The following is a list of the major new features that have been added to HEC-RAS 6.0 since version 5.0.7.  Many additional minor features/upgrades have also been made to the software.

  1. Spatial Precipitation and Infiltration for 2D, SA, and XS.  We have added the ability to make use of spatially and time varying precipitation and infiltration to 2D flow Areas, Storage areas, and between 1D cross sections.  We are using three infiltration methods, two that are simple (Initial and Constant Loss method and the SCS method), and one more detailed method (Green and Ampt method).
  2. Bridge Hydraulics inside of 2D Flow Areas.  This option allows users to lay out a bridge inside of a 2D Flow Area.  The bridge’s hydraulic properties are processed into a family of curves, just like in 1D.  This family of curves will be used to compute the forces due to the bridge based on the flow through the bridge opening, as well as flow over top of the bridge.  These forces are then applied to a special version of the 2D momentum equation across the faces that make up the centerline of the bridge.
  3. HEC-RAS Mapper - Editing Tools.  We have finished all the editing tools for structures, extracting n values for 1D cross sections, ineffective flow areas, blocked obstructions, and XS high ground option in RAS Mapper.  HEC-GeoRAS is no longer needed for creating HEC-RAS models.
  4. 1D Finite Volume Solver.  We have added a 1D Finite volume solver.  This will be optional to turn on, as the default will still be the 1D Finite Difference solver for compatibility with previously developed models.  This method allows for 1D channels to start out dry or go dry during the simulation.  This new solver is a more stable solution scheme than the current 1D finite difference scheme, especially for steep streams and modeling very low flows.
  5. Wind forces to HEC-RAS 1D and 2D.  We have added wind forces to both 1D and 2D modeling in HEC-RAS. This will require either gaged wind speed and direction data, or gridded wind speed and direction data.  When gaged data are entered, an interpolation algorithm is used for the speed and the direction.  When gridded data are used, the program uses the cross sections and cell centers to get the speed and direction from the gridded data.
  6. Computational Speed Improvements for 2D.  We have improved the computational speed by further parallelizing the 2D code.  2D models should be at least 20 to 50% faster than the previous version.
  7. DSS7 – We are using a new version of DSS (DSS7). The new DSS7 libraries allow for: larger files sizes; faster reads/writes; smaller time steps (can go down to a 1-second time step for DSS Hydrographs.  The current DSS6 is limited to a 1-minute time step).
  8. Enhancements to Pump Stations in 2D Areas. The program now allows pumps to be connected to 2D areas by specifying an X and Y coordinate for the “To” and “From” location of a pump.  Now pumps can be connected to 2D areas, 1D cross sections, and Storage Areas in any combination.
  9. New Breach Time Series Plot.  We add a new time series plot that has three graphic windows all on the same plot.  The top graphic is the headwater and tail water surface elevations vs time.  The middle plot is the velocity through the breach vs time.  And the bottom plot is the breach width and depth vs time.  Final specifications for the new breach plot were based on MMC requirements.
  10. New Hydrograph Plotter. We have redesigned the hydrograph plotter, to be compatible with the new DSS7 file formats.  The new plotter still plots all the same information as before, but with a new look and feel.
  11. Physically Based Breaching Option: We added a third breaching option for Dams and Levees. This is a true physics-based breaching method based on Dr. Wue’s DLBreach program.
  12. 3D Graphics/Animations:  We added a true 3D viewer option.  Users will be able to visualize the terrain and water in 3D.  The water can be animated in time.  Users can fly around the model to have different views of the system in 3D.
  13. HEC-RAS Mapper - Raster Calculator. A Raster Calculator has been added to RAS Mapper in order to allow users to make their own mapper layers through mathematical computations of existing map layers.
  14.  HEC-RAS Mapper - Terrain Modification Tools. This option allows users to modify terrain with lines and polygons, as well as specific options for channels and levees.  Additionally, generic shapes, like circles and rectangles have also be added.  Users will also have options for removing terrain (i.e. existing levees). 
  15. HEC-RAS Mapper - Improvements to Grid/Mesh Generation Tools. We have made improvements to the Breaklines and Refinement Regions meshing tools.  They do a better job at not deleting cells around nearby breaklines and mesh refinement regions.
  16. Initial Conditions for 2D Areas. Currently, defining initial conditions inside of 2D areas is very limiting.  Initial conditions can be dry, a single elevation, or set using a restart file from a previous run.  We have added an option where you can use output for a date/time from any plan in the model that has already been run.  This works even if your current plan has different geometry features.
  17. Iterative Matrix Solvers. We have added new matrix solvers for 2D that can potentially speed up the computations.  They are optional, as they can potentially cause model instability in some cases.
  18. New SWE 2D solver in HEC-RAS. We have added a third equation solver for 2D modeling in HEC-RAS.  This third solver is a full shallow water equation solver but does a better job at conserving momentum than our current SWE solver.  The new method is an explicit solver and requires smaller time steps, therefore it takes longer to run in many cases.
  19. New turbulence methods. We added a new and more robust turbulence modeling options for 2D modeling with the full Shallow Water equations.
  20. Remove Dummy Cells Around 2D Outer Boundary. In version 5.0.7, the 2D mesh has dummy cells around the entire 2D outer boundary.  This unnecessary adds to the computational time and memory usage.  We have removed all of them from the matrix solution, and then only use these dummy cells where there are external boundary conditions.  This has improved the speed of the code and reduced the memory footprint.
  21. Non-Newtonian fluids option for 1D and 2D. Mud and Debris flows capabilities have been added to both 1D modeling and 2D modeling in HEC-RAS.
  22. 2D Sediment Transport Computations. We have added the ability to perform full blow sediment transport, erosion and deposition modeling to the 2D solver in HEC-RAS.
  23. New 1D Sediment Features. There are many new 1D sediment features that have been added to HEC-RAS (see the list here).
  24. Water Quality Computations. There are new water quality features that have been added to HEC-RAS.
  25. New Debug Report Zip File Option. We have updated the option that allows user to create what we call a “Debug Report” zip file.  When selecting this option from the File menu of the main RAS window, users will now be able to attach the terrain, Manning’s n layers, etc… into the zip file.