Dear Community, I am trying to use the Multiple Ring Buffer tool to create a set of non-overlapping buffers (e.g., 100 m, 200 m, 300 m, 400 m) around 50 polygons, which are different sites. I am running into a few challenges: * The non-overlapping option of the dissolve parameters creates multipart buffers, whereas I need them to be singleparts (i.e., each buffer around each site should be a separate polygon). Trying the multipart to singlepart tool does not work because some of these buffers overlap, as some sites are somewhat close to one another. * Whereas the overlapping option of the dissolve parameter returns the attributes of the original polygons (around which buffers are formed), the non-overlapping option does not return the attributes of the original polygon. To sum up, I am trying to generate a series of non-overlapping buffers (rings) around multiple sites. Then, I need to know which buffer is associated with each site, so I would ideally have an attribute in the buffer shapefile that corresponds to the site id. I would be grateful for any suggestions on how to achieve this!

how I understand it is that the the Geodesic buffer in NAD1983 Geographic is not a regular annulus or circle. The circle or annulus will be like a squash ball squished against the poles. This greater area of the buffer above the buffer origin point (for Northern Hemisphere) then forces the Centroid up to account for the changed centre-of-mass. This will increase non linearly as you increase the buffer distance. I'd use a big (1000km) geodesic buffer and then visualise it in the same geographic projection. I think when you see that it would make sense what's occurring. For the UTMZ13 coordinate system I may be wrong in this one as this topic is admittedly very confusing - but it seems to me that it's showing the distance distortion away from the central meridian of the transverse mercator projection (105 West?). I would then say your buffer point is West of -105 degrees, and if you recreated the example with a point East of -105 degrees you would see the centroid shift in the opposite direction.

Well, I repeated the experiment and here's what I got: I ran it twice: once on a point in NAD 1983 (GCS, WKID: 4269), and once on NAD 1983 UTM Zone 13N (PCS, WKID: 26913) Steps: * Set map to the spatial reference * Create point feature class in matching spatial reference * Create point feature * Calculate its XY in the same spatial reference * Use multiple ring buffer tool on point, once using planar and once using geodesic * Calculate the centroid of each buffer * Compare buffer centroids to point. Here's what I found: * NAD 1983 (Geographic)* Calculating the centroid for the geodesic and planar buffers yielded the exact same results. * That said, they were not the original point * * NAD 1983 UTM Zone 13N (Projected)* The centroids of the planar buffers matched the original point exactly.* Well, except for it rounded the X. * The centroids of the geodesic buffers varied from each other and from the original point.* Interestingly enough, they spread out on the X axis this time *

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Creating multiple non-overlapping buffers

GeoQuest4567

Dear Community,

I am trying to use the Multiple Ring Buffer tool to create a set of non-overlapping buffers (e.g., 100 m, 200 m, 300 m, 400 m) around 50 polygons, which are different sites. I am running into a few challenges:

The non-overlapping option of the dissolve parameters creates multipart buffers, whereas I need them to be singleparts (i.e., each buffer around each site should be a separate polygon). Trying the multipart to singlepart tool does not work because some of these buffers overlap, as some sites are somewhat close to one another.
Whereas the overlapping option of the dissolve parameter returns the attributes of the original polygons (around which buffers are formed), the non-overlapping option does not return the attributes of the original polygon.

To sum up, I am trying to generate a series of non-overlapping buffers (rings) around multiple sites. Then, I need to know which buffer is associated with each site, so I would ideally have an attribute in the buffer shapefile that corresponds to the site id.

I would be grateful for any suggestions on how to achieve this!

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BobBooth1

Might try using the multi-ring buffer tool in a ModelBuilder model with an Iterator.

https://pro.arcgis.com/en/pro-app/latest/help/analysis/geoprocessing/modelbuilder/iterators-for-looping.htm

Use Inline Variable Substitution so each of the output feature classes (one for each of the sets of buffers) has a unique name.

https://pro.arcgis.com/en/pro-app/latest/help/analysis/geoprocessing/modelbuilder/inline-variable-substitution.htm

Append the feature classes together.

https://pro.arcgis.com/en/pro-app/latest/tool-reference/data-management/append.htm

Ed_

For this part "Then, I need to know which buffer is associated with each site" maybe try: the buffer, since it's a circle, its centroid should be pretty close to the site centroid. So, with those centroids you can do a nearest spatial join to get the site id to know which buffer goes with which site. I am sure there might be a better straight froward way to do this.

For the sites that are completely within its buffer with no other site overlapping that buffer, you may try a completely within spatial join

DavidPike

I think you have a simple option of a spatial join to the original points with 'Have their Center in'. the Centroid of any buffer ring will have a centroid coincident with the site.

AlfredBaldenweck

Multiring buffer should include data with the original feature. Unfortunately, as you have found out, that doesn't work if the Donut option is chosen. Here's a relevant Idea: Analysis Tools: Multiple Ring Buffer: Don't dissol... - Esri Community

To Ed's point, it turns out the centroids of each buffer are different, which is super frustrating.

So, here's a toolbox with two tools to fix that.

They turn the disc output of multiring into donuts without sacrificing the attributes.


Before	After

One tool (Punch out buffers) works after you've made the buffers, while Clean Donuts buffers the input feature and gets the nice donut result all in one go.

I've only lightly tested these, so your mileage may vary, but it's worked for me so far.

I'll be sharing this toolbox to that Idea as well.

CleanMultiRingBuffersPYT_20250421.zip

DavidPike

I don't understand how or why the Centroids would be different for a donut annulus, even for multipart polygons.

AlfredBaldenweck

I don't know why either, but here's the proof:

When I was figuring out the code, my initial thought was to go by centroid.

Note that the buffers and the original point are in this coordinate system.

Original point at the bottom, with the other three buffer centroids above.

You also get different stuff if you check arcpy geometry.

So, anyway. They do not have the same centers, which means that if you try to match centroids, you won't get any results.

My solution was to check the ORIG_FID field and work with that. You can check my code to see how I did it.

Full disclosure, I have a hard time with coordinate systems and stuff, so that may be another wrinkle to this, but I tried to keep everything consistent while testing this.

AlfredBaldenweck

Also, to be fair. That initial test I just showed was buffered geodesic. Buffering planar (again, keeping spatial references consistent) gives a much tighter spread, but a spread regardless.

BobBooth1

You could set up a model to use the ordinary buffer tool. Buffer the input polygons once. Then buffer the resulting features, and then buffer the next set of resulting features. Then, append two of the result feature classes into the other one.

Seems like it works.

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