USA: Another looming climate disaster: Dam collapses
By Dan Vergano
In June, an analysis led by UCLA researchers concluded the Oroville Dam spillway overflow was worsened by climate change. The results of the new Geophysical Research Letters study suggest that there are at least six other major dams in California that have an even higher potential flood risk than the Oroville Dam did, study author Amir AghaKouchak of the University of California, Irvine, told BuzzFeed News. “The Oroville Dam shows what the chances of these failures look like, and might become the new normal.”
“In a warmer world, we expect more precipitation, which influences flooding,” AghaKouchak said. “We tried to look into the future to ask about the probability of that affecting dams.”
California’s New Don Pedro, Shasta, Lewiston, and Trinity Dams face the highest risk of flooding in this century, according to the new report, which combined the results of 10 climate models assuming “business as usual” for the global climate — the roughly 7 degree Fahrenheit rise path that the world is now on — with a hydrological model of 13 major dams and rivers in California. The study also analyzed a less severe future where humanity decides to lower its greenhouse gas emissions.
AghaKouchak, the study author, stressed that they broadly defined failure in the study not only as a catastrophic collapse, but also less severe problems, such as overtopping of dams or damage to foundations and spillways that exceed the limits of their design. Estimating the risk of catastrophic collapses would require a structural engineering analysis of each dam, which was not part of his study.