The Sites Project Authority which oversees the proposed Sites Reservoir, claimed on Wednesday an analysis found millions could have benefitted by the reservoir capturing water from the recent storms.

The Sites Project Authority announced findings from a new analysis that projected the Sites Reservoir could have diverted and captured 120,000 acre-feet of water in just two weeks if the reservoir had been operational from January 3-15. Based on forecasted flows, the analysis showed the reservoir would continue to capture water over the next few weeks as flows continue to run high, the authority stated. “This is exactly the type of scenario that Sites is being built for — short windows of extremely high flows. There is an untapped opportunity to capture and store a portion of the significant amount of flow from the Sacramento River that occurs during these rare but major storms without impacting the value of these high flows for our environment,” said Jerry Brown, Executive Director of the Sites Project Authority.

Sites Reservoir is specifically designed to divert and store water generated by storm events, like the atmospheric rivers that drenched the state in recent weeks, to increase water availability during drought years, the authority stated. The analysis found Sites Reservoir could have diverted 120,000 acre-feet of water — less than 4 percent of Delta outflow — from January 3 to 15, the authority stated.

Long-range forecasts estimated that Sites Reservoir would continue to divert stormwater through at least February 15, for a total 382,000 acre-feet of water, the authority stated. A single acre-foot of water is enough to exceed the average annual indoor and outdoor water use of one to two California households, according to the Water Education Foundation.

“The rainstorms that pummeled Northern California would have been Sites’ time to shine,” said Alicia Forsythe, Environmental Planning and Permitting Manager of the Sites Project Authority. “It would have captured a portion of the flood waters for use in future dry times by farms, families, and ecosystems, while leaving lots of water in the Sacramento River and Delta for our environment and fisheries.”

While Sacramento River flows began increasing in late December, the Project would have implemented its 7-day pulse flow protection criteria and not started diverting until January 3. The pulse flow protection criteria protects these initial high flow events as they provide for out-migrating salmon and river ecosystems.

Periods of heavy rainfall are ideal opportunities to divert and capture water that accumulates quickly but is often lost to flooding and rapid runoff, the authority stated. The authority added Sites won't divert any water until all other water rights and regulatory requirements are met.

The analysis showed that during major storms, all needs can be met, and Sites would still be able to store excess water while meeting the project’s protective diversion criteria.

Sites Reservoir is an off-stream reservoir designed to capture and store a portion of stormwater from the Sacramento River and release water to California communities, farms, business, and wildlife during drought years.

The authority stated the Sites Reservoir has broad statewide support from cities, counties, water agencies, and irrigation districts throughout the Sacramento Valley, San Joaquin Valley, Bay Area, and Southern California which are working together to advance the project. The Sites Reservoir Project is locally led by the Sites Project Authority which is made up Sacramento Valley water districts, cities, and counties.

Sites is an off-stream reservoir proposed north of the Sacramento-San Joaquin Delta, designed to provide water supply and environmental benefits during dry periods, especially during extended drought. Sites would be the first major storage reservoir developed in the state in decades.

Additional information can be found at or on Facebook and Twitter at @SitesProject.

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