SWAT
Texas A&M AgriLife / USDA-ARS
SWAT simulates what happens across a whole watershed over decades: rainfall and evapotranspiration, surface runoff and baseflow, soil erosion, and the transport of nitrogen, phosphorus and pesticides from field to stream. The basin is divided into hydrologic response units combining soil, slope and land use.
It answers questions a single-event simulation cannot: what converting farmland to housing does to stream water quality, how a change in fertiliser affects nitrogen load, and what each source contributes to pollution.
Distributed free with source code, and used together with QGIS or ArcGIS through dedicated interfaces. Its data and parameters are calibrated to American conditions — adapt to local climate and soils.
Ratings & Reviews
| Licence type | Completely Free, Open Source |
|---|---|
| Licence terms | Free academic and government software with open source code, at no cost. Built around American data and conditions — calibrate to local conditions. |
| Platforms | Windows |
| Engineering field | Civil Engineering, Environmental & Water |
| Tool type | Hydrology & Drainage, Simulation & FEA |
| Vendor site | swat.tamu.edu |
This link goes to the vendor site. EngiFree hosts no installers and distributes no cracked versions.
Last verified: 2026-09-07
