% Overlap between two polygons

Question

Hello,

I am trying to work out the % overlap between two polygon layers. To do this I:

* Imported my point locations and created buffers around these
* Ran an intersect (input features = buffer layers created)
* Calculated the area of the intersect using the calculate geometry option
* Calculated the % overlap((Overlap area / original area) *100)

However, I have ran into some issues where there are multiple polygons in the one area. For example, I am looking at the % overlap between the buffer around the red point (circled) and the buffer around the green point. However, the intersect created suggests this area is only small (see selected area highlighted in blue) and therefor does not provide an accurate % overlap (only 1% when it should be a lot higher).

Any suggestion on how to avoid this error, or will I need to run the intersect tool for each location individually?

Thanks in advance!

MervynLotter · Answer

If you have an Advanced license, then do consider trying the Tabulate Intersection tool for quickly finding the % overlap between two features classes. Do see Tabulate Intersection (Analysis)—ArcGIS Pro | Documentation The output percentage field may be over 100% if there are overlapping features so it will be important to first follow David's suggestion to assess the extent of overlapping polygons.

RachelKnell · Answer

perfect, thank you!

LTS_DSolari · Answer

Count Overlapping Features can also generate a table linking every input buffer to the final overlaps. You can use that table to find which overlaps relate to which buffers and ensure you're only summing up the appropriate polygons.