Causeway Flow
Commercial
Storm and foul water drainage design and 1D hydraulic modelling software for UK and Irish civil engineers.
LocalSWMM
ActiveBrowser-based urban stormwater and drainage modeling powered by OpenSWMM 6 compiled to WebAssembly.
by Joaquín Alvarado
- Pricing
- Open Source
- License
- MIT
- Commercial use
- Permitted
- Ecosystem
- C++, WebAssembly, JavaScript
- Platform
- Web Browser
About LocalSWMM
LocalSWMM is a WebAssembly port of OpenSWMM 6 that runs dynamic urban drainage simulations directly in the web browser. The tool executes the modernized C++ SWMM 6 engine client-side without sending model files or simulation data to external servers, enabling fast execution and complete data privacy.
Engineers reach for LocalSWMM to perform rapid stormwater calculations, inspect SWMM input files, or run dynamic sewer and drainage models without installing desktop software. A practical caveat is that large urban networks or complex 2D surface models may run slower or hit browser memory limits compared to native desktop executables.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
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