Water Pollution Characteristics and Assessment of Lower Reaches in Haihe River Basin

21 water samples were collected from the lower reaches in Haihe River Basin and the pollutant content was detected in May, 2009. The water quality of 11 rivers in this area was assessed with the methods of Single Factor Assessment Method, Comprehensive Pollution Index Method, Fuzzy Comprehensive Evaluation Method and Water Quality Identification Index Method. The results showed that Water Quality Identification Index Method is suitable for water quality assessment of the lower reaches in Haihe River Basin; Single-factor Water Quality Identification Index Method showed that the main pollutants were total nitrogen, ammonia nitrogen, COD, BOD5, permanganate index, fluoride; the pollution belonged to organic and abundant nutrition pollution. Water pollution of all assessed rivers was serious, and inferior class V rivers accounted for 81.8%. The water quality of Qingjinghuang Drain (8.972), Yongding New River (9.654), Ziya New River (10.877), North Drainage River (11.094), Beitang Drainage River (11.376), and the Dagu Drainage River (14.388) was inferior class V and malodorous black, and the pollution level increased orderly. The pollution of rivers in the south of Haihe River was more serious than that in the north. (C) 2010 Published by Elsevier Ltd.