How Much Water to Store for Emergencies: A Simple Plan

Quick answer

Store at least 1 gallon (3.8 L) per person per day (CDC, Ready.gov).
Keep 3 days of water in your go-bag and 2 weeks at home (Red Cross).
Store a 2-week supply for each pet (CDC).
Replace water you bottle yourself every 6 months. Follow the date on store-bought water.

Water runs out faster than food in most emergencies. A storm, quake or water main break can cut off safe tap water for days. The numbers below come from the CDC, Ready.gov (FEMA) and the American Red Cross.

How much water each person needs

The baseline is simple. The CDC and Ready.gov say to store at least 1 gallon per person per day. That gallon covers drinking and basic sanitation.

Ready.gov says a normally active person needs about three-quarters of a gallon of fluid a day. The rest of the gallon goes to cooking, brushing teeth and washing hands. It does not cover showers, laundry or flushing.

Store more for these people

Children, nursing mothers and sick people. Ready.gov says they may need more water.
Pregnant women. The CDC says to consider storing extra.
Hot weather. Ready.gov says water needs can double in very hot temperatures. Plan up to 2 gallons per person per day if you live somewhere hot.

Your household totals

The Red Cross gives two targets. Keep a 3-day supply for evacuation. Keep a 2-week supply at home.

People	3 days	2 weeks	2 weeks in hot weather
1	3 gallons	14 gallons	up to 28 gallons
2	6 gallons	28 gallons	up to 56 gallons
3	9 gallons	42 gallons	up to 84 gallons
4	12 gallons	56 gallons	up to 112 gallons
5	15 gallons	70 gallons	up to 140 gallons
6	18 gallons	84 gallons	up to 168 gallons

A gallon of water weighs about 8.3 pounds. So a 3-day supply for one person weighs about 25 pounds. Keep the go-bag amount to what you can carry, and store the rest at home.

If 2 weeks feels like too much, start with 3 days. Add one case or jug each time you shop.

How much water to store for pets

The CDC’s pet kit list calls for a 2-week supply of water for each animal. The CDC does not give one number for every pet, because needs vary by size and type.

Work out your own number:

Fill your pet’s bowl with a measured amount of water in the morning.
Top it up through the day and note each amount you add.
Measure what is left the next morning. The difference is one day’s use.
Multiply by 14 for a 2-week supply.
Add extra for hot weather and for rinsing bowls.

Pack a non-spill water dish too. The CDC lists one in its pet kit.

Bottled water or tap water

The CDC says unopened, commercially bottled water is the safest choice. It is sealed, dated and easy to rotate.

Filling your own containers from the tap costs less. It works well if your home is on a public water system and there is no water advisory. Fill your containers before a storm, while the water is still safe.

If you are not sure your tap or well water is safe, treat it before you store it. The CDC notes that well water can be contaminated during floods. See our guide on how to purify water in an emergency for the steps.

	Store-bought bottled water	Water you bottle yourself
Cost	Higher	Low
Safety	Safest choice (CDC)	Safe if the water and container are clean
How long to keep	Until the expiration date	Replace every 6 months
Storage	Sealed, in the original container	Sanitized food-grade container, tight lid

Which containers to use

Good choices

Commercially bottled water, left sealed until you need it.
FDA-approved food-grade water storage containers. The CDC says these are best.
If you can’t get those, a container that is durable, unbreakable and has a tight lid. The CDC suggests a narrow opening so you can pour without dipping.
Clean 2-liter plastic soda bottles. FEMA lists these as a good reuse option.

Do not use

Glass. The CDC says not to use it. FEMA notes it is heavy and can break.
Milk or juice jugs and cartons. FEMA says not to reuse them for water.
Any container that held toxic chemicals, such as bleach or pesticides (CDC).

How to clean containers before you fill them

These are the CDC’s steps for containers you fill yourself.

Wash the container with soap and water. Rinse it well.
Mix 1 teaspoon of unscented liquid household bleach into 1 quart (4 cups) of water. The bleach should be 5% to 9% sodium hypochlorite.
Pour the mix into the container. Close it and shake so the mix touches every inside surface.
Wait at least 30 seconds. Then pour it out.
Let the container air-dry.
Fill it with clean water and close it tightly.

The CDC warns never to mix bleach with ammonia or any other cleaner. Open a window while you work.

Where and how to store it

Label it. Write “drinking water” and the date on each container (CDC).
Keep it cool. The CDC says 50°F to 70°F (10°C to 21°C).
Keep it dark. Store it out of direct sunlight.
Keep it away from chemicals. Do not store it near gasoline or pesticides (CDC).
Spread it out. Keep some in the go-bag, some in the car and the rest at home.

When you open a container, use a clean cup or scoop each time. The CDC says not to touch the water or the inside of the container with your hands.

How often to replace stored water

Store-bought water: follow the expiration date (CDC).
Water you bottled yourself: replace it every 6 months (CDC, Ready.gov).

Pick two easy dates, such as when the clocks change in spring and fall. Use the old water for plants or cleaning. Then wash, sanitize and refill the containers.

If your stored water runs low

Do not ration drinking water unless officials tell you to (Ready.gov, FEMA). Drink what you need today, and look for more for tomorrow.

Hidden water in your home

The CDC and FEMA list these sources inside your home. Where they differ, we note it.

Your water heater tank. Use only the tank that feeds your faucets and showers, not one that heats radiators (CDC).
Water in your pipes. FEMA says to open the highest faucet in the home to let air in. Then collect water from the lowest faucet.
Ice cubes made from safe water (CDC).
Toilet tank water, not the bowl, as a last resort. The CDC allows it only if it is clear and has no cleaner in it. FEMA’s guide says not to use it, so treat it before drinking.
Liquid from canned fruits and vegetables (CDC).

Turn off the power or gas before you drain a water heater. Our urban survival skills guide walks through the full steps.

If there is a risk of floodwater or a broken main, the CDC says you may need to shut your home’s main water valve. That keeps bad water from getting into your pipes. Find the valve now and tag it.

Water you should not drink

Pool and spa water. The CDC says it is fine for washing and cleaning, but not for drinking.
Water from radiators or waterbeds (FEMA).
Floodwater. FEMA says not to drink it.
Water with fuel or toxic chemicals in it. The CDC says boiling or disinfecting cannot make it safe.

Common mistakes

Storing 3 days of water and calling it done. Aim for 2 weeks at home.
Forgetting pets, babies, nursing mothers and hot weather.
Reusing milk jugs or containers that held chemicals.
Storing water in a hot garage next to gas cans.
Never rotating home-filled water.
Packing more water in the go-bag than you can carry.

Water storage checklist

Water is item one in our list of must-have survival kit items. Pair your water with the food plan in our long-term food storage guide.

Sources

How to Create an Emergency Water Supply — CDC
How to Find Clean Water in an Emergency — CDC
Build a Pet Disaster Preparedness Kit — CDC
Cleaning and Sanitizing with Bleach After an Emergency — CDC
Water — Ready.gov (FEMA)
Survival Kit Supplies — American Red Cross
What are emergency water sources if I’m running out of clean water? — FEMA
Food and Water in an Emergency (archived) — FEMA