52 years after an an 8.8 magnitude earthquake in Alaska caused a fatal Northern California tsunami, experts warn that the seawall at Ocean Beach would do little to protect San Francisco if a deadly wave were to strike the city's shores.
It was March 28, 1964, and the Alaska quake sent a wall of water toward the small coastal town of Crescent City. Eleven people were killed and the city's business district was destroyed. "Accounts from the time reported that fuel tanks erupted in flames while cars and trucks washed down city streets, pilling up against buildings," the LA Times reported. Check it out:
The anniversary of the disaster, as well as the March 11, 2011 anniversary of the Tohoku earthquake in Japan (the tsunami from which also caused significant damage in Crescent City, due to its unique geographic location), prompted Governor Jerry Brown to declare March 20-26 Tsunami Preparedness Week, and to "urge all Californians to continue their vigilance and increase their efforts to make our families, communities, state and nation better prepared for disasters including tsunamis." (You can read his full proclamation here.) (Also, did you know that CA has an "Earthquake, Tsunami and Volcano Program"? That department is basically every straight-to-streaming movie Netflix keeps saying I might like.)
According to the Associated Press, as part of this week's preparedness activities, between 11 a.m. and noon today the The National Weather Service and California Office of Emergency Services will use NOAA's All-Hazards Radio, the Emergency Alert System, and TV and radio stations to transmit tsunami warning codes in Del Norte, Humboldt and Mendocino counties. Other NorCal costal cities will get "a 'required monthly test' message via NOAA radio and TV and radio stations," they report.
Warnings and alerts are great — in 1964 Crescent City, some residents say they didn't even get that! But are there other things that will protect San Francisco from a tsunami, should one strike? Not on the Ocean Beach side, Jerry Shuman, Chief of Facilities for the Golden Gate National Recreation Area, tells CBS 5.
Shuman's crews are the ones currently repairing the century-old, crumbling O’Shaughnessy Seawall at Ocean Beach, a project that began in March of last year, the Chron reported at the time. The seawall was initially intended to protect the Great Highway and Golden Gate Park "from sand and waves," the Chron reported, as "they used to wash much farther inland." But Shuman's not so sure that it's up to the tsunami task.
“One of the things that the sea wall has done for us, it holds the sand back from blowing onto the parking lot, and onto the Great Highway, making it safer for the vehicle traffic,” Shuman told CBS 5.
“As far as a small tsunami, I’m sure that may help holding back some of the ocean, but I’m not sure what it would do in a large scale."
Which is probably no big deal, since experts say that the type of faults we have in the Bay Area aren't conductive to tsunamis — according to KQED, the 1906 quake only got us an additional four inches (oh, grow up).
But in the spirit of Brown's proclamation, here's a simulation of how it would likely look if a big tsunami did indeed hit the Bay Area:
Also, here's SF's Tsunami Inundation Map (looks like I'll be heading to Jay's if the tsunami hits). And for you SF tsunami superfans, here's our full, 44-page Tsunami Emergency Response plan. Happy Tsunami Awareness Week, everyone!