Lessons Learned from the Commissioning of a 21,000 HP Pump Station in San Diego

In 2000 the San Diego County Water Authority commenced construction of the Emergency Storage Project which is a system of reservoirs, interconnected pipelines and pumping stations designed to make water available to the San Diego region in the event of an interruption in imported water deliveries. Part of the Emergency Storage Project was the construction of the San Vicente Pumping Facilities capable of moving up to 200 million gallons per day from the San Vicente Reservoir to the Water Authority's water delivery system. The San Vicente Pumping Facilities, designed by Black and Veatch and MWH, were completed under two separate contracts: 1) Pre-procurement of major equipment and 2) Construction of the facilities. On March 25, 2006, the San Diego County Water Authority awarded Gierlich -Mitchell, Inc. with the procurement, delivery and commissioning, including but not limited to, three horizontal centrifugal pumps, three 7,000 HP Induction Motors, three pump control panels and programming, and two Medium Voltage Variable Frequency Drives and transformers. Shortly after, on November 30, 2006, the Water Authority awarded Kiewit Pacific Co., with the construction of the facilities, which included the San Vicente Pump Station and San Vicente Surge Control Facility. Construction of the facilities included: the pump station building; hydraulic systems; cooling water systems; primary power service and switchgear systems; excavation and construction of a three million gallon pre-stressed concrete surge tank; over 3,000 feet of large diameter pipe ranging from 84 inch to 102 inch; and installation of all pre-procured major equipment. Early on it was clear to all parties involved that the commissioning of this new facility would be complex and challenging; spanning multiple contracts and specialties, and its successful operation would be completed as a result of identifying potential issues early, communicating with all parties involved and maintaining a common goal. Typical of many new facilities, especially those with pre-purchased equipment, the phases of construction and commissioning became overlapping and blurred. As a result, the Water Authority recognized the need to coordinate startup and commissioning meetings early on in the construction phase to define the roles, responsibilities, and most importantly, to discuss the details of the required deliverables of all parties involved so all programmers, suppliers and contractors had the same understanding of the work which needed to be accomplished. One of the more difficult challenges was the integration of multiple programs, I/O signals, and communication protocols across the Human Machine Interface (HMI), master Programmable Logic Controllers (PLC), individual Pump PLCs, and various other signal sources communicating over MODBUS, Foundation Field Bus, Ethernet, Control Net, Analog, etc. As with many projects that span a five year time period from design to completion, the technical assumptions, supporting technologies, and operating conditions can evolve, redefining the acceptance criteria for successful commissioning. As a result it was critical that the commissioning team stay committed to the facilities operational goals while considering multiple technical solutions to issues that would arise during testing.