California Survival Guide: Earthquakes, Wildfire and Power Shutoffs

Scientists cannot predict the day of an earthquake. What they publish are forecasts: the chance of a quake of a given size within a set number of years. California's official long-term forecast is UCERF3, released in 2015 by the U.S. Geological Survey (USGS) and its partners. The benchmark is magnitude 6.7, the size of the 1994 Northridge earthquake, over 30 years.

The USGS also puts it as a rate: California averages about one M6.7 earthquake every 6.3 years. In the Bay Area, the Hayward and Rodgers Creek faults have the highest chance of any single fault system because they run under dense cities.

Newer Bay Area numbers: in September 2026, news outlets reported a new USGS study that raises the Bay Area's 30-year chance of an M6.7 or larger quake from 72 to 74 percent, with the Hayward and Rodgers Creek faults at 34.3 percent. We could not open the USGS report itself, so the table above shows the last figures USGS published directly.

We could not confirm a UCERF3 figure for the Los Angeles region alone. The often-quoted 67 percent figure for Los Angeles comes from the earlier 2008 forecast, not UCERF3. Region boundaries also change between studies, so do not compare numbers from different forecasts directly. The takeaway is the same everywhere in the state: plan as if a damaging quake will happen while you live here.

California has a public earthquake early warning system. ShakeAlert, run by the USGS with partners including the California Governor's Office of Emergency Services (Cal OES), uses more than 1,300 seismic sensors across California, Oregon and Washington. It spots a quake that has already started and sends an alert, which can arrive seconds before the shaking does. How much warning you get depends on how far you are from the epicenter. Close to the epicenter you may get little or no warning.

It works. When a magnitude 5.2 quake hit near Julian in San Diego County on April 14, 2025, almost 700,000 phones received MyShake warnings, according to Cal OES, and millions more got alerts through Wireless Emergency Alerts and Google. Because the first magnitude estimate is rough, you may sometimes get an alert and feel nothing.

⚠ Do not run outside during shaking, do not stand in a doorway, and ignore the "triangle of life" advice. Outer walls and windows often fail first, and in a modern home a doorway is no stronger than any other spot. Do not lie down next to a car either, because the car can shift and crush you.

Most earthquake injuries come from things falling, not buildings collapsing. In the 1994 Northridge earthquake, 55 percent of injuries came from falling furniture or objects, according to the Earthquake Country Alliance.

Many older California houses sit on a raised wood foundation over a crawl space. In a strong quake they can slide off that foundation. The fix is a seismic retrofit: bolting the house to its foundation and bracing the short crawl space walls (cripple walls). The California Residential Mitigation Program (CRMP) says this usually costs $3,000 to $7,000 when a contractor does it, and less if you do it yourself.

Income limits change from year to year. When the program opened in 2025, the California Department of Insurance listed $89,040 a year. The CRMP program page now lists $94,480. Go by the figure on the program page when you register.

Most homes that burn are not caught by a wall of flame. El Dorado County's wildfire office says about 60 to 90 percent of homes lost in wildfires are ignited by embers, which are wind-blown burning bits that land in vents, gutters, dead plants and gaps. Defensible space and home hardening are both about giving embers nothing to catch on.

State law requires defensible space out to 100 feet, or to your property line if it is closer, in the areas it covers. Local rules can be stricter. Los Angeles County Fire says some properties need up to 200 feet and asks that woodpiles and propane tanks sit at least 30 feet from buildings.

California uses standard evacuation terms statewide, so an alert means the same thing in every county. Learn them now, because there is no time to look them up while a fire is moving.

Ready, Set, Go is the state and county fire departments' approach: Ready means defensible space and a hardened home, Set means a plan and a packed bag, Go means leaving early. Palo Alto Fire says to leave as soon as officials recommend it, and not to wait for an order if you are unsure. Los Angeles County Fire says always follow evacuation orders and do not try to fight the fire yourself.

⚠ Leaving early is the single most protective choice in a wildfire. Roads clog and smoke cuts visibility quickly. If you are trapped, call 911 and give your location, knowing help may be slow to arrive. Turn on lights so rescuers can find you.

During dangerous fire weather, utilities may switch off power to some areas so their equipment cannot start a fire. This is called a Public Safety Power Shutoff (PSPS). The California Public Utilities Commission (CPUC) calls it a last resort. Utilities that can do this include PG&E, Southern California Edison, SDG&E, Liberty Utilities, Bear Valley Electric Service and PacifiCorp. Shutoffs follow forecasts of high wind and low humidity, dry ground, and National Weather Service Red Flag Warnings. In Southern California, Santa Ana winds can blow palm fronds and branches into power lines.

How much notice you get depends on your utility and on the forecast. SDG&E says alerts usually begin 24 to 48 hours ahead. PG&E says that when forecasts change, the first alert may come the same day the power goes off. Plan as if you may have only a few hours.