California has been pummeled by the worst drought on record for three years, and the blows just keep on coming.

In mid-January, Gov. Jerry Brown declared a statewide drought emergency in response to dwindling water supplies and continued lack of rain and snowfall. Now, state water officials have announced the faucet on state reservoirs would be shut to local agencies.

“The harsh weather leaves us little choice,” Mark Cowin, director of the California Department of Water Resources, said in a statement. “If we are to have any hope of coping with continued dry weather and balancing multiple needs, we must act now to preserve what water remains in our reservoirs.”

The move means the 29 agencies dependent on the California State Water Project will have to rely on overextended groundwater supplies and similarly strained resources to provide about 25 million people with water and irrigate about 750,000 acres of agricultural land.

“A zero allocation is catastrophic and woefully inadequate for Kern County residents, farms and businesses,” Ted Page, president the Kern County Water Agency's board, said in a statement, as reported by the Associated Press. “While many areas of the county will continue to rely on ground water to make up at least part of the difference, some areas have exhausted their supply.” Kern County lies at the southern end of the California Central Valley.

In fact, at least 17 communities could face severe water shortages is less than four months, according to the AP.

While California might be in the vanguard of states with their fists up against drought, it’s far from alone. Portions of 11 states were declared federal disaster areas last month, including Nevada, Colorado, New Mexico, Utah, and Idaho. Texas, Oregon, and Hawaii are also on the list. But Southwestern states differ in that in addition to regional drought they must also contend with a morass of complicated water-sharing agreements and the diminishing Colorado River.

In the Southwest, a Gordian knot of water rights, which was formed on the assumption that there would always be the same amount of water to go around, proves difficult to untie to meet new realities. At the same time, efforts to stanch increased demand for water have been scant. There’s some indication that this drought might be the impetus for long needed change.

“The era of big water transfers is either over, or it’s rapidly coming to an end,” John Entsminger, the senior deputy general manager of the Southern Nevada Water Authority, told the New York Times last month. “It sure looks like in the 21st century, we’re all going to have to use less water.”

Entsminger wasn’t speculating. He spoke in response to a U.S. Bureau of Reclamation decision to lower the flow of water from Lake Powell into Lake Mead—a first of it’s kind measure that will affect the amount of water available to cities and farms from Las Vegas to Los Angeles.

The decision still allows lower Colorado Basin states and Mexico to draw their full allotment of water—at least for now. Bureau officials believe there’s a 50 percent chance that that water will need to be rationed to those states as early as next year, according to the Times.

Agencies such as the newly formed National Drought Resilience Partnership stand ready to coordinate federal drought response and help communities grapple with water woes. But it remains unclear how states might react to an unprecedented rationing and if the many far-flung and patchwork water agreements will hold up to the stress.

As the quote often (and unverifiably) attributed to Mark Twain says, in the West “whiskey’s for drinking and water’s for fighting over.”