Significant new water storage is finally becoming a reality in California.
In late October the U.S. Department of the Interior and the San Luis-Mendota Water Authority approved plans to implement the B.F. Sisk Dam and Reservoir Expansion Project on the west side of California’s Central Valley.
The joint project will create an additional 130,000 acre-feet of storage space in San Luis Reservoir, which is the largest offstream reservoir in the U.S. The massive project will produce additional water supply for two million people, over one million acres of farmland and 135,000 acres of Pacific Flyway wetlands and critical wildlife habitat.
The B.F. Sisk Dam and Reservoir Expansion Project is the first approval of a major water storage project in California since 2011.
The expansion project will piggyback on a seismic re-enforcement project already underway for B.F. Sisk Dam.
B.F. Sisk Dam, which is located in the Diablo Range foothills about 12 miles west of Los Banos, is a 382-foot high earthfill embankment. It’s over three miles long and impounds San Luis Reservoir, which has a current total capacity of around two million acre-feet of water.
As noted earlier, San Luis is the nation’s largest off-stream reservoir. This means almost all of the water that flows into it is diverted from natural stream or river beds.
San Luis stores federal Central Valley Project water that’s captured behind Shasta Dam and Whiskeytown Dam and released into the Sacramento River and diverted into the Delta-Mendota Canal from the Delta near Mountain House northeast of Tracy. It’s fed by excess stormwater as well as excess snowmelt from the Sierra Nevada Mountains. holds water that eventually travels further south.
The added 130,000 acre-feet of storage coming to San Luis is a significant win for California agriculture and for water storage in California.
“San Luis Reservoir has served as the hub of California’s water system south of the Sacramento – San Joaquin Bay-Delta since its completion in 1967,” San Luis and Delta-Mendota Water Authority Board Chair Cannon Michael said in a statement. “The ability to capture more water in the years it is available, particularly given California’s changing climate, is a critical component of a more secure future for the communities, farms and wildlife dependent on the Central Valley Project for their water supply,” he added.
The approved San Luis project is only one of four proposed dam projects designed to add significantly more acre-feet of water storage in California.
Those projects – building a new dam in Del Puerto Canyon in the Diablo range near the Central Valley city of Patterson, raising Los Vaqueros Reservoir and the proposed new Sites Reservoir in the Antelope Valley portion of the Coastal Range – are projected to add around two million acre-feet of new off-stream range water storage.
Believe it or not, the Sites Reservoir was first proposed in the 1950s. Presently – and finally – it is on target to be California’s next major reservoir. Construction is to start soon and it has a projected completion date of 2031. It is to be financed by a statewide water bond approved by voters in 2014.
The Sites Reservoir is designed to add over 1.3 million acre feet of storage that would be used to help supply water for up to 27 million Californians and 500,000 acres of Central Valley farmland. It also would provide water for fish needs in dry years.
The four projects combined create almost a third of the capacity now in the State Water Project that can store 5.8 million acre feet of water with the most being behind Orville Dam with 3.5 million acre feet.
The four projects are equal to almost a sixth the storage capacity of the 12 million acre foot Central Valley Water Project. Shasta Dam with 4.5 million acre feet is its biggest component.
The significance of added water storage in California for agriculture use as well as for residential and industrial use can’t be overstated in 2023. Last winter’s heavy rain and snow, most of which ended up as runoff because there was no more room to store it, is a recent and vivid reminder that excess stormwater and snowmelt from the Sierra needs to be stored for use later on. The San Luis Dam, for example, was filled to the top for the first time in many years. There was enough excess water to fill 130,000 more acre-feet (the amount the damn is to be raised) and then some.
That these projects are becoming reality (California will have drought and water shortages again despite last year’s deluge) also is helping to set a new public mindset and paradigm when it comes to water and the need to store more of it. Increasing food prices at the grocery store also is playing a role in this as consumers remember that food comes from farms and farmers need water to produce crops.
Water is essential for growing food and the ability to store more water is essential for California agriculture. Now it’s time to build on these four projects and to create others that will benefit agriculture, people and industry. We’re all in it together.
My Job Depends on Ag Magazine columnist and contributing editor Victor Martino is an agrifood industry consultant, entrepreneur and writer. One of his passions and current projects is working with farmers who want to develop their own branded food products. You can contact him at: victormartino415@gmail.com.
