Can you store emergency water in a garage or car?
The short answer
A garage only works if it stays between 50 and 70°F and the water is kept away from gasoline, pesticides and other chemicals. Those are the CDC's storage rules, and a hot garage breaks them. A car is too hot for your main supply, but keeping a small amount in it is still smart, as long as you swap it often.
Where to keep your water
| Spot | Good for your main supply? | Why |
|---|---|---|
| Closet, pantry or under a bed | Yes | Cool, dark and away from chemicals. |
| Dry basement | Usually | Often the coolest place in the house. Keep it away from cleaners, paint and pesticides. |
| Garage | Only if it stays cool | Fine if it stays at 50–70°F and the water is away from gasoline, pesticides, paint thinner and cleaners. |
| Attic | No | Rarely stays in the 50–70°F range. |
| Car | No, small supply only | Heats up fast in the sun. Keep a few bottles for when you're on the road. |
The rules your water needs
The CDC says to keep stored water:
- at a cool temperature, between 50°F and 70°F
- away from direct sunlight
- away from toxic substances, such as gasoline or pesticides
The bottled water industry group IBWA gives the same advice, and adds paint thinner, household cleaners and dry cleaning chemicals to the list. Many garages hold all of those.
If the garage is your only space
- Check the temperature. Put a cheap thermometer next to the water on a hot afternoon. If it reads above 70°F, find another spot for most of your water.
- Keep chemicals on the other side. Gas cans, paint, pesticides, cleaners and car fluids go nowhere near your water.
- Keep it out of the sun. Away from windows and the garage door.
- Label and replace it. Write the date on each container and replace water you filled yourself every 6 months. Our label maker prints the labels for you.
Short on space indoors? Our guide to water storage for small spaces shows where water fits in a home without a garage.
Keep some water in your car
Emergencies don't wait until you're home. Tennessee's state emergency guide says a car kit should have food, water, first aid supplies, flares, jumper cables and seasonal supplies at a minimum. Alameda County suggests keeping two cases of water in the trunk.
The problem is heat. The National Weather Service says a car's dashboard and seats can reach 180°F to over 200°F in the sun. No agency gives a replacement schedule for water kept in a car, so here's our rule of thumb:
- Keep it small. Enough for the people who ride with you for a day, not your whole home supply.
- Use sealed, store-bought bottles, in the trunk, out of the sun.
- Swap them every season. Drink the old bottles and put in new ones when the weather changes.
- Watch for freezing. Water expands as it freezes and can split a full bottle in winter.
Never leave people or pets in the car
Ready.gov says never to leave people or pets in a closed car on a warm day. The National Weather Service warns that a parked car can get dangerous even when it's in the 70s outside, and that cracking the windows doesn't help much. Read more in our heat wave guide.
Work out how much you need
The water storage calculator tells you how much water your household needs, how many containers that is and how much floor space they take, so you know before you choose a spot.