Looking at the image below, at first, it may appear that you need multiple surfaces; one for each area (pond). But in Civil 3D a single surface can represent multiple spot areas by using the OUTER and SHOW boundaries.
Two practical everyday uses:
Spot Grading along a Corridor Model (endwalls, ponds, custom daylighting, etc…)
To make this work it is as simple as placing an OUTER boundary around Pond 1 and a SHOW boundary around Pond 2.
In the example below we first use Featureline tools to grade in the two pond bottoms.
Next, we make an E&S surface – in this example called "ESC" – and add the breaklines (see the image for notes).
Finally, create two boundaries for the grading areas – in this case pond 1 & 2 – and add one as an OUTER boundary and the other as a SHOW boundary.
After the boundaries are added the surface should clean-up the spanning contours and you should be set to go.
IMPORTANT NOTE: from this point you can add as many pocket areas as you would like. Just grade in the area and add another SHOW boundary around your grading.