The ongoing drought across the American West is — in some places — the worst in more than 1,000 years. Conditions are dry from California all the way to the Gulf Coast of Texas.

In a region that depends on water from reservoirs, the lake levels in many of them are shockingly low.

In South Texas, for example, along the lower Rio Grande, two reservoirs supply water to both sides of the border. For the past few years, they’ve struggled to remain even half-full. And right now, one of them – Falcon International Reservoir — is just 15% full. 

That’s scary news for farmers in the region who grow sugar cane, cotton, citrus and a whole host of other crops.

Driving between rows of sugar cane on his farm in San Benito, Texas, farmer Sam Simmons said this year’s crop isn’t in great shape. He got out of his pickup to demonstrate.

“There’s basically a section of cane that grows every about 10 to 14 days,” he said pointing to a sugar cane stalk with yellowing leaves. “The length of it is according to how much moisture there is.”

He said during a normal year, the sections — called barrels — might be six to eight inches long. 

“But we didn’t have enough moisture to really keep it growing rapidly,” he said as he pointed to a plant nearby where the barrels are less than half the length they should be. “That’s probably three [inches]. Some of those are three. This might be three and a half.”

That means this cane will produce significantly less sugar. “This field normally should produce around 40 tonnes of raw sugarcane,” Simmons said.

In a normal year, he guesses that’d translate to about 8,000 pounds of sugar. But this year, he said if he were a sugar buyer making an offer, it’d be for a lot less.

“I wouldn’t offer more than about 5,000 pounds,” he said. “So it’s probably 40% off, and that I can basically say, is due to lack of irrigation water.”

“Pray for rain” has always been a common refrain in this part of the country. Farmers can’t control what comes from the sky but until recently, water coming out of reservoirs along the Rio Grande has made up the difference. 

That’s by law — specifically, a treaty with Mexico from 1944. Simmons said his sugar cane is currently suffering because the Mexican government isn’t keeping its end of the bargain.

“The real fight is with Mexico, them providing and living up to the treaty obligations,” he said.

The treaty Simmons is referring to requires Mexico to deliver to the United States enough water to make up for the lack of rainfall on about 100 farms the size of his every year, on average. 

“But the way that it’s interpreted and the way that it’s enforced is they basically have five years,” said Brian Jones, state director of the Texas Farm Bureau for Region 13 in the Rio Grande Valley.

“And it doesn’t matter if it all comes on the fifth year or what, even though they’re severely lacking through these first two years of the cycle,” he said.

That 1944 treaty is just one piece of law that governs a long and complicated water sharing relationship between the United States and Mexico.

According to the International Boundary and Water Commission, over the past two years, Mexico has only delivered a third of the amount of water that farmers had been expecting. The Mexican Embassy in Washington did not respond to Marketplace’s request for comment.

The lack of water isn’t just stunting sugar cane crops in the area. It’s hurting corn and soybeans, cotton and sorghum. There are also a number of citrus growers down here, like Dale Murden.

One of Murden’s groves just south of Harlingen, Texas already took a hit during the winter freeze in 2021. Walking through the green grapefruit and oranges buds, Murden said this one is holding its own these days, but he’s worried about having enough water before the harvest at the start of next year.

Even as his own crops are suffering, he understands Mexican water commissioners are in a tough position. Things aren’t much wetter on their side of the border, and there are lots of farmers upriver who get water from the Rio Grande, too.

“You know, that’s a lot of different people to try to get together for the common good and it’s a challenge,” Murden said.

Murden also knows that climate change is only making the problem worse. 

“I’ve noticed things drying out a lot quicker lately,” he said. “I had four inches last month and four inches the month before, but things are just dry. I don’t know. It just was really drying out quick for some reason, so that concerns me a little bit.”

If the drought continues or gets even worse, Murden says he might have to sell his farmland. And that would probably mean a whole bunch of new homes and apartment buildings where this grapefruit and orange grove sits.