Minnesota officials vote to tear down dam and bridge that nearly collapsed
MINNEAPOLIS — A dam in southern Minnesota and a nearby bridge that almost collapsed The state of emergency declared last month after a period of heavy rains will be lifted, officials said Tuesday.
The Blue Earth County Board of Commissioners voted to remove the Rapidan Dam near the city of Mankato, about 80 miles (130 kilometers) south of Minneapolis, and replace the County Road 9 Bridge, both of which were at risk of crumbling. Officials began what will likely be a years-long rebuilding process as the structural integrity of the dam and bridge remain uncertain.
The Blue Earth River’s water level rose dramatically in late June and early July after heavy rain ravaged the Midwest for days. Although the structures eventually held, floodwaters forged a new riverbed around the dam and cut deep into a steep riverbank, toppling utility poles, destroying a substation, swallowing a home and removal of a beloved store.
With the specter of a future collapse still on the minds of a wary local community, officials say they must act in the name of public safety. But they are concerned about the impact of the bridge closure on local farmers, one of the main economic engines of the countryside.
“We know this is a rural community and they use (the bridge) to go from farm to market, and we know the fall harvest is coming up and it’s going to be inconvenient,” said Jessica Anderson, a spokesperson for Blue Earth County. “But safety has been our priority from day one. And we can’t afford to compromise that.”
According to Vance Stuehrenberg, a Blue Earth County commissioner, farmers may have to walk more than 45 minutes across the bridge to reach their fields.
River water washed away large amounts of sediment, causing instability in the bridge’s support pillars, which are built on sandstone bedrock. The timeline for rebuilding is unclear, but Anderson said it would be a matter of “years, not months.”
It was also unclear Tuesday how much the rebuilding would cost. Studies conducted by the county in 2021 showed that repairing the dam would cost $15 million and removing it would cost $82 million, but Anderson said environmental conditions have changed since then.
The next step is securing funding to pay for the repairs, which could come from a combination of state and federal sources. The county is working to develop a plan with federal agencies, including the Federal Emergency Management Agency and the Federal Energy Regulatory Commission, Anderson said.
A federal disaster declaration has been approved for Blue Earth County, and local officials said the extra funds will be crucial for rebuilding. But those projects could be complicated by a sensitive landscape where emergency aid can sometimes exacerbate the deterioration, officials have also warned.
Stuehrenberg also worries about the impact the closure could have on recreation near the dam, a popular area for biking. Minnesota Gov. and Democratic vice presidential candidate Tim Walz, who visited the dam in July, is among those who used to ride his bike along a nearby trail.
The Rapidan Dam is over a century old, having been completed in 1910. Although it was built to generate electricity, it has been damaged by several floods in recent decades. The dam no longer produces electricity, as previous floods wiped out that small source of income.
There are approximately 90,000 major dams in the United States. According to data from the U.S. Army Corps of Engineers, at least 4,000 are in poor or unsatisfactory condition and could cause human loss of life and environmental damage if they fail. They need inspections, upgrades and even emergency repairs.