If you go visit the Subscription Center, you’ll find that there are new extensions for C3D. The two import formats are fairly obscure (but French and MX users will be happy) but the HEC-RAS, Stage-Storage and new Subassemblies are pretty cool. I had problems getting the RAS installer to recognize my build, so I went around it and installed manually. Read how after the jump.

The extension is nothing but a DVB file, and the installer does little more than place a Toolbox XML file in the right place, so you just have to do these things manually. These instructions are for XP. I’ll see if I can track these items down in Vista later (Jason, Eric?)

1. Extract the installer someplace like C:\AdeskRAS
2. Navigate to C:\AdeskRAS\Content\cp_C3D_CONTENT_EXT_HECRAS\DataDir.cab
3. Pull the XML and DVB file out to your desktop for temporary storage.
4. Select the XML file and right-click to copy it.
5. Navigate to C:\Documents and Settings\All Users\Application Data\Autodesk\C3D 2009\enu\Data\ToolBox  and paste the file.
6. Select the DVB file on your desktop, right-click and select Copy.
7. Navigate to C:\Documents and Settings\All Users\Application Data\Autodesk\C3D 2009\enu\Data\Reports\vba and paste the dvb file in.
8. Launch C3D.
9. Open the Toolbox and enjoy your HEC-RAS happiness.

And remember, if you have a problem, contact Autodesk. If you love the application, let us know, it used to be my baby. Oh, and it appears your RAS sections have to be in a sample line group. That’s one of their “improvements,” not ours.

Basic channel geometry is just part of the equation, be sure to watch here for the next generation of this tool, including automatic floodplain generation and water volume generation.