HEC-RAS Changelog

What's new in HEC-RAS 6.5 Beta

Nov 9, 2023

Major issues:
Sediment Rating Curve Calculator Does not Update Annual Load
Sediment Rating Curve Calculator is Unit Naïve
Floodway Encroachments - Blocked Culverts
Floodway Encroachments
Pump - Advanced Control Rules not saving if editing in RAS Mapper
Pump - The total number of Pumping Stations limited to 20
Hydraulic structures in 2D not checking hydraulic connectivity between cells connected to structure
Culvert Barrels / Gate Openings - not saving alignment in RAS Mapper
Re-compute of property tables for 2D Area when updating 2D Connections
Minor Issues:
Fixed total gate flow over-summing flows from each gate when there were more than 10 gate openings in
the Hydrograph plotter.
Fixed profile plots not reloading when a result updates.
Importing a Sediment File into a New Project generates a "Path/File access error."
Fixed a crash when viewing cross sections in the property table plot.
Fixed Mannings n property tables computes from crashing due to too n many discretizations per face.
Fixed the measure line right click menu sometimes taking a long time show.
Fixed being unable to create a calculated layer if there were no results.
Fixed USGS downloads with many files selected taking a while to start downloading.
The Rating Curve Calculator assumes US Customary Units. This means the labels are wrong and the
Load<-->Concentration conversion is incorrect if users import SI data. If users are importing data from the
USGS database, this is not an issue, because the tool imports in US Customary. But if users import their
own data (through the clipboard) this labels and the concentration conversion will be wrong.
Percent Time Inundated Map Layer legend now shows units of percent, not hours.
The Average Annual Load value in the sediment rating curve did not update in version 6.4 and 6.4.1 when
users changed their rating curve assumptions. This has been fixed.
Fixed culvert, gate, time series outlet and rating curve outlet changes not saving correctly after changes
were made.
Fixed floodplain being completely filled in for cross sections that had empty rows in unsteady
encroachment table.
Fixed RAS Mapper panning when it should bring up a menu while editing.
Fixed Histogram crashing when the map's min value is equal to the max value.
Recomputing 2D meshes in RAS Mapper will now throw an error if a cell has less than 3 faces.
Fixed having to recompute property tables if non-mesh geometric elements were changed.
HEC-RAS Release Notes – 8
Fixed "Edit 2D Connection Breakline Properties" in RAS Mapper taking a long time to show

New in HEC-RAS 6.0.0 Beta (Dec 17, 2020)

New Features:
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.
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).
1D Bridge Hydraulics inside of 2D Flow Areas. This option allows users to lay out a bridge inside of a 2D Flow Area. The bridge is processed into a Family of Curves, just like it does 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.
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
1D Finite Volume Solver. We have added a 1D Finite volume solver. This is optional to turn on, as the default is 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.
Wind forces to HEC-RAS 1D and 2D. We have added wind forces to both 1D and 2D modeling in HEC-RAS. This requires 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, RAS uses the cross section and cell centers to get the speed and direction from the gridded data.
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).
Enhancements to Pump Stations in 2D Areas. We now allow pumps to be connected to 2D areas by specifying an X and Y coordinate for the “To” and “From” location of a pump. Pumps can be connected to 2D areas, 1D cross sections, and Storage Areas in any combination.
New Breach Time Series Plot. A new time series plot that has three graphic windows all on the same plot has been added. The top graphic is the head water and tail water surface elevations vs time. The middle plot is the velocity through the breach vs time. The bottom plot is the breach width and depth vs time. Final specs for this are based on MMC requirements.
New Hydrograph Plotter. We have redone the hydrograph plotter. This was necessary to be compatible with the new DSS7 file formats. The new plotter still plots all of the same information as before, but with a new look and feel.
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.
3D Graphics/Animations: HEC-RAS has a new 3D viewer option. Users are 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.
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.
HEC-RAS Mapper - Terrain Modification Tools. This option allows users to modify terrain elevation values (raise, lower, replace) with lines and polygons, as well as specific options for channels and levees. Additionally, generic shapes, like circles and rectangles have also be added.
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.
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 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 is already been run. This works even if your current plan has different geometry features.
Iterative Matrix Solvers. These are new matrix solvers for 2D that can potentially speed up the computations. They will be optional, as they can potentially cause model instability in some cases.
New SWE 2D solver in HEC-RAS. We have adde 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, so it takes longer to run in many cases.
New turbulence methods. We added a new and more robust turbulence modeling options for 2D modeling with the full Shallow Water equations.
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.
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.
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.
New 1D Sediment Features. There are many new 1D sediment features that have been added to HEC-RAS.
Water Quality Computations. There are new water quality features that have been added to HEC-RAS.
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.
Bug Fixes:
The following is a list of bugs that were found in HEC-RAS Version 5.0.7 and fixed for Version 6.0:
Pilot Channel through Bridges. If you used the Pilot channel option all the way through a bridge and were also using the Pressure and Weir flow option for high flow at the bridge, the program was using the wrong elevation for checking for pressure flow. The results were the program could go into a pressure/weir flow calculation sooner than it should have.
SA/2D Area Conn and Rating Curve. If you were running the model in metric units, and were using a rating curve at an SA/2D Area Connection, if you did not put in coordinates for the centerline the program was connecting the rating curve to the wrong cells.
SA/2D Area Connections with Culverts connected to Storage Areas. The interface was allowing SA/2D Area Connections to have culverts that were lower that the bottom of the storage area. This was causing initial conditions problems and model stability problems. The program was using the lowest point in the storage area as the ware surface against the culvert, which then resulted in a flow being computed, that should have been zero. This is now trapped by the software, and the user must raise the culvert above the storage area minimum or lower the storage area minimum below the culvert.
Geospatial Centerlines for Gate Openings. If a user had more than one gate group in a structure (Lateral structure or SA/2D Area Connection), and they put in geospatial coordinates for the centerlines of the gates, the software was blowing up with an "Unresolved Eternal”. The arrays for the geospatial data were not being dimensioned properly. This has been fixed.
User-defined Rules when structure is connected to 2D flow Area. There was a bug when applying Rules for structures connected to 2D Flow Areas. Rules for a SA/2D Hydraulic Connection will work if it is connected to 1D storage areas on both sides. If either, or both, sides are connected to a 2D flow area, the rules will not work.
Volume accounting Error. A bug was fixed in the volume accounting output for version 5.0.6, but this inadvertently caused a bug in the volume accounting for version 5.0.7. If a user has a model with 2D areas and one or more storage areas, but no 1D reaches, the volume accounting fails to account for the final volume left in the storage areas. It shows up as blank and interprets it as zero. This made it appear like there was a large volume error that actually did not exist. This was only a Volume Accounting output problem, not a computational problem.
Bug in Using a Rating Curve for a Gate. If a rating curve was put in for a gate, and the user only put in two values for the rating curve, such as 0.0 and max gate opening. Then if the user was using a time series of gate openings and put the gate at max opening the entire time. The program was not using max gate opening, instead if water surface is below top of gate it is using max water surface to go into the curve with that as gate opening. It should have used the user specified gate opening and just go to curve and use the flow they put in.
1D/2D Lateral structure Connection across a Bridge and using the 2D Equations to compute flow transfer. If a user connected a Lateral structure from a 1D river to a 2D flow area and was using the "Normal 2D equations" for the flow transfer. If there are bridges, the software had a bug in that it was allowing water to leave the 2D area across the lateral structure in the bridge computational zone (Between the two cross sections that bound the bridge). No flow was supposed to go in or out of this region, due to the fact that the 1D bridge/culvert solution cannot change the flow in the middle of the bridge/culvert.
1D/2D Lateral Structure Connection with 2D Equations for Overflow and additional hydraulic outlet (Culvert, gates, rating curve, or time series flow). If the user has a Lateral structure connected to a 2D flow area that contains one of the hydraulic outlet types (culvert, gates, rating curve, or time series of flow), and they selected to use the 2D Equations to compute the overflow, the program was only computing flow through the hydraulic outlet, and not over the weir with the 2D equations. This was being reported as weir flow was being computed, but it was not.
Internal SA/2D Hydraulic Connection issue. After entering a new internal SA/2D Area Conn inside of a 2D area, when trying to run the model it says that the internal structure is "Not connected to any cross section". This was obviously not correct, as it is an internal structure. To fix it the user had to re-select the head water and tailwater connections from the connection drop downs on the SA/2D Hydraulic Connection editor.
Later Inflow not showing up in Unsteady Flow Editor. If a user had a Lateral Inflow Connected to a Storage Area, it was not always showing up in the Unsteady Flow Data editor. This was an issue due to the flow file being used with two different geometries/Plans. When you open the unsteady flow editor there should be a lateral inflow connection to the Storage area. It is not showing up, however it was in the flow file. If you ran the model it actually uses the flow and runs correctly. You just can’t see it in the flow file.
Rating Curves in SA/2D Connections - Metric Units. If you had a metric unit’s data set and you tried to use the Rating curve option in an SA/2D Area Connection, it was not converting any of the stage and flow data to English units for the computation engine.
1D Reach connected to same 2D Area (upstream and downstream). If you had a 1D river reach directly connected to the same 2D Flow Area, both at the upstream end and downstream end, the program was getting confused on what to set for the initial conditions.

New in HEC-RAS 5.0.5 (Jun 14, 2018)

New in HEC-RAS 5.0.4 (May 3, 2018)

New in HEC-RAS 5.0.3 (Apr 6, 2017)

New in HEC-RAS 4.1.0 (Jul 11, 2013)

Version 4.1 of HEC-RAS includes the following new features:
New RAS Mapper Floodplain Delineation Capabilities
Hydrologic Routing Reaches Within an Unsteady Flow Model Run
New Flow Data And Boundary Conditions Editor for Unsteady Flow
Contraction/Expansion losses for Unsteady Flow
Minor Losses for Unsteady Flow
New Junction Hydraulics Option for Unsteady Flow
Groundwater Leakage for Storage Areas
Water Quality Modeling Enhancements
Sediment Transport Modeling Enhancements
User’s Manuals and Help System
The following is a list of bugs that were found in version 4.0 and fixed for
version 4.1
Sediment:
When using the Exner Active method, the time-series external sediment load was being double counted. Exner5 works correctly.
Unsteady (preprocessor bridge/culvert curves):
The GeomPreprocessor was sometimes computing a critical depth that is right at the elevation of the ineffective flow areas when it should be getting a critical depth that is just slightly above the ineffective flow areas. This causes it to have a higher velocity head and a critical energy that is too high. If the pressure/weir solution is below this "incorrect" critical energy, it may be inappropriately discarded. This problem most frequently showed up in a "jump" in the bridge curves where the solution incorrectly goes from pressure/weir to energy only.
Unsteady (Dam/Levee Breach):
There was a bug when the side slopes of a breach (dam or levee) was set to vertical (slope = 0). The post processor was not showing the Q Breach flow and the breach might be lowering the entire weir to the bottom elevation of the breach (instead of just the rectangle).
Unsteady (time slicing):
There was a potential output bug with any data set that had time slicing turned on (either from the time slicing editor or from the hydrograph editor using the max change in hydrograph flow without reducing the time step). This bug caused the DSS output for storage areas and internal boundaries (weirs, gate openings, etc.) to be incorrectly "stretched out" in time.
Steady (Manning’s n):
The weighted Manning's n total was not being computed correctly.
Sediment:
The reported mass capacity was not being computed correctly. For Exner5, the mass capacity was not taking into account any silt or clay sizes. For both Exner5 and the active layer method, the capacity was based on the conditions at the start of the sediment computation interval. The reported capacity over the sediment computation interval (i.e. an average of the capacity at each bed exchange increment). This was only an error for output.
Sediment: One of the options for the Exner Active method is to make the thickness of the active layer equal to d90. The program was only computing this depth at the start of each computation loop--it was not changing the thickness of the active layer during the bed exchange
iterations. This has been changed so that a new d90, and new d90 thickness, is computed at the start of each bed exchange iteration.
Steady:
The cumulative volume amounts were being reset to zero at culverts and inline weirs, this has been fixed.
Steady and Unsteady:
When a storage connector has a culvert that has entirely supercritical flow, a bug could occasionally be triggered that causes RAS to crash.
Steady (Ice):
There was a bug with the ice computations (both for dynamic ice jams and ice cover) that could cause the steady.exe program to lock up. This only happened when a main channel bank station is at the end of a cross section.
Steady (culvert):
For the Conspan culvert, the Manning's n bottom option was being ignored if the depth of fill was set to zero. This has been fixed so that the optional Manning's n of the bottom will be included in the computations even when the bottom fill is set to zero.
Steady (bridge):
For bridges with class B momentum flow, the momentum answer was occasionally being disregarded. This has now been fixed.
Steady and Unsteady (Pump):
At the start of a profile (or start of an unsteady run), when the pump trigger water surface is between the water surface on and water surface off elevation, the pump could be either on or off. The bias-on flag, on the pump editor, allows the user to select whether the pump should on (box checked) or off (box unchecked). There was a bug in version 4.0 that sometimes the pump would incorrectly start out as on, even though the bias-on flag was not checked.
Steady (lateral structure):
The optional angle term for a Hager type of lateral weir was not being used.
Unsteady (storage connectors):
When the water surface for the two connected storage areas were at the exactly the same stage, the program would sometimes crash or go unstable.
Unsteady (time slicing):
The time slicing option would sometimes cause the post processor to crash (the DSS/hydrograph output was ok).
Steady (Ice):
A cross section that has ice and the water surface was above the top of the cross section (the cross section is "extended"), had a bug that could cause the flow area in the overbank to be ignored.
Unsteady (Storage Areas):
The preprocessor could crash with a memory bug if a project had more than 500 storage areas.
Steady (lateral structure):
Multiple cross sections on the tailwater side did not have appropriate run time checking for possible user entered data errors.
Steady (lateral structure):
There was a bug if the user tried to specify cross section intersections on the tailwater side, but not the headwater side (i.e. the head waterside was set to default).
Steady (encroachments):
For the encroachment output tables, the change in water surface elevation just upstream of multiple openings was incorrect.
Unsteady:
The volume accounting (that is reported in the computation log file) was not correct for lateral structures (the sign was reversed). This was causing a larger reported volume error, and percent error, than was actually the case.
Unsteady:
The volume accounting (that is reported in the computation log file) was not correct for groundwater (the sign was reversed). This was causing a larger reported volume error, and percent error, than was actually the case.
Unsteady (advanced rules):
The "fixed gate flow" (for both inline and lateral structures) had a bug that was causing the flow to be ignored when the gate opening was set to zero feet. The fixed flow for the new version is now being used even if the gate opening is set to zero.
Unsteady (advanced rules):
When the advanced rule procedure was getting a simulation value, for instance the current water surface in a storage area, it was not getting the proper value (it was getting an "assumed" value not the final computed value). This would generally only be a minor difference (eg, a few hundredths of a foot).
Unsteady (advanced rules):
For inline structures, the advanced rules (such as flow minimum) was not working correctly for negative (ie, reverse) flow.
Unsteady (advanced rules):
For advanced rules for a lateral structure, the "structure flow additional" was not actually being added in to the flow.
GeomPreprocessor (multiple opening):
The geometric preprocessor had a bug that could cause an unrealistically high critical depth. This would then cause the in ternal boundary curves to be too high and the unsteady water surf ace results to be too high.
Steady (Froude number):
The alpha velocity coefficient was added to the computation of the froude number.
GeomPreprocessor (internal boundary curves):
Bridges (or culverts) that have multiple blocked ineffective flow areas could cause problems with the internal boundary curves.
Unsteady (I.B. stage/flow):
The internal boundary (force a known stage and/or flow at an interior cross section) had a bug that could cause the known stage/flow to be applied further downstream than the user specified.
Steady (multiple critical depth):
When the program computed multiple critical depths, the critical depth that gets selected has been modified. Where it used to select the lowest valid water surface, it will disregard the lowest water surface if it has an unreasonably high energy.
Steady (weir flow):
Prior to version 4.1.0, weir flow for bridges was based on computing weir flow over the upstream road section. The program is now checking to see if the downstream road section is more constricted. Whichever section will constrict the flow the most is then used as the controlling section.
Unsteady (critical flow):
The option to reduce the time step based on changes in the flow hydrograph ("critical" boundary condition) was not working for a lateral inflow hydrograph.
Unsteady (Dam and Levee Breach):
The breach was not growing during the very first time step after the breach should have started. This "missed" growth was then being added to the very last breach time step growth (so it would essentially have a double growth on the last time step).
Steady (lateral structure/flow optimization):
If a lateral structure that was being flow optimized also had multiple cross sections on the tailwater side, flow was not being transferred to the tailwater side (the flow was going out of the system).
Import Station Elevation Data:
Version 4.0.0 attempted to filter colinear points and introduced a bug that sometimes did not import the last point.
The menu item on the Geometric schematic editor:
"GIS Tools/GIS Cut Lines/Adjust Cut Line Lengths to Match XS Lengths" loads an editor that allows users to automatically adjust the lengths of cross sections to match cut line lengths or cut line lengths to match the cross section length. This dialog did not have a mode to leave user specified cross sections alone, if the option was selected, then all cross sections in the selected reach were adjusted. A "none" option has been added so that users can leave some cross sections without adjustment.
The unsteady flow editor in version 4.0.0 has a new button that plots all the inflow boundary conditions on one plot"
The axis for this plot was off by a factor of 24 (hours were plotted as days). This problem has been fixed.
The DSS file viewer: would crash when reading a DSS file that had no
data. Fixed in 4.1.0
Exporting GIS data with no output profiles selected caused the program to crash.
Exporting GIS data could cause the program to crash if there were different number of profiles selected for export previously than now currently exist.
The culvert editor for Box culverts Chart #9 had only one scale (#2), but was actually using scale #1. This has been fixed and both scale #1 and scale #2 are now available.
Background Image Files in Geometry Editor:
There was a problem storing references to background image files if they were not stored on the same drive.
The summary of errors warning and notes would produce an inaccurate list of errors for multiple openings with culverts in them.
Node Specific Output Table:
In the node specific output table with the table in the inline weir mode, the program would display an error message if you picked a reach without an inline weir.
Vertical Variation of Manning’s n:
There was a problem with allocating enough space in the computation engine when the XS above an inline weir used the vertical variation in Manning's n.
Pump stations can now copy data from one station to another.
Profile Plot with Lateral Culvert Structures:
Plotting filled in culverts on lateral structures did not position the bl ocked graphic on the profile plot correctly.
Exporting GIS bounding polygon was incorrect when some of the XS's were not found in the output file. A message has been added warning users when specific XS's were not found in the output when generating the GIS export file.