How extreme weather can threaten California’s dams

You may have heard that California’s climate change is exacerbating what’s sometimes called “weather whiplash”: dry spells last longer, punctuated by storms that get bigger and more intense.

In other words, our extremes are getting more and more extreme.

For a recent issue of The New York Times Magazine, Christopher Cox addressed the question of how extreme weather could threaten California’s dams, an essential part 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. The failure of that dam would be catastrophic; in a particularly alarming scenario, it would drive a wave more than 180 feet high into the valley and engulf 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 so regularly threatened by Mother Nature, the risk of flooding from dam failure doesn’t get much attention. And that’s despite the fact that just six years ago, as Christopher reported, the Oroville Dam nearly failed.

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

California’s dams are not prepared for extreme weather, experts told Christopher.

In 1862, the worst flood in the state’s recorded history drowned the Central Valley and reportedly destroyed a quarter of all buildings in the state. But most of the flood data used to design our dams comes from the past century, which experts say was an unusually calm period in California weather.

Now, however, storms are getting more intense as the atmosphere warms and the amount of water vapor it can carry increases. “All this infrastructure,” says Daniel Swain, a climate scientist at UCLA, “is designed for a climate that no longer exists.”

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

“While an earthquake seems more like an act of God,” Cox told him, “a flood points to man’s shortcomings.”

A truly comprehensive approach to dam safety often slips through the cracks, as meteorologists, hydrologists, engineers and climatologists focus only on their parts of the equation and not the overall picture. That seems to make officials and experts very vocal about the problem.

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

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Where we travel

Today’s tip comes from Phoenix, Canada, who is visiting the Manzanar National Historic Siteone of 10 camps where the US government imprisoned Japanese Americans in the 1940s:

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

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