Federal engineers have discovered that a dam protecting some of the communities in the Mojave desert, such as Victorville, Hesperia, Apple Valley and Barstow, fall short of national safety standards and could erode and collapse in an extreme flood.
Officials for the U.S. Army Corps of Engineers (USACE) raised the risk factor for the Mojave River Dam from “low” to “high urgency action” due to performance concerns. The dam, which is 48 years old, shows signs of severe stress, according to the Los Angeles Times.
“This dam was built in 1971, when climate change was still an unknown phenomenon,” said Gary Lee, chief safety engineer for the Army Corps’ Los Angeles District to the Los Angeles Times. “Climate change creates more uncertainty, which, going forward, will be taken into account.”
Dam failure could impact 16,000 people and flood $1.5 billion in property, reported the Los Angeles Times. The USACE is evaluating risk-reduction measures and anticipates some of those measures will be in place prior to this year’s winter rains.
A possible solution would be to harden the dam to prevent water flowing over the top from eroding it. Another approach would be to raise the dam by at least 3 ft. There are no cost estimates attached to these plans yet, however.
Researchers allege that the state could be hit more frequently by storms due to global warming, according to the Los Angeles Times. This will challenge the state’s ability to control flooding, as well as the storage and transportation of water.
The USACE also discovered that the 60-year-old Whittier Narrows Dam and the Prado Dam are structurally unsafe, according to the Los Angeles Times.
“The risks of catastrophic flooding are not as rare as they once were,” said Daniel Swain, a UCLA climate scientist, “and they will be less rare in the future.”
