Which of the following components is NOT essential for a utility network model?

In the context of a utility network model, imagery layers are primarily used for visual context and reference rather than as integral components of the network itself. The utility network model is designed around key components that define how utilities operate, such as network edges, subnetwork definitions, and trace configurations.

Network edges are essential because they represent the physical connections between different components of the utility network, such as pipelines, cables, or transmission lines. Subnetwork definitions help in organizing and managing different sections of the network for efficient operation and analysis, making them crucial for understanding how various parts of the network interact with one another. Trace configurations are vital as they allow users to perform analyses to trace the flow of resources through the network, aiding in operations like maintenance and planning.

Imagery layers, while useful for enhancing spatial awareness or providing additional background information, do not directly influence the structural or functional aspects of the utility network. Therefore, they are not a necessary component when building or functioning within a utility network model.