California Tsunami Risk Creates Uncertainty for Residents
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On 12/5/24, the California tsunami risk got real when a rare tsunami warning – complete with blaring sirens and evacuation orders – was issued for parts of the state, as well as parts of southern Oregon. The reason for the alarm was a magnitude 7 earthquake approximately 55 miles off the coast.
The warning was soon canceled, but it provided a stark reminder that parts of the U.S. West Coast are vulnerable to these types of devastating natural disasters.
History of California Tsunami Activity
Historically, the risk of a tsunami hitting the U.S. West Coast has been extremely low. That said, there have been at least 6 damage-causing tsunamis that hit California in the past 80 years or so.
The most recent incident was in Jan. 2022, when an underwater volcano eruption in a remote area of the South Pacific created coastal flooding and caused $6 million worth of damage in Santa Cruz. Prior to that, we need to go back to 2011, when a tsunami from the earthquake in Japan killed one person and caused over $100 million in damage along the coastal parts of California.
Going back even further, the 1964 Alaskan earthquake created a tsunami that leveled Crescent City, killing 11 residents and damaging over 260 homes and businesses. There are also records of tsunamis wreaking havoc on the state in 1960, 1946, 1912, and even 1700!
The 1700 disaster in particular was a doozy. Scientists estimate that a similar event happening today would cause over $70 billion in damage, including the loss of over 100 bridges and the entire power grid along the coast, and would likely kill at least 10,000 people.
So, yes, while rare, tsunamis can and do occur. What makes these disasters trickier is that, unlike a hurricane or winter storm, they are difficult to predict and typically do not provide much advance warning. The good news is that the California Geological Survey maintains tsunami hazard maps. In addition, the National Weather Service operates two tsunami warning centers.
There’s no doubt, a California tsunami will occur at some point, it’s just a matter of when, which is yet another reason that utilities and other entities must focus on a philosophy of best-in-class emergency preparedness.
