Is there a way to import a .tin file from Carlson Survey into Inroads? I have the 3d triangles with elevations as a backup.
I believe Carlson has a tool that you can create a LandXML file from surface, then you can use the Inroads tool to convert the LandXML back to surface(DTM) into InRoads format.
In addition to using the InRoads LandXML Translator to import the data, you can also import raw data from Carlson.