SWATGenXAbout SWATGenX
SWATGenX turns public national data — NHDPlus HR hydrography, gSSURGO soils, NLCD land cover, PRISM climate — into complete, inspectable SWAT+ models for any USGS gage, HUC12 outlet, or HUC8 basin in the country. Built and maintained independently, with no institution behind it and nothing hidden inside it.
Independent, self-funded, and open to inspect before anyone signs up.
SWATGenX was built because watershed modeling should no longer depend on outdated, fragmented, coarse-scale workflows. We need a centralized, inspectable pipeline that uses high-resolution national data to prepare SWAT+ models consistently across the CONUS, so a model built for one watershed shares the same modeling backbone, rules, and scale logic as a model built anywhere else.
SWATGenX exists to move practitioners past the slowest part of modeling: building the model. Clipping, routing, weather, soils, land cover, QA, file preparation, and calibration all run end to end as one automated pipeline—a model arrives built and calibrated, not as a starting point for weeks of setup. That leaves users their expertise for the work that actually changes decisions: analysis, TMDLs, BMP targeting, contaminant transport, and watershed management.
National watershed modeling should not mean coarse watershed modeling. Local decisions require local detail—small channels, ponds, subbasins, and catchments that coarse frameworks often smooth away. SWATGenX uses NHDPlus HR to bring national-scale automation closer to the resolution needed for township-, neighborhood-, and BMP-scale decisions.
SWATGenX is not locked behind a registration wall. It is open to inspect before anyone commits. Visitors can explore the app, navigate the Watershed Explorer, and download example model packages without being forced to register.
Our mission is to make high-quality watershed model preparation scalable. SWATGenX does not replace hydrologic judgment, calibration, or validation—it removes the repetitive data-engineering burden so you reach modeling work faster.
Let modelers spend less time assembling inputs and more time understanding watersheds.
What we deliver
What we do not claim
We do not claim that every generated model is calibrated, validated, or ready for regulatory use. Treat downloads as model-ready starting points: inspect, calibrate, and validate for your study purpose.
For limits and liability, see the Terms of Use and Privacy Policy.
National datasets already exist. SWAT+ already exists. The missing layer is a reliable system that connects those resources into usable watershed model packages at scale.
SWATGenX is that layer: turning public environmental data into inspectable, downloadable, high-resolution SWAT+ setups.
SWATGenX is an independent platform. It has no affiliation with, and no ties to, any university, research institution, national laboratory, government agency, or company. There is no parent organization, no institutional sponsor, and no co-developer or partner organization of any kind.
It is built and maintained by one person — Vahid Rafiei, a computational hydrologist, who founded, designed, and continues to develop it as the sole developer, drawing on years of work in hydrologic and water-quality modeling, PFAS fate and transport, groundwater–surface water interaction, agricultural water management, and environmental software development. It is modeling infrastructure—not a generic mapping app.
Scientific papers cited across this site are cited as literature. A citation is not an affiliation, an endorsement, or a partnership, and neither the platform nor its founder is presented here as representing any institution.
The platform's coupled SWAT+/MODFLOW 6 engine connects surface water and groundwater, and its research build simulates PFAS fate and transport end-to-end — soil sorption, aquifer transport, and groundwater-to-stream discharge — demonstrated at AFFF-impacted sites (see the SWAT+MODFLOW-6 page under Research).
The methods behind the platform are documented in a growing body of research — automated high-resolution SWAT+ model generation, the two-way coupled SWAT+/MODFLOW 6 groundwater pathway, engine acceleration, and national data inventories of well lithology, aquifer hydraulics, and soil PFAS. See the publications for the current record.
Founded and developed by Vahid Rafiei (ORCID). Questions or partnerships: LinkedIn or info@swatgenx.com.
Page updated 2026-05-07.