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Using ArcGIS Pro version 2.7* updated from 2.6.0 (which did not solve this issue)

I built my own network based on street center-lines data. I'm not concerned with looking at vehicular speeds or direction along the network at this point so I'm using length as my 'cost'.

I input the facilities and set the distance to feet, established the breaks at 150, 300, 450, and 600 ft. Looking at the generated polygons critically I'm seeing some issues. The red line in this picture is measured out to 150 ft but the polygon is far larger than what I would expect.

enter image description here

These screenshots show my settings in ArcGIS Pro which I imagine illustrate the proper setup of this service area. enter image description here

enter image description here

What could be the issue I am overlooking here?

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  • I'm not familiar with this tool, but it may be worth checking that your data is projected and is in a projection that is good for calculating distances.
    – Baltok
    Apr 28, 2021 at 19:19
  • Current projection: NAD 1983 StatPlane (which is commonly used for distance calculations as far as I am aware)
    – Therow
    Apr 28, 2021 at 20:21
  • Yep, you should be good to go. Methinks, the devil is in the tool settings then.
    – Baltok
    Apr 28, 2021 at 20:33
  • I'll edit the main post with an update. Still not resolved.
    – Therow
    Apr 29, 2021 at 21:00
  • I'll be breaking down my network into simple components to test a few more troubleshooting methods but does anyone know if using a 'zero' cutoff would be helpful?
    – Therow
    Apr 30, 2021 at 14:07

1 Answer 1

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The polygon that was generated in the above scenario looks more like the red outline in this screenshot example (I forgot to bookmark this use-case for future evaluation).

enter image description here

The issue appears to be the difference between standard precision and high precision. I knew that standard precision was less precise but I didn't expect it to be double to three times as large as it should be. I mean, 1.2-times larger is a far more acceptable tolerance than 2-3 times larger and it makes me wonder if there indeed exists issues within ArcGIS PRO's calculation of service areas and optimization efforts.

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