In the immediate aftermath of one of the worst disasters in Michigan’s history, evidence has emerged that the Edenville Dam failure could have been avoided. Long before the catastrophic event, both regulators and the dam’s owners knew the 96-year-old structure did not meet federal or state capacity standards, which are imposed to ensure dams can withstand major flooding. In fact, state regulators were actively investigating the dam’s capacity when record rainfall overwhelmed the structure. Flood waters washed out a 900-foot section of the dam’s eastern earthen dike, releasing the waters of Wixom Lake into the Tittabawassee River. The torrential surge flowed downstream to Sanford Lake, where it overwhelmed the Sanford Dam, inundating large swaths of Midland and Saginaw counties. Over 10,000 people were evacuated before the flood waters crested.
The Federal Energy Regulatory Commission identified the dam’s susceptibility to failure as early as 1993, urging the owner to increase spillway capacity. When the dam’s current owner, Boyce Hydro Power, LLC, acquired the dam, federal regulators brought the structural failings to its attention. However, in 2018 the federal government turned regulation of the dam over to the State of Michigan. Michigan’s regulatory scheme is far less stringent than the federal laws under which the dam formerly operated.
Despite knowledge of the dam’s weaknesses, the State of Michigan actively urged Boyce Hydro to keep Wixom Lake’s water level high, since shoreline residents and those who used the lake for recreation found higher water levels more appealing. Additionally, state regulators took more drastic action to ensure higher water levels in order to preserve habitat for certain freshwater mussels. In the falls of 2019, Boyce Hydro asked state regulators if it could lower the lake level, but the state denied the request, stating that a similar drawdown in 2018 killed a number of the endangered mussels. Boyce proceeded to draw the lake level down despite the state’s refusal. In response, the state filed a lawsuit against the company in April of 2020. Boyce claims it raised the lake level this spring because of pressure from shoreline residents and state regulators.