Civil 3d Grading Pad and Swale

[tehparadox86]

Any suggestions on how to get this done. FFE for garage is 665.50 to make the be slightly above the existing parking lot of around 694.38. I need to cut down on the west side and drain to the existing inlet on the northwest corner of the garage at 693. I just need to keep the existing sidewalk intact while grading down from around elevation 700 to create a swale towards the flowline (circled in blue)? How would I do that in Civil 3d? I'm struggling with feature lines to get the contours to look correct in the Existing ground surface.

 

[cmoreride]

Create 3d polys to use as feature lines at known X,Y,Z's to constrain and modify a surface.