Home / OpenFlows SewerGEMS

OpenFlows SewerGEMS

OpenFlows Software Logo White

OpenFlows SewerGEMS

Urban Sanitary and Combined Sewer Modeling Software

Produce Optimal Urban Sewer Planning and Overflow Remediation Analysis Designs

Model from within several platforms while accessing a single, shared project data source.


OpenFlows SewerGEMS enables you to produce optimal urban sewer planning and overflow remediation analysis designs in an easy-to-use environment. You can design and operate sanitary or combined conveyance sewer systems by using built-in hydraulic and hydrology capabilities with a variety of dry- and wet-weather calculation methods. Better understand surface flood depth and velocity, flood hazard, and inundation times with the new user-friendly 1D/2D hydraulic analysis capability.

Access A Single, Shared Project Data Source

Collaborate without surrendering individual skills, maintaining a single modeling data set without restrictions. Model within Windows, ArcGIS, AutoCAD, OpenRoads, OpenSite, or OpenRail.

1D/2D Hydraulic Analysis

User-friendly tools connect 1D network elements with 2D surface flows. Better understand surface flooding depth and velocity, flood hazard, and inundation times, and communicate this information to stakeholders with versatile mapping and reporting tools.

Understand Results More Easily

Spot bottlenecks and potential surcharging with animated 3D graphs and profiles. Use color coding, element symbology, and annotation to visualize input and results.

Easy Model Management With Scenarios

Configure, evaluate, visualize and compare an unlimited number of scenarios within a single file.

Leverage Existing Data

Use your CAD drawings, GIS files, SWMM, SCADA data, databases, and spreadsheets to jumpstart the model-building process.

Input And Save Unlimited Flow Patterns

Model flow changes over the course of a day. Load models with wet weather runoff flows from precipitation using built-in rainfall distributions or user-defined rainfall events.

OpenFlows SewerGEMS is a superset of OpenFlows SewerCAD, CivilStorm and StormCAD.

*Prices vary per region. For more options, see licensing and subscriptions section.

User Quote

"The new 1D/2D functionality in OpenFlows SewerGEMS is a powerful tool for flood modeling and hydraulic analysis of stormwater systems overflowing. The user-friendly interface and intuitive surface grid creator make working with real surface areas easy and fun. It provides comprehensive visualization options, both with in-built and external tools. As we deal with climate change, it is imperative to be able to prepare for new challenges in water retention in both urban and city environments.."

— M.Sc. Eng. Paweł Suchorab, Faculty of Environmental Engineering, Lublin University of Technology


OpenFlows Software Resources

Frequently Asked Questions

Easy-to-use advanced engineering software, you can use SewerGEMS to analyze, design, and operate sanitary and combined sewer systems. Decrease decision risks by ensuring that the model uses the best available data, built-in hydraulic and hydrology capabilities, and a variety of wet-weather calibration methods. Create what-if scenarios to gain a better understanding of wastewater systems to make smarter decisions and improve your response times. SCADA integration provides you with reliable model results, improves capacity and limits sewer overflows, which ultimately enable you to comply with sewer regulations set by regulatory agencies.

The price of OpenFlows SewerGEMS varies per region. While there are various types of licensing available, a common choice is the 12-month practitioner license offered through Bentley’s eStore. When you purchase through eStore, you get a Virtuoso Subscription. This means you get the software and “Keys” (tokens) to redeem for customizable training, mentoring, and consulting services.

In SewerGEMS, you can assign sewer loads based on a variety of GIS-based sources such as customer water-use billing data, area-wide flow measurement, or polygons with known population or land use. Input and save an unlimited number of flow patterns, to accurately model flow changes over the course of a day. Load models with wet weather runoff flows derived from precipitation, using built-in rainfall distributions, or user-defined rainfall events. Runoff flows are modeled and calibrated using a choice of hydrograph methods, including RTK, SCS, Modified Rational, EPA-SWMM, or user-defined generic unit hydrographs. Users can also load the model based on property connections. Loading can be applied as user-defined hydrographs, pattern-based loads, and unit loads. Access and customize the comprehensive unit (dry weather) load engineering library with numerous typical unit loads based on population, area, count, and discharge.

When analyzing, switch among multiple solvers, according to the type of system you are using. To solve the Saint Venant equations, choose between SewerGEMS’ explicit EPA solver based on SWMM and the implicit dynamic wave engine. These two dynamic engines account for storage effects within structures and quantify overflows should they occur. The convex/gradually varied flow solver uses convex routing to determine gravity sewer flows and gradually varied flow (backwater analysis) to determine hydraulic properties once the flow is known. With the rational/gradually varied flow solver, peak flows in the storm sewer system are calculated using the rational method. Use this solver to analyze peak flow conditions, or to automatically design storm sewers.

SewerGEMS is a superset of Bentley’s solutions for wastewater (SewerCAD) and stormwater (CivilStorm and StormCAD) network analysis and design.

  • SewerGEMS includes a standalone version plus the ability to integrate with three platforms MicroStation, AutoCAD, and ArcGIS. SewerGEMS’ full GIS, CAD, and SCADA interoperability enables the cost-effective sharing and flow of information between utilities’ design, engineering, GIS, and operation departments, and their consultants.
  • SewerCAD has a gradually varied flow engine for steady-state and extended period simulations for system design and rehabilitation that analyzes sanitary sewer networks under peak flow conditions with convex routing hydraulics. SewerGEMS uses a fully dynamic engine to help you accurately model looped networks, flow splits, overflows, and storage capacity. CivilStorm analyzes, designs, and operates stormwater systems. It is a fully dynamic, multi-platform, hydraulic modeling solution developed for the analysis of complex stormwater systems. StormCAD provides calculations for catchment runoff, inlet capacity, and gutters and pipe network flow with rational method peak flows

No. SewerGEMS can be used as a standalone product. Additionally, enjoy the power and versatility of working across multiple applications with superior interoperability. Choose from Windows standalone, ArcGIS for GIS integration, MicroStation, and AutoCAD.

No. Unlike other platforms, SewerGEMS includes all calculation capabilities.

SewerGEMS has an easier to use interface.

Refer to the ‘System Requirements’ section of the Data Sheet.

Platform pre-requirements
SewerGEMS runs without platform restrictions as a standalone application. It also runs from within ArcGIS, AutoCAD, MicroStation, OpenRoads Designer, OpenRail Designer, and OpenSite Designer.

Licensing and Subscription options

Choose What is Right for You

One-year license with training

Virtuoso Subscription – A popular choice for small and medium-sized businesses

Get access to software that comes with training – fast! Bentley’s eStore, Virtuosity, offers a convenient way to lease a 12-month license of Bentley software for a low, upfront cost. Every online purchase through Virtuosity comes as a Virtuoso Subscription that includes training and auto-renewals.

With no contract required, it’s easy to get started quickly.

Shop Now

One-time purchase with support

Perpetual License with SELECT

A perpetual license of Bentley software is a one-time purchase, with a yearly maintenance subscription, called SELECT. This includes 24/7/365 technical support, learning resources, and the ability to exchange licenses for other software once a year. With SELECT, you will benefit from:

  • License pooling, so you can access your software from multiple computers.
  • Access additional Bentley software with Term Licenses, which allow you to pay for what you use without the upfront cost of purchasing a perpetual license.

Annual renewal quotes are delivered directly to your inbox, and our experienced Renewal Representatives are available to answer your questions and guide you through any changes you’d like to make.

Contact Us

Enterprise Organizations

We’ve got your back

For larger organizations with in-depth requirements, we offer plans to provide global pricing and access to our comprehensive portfolio of solutions and success plan services. Contact us about how to get access to software, global best practices, implementation services, training, and technical support to help your organization realize its full potential while addressing your unique needs.

Contact Us

Best-Selling Water Resources Textbook

Computer Applications in Hydraulic Engineering

This fully updated 9th edition textbook is available for download! Ideal for engineers and students in hydraulics and hydrology, offering theory and real-world applications with problem-solving and modeling exercises featuring OpenFlows WaterGEMS, HAMMER, SewerGEMS, SewerCAD, PondPack, StormCAD, FlowMaster and CulvertMaster.

Design and Operate Urban Sanitary and Combined Sewer Systems

Celebrate Infrastructure Delivery & Performance Excellence

The 2024 Year in Infrastructure
and Going Digital Awards

Nominate a project for the most prestigious awards in infrastructure! Extended deadline to enter is April 29th.