Gray Davis became governor in 1999 and one of his first acts was to decree that there would be no major changes in water policy for eight years, which he assumed would be his two terms in office.

Davis, a veteran politician who had climbed the political ladder one rung at a time, was well aware of the decades-long stalemate on the fundamental issue of how water should be apportioned between farmers and flows to support fish and other wildlife. He was also notoriously averse to political conflict and didn’t want what had been dubbed “water wars” to be rekindled during his governorship.

Davis was recalled five years later and the conflict continued after his departure. During Jerry Brown’s second stint as governor, from 2011 to 2019, he embraced the concept of “voluntary agreements.” If farmers would reduce diversions from the Sacramento and San Joaquin rivers and their tributaries, they could avoid the mandatory cutbacks that environmental groups and their allies favored.

Gavin Newsom continued down that path after succeeding Brown. With just two months remaining in his reign and a likely presidential campaign to follow, Newsom wants to claim that he settled the perennial water conflict. It would pave the way for construction of a tunnel that would carry Sacramento River water under the Sacramento-San Joaquin Delta and into the California Aqueduct.

Last week, the state Water Resources Control Board passed a revised water flow plan, officially renamed the “Healthy Rivers and Landscapes Program,” but the agricultural stakeholders who had originally accepted the concept backed away, saying it contains too much regulation.

“It’s unrecognizable,” said Jennifer Pierre, general manager for the State Water Contractors, which represents public water agencies serving 750,000 acres of farmland and 27 million people. 

Meanwhile, environmentalists, who had never liked the voluntary agreements approach, renewed their call for more direct regulation of flows into the Sacramento-San Joaquin Delta.

“This plan fails the four million people living in the Delta, the 12 million more who live in the greater San Francisco Bay Area, and all Californians,” Barbara Barrigan-Parrilla of Restore the Delta, said. “Implementing the voluntary agreements will further diminish their economies, public health, and access to clean water.”

Thus, what Newsom would like to portray as a truce will most likely be just another chapter in an ongoing battle, probably shifting to the courts. A legal conflict would probably bring into play a question that both Brown and Newsom have wanted to avoid: whether the state’s regulation of water legally supersedes water rights, some of which date back to the 19th century.

The new policy’s already shaky viability also must contend with still another unknown — opposition from President Donald Trump’s administration. The state shares jurisdiction over water allocation with the federal Central Valley Project and the new policy is meant to cover federal water deliveries.

Through both of his stints in the White House, Trump has taken the side of farmers in their political and legal battles over water. The Feds control more water than any other player, and the U.S. Bureau of Reclamation has publicly echoed farmers’ criticism that the plan is regulatory overreach and possibly illegal.

Moreover, the plan assumes that its projects to improve water flows and wildlife habitat will be partially financed by the federal government.

That said, Trump’s presidency will end in two years and the chances of having a state-level plan finalized by then are nil, so the federal side of the water conflict will likely depend on which party wins the presidency in 2028. Thus, the success or failure of Newsom’s presidential quest — assuming there is one — could be the decisive factor in California’s water conflict.

Dan Walters is one of most decorated and widely syndicated columnists in California history, authoring a column four times a week that offers his view and analysis of the state’s political, economic,...