Four calculation engines — Sedimentology, Water Quality, Hydrology & Hydraulics, Conveyance — with live USDA soil data, NOAA rainfall, and physics-based BMP routing. In a browser.
14 days free. No credit card. 42 test suites passing.
The tools work. But the way they work hasn't kept up with how engineers actually build projects today. And the price hasn't gotten any more reasonable — perpetual licenses still run $3,000 to $8,000 per seat, locked to a single machine.
Legacy tools are Windows executables. No collaboration, no browser, no mobile. License tied to one machine. Work from a jobsite or a different office? Too bad.
You get a number. You can't see the formula, the substitution, or the intermediate steps. Review takes longer than it should because you're reverse-engineering output instead of reading it.
Hydrology in one app, sediment in another, water quality in a third. Copy-paste between them. Re-key inputs. Hope nothing drifts between analyses that should share the same watershed data.
HydroComplete models your entire site as a connected system. Watershed properties feed into BMPs, BMPs chain together, and pollutant removal compounds through the train — all in one project, with one set of inputs.
USDA SSURGO soil properties, NOAA Atlas-14 rainfall depths, NLCD land cover, and 3DEP elevation — all from one map click. No more toggling between Web Soil Survey, PFDS, and the NLCD viewer.
Stokes/Rubey settling velocity for each particle bin. Camp-Hazen basin trap efficiency. Darcy's law through bioretention media. Kadlec k-C* wetland kinetics. Real equations, not interpolated charts.
KaTeX-rendered formula steps for every result: the equation, the substitution with your inputs, the computed value, and the published reference. If a reviewer asks where a number came from, point at the screen.
Modified Puls detention routing, auto-sized orifice, pre/post comparison table. Build both conditions in the same project and generate the comparison deliverable without switching tools.
Each engine implements the published, peer-reviewed equations directly. No wrappers around someone else's code. No lookup-table interpolation pretending to be physics.
How it's different: resolves particle-size distribution across 7 bins instead of treating sediment as a single bulk value. Every settling calculation uses actual grain diameters.
How it's different: chains BMPs into a treatment train with compounding removal, not isolated percent-removal assumptions. Pollutant concentrations propagate through each stage.
How it's different: pre-dev and post-dev share one project with linked watershed data. Change a CN and both hydrographs update — no re-keying between files.
How it's different: solves normal and critical depth iteratively instead of requiring you to guess-and-check. 14 cross-section shapes, not just circular and trapezoidal.
Every number independently verifiable. Every formula published with its reference.
Real-time data pulls from four federal agencies. Draw a site boundary and get soil properties, design rainfall, land cover, and elevation in one request. No more toggling between government websites.
This replaces the manual SSURGO/NOAA lookup workflow that typically takes 30+ minutes per site — navigating Web Soil Survey, downloading PFDS tables, cross-referencing NLCD pixels. One click, four federal datasets, done.
14-day free trial on every plan. No credit card required to start. The trial is fully functional — all four engines, unlimited projects, real PDF reports. Not a limited demo with features locked behind a paywall.
14 days free, no credit card
14 days free, no credit card
Honest answers. No marketing spin.
HydroComplete runs in a browser on any platform, renders every formula on screen, chains BMPs across engines in a single project, and stores projects in the cloud. It is not a drop-in HydroCAD replacement for detention routing workflows specifically — HydroCAD has decades of refinement there. HydroComplete does implement Modified Puls reservoir routing through its Hydrology & Hydraulics engine, which covers most detention-pond analyses.
The engines use published, peer-reviewed equations: RUSLE from USDA ARS, MUSLE from Williams (1975), SCS Unit Hydrograph from NRCS TR-55, Modified Puls routing from USACE / HEC-22, Manning's equation from Chow (1959).
Every result is shown with its formula, the substitution using your inputs, and the computed value — so you (or your reviewer) can verify each step by hand if you want to.
The Sedimentology engine implements the same RUSLE / MUSLE soil loss methods and the same trap efficiency calculations as legacy sediment tools. The Water Quality engine implements 15 BMP types with water-quality-volume sizing and buildup / washoff pollutant loading.
Honest answer: the original desktop apps are still authoritative for some specialized workflows, and we don't pretend otherwise. HydroComplete is designed to cover the core day-to-day use cases with better transparency, better integration across engines, and a modern interface.
Trial reports are watermarked "TRIAL - NOT FOR REGULATORY SUBMITTAL" on every page. Subscriber reports are clean and include the engineer-of-record information you enter in project settings. Applying the PE seal is the user's responsibility under the rules of the state where the work is performed — HydroComplete generates the deliverable, you stamp it.
The editor loads in your browser, but calculations run on our server through an authenticated API so the engines stay consistent across users and versions. There is no offline mode right now. You need an internet connection to compute.
Through the Stripe customer portal, any time, in about three clicks. There is no contract, no cancellation fee, and no "call us to cancel" routine.