AMERICA'S DAMS IN SERIOUS TROUBLE

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CHRISTIAN SCIENCE MONITOR - 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."

Even that rating may be generous, a Monitor analysis of dam-inspection
data shows. 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 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.

A second category of "significant-hazard" dams (so-called because they
threaten substantial property loss) saw a rise from 339 to 949 deficient
dams over the same period. In all, 2.6 percent of the nation's dams are
deficient, according to the ASDSO.

"The growth of deficient high-hazard dams in this country is a major
issue," says Brad Larossi, legislative chairman for the ASDSO, which
represents dam-safety inspectors in all states. "The trend is rising at
such a steep slope, much faster than states can do [dam] rehabilitation.
Without question the overall trends are clear."

Several factors are behind the rise. Old dams continue to deteriorate or
may fail suddenly because of inadequate spillways and trees growing on
dams. Many states don't have enough dam engineers to keep up proper
maintenance, causing the repair backlog to grow. And as more homes and
businesses are built closer to dams, the hazards increase, a phenomenon
dam-safety experts call "hazard creep."

http://www.csmonitor.com/2007/0913/p02s01-usgn.html?s=hns

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