Abstract:

The imperviable areas have increased as a result of the development 〖JP2〗of urbanization,which usually〖JP〗 causes the significant changes in regional hydrologic〖JP2〗al processes.The longterm hydrological and meteorological〖JP〗 series are typical in the Xitiaoxi watershed of Taihu basin.Anji experimental district,located in the Xitiaoxi watershed,has been set up to investigate the characteristics and laws of rainfallrunoff processes of small urban districts in the eastern part of China.The flows of control sections were observed and calculated in the flood seasons since 2005.Based on the analysis of rainfall, water stage and other underlying data,Storm Water Management Model was applied to simulate several selected typical rainfallrunoff events in the district,and the laws of stormrunoff processes were analyzed.The results indicate that Storm Water Management Model was highly effective and the errors were small,so it could be used to simulate the rainfallrunoff processes and analyze the laws of stormrunoff processes in this area.The results included the decreased lag times,the increased storm flow volumes and the increased peak flows.The peak shape coefficients increased with an average value of 305,which had greatly increased the pressure on flood prevention work.The result should be helpful to study the effects of watershed urbanization on rainfallrunoff processes,city flood prevention,city planning,city management,and so on