upstream trace

An upstream trace is a trace in a sink (resource flow is toward the subnetwork controller) or source (resource flows away from or exits the controller) utility network that moves against the flow of the resource. In a source network, such as gas or electric, an upstream trace moves against the flow and toward the source, such as a circuit breaker or generator. In a sink network (sewer or storm water), an upstream trace moves against the flow away from the sink, such as a sewage treatment controller.