An analysis repeated by the Associated Press this year tallied more than 2,200 high-hazard dams in poor or unsatisfactory condition across the U.S. — which it said is “up substantially” from a similar AP review conducted three years ago.
In 2019, AP reported on 1,688 high-hazard dams rated in poor or unsatisfactory condition, saying this data was the result of an investigation that took more than two years.
The below provides excerpts of AP’s report on this subject:
Dams in the U.S. are on average over a half-century old and often present more of a hazard than envisioned when designed because homes, businesses or highways have cropped up below them. Meanwhile, a warming atmosphere can bring stronger storms with heavier rainfall that could overwhelm aging dams. Decades of deferred maintenance worsened the problem.
Per AP, the number of high-hazard dams in poor or unsatisfactory condition has risen partly because of stricter regulation. Some state programs, infused with millions of additional dollars, have stepped up inspections, reassessed whether old dams endanger new downstream developments and worked to identify dams long ago abandoned by their owners. Some also are updating the precipitation tools used to evaluate the risks.
The $1 trillion infrastructure bill signed last year by President Joe Biden will pump about $3 billion into dam-related projects, including hundreds of millions for state dam safety programs and repairs. However, this is still just a fraction of the nearly $76 billion needed to fix the almost 89,000 dams owned by individuals, companies, community associations, state and local governments, and other entities besides the federal government, according to a report by the Association of State Dam Safety Officials.
AP released data on several states. New York has about twice the number of high-hazard dams in poor condition as it did in 2018, due to officials pushing to assess all high-hazard dams that were previously unrated. In South Carolina, the number of high-hazard dams in deficient condition rose by a third from 2018 to 2021, after lawmakers more than doubled annual funding for the state’s dam safety program. Since 2019, California regulators have downgraded four of San Diego’s water supply dams from fair to poor condition because of deterioration and concerns they could fail because of an earthquake or extraordinary rainfall.
Addressing the problems posed by old, unsafe dams can be challenging. Repairs can be costly and take years to complete. Attempts to remove dams and empty the lakes they hold back can spawn legal battles and a public outcry from those who rely on them for recreation or to sustain property values.
