The Lake Murray dam and earthquakes. What South Carolina residents should know.

A powerful earthquake in South Carolina’s Midlands could threaten the Lake Murray dam, which holds back nearly 650 billion gallons of water. Experts say a breach is unlikely, but emergency officials have planned for the worst. FULL STORY: Could an earthquake break the Lake Murray dam? It’s unlikely, but not impossible

Here are key takeaways:

• A breach of the two 213-foot tall dams at the Dreher Shoals Dam facility would send floodwater south of I-20 into the Congaree Swamp, covering a 210-square-mile area as far as 35 miles away within half a day. More than 150,000 people would be affected, according to Kim Stenson, director of the South Carolina Emergency Management Division.

• After federal officials concluded the original dam could not survive the area’s potentially strongest earthquake, a backup dam capable of withstanding a 7.3-magnitude quake was completed in 2005.

• Earthquakes have struck the Columbia area, typically between Elgin and Lugoff, with the largest reaching magnitude 3.5. Tom Pratt, a U.S. Geological Survey research geologist, said significant damage only happens after a 6-magnitude earthquake.

• Fault lines run under Lake Murray, but none have any history of activity. “We have no idea whether it’s going to lead to something bigger or not, it’s unlikely,” Pratt said.

The summary points above were compiled with the help of AI tools and edited by journalists. The full story in the link at top was reported, written and edited entirely by journalists.

This story was originally published February 26, 2026 at 1:05 PM.