Deficient Dams Pose Flood Risks

The number of American dams rated as "deficient" has topped 1,000, which could spell disaster for many floodplain communities.

1 minute read

September 14, 2007, 6:00 AM PDT

By Nate Berg


"Potential disaster was averted in April in Hollis, N.H., when a dozen families were evacuated and engineers made a controlled breach of an old pond dam to keep it from failing."

"Such incidents are warning signs that many of the nation's more than 87,000 dams are in need of repair. Last month's high-profile collapse of the I-35 bridge in Minneapolis focused America's attention on bridge problems. The nation's dams are worse off."

"In 2005, the last time the American Society of Civil Engineers rated America's infrastructure, bridges received a "C" grade; dams earned a 'D.'"

"Since 1999, the number of 'high-hazard' dams rated 'deficient' has more than doubled, according to data from the Association of State Dam Safety Officials (ASDSO) in Lexington, Ky. High-hazard dams are those whose failures could cause fatalities. In 1999, the US had 546 such dams rated deficient. By last year, it had 1,333."

Thursday, September 13, 2007 in The Christian Science Monitor

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