Emergency Water Storage: How Much and What to Use
Ready.gov says to store at least 1 gallon of water per person per day for several days, for drinking and sanitation. CDC gives the same gallon but a number of days: at least 3, and 2 weeks if possible. This page shows both wordings, the containers they name and how often to rotate.
How much emergency water to store
The two federal pages read on 2026-11-02 use the same unit and different spans.
| Source | Amount per person | Days |
|---|---|---|
| Ready.gov | At least 1 gallon per day, for drinking and sanitation | "Several days", no number |
| CDC | At least 1 gallon per day | At least 3 days; a 2-week supply if possible |
A household of four on CDC's 3-day minimum is 12 gallons. A 2-week supply for the same four is 56 gallons. That is arithmetic on CDC's figures, not a recommendation from either agency. A 2-week supply is a lot of space, which is why many households start at the minimum and add to it.
Ready.gov also says a normally active person needs about three quarters of a gallon of fluid a day, counting water and other drinks. The 1 gallon figure leaves room for sanitation.
Who needs more
Both agencies say more may be needed. Ready.gov says children, nursing mothers and sick people may need more water, that a medical emergency may call for more, and that in very hot temperatures water needs can double. CDC's list of reasons to store more names pregnant women, sick people, pets and hot climates. Neither page read gives a quantity for pets: CDC includes pets in its list, and Ready.gov's kit page lists extra water for a pet without an amount.
What to store it in
- Store-bought bottled water. Ready.gov says to keep it in its sealed original container in a cool, dark place. CDC says to observe the expiration date on store-bought water.
- Your own containers. Ready.gov says to buy food-grade water storage containers. CDC says FDA-approved food-grade containers, or otherwise containers with a tight-closing top that are unbreakable (not glass), with a narrow neck if possible.
- Never a container that held toxic chemicals such as bleach or pesticides, says CDC.
CDC also gives a way to sanitize a container before filling: add 1 teaspoon of unscented liquid household chlorine bleach to 1 quart (4 cups) of water, cover and shake, wait at least 30 seconds, pour it out and let the container air-dry. It describes bleach with 5% to 9% sodium hypochlorite. Ready.gov gives the same 1 teaspoon per quart, after a wash with dish soap. Neither page read mentions milk jugs.
Where to keep it and how often to rotate
CDC says to keep stored water in a cool place, 50 to 70 degrees F, away from direct sunlight and away from gasoline or pesticides. For rotation, both pages give six months: CDC says to replace stored tap water every 6 months, and Ready.gov says the same for water that is not commercially bottled. Commercially bottled water follows its printed date. Neither page lists signs that stored water has gone bad.
Water in food-grade bottles that sits a long time is a reason to keep a note of the fill date on the container. That tip is ours, not the agencies'. For stored food, freeze-dried food shelf life explains what dates and storage temperatures mean, and a survival food kit comes with its own water need: the My Patriot Supply page lists how many gallons each kit takes to prepare, covered in the My Patriot Supply review. Add that to your totals.
When stored water runs out
CDC's page on finding clean water in an emergency lists these in-home sources:
- the water heater tank, only the tank that feeds the faucets and not radiator tanks in older homes
- melted ice cubes made with uncontaminated water
- the tank, not the bowl, of a toilet, only if the water is clear and has not been treated with toilet cleaners
- liquid from canned fruit and vegetables
CDC says pool and spa water is for hygiene and cleaning, not drinking, and that rain, streams, rivers, ponds, lakes and springs are options only after treatment, since they may carry livestock waste, sewage and chemicals. CDC says well water in a flood might also be contaminated. It adds that water contaminated by fuel or toxic chemicals cannot be made safe, and should not be drunk. Ready.gov refers only to "suspicious sources" such as cloudy tap water, streams and ponds, to be treated first.
Treating that water means boiling, tablets or bleach, with CDC's amounts on the page about water purification tablets, bleach and boiling. Filtering is covered under water filter vs purifier and in the hub for a survival water filter. A filter with no pump is described in gravity water filters.
A simple way to size the supply
Count the people, add pets and anyone who may need more, multiply by the days you want to cover, and then check the container sizes you can fit. Using CDC's figures, one person for 3 days is 3 gallons and for 2 weeks is 14 gallons. Count a standard 5-gallon jug as five days for one person on that arithmetic. Write the total next to the date you filled the containers, and set a reminder for six months later.
Space matters as much as amount. CDC says to keep water away from sunlight and from fuel and pesticides, so a garage shelf near a gasoline can is a poor spot, and a closet shelf is a better one. These placement notes are our reading of CDC's storage conditions.
Where water fits in a kit
Water is the heaviest item in any kit and the main reason a bug out bag holds a filter and a small bottle instead of gallons. A household supply at home is a different job. The emergency kit checklist lays out the home supply next to food and power. If an outage also runs a pump or well, what a solar generator can run lists load wattages for planning, and the Sawyer Squeeze review shows what one maker's filter page does and does not claim.
FAQ
How much water should I store per person?
Ready.gov says at least 1 gallon per person per day for several days. CDC says at least 1 gallon per person per day for at least 3 days, and a 2-week supply if possible.
Can I reuse plastic bottles?
The pages read do not discuss reusing soda or milk bottles. Ready.gov says to buy food-grade water storage containers, and CDC says FDA-approved food-grade containers or ones that are unbreakable with a tight-closing top. Containers that held bleach or pesticides are ruled out by CDC.
How often should I replace stored water?
CDC says to replace stored tap water every 6 months, and Ready.gov gives the same interval for water that is not commercially bottled. CDC says to observe the date on store-bought water.
What temperature should I store water at?
CDC says a cool place, 50 to 70 degrees F, out of direct sunlight and away from gasoline and pesticides.
Do pets count?
CDC's list of reasons to store more water includes pets, and Ready.gov's kit page lists extra water for a pet. Neither gives an amount.