WASHINGTON (AP) — Tom Brundy, an alfalfa grower in California’s Imperial Valley, thinks farmers reliant on the shrinking Colorado River can do more to save water and use it more efficiently. That’s why he’s installed water sensors and monitors to prevent waste on nearly two-thirds of his 3,000 acres.

But one practice that’s off-limits for Brundy is fallowing — leaving fields unplanted to spare the water that would otherwise irrigate crops. It would save plenty of water, Brundy said, but threatens both farmers and rural communities economically.

“It’s not very productive because you just don’t farm,” Brundy said.

Many Western farmers feel the same, even as a growing sense is emerging that some fallowing will have to be part of the solution to the increasingly desperate drought in the West, where the Colorado River serves 40 million people.

“Given the volume of water that is used by agriculture in the Colorado River system, you can’t stabilize the system without reductions in agriculture,” said Tom Buschatzke, director of the Arizona Department of Water Resources. “That’s just math.”

The U.S. Bureau of Reclamation is looking at paying farmers to idle some fields, many in the vast Imperial Valley in California and Yuma County in Arizona that grow much of the nation’s winter vegetables and rely on the river. Funding would come from $4 billion set aside for Western drought aid in the Inflation Reduction Act.

Federal officials and major irrigators have been negotiating for months. Neither side has disclosed details of the negotiations or said how much money is being sought or offered.

U.S. Sen. John Hickenlooper, a Colorado Democrat, said fallowing has to be on the table. The challenge is figuring out fair payments when farmers work land of varying quality and plant crops of varying value, he said.

“Water in certain parts of the Colorado River basin is worth more than water in other parts. And somehow the Bureau of Reclamation has got to address that in a way that is fair, or at least perceived to be,” Hickenlooper said in an interview.

Agriculture uses between 70% and 80% of the Colorado River’s water, and ideas for reducing that have long been contentious. Farmers and the irrigators who serve them say their water use is justified since nearly the entire country eats the produce grown in the region, as well as meat from cattle fed on the grasses grown locally.

Water officials from cities and other states with less demand from farms say agriculture’s large take from the river allows wasteful farming practices to continue even as water grows scarcer. They note that Western water law, which gives preference to more senior users, allows farmers with those rights to grow thirsty crops in converted desert even as key reservoirs fed by the Colorado dip to all-time lows.

Tina Shields is water manager for the Imperial Irrigation District, and advises farmers to first save water through efficiencies like drip irrigation, choosing less water-intensive crops and using water sensors to cut waste. But she acknowledged that fallowing will have to be part of the equation as states heed a call by the federal government to cut their use by 15% to 30%.

“As much as we don’t like fallowing,” Shields said, joking that the practice is known as the “F-word down here,” she said some amount will be needed to conserve the additional 250,000 acre-feet of water the district has said it would save — or roughly 8% of its allotment from the Colorado River. (An acre-foot of water is enough to submerge one acre of land with a foot of water and roughly how much two to three U.S. households use per year.)

In the Imperial Valley, leaving fields idle to save water isn’t a new idea.

For 15 years, Imperial Irrigation District ran fallowing programs as part of a historic water transfer deal it cut with San Diego in 2003. The programs expired in 2017. Nearly 300,000 acres of farmland were fallowed, conserving 1.8 million acre-feet of water and costing $161 million in payments to farmers, the district said.

The Colorado River is in worse shape now, but in Imperial Valley, memories of that program linger. And farmers want far more than they were paid back then.

Larry Cox, who has grown produce and grasses in the Imperial Valley for decades, said he idled a few hundred of his 4,000 acres back then. He used the payments to buy sprinkler pipes and other equipment to make his irrigation systems more efficient. But he also let go between 5% and 10% of his workforce of irrigators, farm hands and tractor drivers.

Today, he worries about the effect of fallowing on rural communities. Besides the potential economic losses to farmers, the businesses that supply them with tires, fertilizer, gas and other needs are affected.

“It damages our community as a whole,” he said.

Many farmers also fear that once land is taken out of production, it won’t be farmed again. Part of the fear comes from how water rights work in the West, but also because fallowing can degrade soil quality and make it difficult to return the land to production later.

Paul Brierley, executive director of the Yuma Center of Excellence for Desert Agriculture at the University of Arizona, said disrupting farm operations has downstream effects.

“Farming is just like any other business,” Brierley said. “They’ve got capital invested, they’ve got employees, they’ve got markets for their products. You can’t just farm part of the time and not the rest.”

A failed proposal from Yuma County farmers last year showed how difficult it may be for federal officials and the farmers they’ve targeted to reach a deal. In that case, the farmers proposed the government pay them around $1,500 per acre-foot of water not used for four years, but the deal went nowhere.

A measure of how much Reclamation is willing to pay came in a separate offer made to farmers in Lower Basin states — Arizona, California and Nevada — for $400 per acre-foot.

Buschatzke said farmers in Arizona felt even the $1,500 offer was lower than they deserved based on what they make on the produce — let alone how important it is to consumers, he said.

“It is certainly a business, but they also see it as doing a lot of good for the entire nation with what they grow out there in Yuma,” Buschatzke said.

Since farmers in Imperial Valley hold senior rights to Colorado River water, mandating water cuts there is almost impossible without inviting litigation.

“We can’t make our growers participate,” Shields said. “We have to provide them with a business decision.”

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