基于LID措施的山地城市雨洪管理模型研究

Study on Storm Water Management Model in Mountain Cities based on LID Practices

为解决山地城市化进程中的水生态问题,以重庆市渝北区江北嘴区域为例,依据现有的城市规划建立SWMM雨洪控制模型,介绍了SWMM模型中的低影响开发(LID)模块。运用SWMM模型在设计重现期分别为1 a、3 a、5 a、10 a、20 a的不同雨情下,模拟分析出LID设施实施前后研究区域的雨水总排放量情况、排水管流量及降雨径流变化。结果表明,LID设施可以削减降雨径流、推迟径流量峰值时刻、缓解排水管网压力,研究区域LID设施控制指标设计取值为绿色屋顶17%、道路透水铺装49%、广场透水铺装41%、植草沟2%、下凹式绿地3%时,可达到80%径流控制率目标。

In order to solve the problem of water environment in the process of mountain urbanization,taking Yubei District of Chongqing as an example,the SWMM model was established based on the existing urban planning,and the low impact development（ LID） module in SWMM model was introduced in this paper. SWMM model was used under different rainfall conditions with the design return period of 1 a,3 a,5 a,10 a,20 a respectively to carry out the simulation analysis on the total rainfall emissions,drainage pipe flow and rainfall runoff change in the study area before and after the implementation of the LID facilities. Results indicated that the LID practices could reduce rainfall runoff,delay the peak moment,and alleviate the pressure of the drainage pipe network. The control index design values of the LID facilities in the study area were 17% for green roofs,49% for permeable pavement,41% for square permeable pavement,2% for grassed swales,and 3% for recessed greenbelt,which could achieve the runoff control target of 80%.