Transcript for ‘Mega-drought’ covers 293,000 square miles of Southwest, experts say
about the crippling doubt across multiple states. The alarming images tonight of lake Meade at the Hoover dam. It's part of the Colorado river system. The water supply for 40 million Americans. Our chief national correspondent Matt Gutman tonight at the Hoover dam. Reporter: Tonight, the images of this mega-drought are written across the southwest's landscape. Bathtub rings around reservoirs show where the water once was. Boat Maria marinas and fields bone dry. Experts say lake mead, part of the Colorado river system that provides water to some 40 million people in seven states, is at just 37% capacity. Officials say it will dip to its lowest level ever recorded tomorrow. Over the past two decades, the water level here at lake mead has decreased by about 130 feet, that is like a 13-story building. Revealing islands that had once been completely submerged. Water from this lake makes agriculture possible in the desert southwest. Farmers throughout the region are struggling. It's an economic disaster. We don't plant crops, we don't have jobs, we don't produce food. And as we saw during the pandemic, you know, this industry is essential for everyone. Reporter: Lake mead's Hoover dam provides hydroelectric power to the region, but the dwindling water supply forcing the dam's output to be cut by nearly 25%. And at some point, officals warn, it could be forced to stop producing altogether. Nearly 300,000 miles of the southwest are in exceptional drought, an area bigger than the state of Texas. Last year was the worst fire season and this year even drier. Experts say it's being driven by climate change. Really important to stay on this and Matt, the federal government could soon be forced to take some unprecedented steps here? Reporter: Major steps, David. For the first time this summer, the federal government is set to announce a water shortage along the lower Colorado river. That triggers automatic cuts to water in Nevada and in Arizona, starting as early as next year. David? Going to affect a lot of people. Matt Gutman, thank you.
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