I'm using the Eliminate Polygon Part tool in ArcGIS to remove dry land surrounded by water (aka islands).

Tool Inputs:
Condition: AREA
Area: 50,000 Square Feet
Percentage: 0
Eliminate contained parts only: CONTAINED_ONLY
(There were no errors, the tool completed successfully)

It is my understanding, according to the Help, that by using this tool that any island 50,000 square feet or less will be absorbed by the polygon that is surrounding it (and therefore it will be "eliminated"). But, while that is happening, it seems something else is going on as well.

Actual polygons are being seemingly "removed" in the final output (which is weird in and of itself, because I didn't think this tool was supposed to remove actual polygons), but also, the output makes it appear that those polygons have been eliminated, when in fact, upon closer inspection, they are still there, "underneath" the larger polygons.

I'm confused. Is this supposed to be happening, am I misreading how to use this tool, or is this a bug? I could only really find two questions pertaining to this problem here and here, but no answer.

Image Descriptions:
The image on the left is the original feature class. The image on the left is after I run the tool. Upon investigation I found that areas that seem to have disappeared in the feature class on the right are actually there (e.g. area selected in blue). You can see the selected feature in the right-hand image in the image on the left, but you can only see it in the image on the right after I've selected it and it becomes highlighted. (I found these areas when multiple features were unexpectedly selected while using the Identify tool).

enter image description here

  • Please edit the question to contain the exact inputs you have provided to the tool (as submitted to geoprocesing), and any output it generated. – Vince Oct 29 '15 at 19:58
  • @Vince Not sure what's missing. I wrote that I chose "Area" as the "Condition" option with 50,000 square feet as the area size. I also included two images, one of the input and one of the output. Can you please clarify what you'd like to see in addition to that? – Kristen G. Oct 29 '15 at 20:34
  • The exact text of the command submitted to geoprocesing and the exact output from the GP results window – Vince Oct 29 '15 at 21:09
  • Question has been updated with exact GP inputs/outputs – Kristen G. Oct 30 '15 at 13:21

If your goal is to have the selected features be eliminated into the surrounding features, then seems like Eliminate is the tool you're looking for.

  • But I wasn't actually looking to remove features (which is why i thought it was odd they were being removed at all). I just wanted to fill in empty non-feature areas to generalize things a bit. In a previous step in my process I actually used Eliminate to do just what you're suggesting here. – Kristen G. Oct 29 '15 at 22:58
  • Ah ok. Eliminate Polygon Part will fill in the interior ring of a feature (the hole in the donut), but if there is a second feature that fills that hole, it will still continue to exist. Whether it is 'visible' will depend on the order of the features, so it may end up hiding behind the other feature. – DWynne Oct 30 '15 at 22:54
  • I think that is exactly what happened. What I ended up doing was writing a Python script that actually runs the Eliminate tool, like you suggested, to generalize the whole feature class. I used Python because it has to run the tool until the number of areas under 10,000 (per my Question above) reaches 0. I think that tool runs into the same problem. If there are islands within islands, it'll only eliminate the first island. You have to run the tool to get the next island, and so on and so on, if that makes sense. – Kristen G. Nov 2 '15 at 15:48

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