Hunan Wastewater Treatment Plant, Hengyang, Hunan Province, China

The Hunan wastewater treatment plant is located in Kaiyun Town, Hengshan County, Hengyang City, Hunan Province, China. It serves a population equivalent of 150,000, classifying it as a large agglomeration under Chinese wastewater regulations. The plant is part of the municipal infrastructure for the Hengyang metropolitan area. As a facility serving over 100,000 people, the plant is expected to meet secondary treatment standards under China's Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants (GB 18918-2002). Chinese regulations require such plants to achieve effluent quality suitable for discharge into surface waters, with nutrient removal in sensitive watersheds. The plant's treated effluent ultimately flows into the Xiang River, a major tributary of the Yangtze River. The Xiang River basin supports diverse aquatic ecosystems and provides water for agriculture, industry, and drinking water downstream. Proper treatment at this facility helps protect water quality in the Xiang River and the broader Yangtze River system, which is ecologically and economically vital for central China.

The plant discharges into the Xiang River basin, which drains into Dongting Lake and then the Yangtze River. The Xiang River supports fisheries, irrigation, and municipal water supplies. Downstream ecosystems include wetlands and floodplains that provide habitat for migratory birds and aquatic species. Effective wastewater treatment is critical to prevent eutrophication and maintain water quality in this densely populated and agriculturally active region.