As cities expand and climate change intensifies rainfall patterns, urban planners and engineers face unprecedented stormwater management challenges. Increasing impervious surfaces, overloaded sewer networks, and frequent urban flooding require accurate, efficient modeling tools. ArcGIS Pro, enhanced by GeoSWMM’s seamless integration of USEPA’s Storm Water Management Model (SWMM), empowers professionals by converting spatial data into actionable insights for stormwater management. 

ArcGIS Pro is the industry-standard desktop GIS software designed for visualizing, analyzing, and managing spatial data. Supporting both 2D and 3D mapping, ArcGIS Pro allows users to explore, manipulate, and visualize data effectively and build custom applications tailored to specific engineering needs. 

2D Urban Flood Inundation Mapping in ArcGIS Pro

When integrated with ArcGIS Pro, SWMM provides a comprehensive tool for simulating how stormwater moves through urban landscapes. This integration not only facilitates more accurate system design but also improves decision-making and risk communication. 

The successful use of SWMM—a robust hydrologic, hydraulic, and water quality model—depends significantly on the quality and accuracy of spatial input data. Essential SWMM inputs like storm sewers, manholes, open channels, subcatchment boundaries, impervious areas, soils, and urban structures are inherently spatial. ArcGIS Pro excels in accurately extracting, managing, and visualizing this spatial data, which makes it indispensable for stormwater modeling. 

The following sections outline how ArcGIS Pro tools effectively prepare key SWMM inputs: 

Subcatchment Boundaries and Slopes 

Catchments define drainage areas contributing to an outlet’s flow. Dividing catchments into smaller subcatchments discretizes the drainage area as a mosaic of smaller subareas having uniform characteristics and provides a better representation in the model. ArcGIS Pro tools such as Flow Direction, Flow Accumulation, and Basin utilize Digital Elevation Models (DEMs) to automatically delineate catchments and subcatchments. Additionally, the Slope, Aspect, and Fill tools enable detailed analysis of slope, elevation changes, and depression zones. GeoSWMM simplifies this complex workflow by providing an intuitive interface that automates subcatchment delineation. 

Impervious Areas

Accurate identification of impervious areas is critical for estimating runoff. ArcGIS Pro tools like Zonal Statistics, Reclassify, and Raster Calculator help generate spatially varying hydrological properties. However, working with raster data and converting between raster and vector formats require care and practice. GeoSWMM streamlines this process with automated tools specifically designed for imperviousness calculations. 

Hydrologic Parameter Estimation

Overlaying soil, land use, and subcatchment data in ArcGIS Pro enables automatic assignment of hydrologic parameters such as surface roughness, infiltration rates, and depression storage. Tools like Intersect, Join, Field Calculator, and Spatial Join facilitate these assignments but require meticulous data management. GeoSWMM offers a user-friendly interface that simplifies parameter estimation, maintains data integrity, and reduces potential errors. 

Stormwater Infrastructure

Stormwater Network Connectivity Check and QA/QC in ArcGIS Pro with GeoSWMM

Creating and managing GIS data for stormwater infrastructure (pipes, manholes, outfalls, catch basins) requires precision. ArcGIS Pro’s Create Features, Snap, Topology, and Attribute Rules are essential tools, demanding familiarity with best practices and geodatabase management. GeoSWMM enhances these capabilities by providing specialized tools for topology validation and attribute quality assurance, significantly simplifying the workflow. 

Urban Infrastructure and Hydraulic Barriers

Buildings, roads, walls, and other urban features often obstruct natural drainage, causing flooding and ponding. ArcGIS Pro tools like Zonal Statistics, Overlay analysis, and Map Algebra help identify these barriers and evaluate their hydraulic impacts. GeoSWMM further simplifies this critical assessment by automating mesh generation for 2D modeling, facilitating accurate flood mapping, and evaluating urban infrastructure effects efficiently. 

Spatial Data Management and Editing 

ArcGIS Pro offers robust tools like ModelBuilder, Python Notebooks, and Field Calculator to automate data workflows. However, these tools require programming and GIS expertise. GeoSWMM addresses this challenge by providing a robust, programming-free toolset that eliminates potential errors and streamlines the modeling process. 

Analyzing Stormwater System Performance with Water Elevation Profiles in GeoSWMM

Accelerated Model Building and Quality Assurance Using GeoSWMM

GeoSWMM integrates complete stormwater modeling functionality directly within ArcGIS Pro, effectively bridging the gap between physical geography and hydrologic and hydraulic theories, making the model more reliable and actionable. It offers the following key benefits:

• End-to-end modeling workflow inside ArcGIS Pro 
• Native use of feature classes and geodatabases 
• Automated parameter estimation 
• Seamless updating of stormwater networks and attributes 
• Advanced flood mapping and results analysis 

By eliminating fragmented data workflows and complex model setups, GeoSWMM ensures efficient data transfer, effortless updates, meaningful visualization, and easier collaboration among teams. Ultimately, GeoSWMM transforms ArcGIS Pro into an engineering-grade platform, equipping urban planners and engineers with essential tools for enhancing urban resilience and managing water quality. 

Try GeoSWMM now.