How to Build a California Earthquake Go-Bag: What Cal OES and USGS Actually Recommend

A major earthquake can cut off power, water and road access within seconds, with no warning beyond the few seconds ShakeAlert gives you. Emergency managers at the California Governor's Office of Emergency Services and seismologists at the U.S. Geological Survey are consistent on one point: the first 72 hours after a significant quake are when you're most likely to be on your own, before outside aid reaches your neighborhood. A go-bag built before the shaking starts is the single most concrete thing a California household can do to close that gap.

Related: California Earthquake Go-Bag Checklist: What Emergency Officials Actually Say to Pack · Your California Go-Bag Checklist: What Emergency Officials Actually Recommend You Pack

What to Pack: The Core List

Cal OES guidance centers on supplies for at least 72 hours per person, though the agency now recommends planning for up to two weeks if you can manage it. Start with water: one gallon per person per day is the standard figure, which means a family of four needs at least 12 gallons for the minimum three-day supply. Store-bought sealed containers are simplest; if you fill your own, replace them every six months.

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California Earthquake Go-Bag Checklist: What Emergency Officials Actually Say to Pack Your California Go-Bag Checklist: What Emergency Officials Actually Recommend You Pack How to Build a California Go-Bag That Will Actually Get You Out the Door

Food should be non-perishable and require no cooking or minimal preparation, since gas lines may be shut off and open flames may be unsafe after a quake. Think canned goods, dried fruit, nuts, peanut butter, and protein bars. Pack a manual can opener, because that gets forgotten more than almost anything else.

Beyond food and water, the core items Cal OES recommends include: a battery-powered or hand-crank NOAA weather radio (cell networks often jam or fail); a first-aid kit with any prescription medications in at least a week's supply; copies of important documents in a waterproof bag or folder (insurance cards, IDs, prescriptions, a household contact list written on paper); cash in small bills, since ATMs and card readers go down with the power; a flashlight with extra batteries; sturdy closed-toe shoes kept next to each bed, because broken glass on the floor is one of the first hazards after shaking; dust masks or N95 respirators; and a wrench or plumber's pliers to shut off your gas meter if needed.

If your household includes infants, elderly family members, or people with disabilities or medical equipment that requires power, build those specific needs into the bag explicitly. Cal OES maintains a full household preparedness checklist at its website, and the specifics of medical and access-functional needs planning are covered in detail there.

Drop, Cover, Hold On: What to Do While the Ground Is Moving

The USGS and ShakeAlert program are unambiguous about the correct action during shaking: Drop, Cover, and Hold On. Get under a sturdy table or desk if one is nearby, cover your head and neck with your arms if not, and stay put until the shaking stops. Do not run outside during shaking. The majority of earthquake injuries come from falling objects and broken glass, not from buildings collapsing outright, and moving during shaking puts you directly in the path of those hazards.

If you're in bed, stay there and protect your head with a pillow. If you're outdoors, move away from buildings, power lines and trees, then crouch low and protect your head. If you're in a car, pull over away from overpasses, bridges, power lines and buildings, stay inside, and wait for shaking to stop before driving. The "doorway" advice you may have heard growing up is outdated and has been officially retired by USGS; a doorway offers no special protection in a modern building and leaves you exposed to more falling hazards than a proper covered position does.

The First Hours After Shaking Stops

The immediate post-shaking period is when decisions matter most. Once the ground is still, check yourself and others for injuries before moving. Expect aftershocks and be ready to drop and cover again. If you smell gas or hear hissing, leave the building immediately, leave the door open, and do not use any switches or open flames. Call your gas utility from outside or from a neighbor's house; do not re-enter until the utility clears it.

Check your home for visible structural damage before staying in it. Cracked foundations, leaning walls, or a shifted structure are reasons to get out and stay out until a building inspector clears it. Use your battery radio or a phone with a charged battery to get official information; in the immediate aftermath of a major quake, misinformation moves fast and official channels are the only reliable filter.

Text rather than call if cell service is limited. Texts use far less network capacity and are significantly more likely to go through during a congested post-disaster period. ShakeAlert, the USGS-backed early warning system now active across California, delivers warnings through the Wireless Emergency Alert system to most modern cell phones automatically, though signing up for your county's emergency alert system ensures you also get evacuation orders and shelter-in-place notices that come after the initial event.

See also: How to Build a California Go-Bag That Will Actually Get You Out the Door · California Earthquake Preparedness: What to Put in Your Go-Bag and What to Do When the Ground Starts Shaking

How to Sign Up for Earthquake and Emergency Alerts

California has no single statewide emergency text alert registration you have to opt into for ShakeAlert earthquake warnings, because those come automatically through Wireless Emergency Alerts to compatible phones as long as your phone's emergency alerts aren't turned off. Check your phone's notification or safety settings now to confirm you haven't disabled the "Emergency Alerts" or "Government Alerts" category.

For local evacuation orders, shelter-in-place notices and utility shutoff alerts, you do need to register with your county's system, because those are geography-specific and don't rely on the federal WEA system. Most California counties use platforms like Nixle, AlertSF, Genasys, or similar services. The Cal OES "MyHazards" tool at its official website can direct you to your county's specific sign-up page based on your address. Do this before an event, not during one.

Where to Keep the Bag and How to Maintain It

A go-bag that's buried under winter coats in a closet on the second floor is significantly less useful than one near an exit. Most preparedness guidance suggests keeping it near your most-used exit door, in a car, or in both places if your budget allows for a second smaller kit. A car kit is particularly valuable in California's commuter geography, where a major quake during working hours could leave you far from home.

Review and refresh the bag at least once a year. A common reminder is to do it when clocks change, though California's recent shift away from clock changes means you may want to pick a fixed date instead. Rotate food and water, check medication expiration dates, update document copies, and swap out children's clothing and supplies as kids grow. Batteries lose charge in storage, so check those too, or switch to a hand-crank or solar-charged radio to avoid that failure point entirely.

This is general information, not emergency or professional safety advice. Recommendations, specific supply quantities, and alert sign-up processes can be updated as official guidance evolves. Always verify current preparedness guidance with the California Governor's Office of Emergency Services at caloes.ca.gov, the U.S. Geological Survey's ShakeAlert program at usgs.gov/natural-hazards/earthquake-hazards/shakealert, and your county's official emergency management office.