Accounting for differing grades around retaining walls

I think there may be a slight misunderstanding about phases.

Looking through your project, I actually think the phase structure is good. I wouldn't split the Grass Areas, Paved Areas or Sidewalks into separate phases. If you did, the Grass Area calculation would become the ground surface for the next phase, meaning the Paved Areas and Sidewalks would calculate against the finished grass rather than the original ground.

The main improvements are around how the elevation elements are being used.

You don't need the four "exclusion" outlines in the Grass Areas. 

   

Instead, let the Grass Area Feature Surface extend underneath the other elements and use the element order to control what is shown. Elements lower in the list override those above them.

Turn on Snap to Boundary, redraw the outer Grass Area boundary by snapping to the existing points, then remove the exclusion outlines. After recalculating, enable Element Colours in the Display menu and you will see the Paved Areas, Sidewalks and Basin correctly displayed on top of the grass.

   

You will also notice the Building Pad is currently hidden by the Sidewalks. Move the Building Pad lower in the element list so it overrides the sidewalks and calculates correctly.

   

The only area I would change is the retaining walls (as Leah said in the previous response). These would be better represented using breaklines within a Feature Surface rather than a Path, as this gives better control over the level changes.

Overall, the project structure is good. I'd focus on element ordering, overlapping Feature Surfaces and using breaklines where needed rather than changing the phases.

We also have sections on Construction phases  and Calculation Order in the user manual that explains this workflow.

<p><br></p>