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I need to calculate removed material volume on arcmap 10.2. I have a present-day dem and a very large and irregular polygonal shapefile that is the area in which I have to calculate volume. How can I reconstruct the putative earlier topography and make the difference between the two in order to estimate the volume of the removed material?

  • You need before and after Dems. One of them is missing. What these polygons represent? Future flats, ponds? What are the rules, e.g. slopes? – FelixIP Oct 5 '16 at 18:38
  • I don't have two dems. I have only the present-day topography. There are no previous data. I want to count on an inclinate plane (my shapefile that is not inclined now) that intersects the topography and estimate the volume. between the dem and this plane. – ilaria Oct 5 '16 at 19:29
  • Such thing as 3D polygon does not exist unless it is triangle. You might try to convert your polygon to line, interpolate it using 3D toolbox and create TIN from line using polygon as soft clip. This will give you future DEM. Depending on polygon shape results can be disappointing – FelixIP Oct 5 '16 at 21:34
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You could clip your DEM using the polygon and the Extract by Mask. Then use the surface volume tool to calculate the volume. Keep in mind that the polygon and the DEM will need to share a common coordinate system before clipping.

  • but...is the polygon on a planar plane, isn't it? I shouldn't be in order to be accurate – ilaria Oct 6 '16 at 10:35
  • Oh, right. The excavation is a sloping plane? Do you know the new elevations along the edge of the slope in at least 3 places, or do you know how deep the excavation was at a few places along the polygon? If so, use those elevation values to either construct a Polygon Z (desktop.arcgis.com/en/arcmap/latest/extensions/3d-analyst/…) and then (or just use those elevation points to) construct a TIN that represents the newly excavated topography. Convert the TIN to a raster. Use the CON tool to make a raster that represents the new surface. Then Cut and Fill. – GBG Oct 6 '16 at 15:43

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