Modifying DEM with new elevation data measured at specific points

[AleksadarSlavnic]

Hi 😀,

How to modify existing DEM file with new (more accurate) elevation data that was measured at several different points by the geodetic service in the field.
The problem is that the elevation at specific points measured by the surveyor do not match elevation in DEM file.
It is necessary that the points where the elevations are measured when they are applied to the DEM have the same elevation value as the corresponding elevation on the DEM.

Is there some specific tool that I can use or workflow for correlating existing DEM with new elevation data_

Using ArcMap 10.8

[jcarlson]

I think you'd need access to the dataset used to create the original DEM, as well as the process used. Do you have good metadata on the DEM? Suppose, for example, that the DEM was generated using inverse distance weighting. The distance between input points changes the output interpolation, so if your new, more accurate points fall closer or further to those original elevation points, the manner in which the DEM is adjusted will vary.

If, however, you've got elevation points that simply differ from the original input, then you've got to come up with some way of either weighting the new points more than the old, or else removing older points, but these will require some kind of judgement calls prior to running any GP tools.

[AleksadarSlavnic · Accepted solution]

Thank you very much Josh Carlson,
I am new to ArcMap so everything is a bit complicated for me.

I'm working on a project where I need to represent elevation observation points on the isohypse map. The coordinates of these points along with the associated altitudes were measured by the geodetic service, which means that they are 100% accurate. When I insert these observation points on the isohypse map I see that my DEM is not accurate enough because the isolines I created based on it do not match the elevations in specific points that I know are representative.

I thought there is a tool in ArcMap that will do additional interpolation in DEM by taking new points into account that I know are accurately measured.

Once again, thank you for trying to help.