policies and flood control road construction in the reservoir area will be carried out. After the implementation of the project, the following socio-economic benefits will be generated. Effectively enhance the flood control capacity of the basin. The preliminary implementation plan increases the existing flood control capacity by 0.42 billion cubic meters, allowing for the retention or staggered release of 2000 m3/s flow for 5.8 hours; retention or staggered release of 5000 cubic meters per second flow for 2.3 hours; retention or staggered release of 10000 cubic meters per second flow for 1.1 hours; effectively alleviating the flood control pressure in Hangzhou, Jinhua, Quzhou, and other places within the Qiantang River basin, and overall enhancing the flood control capacity of the basin.