Prince Trinidad-Rhodius
This tutorial series demonstrates an integrated Civil 3D and InfoDrainage workflow for preliminary stormwater design—from the initial site plan and pipe network through hydrologic analysis, hydraulic modeling, detention pond sizing, and design reporting.
Want to follow along with the tutorials? We’ve put together a demo dataset containing the files used throughout all five workflows.
The dataset is organized into 5 folders, one for each workflow video in this series so you can easily find the files you need as you progress through the preliminary stormwater design.
Download the demo dataset below.
Stormwater design often begins in Civil 3D, then moves through hydrology, hydraulic sizing, storage design, and reporting. Each handoff can add manual work, especially when the site changes and information must be updated in more than one place.
This five-part video series follows one conceptual development site through a practical preliminary design workflow. Starting with a Civil 3D pipe network and catchments, we will move the project into InfoDrainage, establish the rainfall and runoff inputs, size the storm network, add and refine a pond, prepare review-ready outputs, and automate catchment properties for future design revisions.
The value of that continuity adds up. Bluefield Research found that integrated workflows saved approximately 17 hours on a typical 80-hour drainage design project, or about 21% of the total design time.
These videos are designed to be watched as a series, with each workflow building on the same model using a realistic site. Together, they show how a stormwater engineer can move from a conceptual site plan to a preliminary system that is analyzed, documented, and ready to submit.
📚 Read more about how integrated drainage design can help stormwater engineers deliver stormwater projects 21% faster.
1. Start with Civil 3D and build the InfoDrainage model
The series begins where many civil design teams already work in Civil 3D. The first tutorial shows how to export the preliminary pipe network and catchments into InfoDrainage, map the network components, and bring in the CAD base plan and surface information needed to analyze the site.
This creates the foundation for the remaining videos. The network geometry, catchments, naming, and site context are carried into the hydraulic model without rebuilding the project from scratch. The same connection can later be used to return updated pipe sizes, inverts, and other design changes to Civil 3D.This interoperability helps civil and stormwater engineers maintain a more connected design process as the site layout and drainage model evolve.
📚 For a deeper look at the connection between the two applications, read how InfoDrainage integrates with Civil 3D and how this drainage integration has grown rapidly.
2. Configure the hydrology and size the storm network
With the site data properly added into the model, the next step is to analyze the storm sewer network and ensure it is sized correctly. The second tutorial sets up project rainfall data, assigns the runoff method and time of concentration, validates the model, and selects the design event used for preliminary pipe sizing.
The Network Design Wizard then evaluates a selected pipe length (flow path) and updates pipe sizes and elevations based on the chosen criteria. The proposed changes can be reviewed in the design report and profile before they are accepted, giving the engineer a fast starting point that can still be adjusted for site constraints and local standards.
The result is not a locked final design, but a preliminary stormwater network that gives the engineer a defensible starting point for further hydraulic analysis and design iteration.
By the end of this video, the conceptual layout has become a preliminary sized network that can be imported back into Civil 3D or carried forward into the pond design.
📚 Did you know that Civil 3D added drainage design capabilities, replacing the old SSA? These new Civil 3D options are powered by InfoDrainage. We wrote an article that walks through a detailed comparison of InfoDrainage and the drainage tools in Civil 3D.
3. Add and refine a preliminary pond
Once the conveyance system is established, it is now time to define the downstream stormwater storage. Using a pond outline from the CAD base plan, the third tutorial will show you how to create the pond geometry and define its elevations, depth, freeboard, side slopes, and other properties.
The Quick Storage Estimate provides an initial storage volume using the drainage area, runoff coefficient, rainfall, and allowable discharge rate. After the inlet and outlet are connected, the model is simulated to identify the critical storm and the maximum volume stored in the pond. Those results are then used to refine the pond and size it to accommodate the storage.
This keeps the pipe network and storage facility in one hydraulic model, making it easier to understand how the full system performs while the site plan is still developing.
📚 Pond sizing is more than a volume calculation. Designers also need to consider discharge control, water quality, freeboard, site geometry, safety, maintenance, and how the pond behaves across multiple storm events. Our guide to ponds and infiltration basins in sustainable drainage design explores these considerations in more detail.
4. Document your model reports and results for review
With the preliminary network and pond simulated, the next step is to organize the results for design review and documentation. The fourth tutorial covers the detailed reporting options in InfoDrainage and shows how to select the storms, model components, analysis criteria, and result summaries that should be included.
Flexible Reporting provides a focused alternative when only selected information is needed. Pipe properties, inverts, slopes, hydraulic grade line elevations, capacity results, catchment areas, runoff coefficients, and other fields can be assembled into a custom table and exported for use in Excel or existing report templates.
The video also introduces Transmit Design, which packages the model with its supporting CAD, surface, and result data so the project can be shared with the accommodating information.
📚 Because the report is connected to the model, it can also be refreshed as the design changes, reducing the need to rebuild tables manually after every iteration. Learn more about Flexible Reporting and enhanced Civil 3D integration in InfoDrainage.
5. Keep catchment properties automated as the site changes
A preliminary design will usually go through several site-plan revisions. The final tutorial adds automation that updates catchment properties without repeating the same hydrologic calculations manually.
Land-use and soil polygons are imported from CAD or GIS and applied beneath the model catchments. InfoDrainage uses those layers to calculate runoff coefficients, imperviousness, and curve numbers. When a catchment is moved, reshaped, or reoriented, the values update with respect to the underlying land-use and soil areas within the revised boundary.
This workflow shows how the completed preliminary model can remain useful as the design evolves. It reduces spreadsheet updates and helps keep the hydrologic inputs aligned with the latest site plan.
💡 Automation becomes particularly valuable during preliminary drainage design, when grading, roads, buildings, parcel boundaries, and impervious areas may all change several times before the design is finalized. Rather than treating each change as a manual recalculation exercise, the model can respond to the updated site geometry.
From conceptual site plan to preliminary stormwater design
Together, these five tutorials turn a conceptual Civil 3D plan into an InfoDrainage model with a fully sized stormwater management system that is analyzed, report-ready, and easy to update.
The finished preliminary model includes:
- Civil 3D pipe-network and catchment data
- Defined rainfall and runoff inputs
- A preliminarily sized storm sewer network
- A simulated and refined stormwater pond
- Review-ready model results and reports
- Catchment properties that update automatically with site-plan revisions
Other helpful resources
- Free trial: Try InfoDrainage yourself by downloading a free trial for 30 days (no credit card required). Are you a student or educator? You can use our water software for free.
- Tech specs: Dig into the InfoDrainage Technical Information Hub and examine how the software conforms to industry standards.
- New to SuDS? Watch our ‘Fundamentals of Drainage Design’: a framework with 8 steps video.