基于暴雨径流管理模型(SWMM)的海绵城市低影响开发措施控制效果模拟

为解决城市化过程中遇到的水生态、水安全和水环境问题,以低影响开发(LID)为核心理念,我国提出了海绵城市这一新型城市雨洪管理概念.本研究利用芝加哥雨型和沈阳暴雨强度公式构建了不同重现期的降雨过程线,然后利用暴雨径流管理模型(SWMM)模拟分析了城市化前、城市化后和LID措施后3种情景方案的水文水质过程.结果表明: 随着降雨重现期的增大,LID措施减少的径流量逐渐增大,研究区径流量基本达到城市化前的水平.LID措施对总悬浮颗粒物(TSS)、化学需氧量(COD)的去除量较大,但TSS和COD排放量仍然远远高于城市化前,总氮(TN)和总磷(TP)的污染物排放量接近于城市化前的自然状态.随着雨强的增大,径流流速增大,LID措施消减的TSS、TP和COD量逐渐减小.

Simulation on the control effect of low impact development measures of sponge city based on storm water management model (SWMM)

In order to solve the problems of water ecology, water security and water environment in the process of urbanization, sponge city, the new urban storm water management concept, was put forward based on the low impact development (LID). The Chicago rain type formula and Shenyang rainfall intensity formula were used to form Shenyang rainfall process line of different return periods. The water quantity and quality processes of the three scenarios, before urbanization, after urbanization and after setting LID measures, were simulated and analyzed by storm water management model (SWMM). The results showed that with the increase of rainfall return period, the reduced runoff volume of LID measures was gradually increased, and the runoff volume was close to that before urbanization. LID measures removed lots of TSS and COD, but their emissions were still higher than that before urbanization, while that of TN and TP were close to that before urbanization. With the increase of the rainfall intensity, the runoff velocity increased, but the removal of TSS, TP and COD by LID measures decreased gradually.