基于不同排水片区的低影响开发措施优化方案选取

以福建省龙岩市中心城区为例,运用SWMM模型中的LID模块,模拟分析了10%的雨水花园、20%的绿色屋顶、15%的渗透铺装以及一项组合措施(包括3%的雨水花园、7%的绿色屋顶和5%的渗透铺装)对研究区上、中、下游典型排水片区(依次记为A、B、C)的径流总量、洪峰流量及污染物负荷的削减控制效果,包括削减效率及对降水历时的敏感性。通过分配指标权重对各LID措施效果进行综合评价,最终确定各排水片区的LID最佳布设方案。研究结果表明:A片区优选绿色屋顶方案,B片区优选组合措施方案,C片区优选雨水花园方案。

Selection of optimal LID measures based on spatial difference of drainage area

Taking the downtown area of Longyan in Fujian as an example, based on the LID module in SWMM model, this paper simulated 10% of Rain Garden, 20% of Green Roof,15%of Permeable Pavement and a combination measure (including 3% Rainwater garden, 7% green roof and 5% infiltration pavement) to analyze the reduction rate, including the reduction of efficiency and sensitivity to precipitation over time,of the total runoff, peak flow and pollutant load in the upper, middle and lower reaches (denoted as A, B and C) of the central urban area of Longyan City, Fujian Province. The comprehensive evaluation was carried out by introducing the weighting coefficient. Based on the spatial difference of the drainage area, the LID optimal layout scheme of each drainage area is finally determined. The results show that the A area should select the green roof scheme, the B area should select the best combination scheme, and the C area should choose the rainwater garden scheme.