More than 10 million people across California will practice how to drop, cover and hold on at precisely 10:16 a.m. Thursday as part of the state’s annual earthquake drill, The Great California Shakeout.
The event comes as researchers warn a large-scale earthquake in San Diego County is long overdue.
Earthquake Preparedness
These tips come from the American Red Cross.
If you are inside when the quake hits:
• Drop, cover and hold on. Move as little as possible.
• If you are in bed, stay there, curl up and hold on. Protect your head with a pillow.
• Stay away from windows to avoid being injured by shattered glass.
• Stay indoors until the shaking stops and you are sure it is safe to exit. When it is, use stairs rather than the elevator in case there are aftershocks, power outages or other damage.
• Be aware that fire alarms and sprinkler systems frequently go off in buildings during an earthquake, even if there is no fire.
If you are outside when the quake hits:
• If you are in a vehicle, pull over to a clear location and stop. Avoid bridges, overpasses and power lines if possible. Stay inside with your seatbelt fastened until the shaking stops. Then, drive carefully, avoiding bridges and ramps that may have been damaged.
• If a power line falls on your vehicle, do not get out. Wait for assistance.
• If you are in a mountainous area or near unstable slopes or cliffs, be alert for falling rocks and other debris. Landslides are often triggered by earthquakes.
For more information, go to preparesandiego.org.
The last major temblor to hit the county was 214 years ago. A magnitude-6.5 quake jolted the region on Nov. 22, 1800.
Since then, shaking has been relatively quiet, with the exception of some distant quakes, including the Easter earthquake in Mexico in 2010.
But the county is surrounded by active faults capable of unleashing large quakes up to a magnitude 7 or higher, including the San Jacinto, Elsinore and several offshore faults.
The biggest concern is the Rose Canyon fault because it cuts through the heart of the city, stretches across La Jolla and continues north along the coast.
“It’s been about 400 years since the last earthquake,” said Thomas Rockwell, a geological sciences professor at San Diego State Univeristy. “And the slip-rate is about 2 millimeters a year, so there’s enough elastic strain built up for something in the high 6’s on that fault.”
Rockwell and his team recently excavated a section of the fault in Old Town to study prehistoric earthquakes.
“We found that we have more frequent quakes on the Rose Canyon fault than we had thought,” he said. “So it looks like the average recurrence is more like 500 to 1,000 years on the Rose Canyon rather than 1,000 to 2,000 years."
A major quake on the Rose Canyon or other nearby faults could cause significant damage and cut off water supplies, electricity and transportation across the region.
“If it happened at 5 o’clock and we had the maximum credible earthquake along the Rose Canyon, we might anticipate somewhere around 57 deaths,” said Holly Crawford, director of San Diego County’s Office of Emergency Services.
Crawford said modeling data from U.S. Geological Survey and the Federal Emergency Management Agency also shows that a magnitude-6.9 would cause approximately 2,000 people to be injured and displace 5,000 households.
She urges residents to prepare for the next quake by creating a family emergency plan and registering their mobile phones with the county’s mass notification system at ReadySanDiego.org.
“And that will give you information at your fingertips during a disaster: where the shelters are located, what the disaster perimeter is, where you can go for help," Crawford said.
