Feds Revoked Michigan Edenville Dam License in 2018: ‘Failure … to Safely Pass Flood Flows’

The Federal Energy Regulatory Commission revoked the license for the Edenville Dam in central Michigan — which breached Tuesday — in 2018 because of concerns that the dams would not be able to withstand heavy flooding.

Both the Edenville and Sanford Dams are owned by a private company, Boyce Hydro LLC, as part of a four-dam complex. The FERC revoked the company’s license to operate the Edenville Dam in September 2018. The order says that Boyce Hydro failed to address deficiencies in the dam spillway for the 14 years in which it had the license:

Of particular concern is the project’s inability to pass the Probable Maximum Flood (PMF) [footnote omitted] due to inadequate spillway capacity. The Commission’s Dam Safety Guidelines require the project works to be designed to safely handle a flood up to the PMF either by withstanding overtopping of the loading condition during such a flood or alleviating the risk such that dam failure would no longer constitute a hazard to downstream life or property. [footnote omitted] In the alternative, the capacity of the spillway [footnote omitted] must be adequate to prevent the reservoir from rising to an elevation that would endanger the safety of the project works. [footnote omitted] Currently, spillway capacity at the Edenville Project can only pass about 50 percent of the PMF.

FERC concluded that “revoking the license will leave the community and state agencies increased authority to deal with Boyce Hydro’s noncompliance.” Oversight of the dam falls under the responsibility of the Michigan Department of Natural Resources, though local county governments also have significant responsibility for inland dams.

The town of Midland, Michigan, home to Dow Chemical Company, is expected to face flooding to depths of several feet.