How Extreme Weather Could Threaten California’s Dams

Perhaps you’ve heard that climate change in California is exacerbating what’s sometimes called “weather whiplash”: Dry periods are stretching longer, interrupted by storms that are growing bigger and more furious.

In other words, our extremes are becoming more extreme.

For a recent issue of The New York Times Magazine, Christopher Cox tackled the question of how extreme weather could threaten California’s dams, an essential piece of the state’s complicated water storage and distribution system.

California is home to the tallest dam in America, located 60 miles north of Sacramento in Oroville. A failure of that dam would be catastrophic; in one particularly alarming scenario, it would send a wave more than 185 feet tall sweeping into the valley below, inundating several towns. When the St. Francis Dam in northern Los Angeles County failed in 1928, the disaster was one of the deadliest in state history.

But in a state threatened so regularly by Mother Nature, the risk of flooding from a dam failure doesn’t tend to get much attention. And that’s despite the fact that just six years ago, as Christopher reported, the Oroville Dam nearly failed.

“Fires happen more frequently, and drought years are more common than wet ones,” he told me. “But the biggest disasters in the state’s history have been floods.”

California’s dams are unprepared for extreme weather, experts told Christopher.

In 1862, the worst flood in the state’s recorded history drowned the Central Valley and, by one account, destroyed one-quarter of all the buildings in the state. But most of the flood data used to design our dams comes from the past century, which experts say has been an unusually placid period in California weather.

Now, though, storms are getting more furious as the atmosphere warms and the amount of water vapor it can carry increases. “All of this infrastructure,” said Daniel Swain, a climate scientist at U.C.L.A., “is designed for a climate that no longer exists.”

Some scientists have been urging the state to prepare for a storm on the scale of the one in 1862, but there’s been little progress. Dale Cox, a former project manager at the United States Geological Survey, told Christopher that he thought part of the reason was that floods don’t captivate the public in the same way as earthquakes, which are more sudden and dramatic.

“Whereas an earthquake is more like an act of God,” Cox told him, “flooding points out the flaws of man.”

A truly comprehensive approach to dam safety tends to slip through the cracks, as meteorologists, hydrologists, engineers and climatologists focus only on their pieces of the equation and not the overall picture. That seems to make officials and experts particularly tight-lipped about the problem.

“Dam safety,” Christopher wrote, “is an orphaned problem.”

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Where we’re traveling

Today’s tip comes from Phoenix Kanada, who recommends visiting the Manzanar National Historic Site, one of 10 camps where the U.S. government incarcerated Japanese Americans in the 1940s:

“It is truly a balance of beauty and darkness as it commemorates the thousands of Japanese Americans that were sent here during WWII. The site serves as an important reminder of this country’s past and how we as a people can be more understanding toward one another. Plus, the landscapes in the Owens Valley (where this site is) are truly remarkable.”

Tell us about your favorite places to visit in California. Email your suggestions to CAtoday@nytimes.com. We’ll be sharing more in upcoming editions of the newsletter.