In order to run a hydrologigal analysis I'd like to to merge two raster datasets (DEM and buildings) to get as result one raster with only the highest values (elevations) of both. In other words: To overlay the DEM with the buildings and to use the buildings-values whenever possible.

I'm working with ArcGIS 10.4 (ArcMap/ArcScene) for this.

I've got the following input data:

  • DEM as raster
  • builidungs as raster (with Null-values outside the buildings)

I was wondering if its possible to use an IF-statement in the Map Algebra Tool, but didn't get the right syntax or maybe there is a better way to do it. The If-statement could be similar to this: If ("buildings1" IS Null, "DEM1")

enter image description here


You can do this just by using the Mosaic to New Raster geoprocessing tool. Just choose maximum for your Mosaic Operator and the new raster will use the high value anywhere that they overlap.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.