What is GeoSWMM?

GeoSWMM is a hydrologic, hydraulic and water quality model integrated with ArcGIS®. It allows users to simulate flow, velocity of water, depth of water and water quality for projects ranging from a simple site development to a complex urban watershed involving open channels, sewers, pumps, hydraulic structures and Best Management Practices (BMPs). GeoSWMM is built upon EPA’s SWMM 5 model which requires users to manually enter data through its interface. GeoSWMM makes the input data preparation extremely easy and efficient through the ArcMap™ based tools, geodatabase and mapping features.

What are the typical applications of GeoSWMM?

GeoSWMM can be used to model


Designing wastewater
collection system/sanitary
sewer design and analysis


Developing control strategies
to minimize combined
sewer overflows (CSOs)


Evaluating the impact
of inflow and infiltration (I/I)
on sanitary sewer overflows (SSOs)


Estimating runoff
due to rainfall and snowmelt


Design and sizing
of drainage system components
for flood control


Flood plain
mapping of natural
channel systems


Modeling water
quality loads from
non-point sources


Designing and estimating
the effectiveness of Best
Management Practices (BMPs) and
Low Impact Developments (LIDs)

How is GeoSWMM different from other hydrologic and hydraulic models?

Considering the variations that are available from different vendors, EPA’s SWMM 5 is the most widely used model for urban drainage as well as sanitary sewer systems. Compared to other commonly used hydrologic (e.g. HEC-HMS, HSPF, etc.) and hydraulic (e.g. HEC-RAS) models SWMM is unique because of its ability to simulate hydrology (i.e. the rainfall-runoff processes that generate flow) and hydraulics (i.e. open channel flow with backwater, flow through closed conduits, pumps and hydraulic structures, etc.) within the same model. The model can be used for a single event or a long-term simulation. Streams Tech provides SWMM resources for interested users.

Any experienced modeler would agree with the fact that a user would spend the most of his/her modeling time on preparing input data. By integrating SWMM with ArcMap, GeoSWMM helps users to significantly reduce the time it takes to prepare model input, increase the accuracy of input data, store and manage data in a database environment and visualize and inspect model objects on a map. It allows users to run simulation and view output without ever exiting the GIS environment.

Users all over
the world using

GeoSWMM Highlights

100% Compatible with EPA’s SWMM 5, which is approved by FEMA for the National Flood Insurance Program (NFIP)

No Learning Curve for ArcGIS® and EPA SWMM 5 Users

Model setup, simulation and output visualization completely within ArcGIS®

Unrestricted access to ArcMap functionalities

Support of queries and reporting of data stored in a file Geodatabase

Tabular view of input and output data

Import and Export SWMM 5 input file

Special Tools

 Watershed Delineation tool (requires ArcGIS® Spatial Analysis)

 Network Analysis tool

 SWMM 5 User’s Manual

 Subcatchment characteristic Width Calculation tool

 Subcatchment Slope Calculation tool (requires ArcGIS® Spatial Analysis)

 Subcatchment Imperviousness Calculation tool

 Subcatchment Land Use Properties tool

 Conduit Roughness selection tool

 Model creation from existing GIS data

 Automatic calculation of geometric properties of model objects

 Import from and export to SWMM input file

 Control rules editor

 Enhanced tabular view of model data

 View Profile Plot

 View Time Series Plot

 View Time Series Comparison