Automated Calibration of the EPA-SWMM Model for an Impact of Land Use and Land Cover Changes on Peak Discharge for a Sub-Urban Catchment of Delhi

Abstract

The Environmental Protection Agency's (EPA) Storm Water Management Model (SWMM), USA is a dynamic hydrologic-hydraulic model that simulates the amount and quality of runoff from urban areas. It is broadly used for planning, analysing, and designing storm water runoff, combined and sanitary sewers, and other urban drainage systems. SWMM can solely be used to do the modelling of urban drainage systems. However, SWMM can be automated and convert model files to and from GIS data using R programming, allowing for more in-depth analysis and visualization. Automatic calibration is also a promising alternative, ideally supporting a user-independent and time-efficient method for estimating model parameters. This study investigates the impact of Land Use and Land Cover (LULC) variation on peak discharge at the outfall of the Najafgarh-Mahipalpur drain during rapid urbanization from 2005 to 2022. The findings show that the historical LULC fluctuation for seventeen years resulted in a nearly 28% rise in the peak flow rate at the outfall, according to SWMM simulation. The findings of this study could serve as a guide for planning and managing urban flooding in cities that are rapidly expanding, particularly in developing countries.