HEC-RAS is a public domain hydraulic modelling software application developed by the U.S. Army Corps of Engineers Hydrologic Engineering Centre. Following are some downloads and links relevant to HEC-RAS 5.0 and comparisons to other 2D models:

Since the last official release of HEC-RAS 4.1 over five years ago, the U.S. Army Corps of Engineers’ Hydrologic Engineering Centre has been integrating 2-dimensional flow, unsteady sediment transport, and other new capabilities into the newly released Version 5.0. New features in HEC-RAS 5.0 include:

  • Two-dimensional and combined one- and two-dimensional unsteady flow modelling
  • New HEC-RAS Mapper capabilities and enhancements
  • Automated Manning’s n value calibration for one-dimensional unsteady flow
  • Simplified physical breaching algorithm for dams and levees
  • Breach width and development time calculator
  • New hydraulic outlet features for inline structures
  • Sediment transport modelling enhancements, including reservoir flushing and sluicing, as well as channel stability using BSTEM integrated within HEC-RAS
  • Water quality modelling enhancements
  • New 2D user’s manual
  • New example applications
  • Updated reference manuals and help systems
  • Numerous bug fixes
  • Increased flexibility in defining and modifying 2D meshes via user-defined break lines
  • Georeferencing of lateral structures for combined 1D-2D connections
  • 2D rain-on-grid with precipitation boundary conditions
  • TIN-based sloping water surface technique to show spatial results inside of RAS Mapper
  • More flexible internal hydraulic structures
  • Improvements to the stability of connecting 1D reaches into and out of 2D flow areas
  • Unsteady sediment transport

For more details, see What’s New in HEC-RAS and this LinkedIn post by David Markwood. Here’s a piece about the history of HEC-RAS.

Here are some instructional videos and tutorials online:

        • Why hydraulic modelling? (Love this one…especially since I’ve been using the alluvial fans on Mars in my lectures for years now)

        • Newberry’s introduction to 2D modelling

        • Basic tutorial on setting up a HEC-RAS model by Mr. Isaac Wait

        • HEC-GeoRAS floodplain mapping tutorial by Mr. Yassir Abduljaleel

        • Example of a coupled 1D-2D HEC-RAS model by Marton



Training Services

Register your interest for open or in-house course in your area in 2018! Learn what's new in HEC-RAS 5.0.4 and get started with our Introductory Workshop document. Who attends our courses?  What are they saying?

Consulting Services

Need help setting up, reviewing, or troubleshooting models? We also offer drainage designs, surface water management plans, QA/QC, and more. See our consulting services or book in customised, in-house training.

Links and Downloads

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