Raising the dam adds 500 acres to the reservoir surface area and increases capacity to approximately 242,000 acre-ft
In keeping with our strategic focus on infrastructure, Parsons in a joint venture (JV) is managing construction of the San Vicente Dam Raise Project. This largest component of the fourth and final phase of SDCWA's $1.5 billion Emergency Storage Project (ESP) creates new emergency water storage and pipeline connections to deliver water if a disaster disrupts the imported water supply. The ESP, which has been under development for more than a decade, is a system of reservoirs, pipelines, and other facilities that work together to store and move water around the county in the aftermath of a disaster such as an earthquake. When complete, the entire ESP system will provide more than 90,000 acre-ft of additional local water storage capacity, enough to supply the region for up to 6 months. This new emergency storage includes 52,000 acre-ft in the expanded San Vicente Reservoir. The dam raise will also create an additional 100,000 acre-ft of “carryover storage” for use in times of drought, bringing the total San Vicente Reservoir expansion to 152,000 acre-ft.
World’s Tallest Roller-Compacted Concrete Dam Raise
The San Vicente Dam Raise Project is the tallest dam raise in the United States and tallest roller-compacted concrete (RCC) dam raise in the world. This project elevates the existing 220-ft-high dam by 117 ft and more than doubles reservoir storage capacity—the largest single increase in water storage in the region’s history. When complete, the additional storage will bring the reservoir’s total capacity to 242,000 acre-ft. An acre-ft is 325,900 gallons—enough to meet the needs of two average families of four for a year.