Trace Behavior in Pressure Tier

Question

Hello Community,

I'm seeking assistance with Pressure tier trace behavior.

Network Context: My network schema represents part of the water distribution system. Different colors symbolize distinct pressure zones. Our pressure controllers are pumps and storage tanks.

Problem Description: I'm running an Isolation trace in the pressure tier from the green starting point. The trace highlights sections of the network that appears to be isolated (depressurized).

However, in my opinion, the trace results are inconsistent with my network's operational logic. My expectation is that the other pressure zones that receive pressure from storage tanks Strg-16 and Strg-17 (defined as controller), should remain pressurized.

Thank you in advance!

RobertKrisher · Answer

Please log an issue with support for this so you can get attached to the bug.

RG2 · Answer

It appears this issue is related to BUG-000170530.

I was able to reproduce the same behavior in the Naperville model using a simplified structure. Pumps and tanks are configured as pressure-tier controllers, yet the isolation trace incorrectly returns features from adjacent subnetworks.

The trace was executed using the default configuration, with the Isolating category set as the filter barrier.

This behavior was observed in ArcGIS Pro versions 3.3, 3.4, and 3.5 using Utility Network versions 6 and 7 with a file geodatabase, as well as in ArcGIS Enterprise 11.3 with Utility Network 6. In all cases, the trace fails to stop at pressure-tier boundaries.

A possible workaround is to include Subnetwork Controllers as filter barriers in the trace configuration. While this does help prevent the trace from crossing into adjacent subnetworks, it's not clear whether this approach is effective in all isolation traces situations.

RG2 · Answer

Hi Robert, thanks for your help.

Yes, the pumps are configured as subnetwork controllers for the pressure tier.

The filter barrier used in the isolation trace is based on the Isolating category. I also tested using System Valve directly, and the results were the same.

The system valves do have the Isolating category assigned, and they are treated as isolating devices in the trace configuration.

As shown in the image below, the trace results include features located in a different pressure zone — but those features are still receiving water from tanks located in the previous pressure zone (defined as pressure controllers).

What’s also strange is that the trace skips the section of the network that contains the starting point, then continues selecting features beyond the next controllers that define the following pressure zone.

If I run the trace only to detect the isolation valves, it correctly identifies the valve located upstream from the starting point. The issue appears when I ask the trace to also include the isolated features — that’s when it crosses into the next pressure zone.