Crews have started emergency construction work on a portion of a central Michigan dam that collapsed last spring and contributed to flooding that destroyed homes and forced the evacuations of about 10,000 people.
Excavation work will be done below the Edenville Dam in Midland County, according to state officials.
The dam failed during a steady rain in May, draining Wixom Lake and unleashing the Tittabawassee River, which then overwhelmed the Sanford dam, about 140 miles (225 kilometers) north of Detroit.
Work also is being done inside the Tobacco River spillway in Gladwin and Midland counties to prepare it for being lowered by 21 feet (6.4 meters), officials said.
Lowering the spillway crest is expected to alleviate concerns about the stability of the remaining dam embankment, restore natural flow to the Tobacco River, reverse negative impacts on natural resources and seek to avoid another major flooding event when winter snow melts and spring rains arrive.
Crews are expected to complete the project in about 2½ months.
Michigan’s Transportation department and the Department of Environment, Great Lakes and Energy approved $2.3 million for the work. Federal funds will cover about 75% of the cost.
Dam operator Boyce Hydro Power, which has filed for bankruptcy protection, has blamed the state and residents, accusing them of insisting on high water levels.
The Edenville Dam is classified as a high hazard dam. Another collapse could result in severe downstream flooding, according to the state.
A temporary causeway bridge also will be built to replace one destroyed by floodwaters.
