Michigan has thousands of aging and under-maintained dams that could pose localized risks.
The Michigan Department of Environmental Quality tells the Detroit Free Press that all but six of the state's 88 potential high-hazard dams are approaching 50 years old, the average engineered life span for a dam.
The American Society of Civil Engineers gave Michigan a D grade on the condition of its dams in 2009, saying more than 90 percent of the state's nearly 2,600 dams would reach or exceed their design life by 2020.
A new report card is in the works for this spring, but report card co-author Jeff Krusinga says the grade "won't be getting any better."
Krusinga says any dam collapses in Michigan wouldn't be as bad as the possible Oroville Dam collapse in
