HEC-HMS
FreeVerified
The US Army Corps standard for rainfall-runoff modelling — event and continuous simulation, free to use.
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PRMS
ActiveUSGS Precipitation-Runoff Modeling System — distributed continuous simulation with strong snow physics.
by US Geological Survey
- Pricing
- Gov-Public
- License
- US Government (public domain)
- Commercial use
- Permitted
- Ecosystem
- Fortran, Python
- Platform
- Windows, macOS, Linux
About PRMS
PRMS (Precipitation-Runoff Modeling System) is the USGS's deterministic, distributed-parameter watershed model. It simulates the full land-surface water balance — interception, snowpack accumulation and melt, soil-zone storage, groundwater flow and runoff — on hydrologic response units, over decades of daily record.
PRMS is a natural fit for water-supply and climate-change studies in snow-influenced basins, and it couples with MODFLOW as GSFLOW for integrated surface-groundwater simulation. It is public domain, scriptable, and supported by USGS national parameter datasets in the US.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
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