California's emergency kit: 3 days, ready for the big one
Cal OES asks Californians to be ready for at least 3 days at home without water or electricity. Its Family Readiness Guide sets the floor at 1 gallon of water per person per day, and its Earthquake Readiness Guide goes further with a stay box of 3 gallons per person per day. Turn on MyShake or Android Earthquake Alerts so your phone warns you seconds before shaking reaches you.
What this means for your household
Set your household size to see the days, water and food the California advice adds up to.
Be ready for at least 3 days at home without water or power.
Drinking water for 2 people. Official figure: at least 1 gallon (about 3.8 L) per person per day; Cal OES's earthquake stay box plans for 3 gallons.
Person-days of food to cover (2 × 3). Pick food that needs no fridge and little or no cooking.
What Cal OES says to keep at home
Plan to manage at home for at least 3 days without running water or power. A go-bag can double as your stay box if you shelter in place.
- Water: at least 1 gallon per person per day for 3 days. The Earthquake Readiness Guide's stay box plans for 3 gallons per person per day
- Non-perishable food that needs no cooking, and a manual can opener
- A flashlight, a battery or hand-crank radio, and spare batteries
- A first aid kit and extra prescription medicines
- Sturdy shoes and work gloves near the bed, for broken glass after a quake
- A whistle, a wrench to shut off gas if you smell a leak, and a fire extinguisher
- Copies of IDs and insurance papers, and some cash
- Supplies for children, older relatives and pets
How California warns you
- MyShake is California's free earthquake warning app. It can give up to 10 to 20 seconds' notice before shaking arrives.
- Android phones in California get Android Earthquake Alerts built in, with no app needed.
- Wireless Emergency Alerts (WEA) reach phones in the area at risk for earthquakes, wildfires and other emergencies. You don't need to sign up.
- When a warning comes: Drop, Cover and Hold On. If you use a wheelchair or walker: Lock, Cover and Hold On.
- Cal OES suggests learning what each alert looks and sounds like before you need it.
California-specific steps
- Secure heavy furniture, TVs and water heaters to the wall so they don't fall in shaking.
- Know how to shut off gas, water and electricity, and only shut off gas if you smell or hear a leak.
- Keep a smaller kit in the car and at work: a big quake can keep you away from home.
- Wildfire areas: keep the go-bag by the door during fire season and leave as soon as you're told to.
- Agree a meeting place and an out-of-state contact, since local phone lines may be jammed.
Go beyond the minimum: what we recommend
Official lists cover the basics. These are the gaps we see most often when an emergency lasts longer than expected.
- Build toward 7 days of water and food, even if the official minimum is 3. Outages often last longer than planned.
- Keep paper and digital copies of IDs, insurance and prescriptions, so you can prove who you are and get medicines.
- Write the expiry date on everything and check the kit every 6 months, so it doesn't quietly go out of date.
- Plan for phone power: a charged power bank, plus a solar panel or car charger for longer outages.
- Save offline maps of your area and agree a meeting point, in case the mobile network is down.
- An offline survival guide on your phone: HAVEN tracks your kit and expiry dates and works with no signal.Download HAVEN free
Numbers to write down
- 911 · Emergency services
- MyShake · Earthquake warning app
- 1-800-621-3362 · FEMA disaster assistance
Keep a paper copy: your phone may be flat when you need it.
Your kit, ready when the network isn't
HAVEN tracks your stay box in gallons and days for your household, reminds you before water and food expire, and keeps offline first aid and shut-off guides on your phone for when the network is down after a quake.
- Coverage in days for your household
- Expiry reminders
- Offline guides and AI
- Free to start, no account needed
How California compares
California: 3 days. The national advice from FEMA is at least 3 days. Read the United States guide or compare every country.
California preparedness FAQ
How many days of supplies does California recommend?
At least 3 days. Cal OES asks households to be ready to stay at home for 3 days without water or electricity.
How much water should I store for an earthquake in California?
At least 1 gallon per person per day, per Cal OES's Family Readiness Guide. Its Earthquake Readiness Guide plans a stay box with 3 gallons per person per day, which covers cooking and washing too.
What is a stay box?
A kit of water, food and supplies to shelter at home. Cal OES notes a go-bag can become your stay box if you need to stay put.
Does MyShake really warn before an earthquake?
It warns before shaking reaches you, not before the quake starts. Depending on how far you are from the epicentre, that can be up to 10 to 20 seconds.
Do I need to download an app to get earthquake alerts?
Not on Android, which has earthquake alerts built in. iPhone users should install MyShake. Wireless Emergency Alerts reach every compatible phone.
Official sources
- Earthquake Preparedness (Cal OES)
- Family Readiness Guide (Cal OES, PDF)
- Essential earthquake safety tips (Cal OES News)
- Preparedness Month 2026 (Cal OES News)
- April is Earthquake Preparedness Month (Cal OES News)
This page summarises official advice and is not a substitute for it. Always follow the instructions of your local emergency services. Last checked 2 November 2026.