Dear Bruce Randell :
In RiverCAD 2000, from the HEC-RAS Module, select Input | Levees. The Levees dialog box will display and you can then defined where the levees are. I assume that it is similar for RiverCAD 3.5.
Note that levees are defined differently for HEC-2. This is done in the Cross-Section Description dialog box. Select Input | Cross-Section Description. From the displayed Cross-Section Description dialog box, define the left and right bank elevations. It is assumed, in HEC-2, that the levee stationing correspond to the bank stations.
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