HEC-HMS
FreeVerified
The US Army Corps standard for rainfall-runoff modelling — event and continuous simulation, free to use.
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Raven
ActiveA flexible hydrological modelling framework — emulate GR4J, HBV, HMETS or build your own model structure.
by University of Waterloo
- Pricing
- Open Source
- License
- Artistic License 2.0
- Commercial use
- Permitted
- Ecosystem
- C++, Python
- Platform
- Windows, macOS, Linux
About Raven
Raven, from the University of Waterloo, treats model structure as user input: instead of shipping one fixed conceptual model, it lets you assemble process representations (infiltration, baseflow, snow, routing) into whatever structure the catchment demands — and it ships templates that emulate GR4J, HBV-EC, HMETS, UBCWM and others.
That flexibility makes Raven popular for research and for operational forecasting in Canada, where it drives several flood-forecast systems. It is fast C++ with clean text input, active development and a growing Python ecosystem (RavenPy) for scripted workflows.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
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