Investigating of the Existing Urban Drainage Systems for the Passage of Floods and the Possibility of Its Modification Using SWMM5 (Case Study: Darab county)

Today, with increasing urbanization and changing land border cities such as gardens, agricultural land, Barren land into residential areas, causing damage morphology and physical properties and hydrological basins are, This will redirect the natural flow of the water from rainfall and reduced infiltration basin is a result of problems such as flooding. Darab in Fars province and city in the study area were dry climate is Intense rains occur from time to time that the formation of rainfall runoff is significant BMP and LID are ahead in research techniques and strategies such as rain barrels, infiltration trenches, wells, Absorption, permeable flooring, bio-gardens and the use of storage tanks have been used and have shown good performance. Using information such as maps, land use, topography of the region, and rainfall statistics and modeling to model swmm5 After the reform and the implementation of the proposed method in comparison with the situation in the rain with a return period of ten years the peak runoff in the basin, 31% and maximum water level in the channel output to half the rate of 17.5% compared to current situation has increased infiltration basin In this study, we were able to construct 6 of 61 thousand cubic meters of rainwater storage tank to store it.