Do Two Failed Dams Foretell a Dire Future?

a legal complaintagainst the State of California for negligence in maintaining the dam.

The majority of the 90,000+ dams in the U.S. are older their nominal design life, which would not be a big issue if they were well maintained. Their state of maintenance is a concern, and this is the silent hazard that needs to be addressed. The National Inventory of Dams has approximately 25,000 dams in the U.S. that are listed as high (>10,000) or significant hazard! This is a national concern — every state has such dams, and people and critical infrastructure below them in harm’s way.

Flooding from dam failure can be much more catastrophic than what may be expected from an extreme rainfall event. The Midland, MI dam exposed one aspect of this concern. The Michigan dam failures are an example of cascading dam failure — the failure of the “unsatisfactory” Edenville dam led to the failure of the downstream Sanford dam that was rated to be in fair condition. The Buffalo Creek, West Virginia dam failures in 1972 provide another example when three dams failed in sequence failed, mobilizing a large amount of coal mining waste, rendering 4,000 of 5,000 people downstream homeless with accompanying loss of life.

The Columbia Water Center’s recent report (see summary) highlights that much critical infrastructure (dams, electricity generating plants, highways, bridges, water treatment and wastewater treatment plants) lies below dams and would be incapacitated in the event of dam failure, leading to significant and potentially chronic economic impacts. There continues to be no comprehensive evaluation of these risks or a prioritized list of dams for remedial action. Does it make sense to keep doing presidential disaster declarations each time a dam fails, or is it better to prioritize which ones to fix or remove before disaster strikes? Our report provides and exemplifies an approach that could be used to do this “rapidly,” but has not yet been applied across the U.S. due to financial and time constraints.

Michigan, the location of the most recent dam failure, is in the Great Lakes region. There is a profusion of high hazard dams older than 60 years (nominal design life is 50 years) in counties with high population (which are also likely to have thermo-electric power plants, waste facilities and drinking water intakes located on rivers). Governor Whitmer of Michigan characterized the Midland dam failure as a 500-year event, or something that would have a 1/500 chance