Much of America's ageing dam infrastructure is in urgent need of replacement or upgrade.
Civil engineers in the United States warn that the poor condition of the nation’s ageing dams poses an increasing hazard to communities and physical assets located within their immediate downstream vicinities.
Lori Spragens, executive director of the Association of State Dam Safety Officials (ASDSO), said billions of dollars in spending is required in order to remedy the problem of the country’s hazardous dams.
According to Spragens, the cost of upgrading the country’s high-hazard dams alone – defined as those whose failure has the potential to lead to loss of human life – could run as high as $18 billion. The bill for providing upgrades to all dams in country which require them would be a staggering $53.69 billion.
ASDSO estimates that during the eight-year period from January 1, 2005 to June 30, 2013 the US suffered from 173 failures, as well as a further 587 incidents which “would likely have resulted in dam failure” without timely intervention.
The failures include those of the Big Bay Lake Dam in Mississippi in 2004, which left approximately 100 homes either damaged or destroyed, and the Ka Loko Reservoir Dam in Hawaii in 2006, which resulted in the deaths of seven people as well as the destruction of state highways assets, houses and farms.
A study conducted in 2012 by the Center for American Progress found that in addition to causing an average of 94 deaths per annum, the shoddy state of US water infrastructure was costing the country approximately $7.2 billion in damages each year.
The study, entitled Ensuring Public Safety by Investing in Our Nation’s Critical Dams and Levees, found that over 28,000 dams – equivalent to a third of the US total – were more than 50 years old, which is generally deemed to be the threshold of sound usage for such infrastructure. A further 14,000 dams were also categorised by the centre as “high-hazard.”
States listed by the centre as having the the greatest number of “high-hazard dams in need of repair” included Georgia, Pennsylvania, Colorado, Ohio, North Carolina, Indiana, Mississippi, Massachusetts, New Mexico and New Jersey.
The problem of decrepit dams is just part of the broader dilemma of ageing and dilapidated US infrastructure, which was given an abysmal D grade by the American Society of Civil Engineers (ASCE) in its 2013 report card.
“The nation’s dams are ageing and the number of high-hazard dams is on the rise,” said the ASCE in its annual assessment.
The ASCE noted that as a result of population expansion and the growth of formerly rural communities, the threat to life and property posed by high hazard dams was becoming increasingly acute.
“Many of these dams were built as low-hazard dams protecting undeveloped agricultural land,” the organisation said. “However, with an increasing population and greater development below dams, the overall number of high-hazard dams continues to increase.”