The Cross Section method

More accurate than a single profile along the centerline
Done by measuring cross sections (profiles) at a right angles to the centerline, usually at intervals of 50, or 100 ft
Reading at each cross section is taken at the centerline and at critical points.
Cross sections are drawn and design templates are superimposed, the difference in area is the are of cut or fill at that section (end area)
End areas could be cut, fill, or transition (both).
use the areas to compute volumes, knowing the distance between the sections.
The whole work could be done with photogrammetry and computer software.