Pacheco Reservoir Expansion Project
The project would establish a new dam and expanded reservoir on the North Fork of Pacheco Creek that could hold 140,000 acre-feet of water, a substantial increase from the 5,500-acre-foot operating capacity of the existing reservoir. Constructed in 1939 and used for groundwater recharge, the reservoir is located about 13 miles southwest of San Luis Reservoir, off Highway 152.
The California Water Commission awarded the Pacheco Reservoir Expansion Project $484.55 million under Proposition 1, the water bond approved by voters in 2014 to fund new dams and water storage projects in California. This grant represents the full amount that was requested by a partnership of the San Benito County Water District, Santa Clara Valley Water District, and Pacheco Pass Water District.
The grant will fund half of the total estimated cost of $969 million for expansion of the Pacheco Reservoir, a much-needed project that will improve the long-term water supply of the northern San Benito County region. Federal grant funding will also be applied for, and the remaining costs will be covered through local water sales over several decades. The District anticipates a 2.5% – 10% participation rate for San Benito County’s share of the project.
The Pacheco Reservoir Expansion Project is a modern solution to the age-old challenges of providing a sustainable water supply for our expanding population and businesses. The project will reduce the frequency and severity of water shortages, provide flood protection for disadvantaged communities, as well as protect and grow the native steelhead population.
Among the expected benefits of the Pacheco Reservoir Expansion Project are the following:
- Increase reliability of imported water supplies to San Benito and Santa Clara counties
- Provide an emergency water supply to San Benito and Santa Clara counties
- Reduce flood risks for communities along Pacheco Creek and the Pajaro River as it flows through Watsonville
- Improve opportunities for water transfers through San Luis Reservoir
- Improve water quality, reducing taste and odor problems that result from seasonal algae blooms in San Luis Reservoir
- Increase suitable habitat in Pacheco Creek for the federally threatened South Central California Coast steelhead
- Develop water supplies for the environmental needs of wildlife refuges to support habitat management in the delta watershed
- Provide additional water for groundwater recharge
- Increase operational flexibility of water supplies at San Luis Reservoir