The SWMM file format is a specialized data format used by the Storm Water Management Model, a comprehensive simulation tool originally developed by the United States Environmental Protection Agency (EPA). This format is essential for hydraulic and hydrologic modeling, specifically designed to simulate the quantity and quality of runoff from urban environments. A SWMM file typically stores complex data structures representing subcatchments, conveyance networks, and treatment facilities. It includes parameters for rainfall, evaporation, infiltration, and flow routing through pipes, channels, and storage units. Engineers and urban planners utilize this format to predict the impact of storm events on drainage infrastructure, design sustainable urban drainage systems (SuDS), and manage combined sewer overflows. While the core EPA engine often uses text-based .inp files, the .swmm extension is frequently employed by various graphical user interface wrappers and commercial software packages to bundle project settings, spatial data, and simulation parameters into a single manageable project file for environmental engineering analysis.