ESRI has partnered with CLB Engineering Corporation's William "Bill" Katzenmeyer, Vice President and creator of the RAS Commander Open Source Python Library, to bring powerful HEC-RAS 6.x HDF5 data extraction capabilities directly into ArcGIS Pro through the Arc Hydro Tools framework.
This collaboration represents a groundbreaking application of LLMÂ Forward engineeringâusing Large Language Models to rapidly develop sophisticated geospatial tools that bridge hydraulic modeling and GIS workflows.
Following an ASFPM brainstorming session in late May 2025, this toolbox was developed using CLB's innovative LLM Forward approach, achieving productionâready functionality in just over a monthâdemonstrating the transformative potential of AIâassisted development in the waterâresources sector.
RAS Commander Arc Hydro Tools enables hydraulic engineers and GIS professionals to seamlessly extract and visualize HECâRAS 1D and 2D geometry, terrain, and results data without manual conversion steps. This free and openâsource toolbox brings the power of the RAS Commander library directly into ArcGIS Pro.
- đ Direct HDF5 Import â Load HECâRAS data directly from geometry (
g*.hdf
) and plan (p*.hdf
) files - đşď¸ 1D Geometry Support â Extract cross sections, river centerlines, bank lines, and structures
- đ 2D Geometry Support â Import mesh elements, breaklines, boundary conditions, and cell polygons
- đď¸ Pipe Networks â Full support for storm/sewer pipe networks including SWMM imports
- đ Results Visualization â Display maximum WSE and velocity results with time of occurrence
- â°ď¸ Terrain Loading â Import HECâRAS terrain layers from RAS Mapper VRT files
- đď¸ Project Organization â Batch process entire HECâRAS projects into organized geodatabases

Developed by CLB Engineering in partnership with ESRI
The RAS Commander toolbox will be included as part of the Arc Hydro Tools distribution. This is the recommended installation method for most users.
-
Install Arc Hydro Tools with the Arc Hydro installer
-
If you are updating, uninstall Arc Hydro and re-install the latest version (Version 3.4.30 minimum)
-
The RASÂ Commander toolbox will be available under:
Toolboxes â Arc Hydro Tools â RAS Commander
Note that these toolboxes have only been tested in ArcGIS, not the older ArcMap.
Development install is detailed further in case you want to edit the tools or extend them, or get the latest bleeding-edge version between Arc Hydro updates.
Below are highâresolution screenshots of each Arc Hydro tool in action to help you get up to speed quickly.
These images showcase a 2D HECâRAS model of the New Orleans metro stormâwater system, complete with pipe networks, mesh polygons, and a maximum WSEL raster generated directly inside ArcGIS Pro.
This is a communityâdriven effort, and we're actively seeking your feedback!
- đď¸ Municipality looking to integrate HECâRAS data into dashboards?
- đˇ Engineer communicating multiâhazard flood risk?
- đşď¸ GIS Professional preparing 2D model data?
- đŹ Researcher analyzing model results?
We want to hear from you! Share your ideas and use cases
This project showcases CLBÂ Engineering's LLMÂ Forward approachâa revolutionary methodology that leverages Large Language Models to accelerate software development while maintaining professionalâgrade quality. Learn more about this innovative approach and the author's work at Engineering with LLMs.
- Rapid Development: From concept to production in just over a month
- CrossâDomain Expertise: Seamlessly bridges hydraulic engineering and GIS
- Community Focused: Built with user feedback at its core
- Open Source: Transparent development process you can contribute to
For developers and users who want to extend or customize the tools:
-
Clone the Repository
git clone https://github.com/gpt-cmdr/ras-commander-hydro.git cd ras-commander-hydro
-
Option A: Add Toolbox in ArcGIS Pro
- Open ArcGISÂ Pro
- In the Catalog pane, rightâclick on Toolboxes
- Select Add Toolbox
- Navigate to
toolboxes/RAS-Commander.pyt
-
Option B: Install for Development (Requires Admin)
# Run PowerShell as Administrator cd Resources .\install_toolbox.ps1
To uninstall:
# Run PowerShell as Administrator cd Resources .\uninstall_toolbox.ps1
Extract comprehensive 1D hydraulic model elements for report figures and analysis.
Import complete 2D model components including mesh cells as polygons for advanced spatial analysis.
Visualize maximum waterâsurface elevation and velocity results with temporal data.
Import terrain layers from RASÂ Mapper with proper georeferencing.
Comprehensive batchâprocessing tool for entire HECâRAS projects.
- â  1D and 2D Geometry Extraction (Including Pipe Networks!)
- â  Max WSE and Velocity as 2D Mesh Results
- â Â Terrain Import for Inundation Mapping
- â Â Support for HECâRASÂ 2D Models
- â Â Organize Entire Projects as Geodatabases
- đ Improved Schemas & Layer Styling
- đ 1D Results & Full Time Series
- đ Fluvial/Pluvial Delineation
- đ Land Use Layer Integration
- đ Sync Changes Back to HECâRAS
- đŻ CommunityâRequested Features
View Full Roadmap &Â Vote on Features
Join us for an inâdepth webinar showcasing advanced workflows and new features.
Visit our GitHub Repository to:
- Report issues
- Suggest features
- Submit pull requests
- Share your use cases
- RAS Commander Arc Hydro Tools: https://github.com/gpt-cmdr/ras-commander-hydro
- RASÂ Commander Library: https://github.com/gpt-cmdr/ras-commander
- CLBÂ Engineering Corporation: https://clbengineering.com/
- Engineering with LLMs: https://engineeringwithllms.info/
This project is licensed under the MITÂ License â see the LICENSE file for details.
- ESRI â Partnership and Arc Hydro Tools integration
- CLBÂ Engineering â Project sponsor and LLMÂ Forward methodology
- USACE HEC â HECâRAS software and Example Projects
- Water Resources Community â For invaluable feedback and use cases