The ArcGIS Utility Network (UN) serves as a system of record for the assets of a utility, in many ways similar to its predecessor, the geometric network. While a UN and a geometric network can serve the same basic purpose of modeling utility assets, a UN is much more powerful, complex, and widely accessible. One advantage of the ArcGIS Utility Network is that it allows users to represent and model their assets in a more “real world” fashion. The UN is broken down into a structure network, and one or more domain networks. When a UN is built, a set of feature classes are created that model the structural features which support your utility. These features classes together are called the structure network. The structure network does not have any resources (such as water) flowing through it, but instead contains those assets that support resource flow. The structure network is a key component to manhole configuration in sewer and stormwater UN.
Manhole configuration in the UN is driven by ArcGIS Arcade attribute rules. Attribute rules are user-defined rules that enhance the editing experience and enforce data integrity. Using attribute rules, we can more accurately model manhole configuration in the UN. There are two attribute rules that are included in both the Sewer and Stormwater Utility Network Foundation solutions offered by Esri.
1. Create Manhole Channel: This attribute rule is set on the Sewer Storm Vault – Manhole feature in the Structure Junction feature class.
2. Line – Snap to Manhole: This attribute rule is set on the Sewer Line feature class for all subtypes.
This first rule creates the manhole channel feature in the domain network that is associated with the manhole feature in the structure network. With this rule enabled, if a user creates a Sewer Storm Vault – Manhole, the Sewer Device Manhole Channel feature is created coincidentally. Using a containment association, the Manhole Channel is contained by the Manhole.
The Structure Junction Sewer Storm Vault represents the full structure as seen in the image on the left. The Sewer Device Manhole Channel represents the channel, where the gravity mains meet. By making use of the two attribute rules discussed, manholes are modeled in a much more realistic way in the Utility Network.
The second rule is triggered when the sewer line, typically a gravity main, is snapped to the manhole channel feature. Note that the line can only snap to the manhole channel feature, and not the vault, because the manhole channel and line are both in the domain network.
This rule generates pipe connection point features at the ends of the sewer line, offsets the line from the manhole by 2 meters, and uses connectivity associations to logically connect the pipe connection points to the manhole channel. This configuration and use of associations allows users to trace through the Manhole Channel, making the Utility Network fully traceable.
The manhole configuration in the UN is shown on the right. The dashed line represents the connectivity association between the pipe connection points, and the manhole channel. The vault and the manhole channel are stacked.
By taking advantage of the two attribute rules, users can model manhole configurations more accurately representing the real-world build, improve tracking of pipe length with the offset from the manhole, and maintain a fully traceable network.
We hope this article has provided some value to you in managing your Utility Network. If you ever need additional help, don't hesitate to reach out to our team of UN experts.