Rapidan Dam’s concerning history revealed as officials keep an eye on structural integrity

Rapidan Dam’s concerning history

As federal regulators and the Army Corp of Engineers keep a close eye on the Rapidan Dam’s structural integrity, 5 EYEWITNESS NEWS is learning about concerns at the dam that dates back years.

During a news conference Tuesday morning, county officials said the latest inspection just last month found the dam to be in satisfactory condition. But 5 INVESTIGATES found a long history of problems, concern and previous unrepaired damage.

The century-old Rapidan Dam caused trouble for Blue Earth County long before it partially collapsed earlier this week.

“There were severe damages to the dam that happened, that.. that we’ve been studying, been trying to determine the path of action for the county because of the tremendous financial investment to the county,” said Blue Earth County engineer Ryan Thilges.

Since the damage in 2019, county officials say they’ve been debating removing the dam or fixing it… and records show there is a lot to fix.

A letter from the Department of Natural Resources last April said the dam was in “poor condition” after the 2019 floods.

Last month, federal regulators called it “satisfactory” but listed a host of issues including “large cracking,” “severe concrete deterioration” and regulators said no one should be allowed in certain areas because “There are signs… of falling concrete.”

“We’re still concerned about, and again, that’s why we’ve got Army Corp of Engineers out here and we’ve got Federal Energy Regulatory Commission folks coming out as well,” added Thilges. “They’re still concerned because the dam was constructed on highly erodible sandstone bedrock when it was built in the early 1900s.”

5 EYEWITNESS NEWS reached back out to Blue Earth County to try to get clarity on how this dam went from “Poor condition” and improved to “Satisfactory condition” just last month.

They did not answer that question and referred us to other federal and state agencies.