SWATGenXSWATGenX
Continental U.S. · NHDPlus HR

Watershed modeling for every river in the continental U.S.

SWAT+ models for any river in the lower 48 states, with MODFLOW 6 groundwater models and cloud calibration against USGS streamflow and groundwater heads. Built for consultancies, utilities, and agencies.

Every model is built from the public data and standard engines a reviewer will ask about:

  • USGS NWIS
  • NHDPlus HR
  • WBD
  • gSSURGO
  • NLCD/CDL
  • PRISM
  • NSRDB
  • SWAT+
  • QSWAT+
  • SWAT+ Editor
  • MODFLOW 6
  • Flopy
  • GDAL
  • SGX3D
  • AWS

SWATGenX changes where you start. Choose a stream gauge or a watershed anywhere in the lower forty-eight states, and we build a complete, ready-to-run SWAT+ model for it from national data, usually within a couple of hours.

Capability tour

Eight pillars of SWATGenX

All eight ship in one watershed workflow and one portable SWAT+ project.

01 · National groundwater inventory

The national well inventory — collected and harmonized.

State agency well logs, interval-by-interval — searchable, mappable, and ready for MODFLOW 6 setup.

Explore groundwater data →

02 · National PFAS data moat

Harmonized monitoring, soil profiles, and screened facilities — live counts load from the inventories.

Water, groundwater, soil, and tissue measurements from public agency records — joined with depth-resolved soil reports, potential-source screening, and PFAS litigation dockets for site context.

See the full PFAS data holding →

03 · HUC8 → HUC12 → HUC14

Model the reach you study, not the whole basin above it.

The Peace River basin, Florida: HUC12 unit outlines and channels, with a smaller nested watershed outlined inside it

Model at a USGS gauge, a HUC12 outlet, or single HUC14 catchments you pick, with everything upstream if you choose.

See nested modeling →

04 · SWAT+ / MODFLOW 6

SWAT+ with a MODFLOW 6 groundwater model, built automatically.

A SWAT+ with MODFLOW order adds a steady-state MODFLOW 6 groundwater model, designed to take its recharge from SWAT+ (until that link is finished, a uniform default of about 200 mm/yr). Daily two-way coupling via BMI/XMI is research work. Inspect the models in 3D.

See coupled modeling →

05 · PFAS fate and transport

PFAS from soil to aquifer to streams in SWAT+/MODFLOW 6 (research).

  • Delivered: SWAT+ model; a SWAT+ with MODFLOW order adds a steady-state MODFLOW 6 model, side by side, not coupled.
  • Engine: SWAT+ ↔ MODFLOW 6 daily, in one process (recharge down, stream–aquifer exchange both ways); water-balance fix in progress.
  • Engine: PFAS in soil, streams, the vadose zone and groundwater.
  • Not coupled: lakes and wetlands ↔ aquifer (routed in SWAT+ only); land → vadose zone (SWAT+ percolation feeds the vadose model offline).
The full table →

06 · Public MCP server

MCP tools for Claude and Cursor.

Once you sign in: search models, query groundwater and PFAS inventories, preview builds — and, with your account, order and download SWAT+ packages.

See how to connect →

07 · Open parallel SWAT+ engine

Byte-identical parallel SWAT+ for HRUs and streams.

OpenMP wavefront on HRUs and channel routing. Byte-identical to serial on five basins at 1–16 threads with routing serial, and in both modes at 2–8 threads in the ship gate (v1.0-49); about five times faster at 16 threads on Peace River.

See engine benchmarks →

08 · Automated cloud calibration

Fully optimized MMPSO calibration on dedicated AWS.

Calibrate SWAT+ against USGS streamflow on per-job EC2 instances — parallel MMPSO, live progress on the dashboard, charged at standard AWS rates.

See cloud calibration →

Watershed science, end to end

One platform — from national inventories through coupled models, cloud calibration, and a parallel engine.

Explore the public data. Connect Claude or Cursor over MCP. Create an account when you order a SWAT+ package.

Need larger allocations, coupling, or calibration? See access levels.

Appropriate use

Flood and rainfall indicators on SWATGenX are for rapid triage and planning context, not a substitute for site-specific hydraulic studies, FEMA flood insurance studies, or official emergency warnings. For methodology and citations see Data & methodology. Account rules and data practices are in the Terms of Use and Privacy Policy.