Network Analyst Closest Facilities

Ndow

I have a user that does closest facility routing for our 911 Fire agencies and EMS agencies. She created a map for fire than did a save as and created a map for EMS off the previous map. She noticed that when she updated the facilities for closest facilities in the EMS map it updated it in the Fire map as well. When working with networking analyst and closest facilities is it possible for that information to be linked between maps even if the maps have different names. 

VenkataKondepati

Yes, it is possible for the closest facility information to be linked between maps, even with different map names, if both maps reference the same underlying Network Analysis layer.

Why This Happens
When your user performed a "Save As" on the original Fire map to create the EMS map, the new map file often retains a pointer to the original Closest Facility Network Analysis layer. The Facilities (inputs) are stored within that single analysis layer. When she edits the Facilities in the EMS map, she is editing the shared analysis layer, causing the change to appear in the Fire map as well.

How to Fix It
To prevent this, the user must create a completely new, independent Closest Facility layer for the EMS map instead of editing the copied one. This ensures that the two maps have separate network analysis objects and facility inputs.

Would you like the steps on how to create an independent Network Analysis layer in ArcGIS?

 

That's a very common and often confusing behavior when working with the Network Analyst extension in ArcGIS Desktop (like ArcMap or ArcGIS Pro).

The short answer is yes, it's absolutely possible for that information to be linked between different maps, and it's by design—depending on how the facilities were added.

Here is an explanation of why this happens and how you can prevent it.

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You can also try.

To ensure the Fire and EMS maps can have independent facility lists, the user needs to create a brand new, independent Network Analysis layer for the second map (the EMS map).

Instead of using "Save As" on the map document and then editing the existing Closest Facility layer, follow these steps for the EMS map:

1. Open the EMS Map.

2. Remove the Existing Closest Facility Layer (the one that is linked to the Fire map).

3. Go to the Network Analyst toolbar (or Analysis ribbon in Pro).

4. Click the Network Analyst drop-down menu and choose New Closest Facility (or use the tool in the Geoprocessing pane).

5. This action generates a completely new and unique Closest Facility layer with its own independent Facilities sublayer.

6. Add the Facilities to this new, independent layer.

Now, updating the Facilities in the new EMS Closest Facility layer will not affect the original Closest Facility layer in the Fire map, as they are separate network analysis objects.