[cameron]

For multiple openings, you specify starting and ending values for each opening. If two openings overlap, you the program tries to determine where the stagnation point is located. You need to adjust starting and ending points to fix the issue.

[cameron]

Just changing the output interval in HMS from 1 min to 1 hour will have a huge impact on results in HMS (before input into HEC-RAS). Generally in HMS, the lower the output interval the higher the peak discharge you get in HMS.

As for the tolerance values, they do make a difference for rainfall values as they are generally really small.

[cameron]

do all of the station values along the XS increase?

[cameron]

there are two types of flow files: Steady (f01) and Unsteady (u01). They can’t be mixed. DSS files from HMS are for unsteady models and volume is important. You can also just enter data for Unsteady models without DSS.

If you want to use sort of create a Steady model in Unsteady, you would use a constant inflow for a very long period of time.

[cameron]

HEC is doing a training on HEC-RAS 5.1 at the SEDHYD conference in about a month. They will be discussing infiltration among other things. The link below is to the workshop for the conference.

I have heard multiple things for estimates of when it will be released and it is always changing, but probably within a year from now is a safe guess. Hopefully at the workshop, they can provide a more solid answer.

https://www.sedhyd.org/2019/openconf/modules/request.php?module=oc_program&action=page.php&id=112

[cameron]

There is not a newer version of cHECK-RAS

You don’t need any special tool to create a floodplain. All you need is ArcMap or QGIS and set up the attributes following the technical guidance for the SFHA layer (see link below).

https://www.fema.gov/media-library-data/1556723016910-db56f22acada9046862b968b44e86b8f/FIRM_Database_Guidance_Feb_2019.pdf

If you do want the FMD tool from Atkins go to the link below where you can enter in some info to get an email with the download. This tool can help with the creation of FEMA data, but not required.

http://floodmapdesktop.com/products/

[cameron]

The program looks for whatever files are listed in the *.prj file. If you hit save after you see that message, they will be removed from the *.prj file. The other option is to delete them from the *.prj file, which is what I normally do.

You also have to make sure that whatever is listed in each plan file (*p01) still exists (*.g01, *.f01, or *.u01).

[cameron]

If you set the Sta W.S. Lft and Sta W.S. Rgt in the output table, it will give you the left and right stations the water intersects the ground. You can then just subtract the 2 to get a width.

[cameron]

In the connection editor there is a button that says clip weir to 2D cells. That will fix it.

[cameron]

You need to use a 2D connection which can connect multiple 2D areas together.

[cameron]

I probably wouldn’t worry about them if they are that small as the error from the uncertainty in breach parameters and breach hydrograph is probably a lot higher.

[cameron]

Your weir elevation cannot be lower than the cell elevation. Your weir elevation is about 3 times smaller than the cell elevation. Probably metric to English units conversion error.

[cameron]

I have never been able to do it. It does not represent reality as they are tweaking things to just make it look nicer.

The only issue with render mode and exporting out rasters was part of the 5.0.5 fix. The link below shows all of the fixes since 5.0.0

https://www.hec.usace.army.mil/software/hec-ras/documentation/HEC-RAS_5.0.7_Release_Notes.pdf

[cameron]

What I would do then is create a wse raster of the 100yr floodplain and subtract it from the the breach wse raster. The zero contour would be the edge of where they meet.

[cameron]

The 100yr floodplain should be available in GIS format as part of the NFHL database. All you should need to do is clip your breach inundation map to the 100yr floodplain.

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