Issues combining surfaces

[crewsmolly45]

Hello, I am super new to Civ3D. I am having issues with the way autocad combines two surfaces. I have tried slicing instead of using paste surface, but it seems you cannot slice a surface with a surface?

If I select the two surfaces and view them in object viewer, I can see exactly where I need it to "trim" the surface. If it would let me ID an point of intersection of the two surfaces, I could just build a new one myself, but it will not. Using paste surface (I have tried reversing the order of selection as well) does not give me the surface I am looking for. I need it to combine where they both intersect and trim the rest. 

Any advice on how to get this to work? I attached the DWG and a word file with pic for reference

[ChrisRS · Accepted solution]

I am answering from my phone without access to Civil 3D.

The "zero" contour from a Volume surface method works well, but MINIMUMDISTANCEBETWEENSURFACES is quicker.
Follow the prompts on the command line and chose yes to creating polyline.

Let's say you want to paste Surface2 into Surface1.

I would create a working surface called Trimmed. Paste Surface2 into Trimmed. Use the MINIMUMDISTANVENETWEENDURFACES, choosing Surface1 and Surface2 and creating polylines. Add a outer boundary to Trimmed using the resulting polylines.

Ceate an additional surface called Combined.

Paste Surface1 into Combined, then then paste Trimmed into Combined.