Nushan Lake

Nushan Lake is located on the right bank of the Huai River, eight kilometers north of Mingguang Town in Jiashan County. It was formed from water accumulating in a local depression of the Tanlu Fault Zone. Due to the rising water level of Hongze Lake, the lake area has gradually expanded. It receives inflows from the Chi River to the south, with a total catchment area of 4,215 square kilometers. The lake area stretches from Moshan to Jiuxian Town (now called Nushanhu Town), merging seamlessly with the Chi River. It extends 40 kilometers from north to south and 1–5 kilometers in width. To the north, it connects via the Nushan Lake Water Control Hub (which includes a regulating sluice, ship lock, and water-lifting station) to Qili Lake, eventually flowing into the Huai River at Hongshantou. In the 1950s, the lake covered a maximum area of 115 square kilometers with a total volume of 510 million cubic meters. The Nushan Lake Water Control Hub was built in 1981. With a lakebed elevation of about 11.0 meters, when the controlled water level is maintained at 12.0 meters, the corresponding lake area is 74 square kilometers with a volume of 43 million cubic meters; at a controlled level of 14.5 meters, the water surface expands to 110.2 square kilometers with a total volume of 247 million cubic meters; the dead water level is set at 12.3 meters, corresponding to a lake area of 87 square kilometers and a volume of 66 million cubic meters. The design capacity for a once-in-a-century flood event reaches a water level of 17.18 meters, with the lake area potentially expanding to 138 square kilometers. The lake water is light greenish-yellow, with transparency of 0.15–0.2 meters, a pH value of 7.9, and mineralization of 243 mg per liter, classifying it as calcium-type bicarbonate water, Group I. The lake is rich in aquatic products, particularly known for whitebait, hairtail, shrimp, crabs, gorgon fruit, and carp. Vessels of up to 100 tons can navigate between the lake and the Huai River. The Mingguang mung beans produced on the lakeside hills are renowned both domestically and internationally.