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October 07, 2026
GeoSWMM 6.2 updates the computational engine to EPA SWMM 5.2.4 and introduces the new Transect Development Tool for preparing open-channel cross-sections within ArcGIS Pro.
This release expands GeoSWMM support for street and inlet modeling, culvert inlet controls, and analytical storage unit shapes. The new Transect Development Tool provides an integrated GIS workflow for developing, importing, reviewing, and managing channel geometry from terrain, GIS, and survey data.
GeoSWMM 6.2 requires ArcGIS Pro 3.7.0 or later, and ArcGIS Pro 3.7 requires Microsoft .NET Desktop Runtime 10 (x64). To upgrade, first install the required .NET runtime, then upgrade ArcGIS Pro, and finally install GeoSWMM 6.2. Before opening a project, confirm that the required GeoSWMM license is available.
GeoSWMM 6.2 uses the EPA SWMM 5.2.4 computational engine, which includes calculation updates and corrections from previous SWMM versions. As a result, simulation results may differ from those produced with earlier GeoSWMM versions. See the SWMM Library for additional information about SWMM engine updates. Projects created in earlier GeoSWMM versions are automatically migrated when opened in GeoSWMM 6.2, and GeoSWMM creates a backup of the project before migration.
GeoSWMM 6.2 is updated to the EPA SWMM 5.2.4 computational engine and expands support for SWMM capabilities including Streets and Inlets, culvert inlet controls, and analytical Storage Unit shapes.
GeoSWMM 6.2 now supports Street cross-sections, Inlet Designs, and Inlet Usage, allowing roadway flow and its capture by storm sewer systems to be represented directly within the model.
Modelers can define roadway cross-sections, create different inlet designs, and assign inlets to street conduits and receiving sewer nodes. Inlet placement can be defined as Automatic, On-Grade, or On-Sag, with inlet capture computed using SWMM 5.2’s FHWA HEC-22-based methodology.
Following a simulation, the Street Flow Summary provides key results such as peak flow, maximum spread and depth, inlet capture, bypass, and backflow.
The Conduit property editor now supports FHWA culvert inlet codes (1-57), allowing culvert inlet-control properties to be assigned directly to applicable conduits in GeoSWMM.
The Storage Curve Editor has been expanded to support additional Storage Unit geometry. In addition to Functional and Tabular storage curves, modelers can now define analytical storage shapes including Cylindrical, Conical, Paraboloid, and Pyramidal shapes. The required dimensions can be entered directly without developing a separate tabular storage curve.
GeoSWMM 6.2 introduces the new Transect Development Tool, providing an integrated workflow for preparing open channel cross-sections within ArcGIS Pro.
The tool allows modelers to:
This workflow brings channel geometry preparation into the GeoSWMM modeling environment and reduces the need to prepare cross-sections separately before adding them to a model.
GeoSWMM 6.2 introduces GIS Transects, a new spatial transect type stored as GIS features within the project. GIS Transects maintain the geographic location and alignment of each cross-section and obtain their elevation information from terrain data. If the channel geometry needs to be updated, the transect alignment can be edited using the Transect Development Tool and elevations can be updated from the DEM.
The traditional EPA SWMM transect format used in previous GeoSWMM releases is now referred to as a Tabular Transect. Tabular Transects store cross-section geometry as station-elevation data and can continue to be edited and assigned to open-channel conduits as before.
A GIS Transect can also be duplicated as a Tabular Transect, allowing modelers to manually modify station-elevation data when additional cross-section editing is needed.