Cut & Fill Tool

The Cut & Fill tool gives the earthwork of an area: how much soil to dig out (cut) and how much to bring in (fill) to bring the existing ground to a design surface. Use it for a bed, a mound, a pad, a driveway, or any area.

1. Click Tools in the bar at the top of the map, open Septic design, and click Cut & fill in the Site group. A panel opens at the bottom of the map.

2. Set the area:

   • Draw an area: click on the map to add the corners. Double-click or press Enter to finish, and Esc to cancel. You can drag the corners afterwards; the volumes update.
   • Pick a polygon: click a polygon already on the map (a bed, a building, a hardscape, the parcel...). The smallest polygon under the click is used.
   • Use a bed: choose one of the beds drawn on the map.

3. Set the design surface:

   • Flat: level at one elevation.
   • Sloped plane: an elevation at the center of the area, a slope in percent and the direction it falls toward.
   • From the design: for a bed, its design elevations (bottom, at grade, top of pipe, or its first trench's bottom). The bottom is chosen first: it is what the excavation is graded to.

   Balance cut and fill moves the surface up or down until the cut equals the fill. Average ground sets it to the average ground elevation of the area.

The panel shows the cut, the fill and the net volume in cubic yards and cubic feet (and cubic meters in a metric project), the area, the cut and fill areas, the average and deepest cut and fill. The map shows the cells of the area: orange where the ground is cut, blue where it is filled, darker where it is deeper, and grey where no ground elevation was found.

How the volumes are computed

The ground elevation is read on a square grid inside the area, from the processed elevation tiles of the site when there are some, else USGS 3DEP and the other elevation services (see the elevation process). The grid is as fine as possible within 2,000 elevations (1 m at the finest); you can choose its size in Grid. Each cell, or the part of it inside the area at its edge, counts its area times the depth between the ground and the design surface.

Cells without a ground elevation are listed and left out of the volumes; they are never counted as 0. Read the elevations again with the refresh button, for example once the site's elevation tiles are processed.

Download the grid (csv) saves every cell: where it is, its area, the ground and design elevations and its depth.

On the cross-section sheet

For a bed, Save on the bed keeps its cut and fill. The bed's cross-section sheet in the report then prints it as an earthwork note in its general notes: Earthwork from the ground elevation model, with the cut, the fill and the net. A cross section you download from the cross-section view also lists it under the material quantities. Run the tool again and save to update it.

See the report sheets for the cross-section sheet.

WARNING

The volumes come from elevation models and are estimates before compaction. Verify the grades on site.