I saw a short video yesterday that appeared to show water had bored through the earthen portion of the Edenville dam. And once the earth starts eroding, it will go quickly.
Seems that the problem might have been that there was a growing, and undetected issue with the stability of the soil that made up the earthen portion of the dam.
I don’t know if the second dam downstream, was overtopped or not. Cletus lives around there, and has good information, I’m sure. If he’s not floating downstream right now. Seriously, when the top dam failed, the entire lake had to empty downstream, and the lower dam may not have been capable of holding that amount of water. With luck, it’s not damaged.
correct-a-mundo!
If you look up-thread, you will see a photo of the Sanford dam which held, structurally.
to the south, though, and right at my favorite fishing spot, you will see that the “levee” was overtopped and quickly eroded.
This could not have been stopped nor predicted as hydro-dams aren’t planned for domino failure like this. The sheer amount of water that flowed into Wixom lake above the Edenville dam was more than any 100-year rain event.
Heavy rains are typically handled by releases and allowing the impoundments to increase it’s bounds temporarily (cottages get flooded). But that intends a slow input of water over time.
My rain guage (electronic) showed 7.3 inches of rain in the 24-hour period from 3AM TUE to 3AM WED. Water in my backyard came within a foot of my foundation sills. Dicey.