The City of Houston is in the process of upgrading the Northeast Water Purification Plant (NEWPP) to accomplish its goal of reducing the area’s dependence on groundwater. The City also invested extensively in digital twin technologies to train and equip operators to know how to properly operate and optimize the $2Bn worth of new treatment and pumping processes. The process of training and equipping operators to appropriately control and then optimize this many new systems is intense, and the benefits of digital twins have been invaluable. One of those digital twin platforms is focused on helping operators operate the pumping systems optimally. The new plant includes 26 new raw, transfer and high service pumps totaling almost 40,000HP. Some of these pumps are on VFD and some are not. One of the most challenging aspects of running all of these pump correctly is the complexity of the extended commissioning cycle. The plant expansion includes essentially two new treatment plants that were commissioned approximately 3 years apart from each other. In the meantime, suction and discharge conditions that the pumps actually see have been different than the ultimate design for the campus. The digital twin platform was used for multiple purposes during the commissioning of all of these systems. First, operators were adequately trained both on the fundamentals of how centrifugal pumps work, and on the complexities associated with operating some pumps on VFDs and some at constant speed. Next the system was used to assure that all instrumentation was correctly installed, calibrated and scaled. Finally, the system was used to optimize operations to actual conditions and not just to design conditions. This final step alone paid for the entire digital twin platform by identifying an optimal operating scheme that reduced the high service pump energy consumption by 700HP (19%). Lost efficiency must go somewhere per the laws of thermodynamics. This 700HP of inefficiency was being transferred to heat, damage and noise; none of which is good for the equipment. By identifying and rectifying the inefficiency, Houston’s operators reduced the facilities electrical expenditures, but also prolonged the life of this very expensive equipment. That is good for the plant, good for the rate payers of the City of Houston, and good for the environment. This presentation will show how digital twins enable water and wastewater operators to do their jobs better by providing them with valuable real time insights. As treatment plants and pumping systems become more complex, these essential tools will continue to prove their value to those that design, operate and manage our critical infrastructure.