Fergus Falls was calling me over the weekend, and that call finally proved irresistible. I’d heard through the grapevine about the ruins of an old dam along the Otter Tail River that collapsed back in the day. Well, I quit listening after the word “ruins” because I already knew I wanted to see “Broken Down Dam Park.”
Folks in that area built what’s called a hydroelectric gravity dam on the river in 1907. The dam was built out of concrete and powered a plant called the Fergus Falls City Light Station. The station provided power to city residents for just a year before disaster struck.
The large concrete dam suddenly collapsed in 1909, and you did not want to be downriver from the massive wall of water that suddenly rushed down the Otter Tail River. Can you image the roar of all that water moving at once?
The dam broke at 4:20 in the morning on September 24, 1909, and the power of all that water releasing at once broke not one, not two, not three, but FOUR other dams downriver. Atlas Obscura says there were reports that the water was so powerful, it picked up a ten-ton generator and threw it into the river. Thankfully, no one died as a result of what was a catastrophe of immense size.
A wiki article (which I was able to validate in several other web pages) says that engineers made a crucial mistake when they constructed the dam. They didn’t conduct a proper site evaluation and wound up building on top of a spring. While I don’t pretend to understand how a spring can flow separately from a river while occupying the same space, it only took a year for the water pressure to build up along the foundations. The rupture washed out the concrete foundation and undermined the structural integrity of the dam, which then collapsed.
The dam broke in the center, and the rushing water first took out the Kirk Dam, which powered the city’s waterworks. The water then took out the Mount Faith Avenue Bridge before sweeping away the Red River Mill Dam and Woolen Mill Dam. Damage to the two mills totaled $15,000, with the damage in today’s economy equivalent to $432,000 in 2020.
Conspiracy theory alert: The Dayton Hollow Dam, five miles southwest of where the dam broke, was saved from destruction. The dam’s owner, Vernon Wright, had enough warning to hustle down there in time to get the floodgates open. The conspiracy? He also was president of the Otter Tail Power Company.
The city of Fergus Falls then hired Otter Tail Power to build transmission lines into town. That helped spawn a local rumor, fueled by the newspaper, that Wright deliberately destroyed the city’s dam by secretly distributing quicksilver from a rowboat to undermine it.
Broken Down Dam Park was established in 1949, an 11-acre parcel of land. When the water level on the Otter Tail River is high, the flow can go fast enough between the blocks of the structure to create Class 3 rapids.
Here is the link to my complete photo album from Broken Dam.
https://www.facebook.com/media/set/?vanity=chad.smith.75685&set=a.4467526469974421