Grading in an irregular terrain

[Anonymous]

Hello,

I have a terrain that needs to be leveled and the proper cut & fill added to it which is easy to do using feature lines and the grading creation tool with criteria. However, my employer wants me to have the whole terrain starting at elevation 18.375 (south) and going to 15.875 (north), which is close to a -2% grade. I also need to have a "line" dividing in the middle so it falls -0.5% in each direction (East and West). When I try to alter the elevations by points, the whole drawing has different elevations and gradings, it's not something linear. How do I achieve that south to north grade and the "middle" to both directions -0.5% grades in a linear way that applies to the whole model? 

As you can see I already added the cut & fill, just having problems with the elevations...

[MMcCall402]

My first thought is to have a  feature line running South to North at the approx. -2% slope with grading to the East and West from that feature line at -0.5%, however that may or may not intersect the original surface at the desired limits.  Is there some additional info in the desired result around the graded area's perimeter?

If there is a desired perimeter you could make a feature line at that location ad grade inward toward a surface created by the above feature line/grading.

Or, the top feature line/grading surface could serve as a source of elevations for a feature line near the perimeter and then graded outward to the original surface.