The study of urban rainstorm waterlogging scenario simulation based on GIS and SWMM model — Take the example of Kunming Dongfeng East Road catchment area

In order to guide the city's waterlogging control, it's very necessary to research the urban waterlogging occurrence rules and how urbanization affects the urban waterlogging. In this paper, we select the catchment area located in Kunming Dongfeng East Road as study area to construct the urban waterlogging simulation model based on GIS and SWMM model. The procedure of model building contains sub-basin division, drainage system generalization, and parameter settings. Then different urbanization degrees and different rainfall return period settings will be tested on the constructed model. The results show that the model can be used for dynamically simulating urban waterlogging. Both runoff volume and peak flow increased significantly with increasing return period. In addition, with the development of urbanization, urban impervious area increased rapidly, but decreased in rainfall infiltration, while the risk of floods increased. This impact was more obvious in the short return period rainfall conditions.