Demonstration project of water pollution treatment in small watershed: ecological remediation of Changqiao Stream, West Lake, Hangzhou

Abstract

长桥溪是杭州西湖上游四大溪流之一.长桥溪生态修复工程利用长桥溪流域的微地貌和水动力作用,通过地埋式污水处理系统与人工湿地相结合的方法,将污水处理工艺与景观园林紧密结合,综合运用物理、化学、生物等手段对长桥溪流域内污水进行处理,从而减少该溪向西湖的污染物排放.工程经过两年运行,2006年其入湖湖水的TP、TN、NH₄⁺-N和COD_Mn浓度分别降至0.067±0.041mg/L、3.54±1.23 mg/L、0.59±0.46mg/L和2.11±0.38mg/L,较2003年依次降低了88.5%、68.8%、89.1%和68.0%.;Changqiao Stream is one of the four upper streams of West Lake. The ecological remediation of Changqiao Streamcreatively integrated sewage disposal technique and landscape garden. Via underground sewage disposal system and artificialwetland, sewage in catchment of Changqiao Stream was disposed physically, chemically and biologically, so as to reduce thepollutant discharge into West Lake. After two years running, the concentration of TP, TN, NH₄⁺-N and COD_Mn were reduced to 0.067±0.041mg/L, 3.54±1.23 mg/L, 0.59±0.46 mg/L and 2.11±0.38 mg/L respectively in 2006, decreasing by 88.5%、 68.8%、 89.1% and 68.0% compared with 2003..