<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/MojaveDamCOE%20copy.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/MojaveDamCOE%20copy.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/MojaveDamCOE%20copy.jpg?v=ap&w=980&h=551 800w" > The Mojave River Dam is pictured in this undated photo. (U.S. Army Corps of Engineers Los Angeles District )

At a Glance The dam was built in 1971.

A recent risk assessment showed that it could fail in an extreme weather event.

The chances of such an event are low, Corps says. California's Mojave River Dam is at high risk for failure if it were to face extreme flooding, the U.S. Army Corps of Engineers said Friday.

The Corps upgraded the dam's status from "low to high urgency of action," according to a press release.

The 200-foot high dam met design standards when it was built in 1971, but the Corps said a recent risk assessment showed that water from an extreme storm or flooding event could exceed those standards and overtop the dam.

“The dam has never experienced spillway flow or a flood event that has loaded the dam significantly,” Col. Aaron Barta, commander of the Corps’ Los Angeles District, said. “This is a storm that is unlikely to occur, but it is nonetheless a real possibility and one we must be prepared for."

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A failure of the dam could potentially flood the communities of Hesperia, Apple Valley, Victorville and Barstow, located adjacent to the river. The Corps said flood waters in such an incident could also reach Baker, more than 140 miles downstream from the dam.

The Corps of Engineers has been assessing all its dams nationwide, many of them built decades ago, since Hurricane Katrina flooded New Orleans in 2005.

In May, the agency increased the risk for the Prado Dam , also located to California. In a high-profile incident for dams in the state, parts of the Oroville Dam crumbled away during heavy rains in 2017 and forced some 200,000 people to evacuate. Repairs cost $81 million.

The chances of a storm that could overtop the Mojave River Dam are only about 1-in-10,000, Luciano Vera, spokesman for the Los Angeles district of the Army Corps of Engineers, told the Associated Press.

But scientists predict that extreme weather will become more frequent as climate change affects weather patterns.

"All it takes is one event ... one Katrina, one Hurricane Harvey," Vera said. "These storms are happening more and more, so this is our way of looking toward the future."

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