Hydroelectric Upgrades Enhance System Flexibility
Two pickup truck-sized valves weighing 35,000 pounds each were replaced in March 2021 by Water Authority Operations and Maintenance crews at the agency’s Pressure Control and Hydroelectric Facility in central San Diego. The pressure-control facility is a key piece of the Emergency and Carryover Storage Project, which ensures water is available around the region if imported water deliveries are disrupted.
To perform the valve replacement, a large crane lifted the existing valves out of the facility through the roof and placed them onto flatbed trucks for delivery to a disposal and recycling site. The new valves were then lowered into the facility through the roof and fitted with new 42-inch pipeline sections. Concrete was poured to build pedestals that secure the valves in place. The valve installation process took four days to complete.
The hydroelectric facility pressurizes a 22-mile-long section of the Water Authority’s large-diameter Pipeline 5 between San Marcos and Mira Mesa. The pipeline previously conveyed water in one direction only -- from north to south -- by gravity. This limited the Water Authority’s ability to move water around the county in the event of a supply disruption. Upgrades to Pipeline 5 now allow water to be transported either north or south using water stored at San Vicente Reservoir, which greatly improves pipeline operations and ensures that water can continue flowing to member agencies.
“The new valves will allow the facility to function efficiently at both low and high water flows, depending on regional demand. The project is part of ongoing improvements that enhance the flexibility of our regional water delivery system. ”