Based On SWMM Research Of Planning And Construction Of Sponge City

Belong to with the rapid urbanization,the urban area has continued to expand.Meanwhile,as urban greening has not kept pace with the urban development,the proportion of urban surface impervious to the ground and the urban heat island effect has increased.As a result,heavy rainstorms occur frequently in city,and the surface runoff increases as the ground permeability decreases.In addition,due to the old urban drainage network,floods frequently occur in cities,resulting in serious water pollution and degraded water quality.Therefore,urban flooding and water quality problems will not only bring major economic losses to the city,but also seriously restrict economic development.Sponge city is an important theory of urban storm water management.The elastic flow of urban rainwater can be ensured through the methods of storage,interception,infiltration and others,which can control the urban surface runoff,filter the polluted rainwater and rainwater seepage recycling.Through these methods,we could relieve the pressure brought about by urban rainwater problems,and to realize green ecological city construction.In this paper,we analyzed the research progress of sponge cities at home and abroad.By taking the Zhangjiang New District of Ganzhou as an example,we set up its sub-catchment through the boundary of drainage and catchment,which determined by the collected information of its topographic gradients,meteorological hydrology,soil geology,and drainage.Thus,we use the storm water management model(SWMM)to set up the field rainwater flood model in Zhangjiang New District.By using the model,we analyze the effects of its stormwater management under the three kinds of rain conditions of ten,twenty and fifty years once.Comparing the verified results of on-site rainwater flooding with those of the Sponge City Construction Guideline,we conducted low-impact development and transformation of subwatersheds that did not meet the standards.According to the actual situation,we increase the types and quantity of cavernous bodies in each restored area,and then verify it under the design standards of flood prevention in Ganzhou.The results show,rebuilding the sponge city was better in the rainy season where the rainstorm was recurring and weaker in the lager return period of the rainstorm in which the surface sponge became soaked.