Enhanced Aqueduct Operations and Reduced Energy Costs
The Water Authority’s Pressure Control and Hydroelectric Facility, located in the Mira Mesa area, serves an important function in improving aqueduct operations and enhancing the flexibility of the Water Authority’s extensive water delivery system. Several large-diameter valves within the facility control the pressure and quantity of water delivered to surface water storage reservoirs and water filtration plants located in eastern and southern parts of the county. A hydroelectric turbine generates supplemental electricity that reduces the Water Authority’s energy costs while supplying surplus power to the region.
Improved Pipeline Operations
The $21 million facility was completed in 2007 and is a partially buried concrete and masonry structure that stands approximately 18 feet above ground and is 40 feet wide and 105 feet long. 3,000 feet of 96- and 108-inch-diameter pipe connect the facility to existing pipelines in the Water Authority’s delivery system.
The Pressure Control and Hydroelectric Facility pressurizes a 22-mile-long section of the Water Authority’s Pipeline 5 between San Marcos and Mira Mesa. Pipeline 5 is a 108-inch-diameter pipeline that conveys imported water in one direction only, from north to south, by the force of gravity. This limits the Water Authority’s ability to move water around the county when imported supplies are disrupted. Enhancements to the pipeline system, including control valves in the facility, a new pump station at San Vicente and the San Vicente Pipeline, now allow Pipeline 5 to transport water either north or south using water stored at the San Vicente Reservoir, improving pipeline operations and keeping water flowing to member agencies.
Hydroelectric Energy Generation
The high-pressure flows in Pipeline 5 provide an opportunity to generate a clean renewable energy resource for San Diego County. The 4.5-megawatt turbine generator in the facility operates year-round, reducing the Water Authority’s energy costs and supplying surplus power.
The amount of clean energy produced is equivalent to the annual energy needs of approximately 1,600 households. This use of hydroelectric power instead of fossil fuels helps cut approximately 200 tons of sulfur dioxide and nitrous oxide emissions annually.