A century of water management in the western United States is on the verge of being restructured and two UC Berkeley water experts approve.

Under a plan recently passed by Congress, the U.S. Secretary of the Interior is charged with implementing an agreement among seven states — Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming — in which each agrees to take less water from the Colorado River. The plan, more than two years in the making, now is headed to the desk of President Donald Trump for his signature.

The original Colorado River Compact was agreed to in 1922 and locked in a percentage allotment for each of the states. But with the region mired in a drought that’s lasted for two decades, that plan couldn’t survive. The new agreement, the Colorado River Drought Contingency Plan Authorization Act, easily passed both houses of Congress. Pending presidential approval, the act will see that the Lake Mead and Lake Powell reservoirs will not be in danger of having such low capacity that they can’t deliver water or produce hydropower.

On just 4.3 of the United States land mass, California is home to 12 percent of the nation’s population and produces more than 13 percent of the nation’s agricultural crops. With the state having to do with less water, the price for water will rise and scientists, including those at Berkeley, will be on the hunt for new ways to increase the amount of water that can be made available to the state.

The plan acknowledges that the flows of the Colorado River and its tributaries are declining, meaning the drinking water of 40 million people and the irrigation source for farmers and ranchers in the seven states are in jeopardy. Among those negotiating were representatives of cities, water districts, Native American tribes and farmers.

Combined storage in the Lake Mead and Lake Powell reservoirs last year reached its lowest level since Lake Powell began filling in the 1960s. As of April 10, Lake Powell’s level was at 3,569 feet, roughly 37 percent full.

Ellen Bruno, a UC Berkeley economist and a collaborator with UC Water, a group of scientists, investigators, researchers and students from eight UC campus exploring water options locally and nationally, says the plan won’t come close to restoring the river to the way it used to be, and that this was never the idea.

“This is a follow-up to the allocations that bind these states together,” Bruno says. “It’s never come to this before, to where the states felt the need to renegotiate. But there has been a realization for a while that we had to find a way to deal with the shortage. The water is oversubscribed, and we’re dealing with less water and a long drought.”

Had there not been an agreement struck by the representatives, the U.S. Bureau of Reclamation would have imposed restrictions on water use.

David Zilberman, a professor in Berkeley’s Department of Agriculture and Resource Economics, couldn’t be a bigger fan of the law, saying, “I love it. The thing is, climate change is real, and the reduced water in the Colorado is a reaction to that. We need to adapt to having less water, and now we don’t have to fight over it.”

During the past years, representatives from the lower Colorado River basin (Arizona, California and Nevada) and the upper basin (Colorado, Utah, New Mexico and Wyoming) worked on drought plans separately, then came together for a final agreement. Experts had predicted that the water levels for Lake Mead and Lake Powell would become critical as soon as 2021.

The heavy rains over the past few months have left a snowpack in its wake that, researchers say, will stave off an emergency.

Zilberman says that while farmers will have to pay more money for water, this just may be the push those in the agriculture trade need to make changes. California farmers, in particular, could cut back on rice, which is a water-intensive crop, they could learn to recycle water and they could abandon traditional irrigation in favor of drip irrigation, which uses much less water.

“Farmers will say it’s not great,” Zilberman says, “but a lot of them use a lot of water. That’s just the reality of adapting to climate change. There are places with more challenging conditions than we have here. In Israel and in Australia, they have much less water than California, and they do well with what they have.”

He also expresses hope that this bill will spark a technological solution to the state’s water problems. Desalinization of sea water works, but is extremely power-intensive.

“In my view, the state needs to spend money on invention, in this case on better ways for desalinization,” Zilberman says. “San Francisco imports water from the Sierras. That’s crazy. We have all this water around us here. We have to think big, and if we do, if we adapt to the situation, we can solve this with solar power and desalinization.”