In a social media post earlier this year, President Trump threatened tariffs and sanctions against Mexico,

claiming the country violated a 1944 treaty and is stealing water from Texas farmers.

It's part of a long-running dispute over shared water in the Rio Grande River.

A dispute that scientists say is made worse by higher temperatures, extreme weather, and a greater

demand for water. Stephanie Sye reports from Texas for our series on the impact of climate change,

tipping point. From Texas State Highway 107 in Santa Rosa, the Rio Grande Valley Sugar Mill

strikes an imposing figure. We're in the sugar warehouse.

Sugar would fill this entire warehouse as it's being processed.

But it sat empty since the mill closed its doors last year.

We started disassembly pretty much almost immediately.

Tudor Yulhorn is a former sugar cane grower and the mill's last chairman of the board.

I don't come out here like I used to with pride that I'm a sugar grower.

I come out here and it's sad to see that this whole industry is gone now.

Symbolically, it is a reflection of nobody cares about us in the Rio Grande Valley.

The closure of Texas's last sugar mill, which once employed 500 people and processed about 160,000 tons of

raw sugar annually, coincided with years of increasing water scarcity in the region.

The Rio Grande Valley is one of the few places in the U.S. where sugar cane will grow,

but it takes a lot of water.

Farmers are plowing out cane because no one has any irrigation water.

We just got completely choked off by Mexico's failure to deliver the water.

That water is owed to farmers here in the Rio Grande Valley as part of a more than 80-year-old

treaty that requires Mexico to share some of the water that winds through its land.

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