Yes, you can generate river cross sections and input for HEC-RAS / HEC-2 using AutoCad 2002 and Land Desktop 3.
A) Define your cross sections in Land Development with lines or polylines (1 or 2 line segments allowed per cross section)
B) Use Land Desktop 3 command "Hydrology - HEC2 Output" to create a text output file (ASCII format).
The text output file will have river cross section data. The file will also have the minimum data necessary to run HEC-2.
C) Use the text output file with HEC-2 or with HEC-RAS. For HEC-RAS, use command "File - Import HEC-2 data file" to use the text file you created.
-Sarah
scraig@co.santa-barbara.ca.us