HEC-RAS
FreeVerified
The world's most used hydraulic model: free 1D/2D river analysis, sediment, water quality and flood mapping.
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
Appears in collections
- Alternatives to HEC-RAS
Free and commercial hydraulic engines worth knowing when HEC-RAS is not the answer.
Alternatives to Flood Modeller
Ranked by the topics, categories and workflow stages they share with Flood Modeller.
RIVIA
Open Source
A modern Python interface for HEC-RAS project parsing, simulation automation, and result visualization.
TUFLOW
Commercial
Benchmark-setting commercial 1D/2D flood engine with GPU acceleration — dominant in AU/UK flood studies.
MIKE+
Commercial
DHI's unified platform for rivers, urban drainage and distribution networks — successor to MIKE 11/MIKE URBAN.
BASEMENT
Free
ETH Zurich's free 2D hydraulics and morphodynamics simulator — rivers, sediment and hazard mapping.
Delft3D FM
Open Source
Deltares' open flexible-mesh suite for rivers, estuaries and coasts — hydrodynamics to morphology.