20 May 2020
Edenville dam: a major dam collapse in Michigan
Posted by Dave Petley
Edenville dam: a major dam collapse in Michigan
In Midland County, Michigan, USA a dam collapse is underway, driven by heavy rainfall. CNBC has a good article about the ongoing accident, which is causing extensive flooding. Unfortunately, as I write, reports are coming in that a second dam, at Sanford in the same area, has also breached.
The Edenville Dam is located at 43.813, -84.376. MLive has excellent aerial footage of the breach, and the extensive downstream flooding:
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The town of Edenville is located about 1 km downstream of the dam:-
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At the moment the cause / mechanism of the failure is not clear. ABC12 has a report from 2018 that the licence for the dam had been withdrawn by the Federal Energy Regulatory Commission because the structure had insufficient capacity to handle the Probable Maximum Flood. The FERC ruling is available online, and states the following:
Of particular concern is the project’s inability to pass the Probable Maximum Flood (PMF) due to inadequate spillway capacity … Currently, spillway capacity at the Edenville Project can only pass about 50 percent of the PMF.
NBC25 reports that the designs for a remediation of the hazard were being prepared, with construction anticipated in the period 2021 to 2023.
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On reflection 1: Cyclone Amphan
Cyclone Amphan will make landfall in a few hours from now in NE India; this remains an extremely dangerous storm. As I have noted previously, although we categorise tropical cyclones on the basis of wind strength, most of the damage is typically caused by water. India and Bangladesh have well-established systems for evacuating people exposed to storm surge (although in the time of Corona Virus these will be tested to the maximum), but this storm is likely to cause substantial levels of inland damage from flooding and landslides.
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On reflection 2: submarine landslides in the Gulf of Mexico
New research, published in Geophysical Research Letters, has detected 85 previously unknown submarine landslides in the Gulf of Mexico. Most of these landslides were triggered by the passage of seismic waves from distant earthquakes. The study suggests higher than anticipated levels of hazard to both underwater infrastructure and coastal communities.
Thanks for the clear, fact-based post. Reading the FERC order, they revoked the hydropower license in 2018 after a long record of many years of the dam owner neglecting to follow the terms of the license. So their project allegedly planned for 2022 is quite out of time. There should be no excuses tolerated for failing to maintain a dam. The owner should have raised its rates and assessed lakeside landowners a fee commensurate with the cost of maintaining a structure to state, federal, and engineering standards. That’s the price of responsibility of owning a dam and living alongside a lake! It will be interesting to see the annual exceedance probability of the storm event which initiated this sad event and how it compares to the Probable Maximum Flood. Oh, well, people in the flood path and the rest of us will fund such a study, just like we subsidized the dam owner’s business and the property owners’ lifestyle choice and unwillingness to pay for the services which benefitted them.
Further to Mr. Bradshaw’s post. I am not sure why we do not characterize these events for what they are.
1. FERC is fickle and feckless, it has no regulatory authority aside from licensing (tax collecting) and portfolio management. It cannot punish, order repairs, cite with felony perview, penalize with civil and statutory penalties…nothing.
2. The state of Michigan, for the years since …what 1999, if not before, knew the spillway was not right sized, and allowed people to build near, on, and downstream from the reservoir in ANY year flood plain. We are clearly as a nation not capable of knowing where and when we are in a 100, 500, 1000 year flood — who has been here 100 years?.
3. Every engineering firm, consultant, and licensed professional who worked on that site knowingly, while it was under citation, or out of licensure, and did not move to shut it down, drain the lake in a controlled state or otherwise address in writing and duty what was known to be deficient, should be cited and sanctioned.
4. We need an “MSHA” for Dams…a DSHA, so that we can do what BOR, USACE, and other dam management organizations or associations cannot, with regard to all of the private and non-agency dams — effectively assess, monitor, and manage these 1,000 of at risk structures that are a NATIONAL LIABILITY. We are afraid of ourselves and need to get over it…and get to work.