How should you store emergency water, and for how long?

Short answer. Commercially bottled water, left sealed in its original container, is the safest emergency supply ¹². If you fill your own, use food-grade containers that are not glass, clean and sanitize them first, label them with the date, and keep them cool (50-70 °F, about 10-21 °C) and out of sunlight ¹. U.S. agencies say to replace home-filled water every six months ¹².

Why does the container matter as much as the water?

Stored water is only as safe as the vessel holding it. The CDC states that "it is best to use FDA-approved food-grade water storage containers" and notes that such containers "will not transfer toxic substances into the water" ¹. If you cannot get one, it asks for a container with a top that closes tightly, made of durable, unbreakable materials (not glass) and, if possible, with a narrow neck or opening so you can pour water out of it ¹.

The CDC also rules out any container that previously held liquid or solid toxic chemicals, naming bleach and pesticides as examples ¹. FEMA's older guidance gives the same rule in fewer words: "Never use a container that has held toxic substances" ⁵.

Is store-bought bottled water better than filling your own?

Yes, according to both the CDC and Ready.gov. The CDC calls commercially bottled water the safest and most reliable emergency source ¹, and Ready.gov advises keeping it in its "sealed original container" in a cool, dark place ².

Part of the reason is regulation. In the United States, the FDA regulates bottled water as a food under the Federal Food, Drug, and Cosmetic Act ⁴. Bottlers must follow "standard of identity" rules that define each type of water, "standard of quality" limits on chemical, physical, microbial and radiological contaminants, and current good manufacturing practice rules covering plant design, bottling procedures and record keeping ⁴.

The CDC still asks you to check the expiration date on store-bought water ¹.

How do you prepare a container you fill yourself?

The CDC gives a six-step routine for cleaning and sanitizing a container before filling it ¹:

1. Wash the container with soap and rinse it thoroughly.
2. Mix 1 teaspoon of unscented liquid household chlorine bleach (5%-9% sodium hypochlorite) into 1 quart (4 cups, about 0.95 L) of water.
3. Pour the solution in, close the container tightly and shake so it touches every inside surface.
4. Wait at least 30 seconds, then pour the solution out.
5. Let the container air-dry.
6. Fill it with clean water and seal it.

Ready.gov gives the same sanitizing ratio: one teaspoon of non-scented liquid household chlorine bleach to a quart of water, after scrubbing with dish soap ².

Then label each container as drinking water and write the date you stored it ¹. FEMA's guidance also says to seal containers tightly, label them and store them in a cool, dark place ⁵.

Where should you keep stored water?

The CDC gives three conditions ¹:

Ready.gov repeats "cool, dark place" for both bottled and home-filled water ². In practice, this rules out a garage shelf next to fuel cans or a sunny window ledge.

How long does stored water last?

The guidance depends on who filled the container:

• Home-filled water: replace every six months, according to the CDC ¹ and Ready.gov, which specifies water "that has not been commercially bottled" ². FEMA's older brochure said to "rotate water every six months" without making that distinction ⁵.
• Commercially bottled water: the CDC says to check the expiration date ¹. Ready.gov's water page gives no replacement interval for sealed bottled water ².
• Canada: the federal Get Prepared program asks households to replace items that might expire, "food, water, batteries and medications," at least once a year ⁶.

Should you add bleach to water before storing it?

The CDC's storage page does not give a bleach dose for water you store; it says bleach can be used to disinfect water "if necessary" and points to its separate water-safety guidance ¹.

When water does need disinfecting, for example after a boil-water notice or when it comes from an untreated source, the EPA's current table depends on the strength of the bleach ³:

The EPA says to double the amount if the water is cloudy, colored or very cold, to stir and let it stand for 30 minutes, and to check for a slight chlorine odor; if there is none, repeat the dose and wait another 15 minutes ³. Cloudy water should first settle and be filtered through a clean cloth, paper towel or coffee filter ³. Ready.gov gives a single figure for treating drinking water: 1/8 teaspoon of bleach per gallon, stirred and left 30 minutes ².

Only use plain, unscented chlorine bleach for either sanitizing or disinfecting ¹².

What official agencies recommend

The core advice is consistent across U.S. agencies, with differences in detail:

• CDC (United States): FDA-approved food-grade containers, not glass; sanitize with 1 teaspoon of bleach per quart of water; store at 50-70 °F, out of sunlight, away from fuels and pesticides; label and date; replace home-filled water every six months; aim for at least 1 gallon per person per day for 3 days, and 2 weeks if possible ¹.
• Ready.gov / FEMA (United States): keep bottled water sealed in its original container; use food-grade containers otherwise; replace water that was not commercially bottled every six months ².
• EPA (United States): bleach dose by concentration, 8 drops per gallon at 6% and 6 drops at 8.25% ³.
• FEMA, older guidance (2004): listed glass, fiberglass and enamel-lined metal alongside plastic, said plastic containers such as soft-drink bottles were best, and gave 16 drops of 5.25% bleach per gallon ⁵. The CDC now advises against glass ¹, and the EPA's current doses are lower ³. Where the two differ, follow the current pages.
• Canada: 4 litres per person per day, small bottles that can be carried easily, and replacement of water and other perishables at least once a year ⁶.

Frequently asked questions

Can I reuse milk jugs or juice bottles?

The CDC asks for FDA-approved food-grade containers where possible, and otherwise a durable container with a tight-fitting lid ¹. It does not list specific household bottles, so a container that cannot be sealed tightly or cleaned thoroughly does not meet its criteria. Never reuse a container that held bleach, pesticides or other chemicals ¹.

Does bottled water expire?

The CDC tells you to check the expiration date on store-bought water ¹ and to keep it sealed in its original container in a cool, dark place ². Ready.gov's six-month rule applies to water that was not commercially bottled ².

Is glass a good container for stored water?

The CDC asks for durable, unbreakable materials and specifies "not glass" ¹. FEMA's 2004 brochure accepted glass ⁵, but the current CDC page is the more recent guidance.

How much water should I store in total?

The CDC says at least 1 gallon (3.8 L) per person per day for 3 days, and a 2-week supply if possible, with more for pregnant women, sick people, pets and hot climates ¹. Canada uses about 4 litres per person per day ⁶. See our guide on water per person for other countries.

What if my stored water smells odd after six months?

Replace it, as the CDC and Ready.gov advise for home-filled water at six months anyway ¹². If water is all you have, the EPA's bleach table above gives the disinfection dose ³.

Get the right supplies in one place

Water appears on every official emergency kit list. Your Phaenyx plan counts the litres for your household from your national agency's figure. Build your Phaenyx plan.

Sources

1. Centers for Disease Control and Prevention (CDC) — How to Create an Emergency Water Supply — https://www.cdc.gov/water-emergency/about/how-to-create-and-store-an-emergency-water-supply.html (accessed 2026-10-20)
2. Ready.gov (U.S. Department of Homeland Security / FEMA) — Water — https://www.ready.gov/water (accessed 2026-10-20)
3. U.S. Environmental Protection Agency (EPA) — Emergency Disinfection of Drinking Water — https://www.epa.gov/ground-water-and-drinking-water/emergency-disinfection-drinking-water (accessed 2026-10-20)
4. U.S. Food and Drug Administration (FDA) — Bottled Water Everywhere: Keeping it Safe — https://www.fda.gov/consumers/consumer-updates/bottled-water-everywhere-keeping-it-safe (accessed 2026-10-20)
5. Federal Emergency Management Agency (FEMA) — Food and Water in an Emergency (archived 2004 version) — https://webharvest.gov/peth04/20041015031112/http://www.fema.gov/rrr/foodwtr.shtm (accessed 2026-10-20)
6. Government of Canada (Canada.ca, Get Prepared) — Emergency kits — https://www.canada.ca/en/services/policing/emergencies/preparedness/get-prepared/emergency-kits.html (accessed 2026-10-20)