北方城市典型内涝积水问题的系统化解决方案

以我国北方某城市的典型易涝区域整治项目为例,介绍了系统化方案的编制方法和实施效果。首先从汇水分区的尺度分析内涝积水成因,然后根据目标要求制定汇水分区优化、源头减排系统改造、排水管渠系统改造、排涝除险系统建设相结合的系统化方案,并建立排水模型对方案实施效果进行量化评估。在案例项目中,通过局部排水管线调整将汇水分区范围减少约24%;通过小区和道路海绵化改造,实现了年径流总量控制率不小于70%、年SS削减率不小于60%的目标要求,同时显著降低了径流峰值;通过雨水管渠提标改造将管渠排放标准提高到2年一遇;通过在人行道设置多处超标径流入河(绿地)通道,提高了排涝能力和调蓄能力,达到了30年一遇内涝防治标准。该系统化方案通过雨水径流的合理组织和排水防涝设施系统改造建设,在消除城市内涝问题的同时,实现了径流总量控制、径流污染控制、景观提升和地下水涵养等多重目标,可为其他城市提供参考和借鉴。

Systematic Solution to Typical Waterlogging Problems in Northern Cities

The preparation method and implementation effect of a systematic plan of a typical waterlogging area remediation project of a northern city in China were introduced.The causes of waterlogging from the scale of the catchment zone were firstly analyzed.Then,a systematic plan combining the optimization of water catchment zoning,the reconstruction of the source emission reduction system,the reconstruction of the drainage pipe and canal system,and the construction of the drainage system were formulated according to the objectives and requirements, and a drainage model was established to quantitatively evaluate the implementation effect of the plan.In the case project,the catchment area was reduced by about 24% through local drainage pipeline adjustment.The target requirements of annual total runoff control rate of no less than 70% and annual SS reduction rate of no less than 60% were achieved through the sponge transformation of residential quarters and roads,and the runoff peak value was significantly reduced.The drainage standard of pipe and channel was raised to2-year return period through the improvement of rainwater pipe and channel.The drainage capacity and storage capacity were improved by setting channels where excessive runoff flowed into the river( greenbelt) in many places along the sidewalk,and the waterlogging prevention reached 30-year return period standard.Through the reasonable organization of runoff and the reconstruction of drainage and waterlogging prevention facilities, this systematic plan not only eliminated the urban waterlogging problem,but also achieved multiple goals such as total runoff control,runoff pollution control,landscape improvement and groundwater conservation,which could provide reference to other cities.