President Trump dived headfirst into one of California’s most contentious fights Friday, signing a memorandum intended to divert more water to farmers and “reduce regulatory burdens” that include protections for endangered species and environmental laws.

Senior officials in the Trump administration said the memo allows for speedy environmental reviews of major water projects in the West, including the federally operated Central Valley Project, and will cut federal regulations that get in the way. Trump called for strict timelines to ensure more water makes it to farmers.

Trump’s memo directs his interior and commerce secretaries to streamline regulatory processes and remove “unnecessary burdens” and develop a timeline for completing compliance requirements for major water projects.

“This will move things along at a record clip,” Trump said after signing the memo in Arizona alongside California GOP Reps. Kevin McCarthy, the House majority leader, and Devin Nunes, David Valadao, Jeff Denham and Tom McClintock. All represent Central Valley districts with substantial agricultural interests.

“And you’ll have a lot of water. I hope you’ll enjoy the water you’ll have,” Trump said.

Trump signed the memo less than three weeks before midterm elections in which several California Republicans are locked in competitive races, including Denham of Turlock (Stanislaus County), Valadao of Hanford (Kings County) and Nunes of Tulare. After signing the memo, Trump handed his pen to Nunes, the House Intelligence Committee chairman and one of the president’s most loyal defenders in Congress.

Trump and California Republicans have pledged to fight what they call burdensome regulations to increase water supplies for Central Valley farmers. In August, as wildfires were raging across the state, the president tweeted that Gov. Jerry Brown should allow the “Free Flow of the vast amounts of water coming from the North and foolishly being diverted into the Pacific Ocean. Can be used for fires, farming and everything else.”

Governor Jerry Brown must allow the Free Flow of the vast amounts of water coming from the North and foolishly being diverted into the Pacific Ocean. Can be used for fires, farming and everything else. Think of California with plenty of Water - Nice! Fast Federal govt. approvals. — Donald J. Trump (@realDonaldTrump) August 6, 2018

The timing of Friday’s announcement was not lost on Doug Parker, director of the California Institute for Water Resources, a University of California research organization.

“This has a lot to do with the upcoming elections and helping their base,” Parker said. “It’s a feel-good move.”

However, he said, it’s unlikely to accomplish much.

“Major changes to move water for agriculture will be caught up in courts, so this won’t likely lead to any action,” Parker said.

The Brown administration took a tepid tone toward Trump’s plan, saying there must be a balance between the needs of the environment and farmers.

“California is advancing the policies needed to improve water supply reliability and protect ecosystems,” said Lisa Lien-Mager, spokeswoman for the California Natural Resources Agency. “We can and must do both, without sacrificing one for the other. We hope we can continue working with the federal government to achieve these shared goals.”

In a statement, California House Republicans said Trump’s action would bring “immense relief for the farmers and families of the San Joaquin Valley and communities across California.”

Gubernatorial candidate John Cox also latched onto the announcement, calling it “good for Californians, our farmers and farm workers.”

Deputy Interior Secretary David Bernhardt called the directive the most significant action a president has taken on water in his lifetime. He said the memo would reduce the time devoted to planning and environmental reviews of water projects.

Bernhardt is a former partner at a lobbying firm that represented the Westlands Water District in the western San Joaquin Valley, which has long sought increased water deliveries for its largely agricultural customers.

The Trump administration has for months expressed an interest in getting involved in California’s long-standing water wars. In August, Interior Secretary Ryan Zinke issued a memo calling for more water from the Central Valley Project to go to agriculture and water contractors by streamlining the Endangered Species Act.

Environmental groups said that diversion would hurt imperiled salmon and other fish in the San Joaquin, Sacramento and Klamath river watersheds.

Peter Gleick, a noted water expert and co-founder of the nonprofit Pacific Institute, said any attempt by the administration to weaken environmental regulations and protection for endangered species would almost certainly be challenged in court.

“What they call regulatory burdens, most people call environmental protections,” Gleick said. “When they talk about speeding up environmental reviews, what they mean is silencing the voices of people who want to participate in decisions about critical water projects.”

Melody Gutierrez is The San Francisco Chronicle’s Sacramento bureau chief. Email: mgutierrez@sfchronicle.com Twitter: @MelodyGutierrez