Minnesota Dam: “Imminent Threat”

June 25, 2024

The flows peaked yesterday … this the second largest flood of record at this Rapidan Dam.

Blue Earth County Engineer and Public Works Director, Ryan Thilges, about the partial failure of the Rapidan Dam in Minnesota.

Why It Matters: Following a flooding event, large debris in the river (think trees, telephone poles, parts of homes) has compromised a Minnesota dam, resulting in a “partial failure” when the river began flowing around it. While flash flood warnings continue for the area, no warnings for “mass evacuation” have occurred yet, though officials called it an “imminent threat” raising alarm. In a message to the public, a captain from the local sheriff’s office warned people about the dangers of driving on water-covered roadways. The most recent updates from local government officials include a list of road closures, plus a warning about ticketing pedestrians and vehicles who disregard barriers in order to get a closer look at the dam’s status.

What Is a Dam? “A dam is a structure built across a stream or river to hold water back. Dams can be used to store water, control flooding, and generate electricity.” (National Geographic) In today’s age, how do engineers contain a river flow? With concrete. But historically, it was rocks and clay.

Historic Context on the Rapidan Dam: A few years ago, the results of a feasibility study included a recommendation to either remove or repair the Rapidan Dam after flooding caused “significant damage to the dam’s structure and usability.” Reportedly, neither occurred due to the expense.

Read More:

Latest presser: Blue Earth County Public Works
“Rapidan Dam updates with Blue Earth County Sheriff’s Office” (KEYC News Now)
“Where is the Rapidan Dam and what is its history?” (CBS News)
Blue Earth County, Minnesota – Government’s Facebook page

Photo Credit: Ben Henry/KSTP-TV

by Aimee Roberts, based in Virginia