Corridor Properties > Surfaces tab. Click the "Create new surface" button. Give it a style, specify the code you want your surface to represent (probably Top), click the "+" button to add that code to your surface, click OK, and you're done. If you need a boundary, there is a Boundary tab, too.
Which data types do you generally add? I have a pretty generic situation: 13' lanes, curb & gutter, daylight to existing topo. Add as breakline for each?
Typically you would use links as surface breaklines. Generally none of the longitudinal features are necessary.
Steve
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