Abstract:

In this paper, Gray Clustering Method was applied in evaluate the water quality of three tributary rivers (which are Bibei River, Motan River and Heishui River) in Beibei District of Chongqing. The monitoring data came from the five monitoring cross sections, where Yantangkan, Longfeng River outfall, Xixi Bridge, Pianyan and Shuitu County were selected and monitored in February, May and August of 2007, respectively. The evaluative results showed that the differences among the water quality of monitoring cross sections are large, and Longfeng outfall and Xixi Bridge were polluted worse than the others because the emissions of industrial waste water and domestic sewage arbitrarily, with Grade Ⅴwater quality standard in three monitoring data and the water quality level are GradeⅡ or Ⅲ except Longfeng outfall and Xixi Bridge monitoring cross sections.