[Characterizing nutrients of urban stromwater runoff in Zhenjiang].

Urban stormwater pollution is recognized as one of the major causes of water quality deterioration in the receiving water bodies. Starting in May 2006, a study was conducted to characterize water quality from representative land uses types in Zhenjiang. By analyzing the varieties of suspended solids (SS) and nutrients, the results show that the 5-40 microm size class dominates in all the samples, and urban stormwater pollution mainly results from commercial area where concentrations of pollutants are so high that concentration of SS reaches 978 mg/L. Concentrations of pollutants in initial flush are very high, and they descend sharply along with the time to reach the stable stage. The main phases of pollutants discharge are dissolved nitrogens, particle phosphorus and SS. Analysis of correlation of SS and other pollutants finds that SS are the absorbed carrier of nutrients from urban stormwater runoff, and removal of SS is the effective way to control urban stormwater pollution in Zhenjiang.