基于SWMM模型与低影响开发模式的滨水地区内涝防控方案——以厦门市杏林湾选区为例

Waterlogging Prevention and Control Scheme in Waterfront Area Based on SWMM Model—A Case Study of Xinglin Bay in Xiamen

在快速城镇化进程中,由于硬质下垫面面积比例增加,导致城市内涝问题日益突出。选取厦门市杏林湾地区作为研究对象,以绿色经济与低影响开发为目标,运用SWMM技术构建降雨-径流模型,分别对低影响开发前后的地块进行暴雨重现期2年一遇和5年一遇情景的模拟,确定地块内涝易发区域积水节点,根据节点位置布设低影响开发(LID)措施,以此提高研究区对内涝灾害的承受能力。情景模拟结果为:杏林湾选区在重现期2年一遇时,地块东部海湾口处容易出现内涝现象;重现期5年一遇降雨导致杏林湾选区排水系统出现大范围节点溢流,主要集中在湾区滨水空间及海湾口处。通过对易涝区增设LID措施降低径流总量、削减洪峰小时流量,从而使年径流控制率提升至77.5%,降低城市内涝灾害风险。

In the process of rapid urbanization,the urban waterlogging problem becomes increasingly prominent because the ratio of hard underlying surface area increases.Taking the Xinglin Bay block in Xiamen as an example,the rainfall-runoff model was constructed by using the SWMM technology based on the principle of green economy and low-impact development.The rainstorm recurrence period for P=2a and P=5a conditions were simulated for the plots before and after the low-impact development.It determined the nodes of the rain-prone areas through the current rainfall simulation.LID measures were deployed to alleviate surface runoff according to the location of the rain-prone areas.The bay mouth of the eastern part of Xinglin Bay are prone to waterlogging in the Xinglin Bay district during the two-year recurrence period.The rainfall occurs every five years in the recurrence period which leads to the overflow of the drainage system for Xinglin Bay which mainly concentrated in the waterfront space and the bay mouth.By establishing LID measurements,the rate of annual runoff control in the new area is increased to 77.5%,which is accompanied by the reduction of the total runoff,the peak hourly discharge,the rainstorm runoff coefficient and the risk of urban rainstorm and waterlogging.