The Lake Lure Dam in western North Carolina flooded Friday after Hurricane Helene inundated the area, forcing evacuations and officials warning that the dam could fail.

Warnings of a second possible dam failure in the state – Walters Dam, less than 100 miles from Lake Lure – also caused concern in nearby Newport, Tennessee, as residents were urged to evacuate.

The Lake Lure Dam, located about 25 miles east of Asheville, is still at risk of failure and could flood downstream communities if it does. According to the North Carolina Department of Environmental Quality, officials in South Carolina have been warned that an outage could even impact cities there.

“RESIDENTS BELOW LAKE LURE DAM MUST IMMEDIATELY evacuate to higher ground!!” the Rutherford County Emergency Management Department wrote in a Facebook post around 11 a.m. ET on Friday. “DAM FAILURE IMPANT!!”

As of 1:30 p.m., water overflowed the dam, the disaster management agency said.

“Structural supports have been compromised, but the dam is currently holding,” the agency wrote on Facebook. “Emergency personnel are working with civil engineers and going door-to-door to ensure all citizens have been evacuated.”

The 124-foot-tall dam, located on the Broad River about 25 miles from Asheville, is operated by the city of Lake Lure, according to the National Inventory of Dams. Its maximum storage is 44,914 acre-feet, which is approximately the same amount of water as 22,500 Olympic-sized swimming pools.

Lake Lure City Manager Olivia Stewman said water was flowing around the dam on one side. She added that emergency response was being complicated by blocked roads and fallen trees across the area.

“Our dam engineer is on his way here. As soon as he can get here, he will conduct a site survey to determine the condition,” Stewman said. “Right now, our first responders and public safety departments are working to do the best they can.”

The North Carolina Department of Environmental Quality also said on its website Friday morning that the 480-foot-long dam was eroding on one side. An update released earlier in the day said dam operators were out of power but could operate the floodgates manually.

The southern Appalachians have been under flooding for several days after a precursor storm brought rainfall in some areas that is expected only once every 1,000 years. Then the remnants of Hurricane Helene hit overnight and into Friday morning.

Jared Klein, a meteorologist with the National Weather Service, said the area near Lake Lure has been hit by extreme rainfall over the past three days.

“In the lake area, 20 to 40 centimeters of rain falls,” said Klein.

Lake Lure is considered a “high” risk dam according to the National Inventory of Dams — a classification that means failure or misoperation is likely to result in loss of life. According to the inventory, the dam was in “good” condition during an inspection in March 2023.

The city of Lake Lure has been trying to replace the aging dam. As of June 2023, the company had received at least four grants from the Federal Emergency Management Agency to help rehabilitate or replace high-risk dams. Additionally, the company received $16.5 million from the state of North Carolina in 2022 for the project.

According to the city's website, water levels in the lake were lowered earlier this year to replace critical infrastructure. Over the summer, contractors worked on a project to install a reservoir drain, called an “emergency preparedness facility,” that would allow the lake to be lowered before a storm.

Meanwhile, confusion reigned in Newport, Tennessee, on Friday after local officials announced that the Walters Dam – also known as Waterville Dam – had “suffered a catastrophic failure.”

However, Kristin Coulter, communications director for the Tennessee Emergency Management Agency, said later in the day that it was a false alarm but that the city of Newport remained at risk.

“It’s not failure,” Coulter said. “Officials have asked residents to evacuate.”

Stream data from the United States Geological Survey showed that the Pigeon River downstream of the dam was experiencing severe flooding.

Valerie Patterson, a spokeswoman for Duke Energy, said the dam and its flood gates were operating “as expected” and that the company “has opened all gates at Waterville Dam and continues to transfer water through the dam.”

The false statements about the dam's failure appeared to come from Cocke County Mayor Rob Mathis, who later declared a state of emergency for the county, according to a Facebook post. The Tennessee Emergency Management Agency shared Mathis' warning.

Overall, America's dams – more than 92,000 in all – are aging and many are in need of costly restoration. Few dams were designed for today's climate, with a warmer atmosphere that can absorb and release more intense rain. More people have now moved to the floodplains below these dams.

In a report last year, the Association of State Dam Safety Officials estimated it would cost $157.5 billion to bring non-state dams in the U.S. up to code.

According to data from the Association of State Dam Safety Officials analyzed by NBC News this summer, 283 dams in the U.S. experienced failures between 2013 and 2023. Most dam breaches ultimately do not cause public safety issues, but in 2019, a dam breach in Nebraska left a man drowned and his home washed away.