Doing a floodway analysis with RiverCAD - Free Online Discussion Forum For Hydrology and Hydraulics Software

#1 (**permalink**) 08-20-2002, 02:55 PM

Chris,

I followed the directions given in the engineering forum exchange, but when I tried to run RiverCad with Method 1 encroachments I received only the message that "The first tagged profile contains encroachment data" and "An HEC-RAS data file cannot be generated". Where am I going wrong?

Dan Hoggan

#2 (**permalink**) 08-20-2002, 02:56 PM

Dear Dan:

Note that when you do a floodplain encroachment model using HEC-RAS (and RiverCAD) Encroachment Method 1, you need to have 2 discharge profiles defined. The first profile is considered the natural (unencroached) profile. The second profile is the one that the floodplain encroachments are applied to. This water surface elevations from the second (encroached) profile is then compared to natural (unencroached) profile.

Perhaps you only have 1 profile defined, or have only 1 profile tagged? This should explain the problem you are running into.

If you have any additional questions or need any further information, please contact me again.

Sincerely,

Chris E. Maeder, M.S.
Senior Technical Engineer
chris.maeder@bossintl.com

#3 (**permalink**) 08-20-2002, 02:57 PM

Chris,

Thank you! Your tip was just what I needed. I am able to do the floodway now.

I have another question. When I do the water edge boundary for the 100- yr flood using the floodplain mapping results under the output option, I get a lot of little islands produced as well as the boundary around larger floodplain. When I try to delete these, I get the message that, "The entities you selected cannot be deleted". Is there anyway I can turn off a lock so that I can delete these islands that I don't want on my drawing?

Dan H.

#4 (**permalink**) 08-20-2002, 02:58 PM

Dear Dan :

Anything that happens to be drawn on a "BOSS" layer will not be allowed to be deleted by the end user. This is because we have attached extended entity data (i.e., database entities) with the drawing entities (i.e., lines, points, etc.). However, you can get around this by saving the RiverCAD drawing file out to an AutoCAD DWG or DXF file (using the File | Save As command) and then opening the drawing file in AutoCAD or MicroStation. From the other CAD program, you can delete anything you want.

If you have any additional questions or need any further information, please contact me again.

Sincerely,

Chris E. Maeder, M.S.
Senior Technical Engineer
chris.maeder@bossintl.com