If the Big One hits, everyone knows the drill: duck, cover, and hold.
But what about the Big Wave? As in, tsunami?
“I’d grab my purse and drop all my crap and I’d get in my Range Rover and I’d leave,” said Mala Quattman, 60, of Danville. At Alameda Beach where the estuary waves barely touch the shore.
Sia Nicole, 22, of Oakland, who was painting with her dog Simba in Lake Merritt, said she would go to the roof of her apartment building just minutes away, as it is in a safe area.
Nicole said, “I’ve seen enough movies to know that you should keep calm.” “If you’re nervous, if you don’t keep your head straight you can’t get where you want to go.”
Quattman and Nichol were recently interviewed at two Bay Area locations identified by recently released California Geological Survey maps as tsunami-prone areas.
The bad news is that tsunamis are a somewhat common occurrence, but the good news is that the scariest tsunamis—those that are 25 to 30 feet high when they enter the Golden Gate, run across bays, crash into shores and Swallows city blocks – likely only once every 1,000 years. Of course, that 1,000-year event could come at any time.
“Tsunamis happen a lot. It’s surprising. But most of the time they’re only picked up on tide gauges because they’re small,” Rick Wilson, a senior engineering geologist with the California Geological Survey, said in an interview.
But while there is only a 5% chance that the Bay Area will see a massive tsunami in the next 50 years, people still need to plan as if tomorrow the millennium could bring the event, Wilson said.
“The better information the public has, the more likely they are to save their lives and the lives of their families,” Wilson said, “and that’s what we want.”
When a large tsunami occurs, the damage can be devastating. According to the California Department of Conservation, the most devastating to reach California in modern history occurred on March 28, 1964. During that event, “multiple surges 21 feet high swept Crescent City four hours after a 9.2 magnitude earthquake in Alaska, killing 12 people and leveling most of the city’s business district.”
More than 150 tsunamis have affected the coasts of California since 1800, but only a few have had a significant impact except for one in Crescent City.
More recently, the 2011 Tohoku earthquake and tsunami waves in Japan – which killed more than 18,000 people there – caused nearly $100 million in damage and one person killed in California ports and harbors, including Santa Cruz.
The Geological Survey has been updating tsunami hazard maps from last summer for a millennium event, including maps of Bay Area counties in recent months.
“The Japanese really only planned historical events from 100 years to 500 years, and it turns out they found a 1,000-year event. For us, it was like a call to look and check and see what happened to California’s What a 1,000-year event would look like to protect your coast,” Wilson said.
The updated maps are based on “worst-case scenarios” such as a magnitude 9.3 earthquake near Alaska’s Aleutian Islands. A powerful earthquake that could trigger a mile-long chain of giant waves traveling at jet speeds toward the coast of the Golden State could arrive in about five hours.
“It may sound like a lot of time, but it will take an hour or so for the National Tsunami Warning Center to issue a warning to California and then additional time for local officials to determine if evacuation is necessary,” he said. Wilson warned. “The bottom line is, if you are near the coast and feel a strong tremor from a local earthquake or get an official notification to evacuate, move inland as soon as possible.”
Although the three-storey high waves probably lose some shape and steam as they move into the bay as they enter the Golden Gate, they can descend 12 feet above the normal waterline, covering the western regions of Oakland, Berkeley and Richmond. can submerge. As well as San Francisco’s Marina District, according to Stacey Morrison, a spokeswoman for the Department of Conservation.
Treasure Island would be covered and much of Alameda would be flooded, saving a small central part of the island.
Some places in the Gulf will be wiped out while others will be spared. All Oakland International Airport would go down but San Francisco International should survive in good shape except for a few wet runway edges.
Sections of Interstate 880, 80, and 580 can get wet through parts of San Leandro, Oakland, Emeryville, and Richmond.
The Warriors’ $1.4 billion Chase Center in San Francisco would be flooded, as would the Giants’ Oracle Park and most of the waterfront north of there.
And if Oakland A builds the $1 billion waterfront ballpark at the Port of Oakland’s Howard Terminal, it will be hit by powerful waves, too.
The tsunami is expected to become extinct as it moves south toward southern Alameda County, San Mateo County, and Santa Clara County. Wilson said that around the gulf, how high and far the inland rise reaches will affect how low the land is.
San Jose International Airport will remain dry because the waves should have shrunk to only a couple of feet by the time they reach the South Bay. The Googleplex in Mountain View and Yahoo’s headquarters in Sunnyvale should emerge in full swing. Facebook’s campuses in Menlo Park are visible on the map located just outside potentially wet areas.
But, Wilson said, “since it’s a strong moving current, even if it’s only a foot high, it will knock you down, and (the tsunami) has killed people on one foot as well,” he said.
And if that current is coming, it’s better to walk away from the danger than to walk away and get stuck in traffic when a tsunami hits, he said.
Tyler Everett, 33, of Berkeley, who was eating a shawarma wrap on the sands of Alameda Beach with his friend Jeanine Kovaler, 33, of Seattle, worries there will be chaos with word of the impending tsunami.
“I bet most of you guys would get in the car. If it were like this now, we’d be jumping in the car. I’d probably go back to Berkeley. I’ll get my cat,” he said.
Kovaler jokes that indecision can ruin him, even with hours of warning.
“Honestly, I’d die. Because I’d go back to my house and be like, ‘What do I get?’ And I will spend the next five hours packing,” she said.
Although Wilson said new massive sea walls being built in Foster City should avoid a major tsunami, a promontory at Shorebird Park where 59-year-old Prakash Das takes his dog along Beach Park Boulevard could be flooded.
But according to the state map, Das would have to walk a block west to safety, so he likes the prospect of survival.
“I’m like a math guy,” he said.