Pro creating routes along closed segments by jumping to nearest routable segment

[melisahansen]

When routing on the same network different results are generated between ArcMap and ArcPro. In the below images, the highlighted segment is closed for routing, however in ArcPro, it jumps to the nearest routable segment and creates a route, which is not the desired result. The same routes in ArcMap produce the following error:

“Warning: Location "Graphic Pick 2" in "Stops" is on a non-traversable network element position.

Warning: Need at least 2 valid stops.

Error: "Stops" does not contain valid input for any route.”

How can we get ArcPro to behave in a similar way to ArcMap? In route properties, the Network Locations tab, the options are not the same between ArcMap and ArcPro so finding out how to get them to behave the same is not straight forward. We can set a search tolerance in Pro, but we don’t have to do this in ArcMap to get the desired result. Any ideas?

Figure 1: Routing jumping to nearest routable segment when attempting to route to a closed segment in ArcPro.

Figure 2: Routing jumping to nearest routable segment when attempting to route from a closed segment in ArcPro.

Figure 3: Routing error as expected when attempting to route to a closed segment in ArcMap.

Figure 4: Routing error as expected when attempting to route from a closed segment in ArcMap.

[MelindaMorang]

Hello Melisa.  The behavior you're seeing in Pro is as designed.  Points will always locate on the closest routable and non-restricted point on the network according to the specified locate settings and travel mode.  In your case, the closest edge is restricted, so it locates on the next-best option.

When designing this behavior, our assumption is that there was no benefit to locating on a restricted edge or junction because this would just cause the route to fail or be unable to reach the point.  Could you tell me what you're trying to do and why you want to see the solve failure?

A couple of other things that may be useful to you (just a guess, since I don't know what you're really trying to do):

• When a point locates somewhere that isn't the closest option because the closest option is restricted, the Status field in the attribute table will be set to 7, or "Not located on closest".  If you just need to determine which points aren't located where expected, you can filter the inputs to find rows with this value.
• You might be able to achieve your goals by adjusting various locate settings, such as setting a search query, adjusting search tolerance, etc. This documentation may help: https://pro.arcgis.com/en/pro-app/latest/help/analysis/networks/locating-analysis-inputs.htm 

[melisahansen]

This is an important function to us as we use this to test areas that are not routable to public safety and many other purposes. For example, if a road is closed, we want it to fail - not jump to a near segment that does not actually have any connection or access to the closed segment. We want to know that a specific address is not routable, we do not want it to jump to a near segment and suggest routing to a non routable address via something nearby like the behavior exhibited. We also like to use this to determine sections of communities that may be impacted from proposed construction closures, floods, etc. 

[MelindaMorang]

Okay, I understand.

I think you may be able to achieve at least part of your goal by simply running the Calculate Locations tool or the Add Locations tool and checking the Status field or the network location fields afterwards.  You don't actually need to do a solve operation to determine if the points are not routable.

You can also set the Search Tolerance property to something fairly small to reduce the likelihood of the point getting snapped to another street that's far away.

Does this help at all?

[melisahansen]

Is this behavior in Pro, version specific or is this how routing was designed in all of Pro? 

[MelindaMorang]

This is how Pro was designed right from the start.