HEC-RAS 6.7 Beta 4

lug 23, 2025

🚀 HEC‑RAS 6.7 Beta 4 – What’s New?

Automatically detects modern CPUs with hybrid cores and optimizes usage of performance (“p‑cores”) over efficiency (“e‑cores”) during 2D simulations, offering faster run times. Users can review or enforce settings via Options → Program Setup → Parallelization / CPU Affinity

A new experimental module models secondary (helical) currents in river bends using both equilibrium and non-equilibrium shallow-water methods, closely mirroring Delft3D evaluations, enhancing realism in 2D bend simulations

Streamlined Profile Plots: Now include hydraulic structure profiles (e.g., bridges, culverts) overlaid on the water surface, simplifying interpretation HEC.
Improved Time-Series Hydrographs: Users can now select from a table listing 2D Connections, bridges, reference lines, etc., making exploration of multiple hydrographs more efficient

USGS Terrain Download Tool: Corrected failures when selecting “all” data sources; added ability to filter by individual resolutions
Volume Accounting: Adjusted misreports in scenarios combining 2D cells with both internal boundary conditions and culverts—results now accurate though previously slightly misquantified
Multiple 2D Bridges Handling: Fixed a mapping error that caused crashes in models with multiple bridges across different flow areas
Pipe Network Stability: Resolved crashes caused by duplicate property entries affecting flat systems; network now computes reliably
Pipe Network Connection: Fixed incorrect pipe-to-surface connectivity in multi-system networks due to indexing flaws
2D Sediment Transport: Re-enabled volume-correction to prevent artificial variations in sediment concentration during wetting and drying cycles
NLD Shapefile Download: Restored functionality in national land data downloads, which had been failing due to upstream format changes

Mesh Export Limits Lifted: Previous restriction on maximum cells per facepoint removed—RAS 6.7 Beta 4 now supports denser 2D meshes

Several experts are already praising Beta 4’s improved plotting and CPU affinity optimizations.
Although pipe-network support debuted earlier, folks on r/HECRAS note some ongoing quirks in hydrograph plotting—Beta 4’s fixes should reduce these issues
The YouTube demo on pipe networks in 6.7 can serve as a helpful walkthrough, even considering the recent fixes

HEC‑RAS 6.7 Beta 4 is a refined release focused on performance, visualization, and stability: