Feature line-to 3d polyline-to 2d polyline

I hope someone can help me with this.

(In CIVIL 3D)

I work at a structural engineering company that just started a Land Survey department about a year ago. After we have create a surface in Civil 3d, the Engineering department wants us to send them a file where the feature lines used for our breaklines have been converted into 2d polylines so they are easier to work with. The only way I know how to do this is to explode the feature lines, then select the 3d polylines, and convert the 3d to 2d polylines under the "Modify" tab. However this creates many small line segments along curves instead of one smooth arc. Does anyone know how to convert feature lines to 2d polylines without exploding and creating these small line segments?

Sorry, there are not many (any?) active members here anymore.
Things change, people move.

I suggest that you ask over at CadTutor forum, most of the previous regular users from here are now found on there and there are some good Civil 3D users who should be able to help you:

https://www.cadtutor.net/forum/