Urban stormwater management using low-impact development control measures considering climate change

This work simulates rainfall using the GFDL-ESM2G large-scale model (from the Intergovernmental Panel on Climate Change-Fifth Assessment Report (IPCC-AR5)) and the change-factor method to downscale rainfall under three emission scenarios: RCP 2.6, RCP 4.5, and RCP 8.5. The Storm Water Management Model (SWMM) is applied to simulate stormwater driven by rainfall inputs in zones 1 and 3 of the northeastern municipality of Tehran under baseline (1988-2005), near-future (2030-2047), and far-future (2048-2065) conditions. The results indicate that the rainfall intensity for the design event with a 50-year return period would increase in the near future (2030-2047) and far future (2048-2065). Deployment of four types of low-impact development (LID) stormwater control measures (SCMs), i.e., vegetative swales, bio-retention cells, permeable pavement, and infiltration trenches for urban stormwater control in the study area, shows that there would be a significant change between the "with LID SCMs" condition and the "without LID SCMs" condition with respect to the flood volume at the basin outlet. The LID SCMs would reduce the flood volume in the near future by 22%, 23%, and 21% under the RCP2.6, RCP4.5, and RCP8.5, respectively, and they would reduce the flood volume in the far future by 23%, 27%, and 23% under the RCP2.6, RCP4.5, and RCP8.5 scenarios, respectively.