HEC-RAS 6.1 has been released!

Reported problems with previous versions can be seen by choosing the Versions drop down in the upper right corner of this page.


IssueDescriptionStatus 1 2 3 4
Multi-River Riprap 

The River-Reach-RS drop down does not repopulate the correct reaches if a new River is selected


2D Sediment Subcell Elevation Plotting Error in SI Units

The sediment subcell bed elevation plot does not produce correct subcell areas when running in SI units. Spatial maps of bed elevations are correct in both SI and US English unit systems. Only the subcell bed elevation plots are affected. The work around is to convert the project to US English units. 


2D Sediment Consolidation with Morphologic Acceleration

The morphologic acceleration was not being considered in the calculation of consolidation. Therefore, Morphologic Acceleration Factor values other than 1.0 do not yield correct results. The work around is to use a Morphologic Acceleration Factor of 1.0 when consolidation is needed. 


1D Bridges being assigned wrong River after saving in RAS Mapper

If the model contains river reaches with the same name, For example: River A, Reach A; and River B, Reach A, a 1D bridge may be assigned the wrong river after saving in RAS Mapper.  Work-around is to not have reaches with the same name


Unhandled Exception Saving Geometry in RAS Mapper

If the model contains interpolated cross sections and 1D bridges, then there is a chance an unhandled exception will occur in RAS Mapper on save.  Work-around is to remove all *'s from the RiverStationName column for cross-sections. 


Precipitation Ratio Not Being Applied

The optional precipitation ratio specified in the Unsteady Flow Data editor is not being applied. The only work around is to modify the precipitation data directly. 


Boundary Condition Line Incorrectly Assigning Storage Area/2D Area. 

Sometimes adding a boundary condition line using RAS Mapper will assign the wrong Storage Area or the wrong 2D area.  The ability to reassign with a right click menu will be added for version 6.2.  To assign a boundary condition line to a different Storage Area or 2D Area, follow these steps:

  1. Start editing the geometry
  2. Click and drag the line so it is closer to the perimeter of the intended 2D area/ Storage area
  3. Double click the line to open it for editing
  4. Add a point to the line
  5. Ctrl+Z or click undo to undo adding the point to the line
  6. Double click to close the line.  At this point the BC line will reassign itself, hopefully it assigns to the intended 2D area/Storage Area
  7. Ctrl+Z to undo moving the line, this undos the movement done in step 2.
  8. Stop editing and save if the boundary condition line is assigned properly.


Riprap Calculator Lagged XS update

If you change the Reference XS in the riprap calculator it does not update the hydraulics until something else in the editor is changed.

Work around: When you update the reference XS in the riprap calculator, change something else (and then change it back) to get the hydraulics to update.  This has been fixed for version 6.2.


Sanitize Infiltration Classification Names CrashAttempting to sanitize an infiltration layer will cause RAS Mapper to crash.  For now sanitize the dependency layers, such as soils and landcover individually


Computing Face Profiles Slow With Polygon Mods With Control Points

Some users are reporting longer than usual times for computing face profiles when their terrain has polygon modifications with control points.  A possible work around is:

For each polygon mod:

    clip the terrain using the steps described here

    The clipped terrain will have the same terrain mods as the source terrain.  The clip routine works on terrain tiles, a terrain tile may contain more than just the one polygon mod.  Remove mods that are outside the tile.

    Resample the clipped terrain to a single terrain so the mod gets burned into the terrain.

Remake the original terrain, using the new layers from clipping each polygon mod as inputs for the new RAS terrain.

At this point, your terrain should look the same as before, but not have any polygon modifications in it.  This will make RAS use the standard rasterized terrain approach for computing face profiles.


Sediment Routing Method Connected to the Classic Output SelectionIf you select the "Limit to Water Velocity" method in 1D sediment routing it will only work if you also have the "Classic Output" file selected.  The Classic Output is large and redundant with information in the sediment HDF 5 file.  So some sediment modelers choose to turn it off. But these features got tied together.  So in 6.1, if you want to limit the sediment velocity to the water velocity, you will have to "Write Classic Output (WSE Profile)


Quasi-Unsteady Uniform Lateral Inflow Across StructuresHEC-RAS does not compute the reach lengths correctly to weight the uniform lateral flows in Quasi-Unsteady if there is a structure in the sub-reach.  It can compute an inflow that does not sum to the user specified inflow over all cross sections.  And if there is a sediment rating curve attached, it does not always bring in the expected sediment (since sediment load is function of flow).  This was fixed for 6.2.


Flow Optimization table not showingThe Flow Optimization table is not showing the proper information for the selected structure type.  Junctions are always on top.


2D Sediment Computation MultiplierThe sediment computation multiplier does not work for 2D sediment. There is no workaround for the bug. 


Default line styles not applying/saving in Hydrograph plot.Changing the default line styles in the "Lines and Symbols Editor" by right clicking a plot will not change associated lines to that style, and changes will not be saved.  The only workaround at the moment is view the results in version 6.0 hydrograph plotter.


Datasets containing gates will cause the Hydrograph plot to crash if more than one plan is selected.Trying to open 2 plans at once for a dataset with gates will cause the plotter to crash.  The only workaround at the moment is view the results in the version 6.0 hydrograph plotter.


Datasets containing gates will sometimes not plot in Hydrograph Plot

After an unsteady run, and trying to open the hydrograph plotter, the hydrograph plotter may show an error box "Sequence has no elements."  The hydrograph plotter will open correctly if the user clicks the hydrograph plot button again. 


RipRap calculator not loading with unsteady datasets

The riprap calculator will not launch when a project with a project with unsteady data is loaded. Launch it with a steady dataset or with no dataset at all (to run it headless).


3D Viewer not launching from main RAS window

The 3D Viewer will no longer launch from HEC-RAS main window.  Can launch 3D Viewer from RAS Mapper. Details on launching the 3D Viewer are here.


Renaming a 2D area in RAS Mapper Breaks the Connection with Boundary Conditions Lines

If a 2D area is renamed in RAS Mapper, the boundary conditions for the 2D area are lost and the user has to reenter the boundary conditions in the Unsteady Flow Data editor.


Coupled 1D/2D Sediment Simulations

It is not possible to run coupled 1D/2D sediment simulations. However, a possible work around which may feasible in some situations is to run 1D and 2D sediment decoupled. For example, a 1D sediment model can be run and used to specify sediment time series for a downstream 2D sediment model. 


Unable to plot Initial Condition Points

Initial Condition Points will show "No Data for Plot" in the new Hydrograph Plotter.  Work around is make an identical reference point at the initial condition point and plot that instead.


General non-English Language issues

"Error in Loading Geometry Data" in the Geometry Schematic.

GDAL Conflict when Opening RAS Mapper

"Error initializing the GDAL path variables. Please check HEC-RAS installation" error message is displayed when attempting to open RAS Mapper.

1 RESOLVED - issue is fixed and will be available in the next release.
2 IN PROGRESS - issue identified is currently being worked on.
3 IMPROVED - this next version includes an incremental improvement but not a total fix.
4 FUTURE VERSION - this requires a structural change or major development.  The team will add it to a future version if funding permits.