topic Re: Weird service areas in ArcGIS Network Analyst Questions

Weird service areas

LizGoldman1 — Thu, 16 May 2013 19:20:22 GMT

Hi All - I am trying to create service areas for a rural area. Blocks that are completely surrounded by a service area are filled in, while those that are not completely surrounded are left out of the service area (except for the search distance). Is this normal? Is there a setting that will prevent the blocks from being filled in? Or that will have them filled in if they are mostly covered by the service area? I want to make sure things aren't being over represented and also that the map is consistent.

Thanks in advance for your help!

Re: Weird service areas

JaySandhu — Thu, 16 May 2013 20:36:33 GMT

Service area polygons cover the street lines that can be reached within the specified distance or travel time break value.
It's goal is not to cover blocks.

What settings are you using? From the screen shot it looks you have set a very small trim distance that is causing the service area polygons to be trimmed to within a few meters of the outer set of street lines. Perhaps that is causing the "weird" shapes that you are seeing.

Jay Sandhu

Re: Weird service areas

LizGoldman1 — Fri, 17 May 2013 12:12:42 GMT

Hi Jay - Thank you for responding to my post. You are right, my polygon trim was set to 100 meters. Is there is typical trim distance that people use?

Re: Weird service areas

MáireMc_Namee — Wed, 31 Jan 2018 22:32:32 GMT

I know this is quite old, but did you ever get a solution? I am having this problem now too where networks that are completely linked are filled in.

Re: Weird service areas

JoeBorgione — Wed, 31 Jan 2018 23:41:54 GMT

Let's get Jay Sandhu‌ to weigh in on this again, but perhaps you could provide more details (like screen shots) of your problem. While I'm not as active in NA as I used to be, it's been my experience that service area polygons are more of a guideline than a hard, fast boundary. What really matters is how the routes themselves show up as the service area.

Re: Weird service areas

JaySandhu — Wed, 31 Jan 2018 23:58:57 GMT

What software/version are you using and what settings are you using for the service area. As Joe mentioned, post a picture of a problem and that might help figure out change in settings.

Jay Sandhu

Re: Weird service areas

MáireMc_Namee — Thu, 01 Feb 2018 00:22:33 GMT

I started a new discussion here https://community.esri.com/thread/208963-service-area-polygon-appears-to-fill-in-between-the-roads-for-areas-it-should-not-reach

Thanks!