Compare
Same job. Different desks.
Public list prices as of 2026. Features are the common case, not every add-on. StormDesigner Release 1 is DA, ditches, pipes, report, plus hydrograph and pipe-network layout. Full hydro Run and HGL are later.
| StormDesigner | HydroCAD | Hydraflow Storm Sewers | Bentley OpenFlows Storm | Autodesk InfoDrainage | |
|---|---|---|---|---|---|
| Where it lives | Exe next to Civil 3D. Named pipe. | Standalone. Import / export. | Civil 3D extension. | Standalone + Bentley CAD. | Standalone. Round-trip to Civil 3D. |
| Project file | .sdp with cached rings | .hcp | .stm + DWG | Bentley model | InfoDrainage + DWG |
| Online USDA soils | Yes | No | No | GIS import | GIS / mapping |
| NOAA Atlas 14 | Yes, in the .sdp | Rainfall library | IDF you load | Yes | Yes |
| PRE / POST drainage areas | Release 1 | Subcatchments | Inlets, not DA overlay | Yes | Catchments |
| Ditch / swale calc | Release 1 | Reaches | Pipes | Channels | Yes |
| Single pipe calc | Release 1 | Culverts / reaches | Network | Yes | Yes |
| Pipe network HGL / EGL | Layout now. HGL Run later | Not the point | Yes | Yes | Yes |
| Hydrographs / ponds | Nodes now. Run later | Core product | No | PondPack in the bundle | Yes |
| Calculation report | PDF in the .sdp | Built-in reports | Print from the extension | Yes | Yes |
| Civil 3D still required to design? | To draw. Not to open last rings. | No CAD required | Yes | Optional CAD host | Optional round-trip |
| List price (public) | $90 / mo or $695 / yr | From $195 / yr or $295 once | Tied to Civil 3D | From $1,355 / yr | Autodesk subscription |
| Try before you buy | 30-day trial. Ask. | Sampler / eval | With Civil 3D trial | Sales / trial | 30-day trial |
This table is a buying aid, not a lab report. If a cell is wrong, mail support@stormdesigner.net and I will fix it.