Evaluating low impact development of Urban rainwater management at the watershed scale

Rapid urbanization has led to ecological problems such as urban stormwater disasters and water pollution, and Low Impact Development (LID) has been proven to be an effective urban stormwater management technique. This study simulated the regulation of runoff volume and pollutants by means of LID stormwater control measures using the Stormwater Management Model (SWMM) in the Sanba River Watershed of Xuzhou City. The results show that after setting up LID measures according to the requirements of sponge city construction in Jiangsu Province and Xuzhou City, surface runoff from the watershed can be adjusted to decrease by about 75% while both infiltration and final storage increase. LID also has a good effect on water purification, with reduction rates of TP and TN of about 35% and 32%, respectively. This study can provide technical support for improving urban rainwater management, deepening the resource utilization of urban rainwater, and building a livable-landscape-ecological city.