HEC-RAS
FreeVerified
The world's most used hydraulic model: free 1D/2D river analysis, sediment, water quality and flood mapping.
Hydraulics & River SystemsActiveRiver Modelling2D Hydraulic Modelling
Flood Modeller
ActiveJacobs' 1D/2D river and floodplain suite — a UK practice staple with a genuinely useful free tier.
by Jacobs
- Pricing
- Freemium
- License
- Proprietary
- Commercial use
- Permitted
- Ecosystem
- Standalone, Python API
- Platform
- Windows
About Flood Modeller
Flood Modeller (formerly ISIS) is Jacobs' river modelling suite: a mature 1D solver with a deep structure library, fast 2D engines (including GPU), and coupling to TUFLOW and estuary tools. Alongside TUFLOW it is one of the two engines UK flood-risk practice standardised on, and its 1D solver still handles long networks of hydraulic structures exceptionally well.
Uniquely among commercial river packages it ships a free tier (limited node count) that is genuinely usable for small schemes and learning — a sensible on-ramp before committing to a licence.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
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