关键词: 雨洪调控;情景模拟;低影响开发;SWMM模型;GIS;海绵城市;镇江市;

Abstract: To solve urban waterlogging after rainstorm and understand the effect of low impact development (LID) measures on urban stormwater control infrastructure, the downtown of Zhenjiang City, which frequently suffers from waterlogging in recent years, was selected as the study area. The SWMM model was used to construct a drainage system model for the area, and the model simulated the operation of the pipe network system under a 30-year heavy rain that met the local flood control standards. And then taking the heavily submerged catchment area as the research object, 4 LID measures and their different combinations were used to simulate the runoff control situation under 8 scenarios. Finally, 20%, 50%, and 80% green roof (GR) facilities were randomly arranged on the roof of buildings that were extracted by remote sensing, and the response of the runoff coefficient of the catchment area to different proportions of LID measures was compared. The results showed that: ① More than half of the nodes and pipe networks were overflowed and overloaded under a 30-year heavy rain scenario. ② LID measures showed a good effect on the control of urban rainwater. Taking S424 catchment area as an example, in terms of runoff control, Permeable Pavement>LID Combination>Green Roof>Rain Garden. In terms of peak flow reduction rate, Permeable Pavement and Rain Garden were more effective. ③ With the increase of proportion of LID measures, the effect of runoff control was getting better and better. When 80% of the green roofs were randomly arranged in the area, the average runoff coefficient Ψ of the catchment area was reduced by 60.39%. The LID design scheme has obvious effects on the rain and flood regulation in sponge cities, and can provide a reference for local waterlogging management.

Key words: stormwater regulation; scenarios simulation; low impact development (LID)；SWMM model; GIS; sponge city; Zhenjiang City