Hydrological Effect of Detention Ponds Based on SWMM

Storm management practices are widely used in urban areas for both peak flow reduction and environment improvement.Detention pond is a facility that uses orifice and weirs to detain and release the flow in a short period of time for peak flow reduction.ArcGIS and observation data are used to acquire the parameters for the SWMM model,and the impervious ratio is used here to show the pre-development and post-development condition of the area.Runoff generated by 2-year,10-year and 100-year designed storm is used to analyze the hydrological effect of the pre-development,post-development and detention pond.The results show that urbanization has increased peak discharge greatly and shortened runoff time.Detention pond is prominent in peak discharge reduction and can recover pre-development peak discharge.However,detention pond will not decrease the whole regional runoff.