A major earthquake hasn’t struck any of California’s biggest cities in more than three decades, but experts and officials say the so-called “Big One” is a matter of when, not if.
And the risk is far from isolated, even in a state this large.
“It shouldn’t come as a surprise that 70% of Californians live within 30 miles of an active fault,” California State Geologist Jeremy Lancaster said during a recent webinar. “We have seven active volcanoes; we have landslides; we have tsunamis; we have thousands of miles of active faults.”
But what should you do when the earth eventually starts to rumble? That’s where Thursday’s annual ShakeOut earthquake drill comes in.
Southern California will anchor its ShakeOut drill at the Los Angeles Emergency Operations Center in downtown; the San Francisco Bay Area’s will be held in front of Oakland City Hall.
Here’s what you need to know about the drill, and how best to prepare for a seismic disaster:
Drop, cover and hold on at 10:16 a.m. Thursday
This might be common sense to Californians who grew up here and remember drills in school, but maybe not so much for those who moved here from out of state. During an earthquake, the best thing you can do is to drop, cover and hold on when you feel shaking or receive an early warning alert.
“Drop down to the ground. Take cover underneath a sturdy object like a table. And hold on until all the shaking has stopped,” Wendy Bohon, branch chief of seismic hazards and earthquake engineering at the California Geological Survey, said in a recent social media video.
Isn’t it safer to just run outside?
Some people might instinctually want to run outside when the shaking starts. But there are reasons why that’s not the preferred response in California.
One of the most dangerous places to be in an earthquake is just outside a building, where you could be hit by falling glass or bricks. Brick buildings in particular tend to fall outward, so running out of one during an earthquake could be particularly risky, structural engineers say.
During the 1989 magnitude-6.9 Loma Prieta and 1994 magnitude-6.7 Northridge earthquakes — California’s last two major seismic events that struck heavily populated areas — about 50% of the injuries reported were caused by things falling on people, Lancaster said.
Dropping to the ground under something like a table and staying stationary helps protect you from falling objects. Studies from the Loma Prieta and Northridge quakes “revealed that you’re twice as likely to be injured in an earthquake if you’re inside and you’re moving around,” according to Sara McBride, the executive director of the California Seismic Safety Commission.
“Most injuries that were recorded and sustained and treated for were for movement-based injury, because people were moving around trying to do things,” McBride said during the webinar.
Studies in other nations that have a similar building stock to California, like New Zealand, confirm that “drop, cover and hold on” is generally “the best protective action for most, but not all, situations,” McBride said.
Studies suggest that the reasons why people might not follow that mantra is they could be embarrassed to do so, or because they’re caring for children and want to help them first.
But there are a number of examples where running isn’t the best option. During the Northridge quake, a mom in Rancho Cucamonga died after she raced to check on her child and struck her head on the crib.
Is there any way to get warned of a quake before I feel the shaking?
There’s a free app available for iOS and Android devices called MyShake, which was developed by UC Berkeley and is provided in partnership with the California Governor’s Office of Emergency Services.
MyShake receives messages from ShakeAlert, the U.S. Geological Survey’s early warning system. For people a bit farther from a quake’s epicenter, the system uses the lightning speed of today’s telecommunications system to send an early warning of incoming shaking, which moves at the slower speed of sound in rock.
Many users can get pivotal seconds of warning that shaking is incoming, or at least confirmation that what they are already feeling is in fact an earthquake. That can give people time to drop, cover and hold on, or take other appropriate action, like setting down a kitchen knife.
How should I secure my home?
Head to the hardware store and look for ways to properly strap bookcases to walls, find quake-friendly ways of hanging glass picture frames, and secure TVs to the wall so they don’t tip over in an earthquake.
Water heaters are also important to properly strap down, as doing so reduces the risk of a fire.
You should also check to see if your home or apartment needs a retrofit.
There’s a common type of defect in many older California homes — particularly those built before 1979 that have a handful of steps above the ground.
They are at risk because they’re attached to the foundation by a short flimsy wall known as a “cripple wall,” which leaves the house vulnerable to snapping off the foundation when shaken. Fixing this issue costs about $5,000 in Southern California and $6,000 in Northern California.
Grants are available through the California Residential Mitigation Program to help offset the cost of this type of retrofit. The registration period deadline has been extended to Friday. Applications can be filed at earthquakebracebolt.com.
Owners can apply for up to $3,000 in grant funding. For the first time, the program is now allowing owners to get funding for homes that they rent, “allowing landlords to apply for this retrofit grant opportunity for their investment properties,” according to the program.
Apartment owners should also look to see if their buildings need a retrofit. Many in California are seismically flimsy “soft-story” apartment buildings.
The term applies to apartment buildings built decades ago in which the bottom floor has room for a carport, garage or retail shop. In these buildings, the ground floor can be held up by flimsy, skinny poles that can collapse when shaken side-to-side in an earthquake.
See if you live in a tsunami hazard zone
California’s recent brushes with tsunami warnings have led officials to reiterate the need for residents to know if they live, work or otherwise frequent hazard zones.
The California Geological Survey has a map showing the zones, and knowing if you frequent any of them can help you mentally prepare for the need to evacuate should a tsunami warning sound. Importantly, knowing now can also let you know if it’s even necessary to evacuate.
During a recent tsunami warning, some residents in Northern California living in coastal areas — but at an elevation high enough to be safe from any tsunami — unnecessarily evacuated, and actually fled into lower-lying areas that were at risk for flooding.
In other areas, such as in Berkeley, some residents mistakenly thought it was impossible for a tsunami to enter San Francisco Bay, and argued against following city evacuation orders.
Experts say there is more work to do in educating people about tsunami risk.
What makes California so exposed to earthquakes?
The same geological forces that have helped shape California’s dramatic mountains and shoreline — letting us ski and surf on the same day — are the same as those that pose future seismic risk.
Despite its notoriety, California actually is the second-most seismically active state in the nation — Alaska is No. 1 — “but because we have about 40 million people in the state, we are No. 1 in seismic risk,” Lancaster said. A single earthquake in California could potentially cost hundreds of billions of dollars.
And the last mega-earthquakes — those on the scale of magnitude 7.8 or 7.9 — haven’t happened in modern times. The last earthquake of that magnitude struck Northern California in 1906, destroying much of San Francisco. An earlier one rocked Central California and Southern California in 1857, when the region was still sparsely populated.
Areas that can experience the most devastating shaking in earthquakes are generally areas right along California’s active faults, Bohon said. That includes places in Southern California and the San Francisco Bay Area, according to the California Geological Survey’s updated map of earthquake shaking potential.
What are officials doing?
California is working to better prepare itself against earthquakes. On Wednesday, the California Governor’s Office of Emergency Services broke ground on a new campus in Costa Mesa to act as a headquarters for Southern California disasters and emergencies. The office’s current headquarters is in Mather, just outside of Sacramento.
And on May 6, the Los Angeles County Board of Supervisors unanimously passed a new law requiring the seismic retrofit of certain high-rise concrete buildings that are either owned by the county or in unincorporated areas, where 1 million people live. The county set a deadline for retrofits to be done within 20 years.
But much remains to be done. While some local governments across California have required retrofits of older, seismically risky buildings, many others have not. There remain questions about how resilient water supply and utility systems will be after a big earthquake.
One big concern is the risk of fire following an earthquake, and whether firefighters will have access to adequate water.
“Anywhere in California can experience strong earthquake shaking,” Bohon said. “So it’s really important for you to know to do.”
The post What do you do when an earthquake hits? ShakeOut drill provides pivotal tips appeared first on Los Angeles Times.
