流域尺度视角下海绵城市建设途径及区域径流控制

随着城市化的快速发展,城市不透水区域面积逐年增加,导致城市洪涝风险加剧、径流污染负荷增加等突出雨水问题,也给流域的水安全及水环境带来严重影响.针对上述问题,近年来基于流域管理的城市雨水管理模式得到快速发展.通过流域尺度城市单元土地开发前后峰值流量和雨水径流污染负荷变化的分析,提出以受纳水体过流能力和水环境自净容量为约束条件的流域尺度海绵城市建设管控方法,建立基于水量、水质总量控制为主要目标的多层级雨水径流控制方法,构建流域-城市尺度的场地可持续开发雨水管理模式,并以某开发区为例,分析区域径流总量控制、径流峰值削减及径流污染控制等目标的实施途径,以期为未来流域管理和海绵城市建设的统筹协调提供支撑.

Approaches and strategies of sponge city development based on watershed management

With the development of urbanization, the urban impervious area has increased rapidly, leading to serious rainwater problems such as the increased risk of urban flooding and runoff pollution. Meanwhile, there has also been severe impact on water safety and water environment at watershed scale. Therefore, the urban stormwater management model based on watershed management has developed rapidly in recent years. By analyzing the changes in the peak flow rate and the pollution load of the stormwater runoff before and after the development of the urban land, a management and control method for sponge city construction was put forward at basin scale, which was constrained by the peak flow rate of the flooding way and the self-purification capacity of the water environment. A multi-level stormwater control approach was put forward based on water quantity and quality control, and the stormwater management model of land sustainable development was proposed at the watershed-urban scale. Taking a development area as an example, the construction approaches of regional total runoff volume control, peak flow rate reduction, and runoff pollution control were analyzed, aiming at providing support for the overall coordination of watershed management and sponge city construction in the future.