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I am using ArcGIS Pro.

I have two land maps which are each polygon feature classes composed of multiple polygons. I want to erase overlapping features by using the erase tool.

To ensure the erase has performed correctly, I perform a intersect between the newly erased layer and the feature class used for the original erase. There should be no intersections.

Unfortunately, intersections do occur as one or two tiny polygons are not erased fully.

I've tried the following tools to no avail: repair the geometry, turning multipart into single part and setting the extents to "union of inputs" under environments on the erase tool.

I've tried running erase in a new ArcGIS project but the same issue occurs which leads me to believe the erase tool is struggling to handle the featureclass datasets.

Images of workflow:

I am erasing the blue layer by the overlapping yellow layer.

enter image description here

The pink layer is the output of erase. The erase has not erased the intersection correctly. I have circled the error.

enter image description here

I run intersection between the erase tools output (pink layer) and the original layer which was used to erase (yellow layer). There should not be any intersections between the two. Unfortunately there is (orange polygon).

I've uploaded a clipped that includes the two layers used in the erase function (yellow and blue) and the intersecting polygon that does not get erased (orange).

enter image description here

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    Please Edit the Question to specify the exact release of Pro in use.
    – Vince
    Commented Jul 11, 2020 at 12:24
  • Do the two layers share a common CRS? Also, note that the spatial selection option intersect will identify contiguous features that merely share a vertex. You may want to just run a spatial selection on crosses or overlaps instead.
    – jcarlson
    Commented Jul 11, 2020 at 13:51
  • @JoshC it seems the problem layer does have a slightly different CRS. I believe this may be the problem. However, I'm struggling to correct this issue. For example, I've just tried changing the CRS via 2 ways. 1) project tool: the tool runs successfully, however the problem still persists. 2) Define projection tool: the layer becomes distorted, on a different area of the map and fails to erase anything with the Erase Tool because it no longer intersects any other layer. Any idea how to solve this?
    – EdyK
    Commented Jul 11, 2020 at 15:06
  • @JoshC Update. I just made all layers share the same CRS by importing them into a file geodatabase feature dataset. However, the error still persists where erase will not perfectly erase the intersects leaving small intersecting areas un-erased.
    – EdyK
    Commented Jul 11, 2020 at 16:03
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    @EdyK Well, I've got the least helpful kind of comment, which is that performing the erase on my machine doesn't result in the same problem you're experiencing. Try this: run a Union on the layers, then select features by erase_layer_attribute IS NOT NULL and delete them. This should leave non-intersected features from the input layer, and you can remove the joined fields. If that works, I can post it as an answer here.
    – jcarlson
    Commented Jul 11, 2020 at 18:44

1 Answer 1

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The problem arose due to a difference in CRS between base shapefiles. I reprocessed the shapefiles ensuring a shared CRS between shapefiles.

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  • Please edit your answer to give some steps you used to ensure a shared CRS
    – Midavalo ♦
    Commented Jul 13, 2020 at 14:36

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