Attribute Rule failing on Manhole creation in Stormwater

[LindseyStone]

I've just deployed the Stormwater Utility Network and have been testing and I noticed that every time I try to add a manhole I get this error.  I disabled the Structure-Junction - Create Manhole Channel attribute rule for the time now,  but it would be nice to know how to fix this.  I'm looking at the activevol field in devices subtypes and that isn't even a field being utilized as it has domain set up to it.  Also, can someone explain to me why the thought process of having the manhole structure Junction,  a Pipe Connection Device, and a Manhole Channel Device all at this location is necessary.  Seams like a lot.

I've also found that I get an error message when utilizing the template BMP Boundary with centroid BMP Boundary with in the Editor map of the provided Pro Package with an association error message.

[MikeMillerGIS · Accepted solution]

The pipe connection and/or manhole channel that the rule is creating requires a value for active volume.  So you can either make the field nullable(and adjust the network attribute), or adjust the rule to include a value in the return edits.  We could also define a default value on those subtypes in the data model.  That might be the easier fix.  

[PatrickGCowan]

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Also, can someone explain to me why the thought process of having the manhole structure Junction,  a Pipe Connection Device, and a Manhole Channel Device all at this location is necessary.  Seams like a lot.

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This containment model provides a more accurate representation of a manhole and its internal components. A manhole is essentially a vault—a structure that contains other elements. In our model, the Manhole Vault is represented by the structure junction, which contains both pipe connections and a manhole channel.

Pipes entering a manhole do not connect to a single central point; they connect at the edges of the manhole. A typical manhole is about 4 feet in diameter, so attribute rules offset pipe connections by approximately 2 feet in either direction to reflect this reality. These pipe connections use associations with the manhole channel to create the link between them. Conceptually, the channel is a line across the bottom of the manhole, but we model it as a point because in some cases it must act as a controller in the Utility Network to model flow—and a controller cannot be a line.

This modeling approach also enables accurate 3D representation of each pipe connection’s elevation, which is critical for depicting slope and flow through the manhole. This level of accuracy is important for hydraulic modeling and maintenance planning, where precise elevation and flow control can impact system performance and operational decisions.

Below is a top-down diagram to help visualize this structure:

We understand this seems complex. For simplicity, we are developing a Stormwater Essentials model, which uses a single point to represent the manhole and connects pipes directly to it (to be released early next year). This approach is similar to what people were used to in the geometric network. While it is easier to understand, it is less accurate for detailed analysis. Ultimately, choosing which manhole model to use will be a business decision: do you need high accuracy, or do you need simplicity?

[LindseyStone]

@MikeMillerGIS defining a default value on the subtype Manhole Channel fixed this attribute rule issue and now it Runs.  Thank you for that suggestion.

@PatrickGCowan thanks for the more detailed explanation.  My Civil Engineer has stated he wants all the elevation data in it so it looks like the higher accuracy is the direction I most likely would need to look towards.

Another question on the attribute rules when it applies to the Manholes.  Within the Manhole it has Rim Elevation, Invert Elevation, and Depth.  I'm seeing if I update the Z value on the Manhole it updates the Rim Elevation & Invert Elevation on the Manhole, the Z elevation on Manhole Channel, the Z elevation on associated Pipe Connections and Pipes,  along with the elevation on the pipe.  I'm loving all the places it automatically fills out.  But my questions are:

1. Why does it fill out the Rim Elevation  wouldn't this be different than the invert elevation as the rim is at surface level?  Otherwise your depth will always be 0.  I would think this would just be manually entered as an additional value just in the attribute table.

2. What happens if the Pipes are different heights within the Manhole Channel.  I know this is common in Sanitary Sewer to have drop manholes,  didn't know if this was a thing too concerning in Strom Sewer.

Thanks again!