平原河网城市雨水系统排水能力及内涝风险评估浅析

以苏州市相城区某圩区为例,采用Mike系列模型建立排水防涝系统耦合模型,同时考虑平原河网地区城市排水防涝特征,将恒定均匀流推理公式法、水量平衡法等传统推理公式法与数学模型法相结合,评估多种情景下的雨水系统排水能力、内涝风险。结果表明,研究区域现阶段排水防涝系统主要问题在于管网排水能力不足导致涝水无法排入河道引起地面积水,排水防涝措施应首先提升管网排水能力,同时也要注意适当提升河网蓄泄能力,使市政排水和水利排涝标准相匹配,最大程度地发挥平原河网区二级排水系统的综合效益。

Assessment of Drainage Capacity of Urban Rainwater System and Waterlogging Risk in Plain River Network Area

Taking a Polder Area in Xiangcheng District of Suzhou as an example, the coupling model of drainage and waterlogging control system is established by using Mike series model. Considering the characteristics of urban drainage and waterlogging prevention in plain river network area, the constant traditional reasoning formula method and mathematical model method are combined to give full play to their respective advantages, and the drainage capacity of rainwater system and waterlogging risk assessment under various scenarios are carried out. It is revealed that the main problem of the drainage and waterlogging prevention system in the study area at present is that the insufficient drainage capacity of the pipe network results in the failure of the waterlogged water to be discharged into the river channel. The drainage and waterlogging prevention measures should first improve the drainage capacity of the pipe network. At the same time, it should pay attention to properly improve the storage and drainage capacity of the river network so as to match the municipal drainage and water conservancy drainage standards, which maximizes the comprehensive benefits of the secondary drainage system in the plain river network area.