Embraced by green mountains, Changkeng is a branch of Beitai River in Wuguishan Town, where one excavator continues excavating along the hillside to build up a new reservoir. The bottom of Changkeng has been poured with concrete as the basis of the first layer. The reconstruction of the three-level reservoir has been started since January 7, 2010 in Wuguishan, and is expected to be completed before the end of this year.

The reservoir's catchments area is 5.17 square kilometers, and the capacity of it will reach 300 million cubic meters, which will far more exceed the he old one of 1.31 million cubic meters and less than the half of the theoretical capacity. The reconstruction will be 2 meters higher, and 30 million cubic meters larger in reservoir capacity. It is estimated that the total capacity will be up to 1,613,200 cubic meters and provide enough water for Wuguishan area after reconstruction. Since no human or animals living there, the upstream of the reservoir is totally free from pollution. The reservoir water is completely pure and ecological. People in Wuguishan will drink the most natural pure water.