Investigations Into California’s Dam Crisis Suggest Thousands More Could Be at Risk

Officials were warned 12 years ago.

Investigations are underway to figure out what actually happened in the months and years leading up to this week’s unprecedented failure at two spillways on the Oroville Dam in California – the tallest in the United States.

While information is still be gathered, early reports have stated that three environmental groups warned federal officials way back in 2005 that something like this could happen, and what’s perhaps even more concerning is the fact that Oroville is just one of nearly 100,000 dams across the US that are in serious need of repairs.

“The last time the American Society of Civil Engineers issued its Infrastructure Report Card was in 2013, when it gave US dams a ‘D’ grade, and reported that more than 4,000 are deficient,” Jacques Leslie reports for the Los Angeles Times.

“The group will publish a new report card next month; while its contents haven’t been released, a spokesperson told me the conclusions of the 2013 report card are ‘still fairly accurate’.”

What’s perhaps most notable about the crisis is just how suddenly it occurred, and how ill-equipped officials on the scene appeared to be when it came to predicting the outcome of events.

Panicked messages from the Butte County Sheriff early on painted a vastly different picture to that of the California State Department of Water just hours later, and locals were left to wonder what was actually going on.

But how can a crack this big catch anyone by surprise?

According to Justin Pritchard and Ellen Knickmeyer at the Associated Press, inspectors with the state agency that operates and maintains the dam did not find any concerns in either 2014 or 2015.

The biggest issue appears to be how the dam managers were addressing the crack – there seems to have been little done to actually mend the spillway, with staff reportedly taking a ‘bandaid’ approach to the situation.

“We don’t have details on the repairs, but they put cement into the cracks and troweled it over,” Robert Bea, professor emeritus of civil and environmental engineering at the University of California at Berkeley, told the Associated Press.

“I call it ‘patch and pray.'”

And this is particularly worrying when you realise that the dam operators had been warned of this exact risk 12 years ago, by three environmental groups: Friends of the River, the Sierra Club, and the South Yuba Citizens League.

The Oroville Dam is now almost 50 years old, and has never undergone the kinds of upkeep it clearly required, and as you can see in the graph below, it’s just one of thousands of dams of a similar age:

“A 2016 survey by the Association of State Dam Safety Officials estimated the cost of repairing deficient dams that currently place downstream residents at risk at $22.91 billion,” the Los Angeles Times reports.

“Carrying out that task would take many decades.”

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