Advanced SWMM Modeling Support

Stormwater Modeling Capabilities

StormNET is a fully-dynamic hydrology and hydraulic model that can analyze both simple and complex stormwater systems. StormNET can be used for:

• Stormwater sewer networks and interconnected detention ponds
• Subdivision drainage design
• Automatic sizing and designing of detention ponds
• Stormwater master planning
• Watershed master planning
• Bridge and culvert modeling, including roadway overtopping
• Water quality studies

StormNET can simultaneously simulate dual drainage networks (stormwater sewer network and city streets as separate but connected conveyance pathways) and inlet capacity. It will quickly determine the amount of stormwater flow that is intercepted by the stormwater network inlets and the amount of stormwater flow that bypasses and is then routed further downstream to other inlets. Hydraulic network modeling is performed by the full set of Saint Venant equations or by the Kinematic Wave method. StormNET can account for:

• Storm sewers and sanitary sewers
• Open channels
• Streams
• Bridge and culverts
• Curb and gutter inlets
• Detention ponds and outlet structures
• Flooding overflows
• And more…

Advanced Capabilities

StormNET’s advanced SWMM features and capabilities include:

• Easy to use graphical interface
• Integration with AutoCAD and GIS
• Automatically construct network sewer models from AutoCAD and MicroStation drawings, GIS geodatabases
• Linkage through LandXML and GIS shapefiles

• Importing of XP SWMM, PC SWMM and other models

• Automatic Detention Pond Sizer and Pond Designer
• Size and design a pond and corresponding outlet structure in minutes
• Account for basin infiltration
• Model subsurface vaults or systems of large diameter interconnected storage pipes, arched pipes, or manufactured storage chambers

• Rainfall Designer
• Automatically determine design rainfall (based upon study location) for 1, 2, 5, 10, 25, 50, and 100 year return frequencies using StormNET’s site-specific storm distribution database with over 3,500 up-to-date rainfall recording stations across North America
• Define any storm duration, multiple storm events
• Numerous storm distributions, including SCS, Huff, Eastern Washington, Florida, Chicago Storm, Hurricane Hazel, etc.

• Numerous hydrology models supported, including:
• US EPA SWMM 5.0 (imports XPSWMM™ v10.52 and EPA SWMM v4.4 and earlier)
• NRCS (SCS) TR-55
• NRCS (SCS) TR-20
• US Army Corps HEC-1
• Rational Method
• Modified Rational Method
• DeKalb Rational Method
• Santa Barbara Unit Hydrograph
• Delmarva Unit Hydrograph
• Long-Term Continuous Simulation
• Maricopa & Pima Counties (Arizona) Papadakis-Kazan methodology
• Harris County (Texas) Method
• LA County MODRAT2 and F0601 (in development)
• CUHP Colorado Urban Hydrograph Procedure (in development)
• WWHM Western Washington Hydrology Model (in development)
• HEC-HMS (in development)
• And more…

• Adjust hydrograph shape factor:
• Select from pre-defined shape factors
• Assign user-defined shapes

• Account for complex flow conditions, including:
• Subcritical, critical, and supercritical flow regimes
• Gravity and pressurized flow
• Flow reversals
• Flow splits and combines
• Branched, dendritic, and looped systems
• Tailwater submergence effects
• Interconnected ponds
• Tidal outfalls
• More…

• Model complex flow structures, including
• Detention ponds, retention ponds, underground storage structures
• Multi-port risers, composite weirs, multiple orifices outlet structures
• Pumps, lift stations, force mains
• Flow diversions
• Real time controls
• Other complex hydraulic flow structures

• Account for head losses, including:
• Entrance losses
• Exit losses
• Friction losses
• Bend losses
• Drop losses

• Account for water quality, including:
• Dry-weather pollutant buildup over different land uses
• Pollutant washoff from specific land uses during storm events
• Direct contribution of rainfall deposition
• Reduction in dry-weather buildup due to street cleaning
• Reduction in washoff load due to BMPs
• Entry of dry weather sanitary flows and user-specified external inflows at any point in the drainage system
• Routing of water quality constituents through the drainage system
• Reduction in constituent concentration through treatment in storage units or by natural processes pipes and channels

Easy to define water quality parameters

Spatial Reporting

StormNET can plot analysis results directly on the plan and profile views, showing peak flows, depths, flood elevations, maximum velocities, etc. Model results on the plan view can be plotted in which the color and size of the pipe and manholes are dependent on the model results. Both the plan view and profile plot can be animated to show the results varying with time.

Animated profile plots illustrate how additional storage can attenuate overflows

Color-coded plan view allow you to quickly find bottlenecks

View tabular data within Microsoft Excel, including input data and analysis results