Study of urban storm-flood simulation model based on SWMM:the case study of Niushan watershed of Dongguan City

In order to study the laws of urban storm-flood and the influence of urbanization on storm-flood and guide urban flood control and drainage,the urban storm-flood simulation model for Niushan watershed in Dongguan city was established based on Strom Water Management Model(SWMM) through sub-catchment division,drainage network generalization and parameters setting and debugging and so on.The established model was applied in the simulation in the designed cases of different return periods and urbanization levels.The results show that the established model can be used in whole process of dynamic simulation of urban storm-flood.It is also concluded that with the increment of return period,the total runoff volume and peak flow increase significantly with gradual reduction of amplification;with the development of urbanization,rainfall infiltration decreases,the runoff,peak flow and runoff coefficient continuously increase,causing higher flood risk,which is more obvious with shorter return period of rainfall.