Utilization of Network Subsystems for Designing a Level-1 Redundant Water Distribution Network

If some measurements of system reliability are not included, a least-cost optimization of a water distribution system (WDS) leads to a branched network. Utilizing network subsystems that provide an explicit level of system redundancy is one way to improve the performance of WDS networks. In this approach, the whole system is subdivided into two subsystem networks. Then, during the optimization phase, the two subsystems are simultaneously optimized so that each can provide some level of service to the consumer. Optimization results are ultimately determined by the pair of subsystems used. Unfortunately, there is little to no literature on the optimization of the selection of subsystems. The present study examines both the selection of subsystems and the optimization of the component sizes in designing a level-1 redundant network. Candidate subsystems are generated using graph theory where st numbering for the network is assigned first, and then the subsystems are generated following the decrement and increment orders of the node's st-numbering. The optimization problem is solved using a genetic algorithm for backup selection and linear programming to compute optimal component sizes.