Thanks for that insight Matt. My user has imported the GIS data but the Reach Invert Lines option is greyed out.
Sorry but neither of us have experience with HEC RAS.
Infrastructure Suite/C3D 2013, LDT 2004, Power Civil v8i SS1
WIN 7 64 PRO
HP Pavillion h8xt, i7 2600, 12 GB
RADEON 6450, 1 GB
You have to use the Geometric Data --> GIS Tools --> Reach Invert Lines Table command directly after importing GIS information, otherwise, HEC-RAS won't let you modify it.