title: [Research on the reasons of red water in a southern city in China].
abstract: The red water in the drinking distribution systems of a southern city was investigated by analysing the water quality, such as DO, residual chlorine, iron, manganese, iron bacteria and ammonia-oxidizing bacteria. The objectives of this study were to identify the reasons of red water with the aim to supply the answer to this problem. The results showed that the main compositions of the deposits were iron and manganese. There were manganese overstep (the maximum of Mn could reach to 0.33 mg x L(-1)) in the plant effluent with Larson ratios > 1 and the significant difference in water quantity, sulfate and electrical conductivity among the four plants. The density of the iron bacteria and ammonia-oxidizing bacteria (10(0)-10(3) MPN x mL(-1)) was high. The potential reason for the red water was the water corrosion of plant effluent. Secondly, the red water easily occurred in the distribution systems with lower DO and residual chlorine. In addition, serious nitrification caused microbiological corrosion was another vital reason. According to the research, the primary methods for controlling red water were proposed.
authors.affiliation: Institute of Architectural Engineering, Beijing University of Technology, Beijing 100124, China. zhaolele_2008@126.com
authors.forename: Le-Le
authors.initials: LL
authors.lastname: Zhao
authors.forename: Xing
authors.initials: X
authors.lastname: Li
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.forename: Wei-Xiong
authors.initials: WX
authors.lastname: Chen
mesh_terms: D002681:China; D002947:Cities; D007501:Iron / Q000032:analysis; D008345:Manganese / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014876:Water Pollution / Q000517:prevention & control*; D014881:Water Supply / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D008345:Manganese; D007501:Iron