How Much Water to Store Per Person for Emergencies

Updated September 22, 2026 · 6 min read

Water is the first thing to run out in almost every emergency, and the first thing people wish they had stored. Boil-water notices, burst mains, hurricanes, winter freezes and long power outages that stop well pumps can all leave a household without safe tap water for days. The good news is that storing water is cheap and simple once you know how much you need and how to keep it safe.

This guide walks through the standard recommendation, how to adjust it for your family, which containers to use, how to disinfect water and how often to rotate your supply.

The baseline: one gallon per person per day

Emergency management agencies in the United States, including FEMA’s Ready.gov program and the Red Cross, recommend storing at least one gallon of water per person per day. That gallon is meant to cover roughly half a gallon for drinking and half a gallon for basic food preparation and hygiene.

For how long? The minimum commonly recommended is a three-day supply, because it can take that long for help or services to reach everyone after a disaster. Many agencies encourage households to work toward a two-week supply if space allows, and that is a sensible target for anyone in an area prone to hurricanes, earthquakes or long winter outages.

So for a family of four:

3 days: 4 people x 1 gallon x 3 days = 12 gallons
2 weeks: 4 people x 1 gallon x 14 days = 56 gallons

Fifty-six gallons sounds like a lot, but it fits into a single 55-gallon drum plus a case of bottles, or about eleven 5-gallon containers stacked in a closet or garage.

How much water to store per person in your situation

One gallon is a minimum for healthy adults in a mild climate. Increase your numbers if any of these apply:

Hot weather. In high heat, water needs can double. If you live somewhere with hot summers, plan for more.
Children, nursing mothers and people who are ill generally need more water.
Medical needs. Some conditions and medications increase fluid needs. Ask your healthcare provider.
Pets. Dogs and cats need water too. A common rule of thumb is about one ounce per pound of body weight per day for dogs, but check with your veterinarian.
Powdered or dehydrated food. If your food stockpile relies on rice, beans, pasta or freeze-dried meals, you will need extra water to cook them.
Hygiene and sanitation. The one-gallon figure covers minimal hygiene. Washing dishes, cleaning and flushing toilets need much more, so plan separate non-drinking water for these tasks if you can.

A practical approach is to calculate your baseline, then add 25 to 50 percent as a buffer. Our guide Water Storage for Preppers goes deeper into calculating needs, building containers and setting up rain capture for non-drinking uses.

Choosing the right containers

The safest option for most people is commercially bottled water kept sealed in its original packaging. It is ready to drink, clearly dated and easy to rotate.

If you are filling your own containers, use:

Food-grade water storage containers, such as those sold for camping or emergency use. Look for containers labeled for drinking water; many are marked with the recycling code 1 (PETE) or 2 (HDPE).
Clean two-liter soda bottles, which are sturdy and seal well.
55-gallon food-grade drums for large supplies, paired with a pump or siphon for dispensing.

Avoid:

Milk and juice jugs. Milk proteins and fruit sugars are hard to clean out and can let bacteria grow, and the thin plastic tends to break down.
Containers that held chemicals or any non-food product.
Glass for large quantities, since it can break in an earthquake or if dropped.

Cleaning containers before use

Wash containers with dish soap and water and rinse thoroughly. Then sanitize them by swishing a solution of about one teaspoon of unscented liquid household chlorine bleach per quart of water around all inside surfaces, and rinse with clean water. Check the current recommendation from your public health agency, since guidance is occasionally updated.

Filling and treating stored water

If your tap water comes from a public utility that treats it with chlorine, you can generally fill clean containers directly from the tap without adding anything. If your water comes from a private well or another untreated source, it should be disinfected before storage.

The U.S. Environmental Protection Agency publishes guidance for disinfecting water in an emergency. Key points include:

Boiling is the most reliable method for killing disease-causing organisms. Bring clear water to a rolling boil for one minute (three minutes at elevations above about 6,500 feet), let it cool, and store it in clean containers.
Bleach disinfection. Use only regular, unscented liquid chlorine bleach, and check the label for its concentration. The EPA’s guidance lists the number of drops per gallon for common strengths (for example, about 8 drops per gallon for 6 percent bleach). Stir, then wait at least 30 minutes before using. The water should have a slight chlorine smell; if it does not, repeat the dose and wait another 15 minutes.
Cloudy water should be allowed to settle and then filtered through a clean cloth, paper towel or coffee filter before disinfecting. Cloudy water may need a larger bleach dose; follow the official instructions.

Never use scented, color-safe or “splash-less” bleach, and never mix bleach with other cleaning products. Because these instructions are safety-critical, always confirm the exact current figures on the EPA or CDC websites before you treat water.

How long does stored water last?

Water itself does not expire, but stored water can pick up tastes from containers or become contaminated if a seal is imperfect. General guidance is:

Commercial bottled water: observe the expiration or best-by date and keep it sealed until use.
Water you bottle yourself: replace it about every six months.

An easy system is to rotate on a schedule you already remember, such as when the clocks change for daylight saving time. Mark each container with the fill date using a permanent marker or label. Use the old water for plants, cleaning or flushing, then refill.

Where to store your water

Store water somewhere cool and dark. Sunlight encourages algae growth, and heat can cause some plastics to break down faster. Good options include a basement, interior closet, under beds or a pantry shelf.

Keep containers away from gasoline, pesticides, paint and cleaning products. Some plastics are slightly permeable to vapors.
Raise large drums off concrete floors with a wood pallet or board.
Spread your supply across more than one location in the home, in case one area becomes inaccessible.
Keep a few bottles in each vehicle and in your go-bag, rotating them more often because cars get hot.

Hidden water sources already in your home

If you run short, your house probably holds more water than you think. These sources can help in an emergency, with the right precautions:

Water heater tank. A typical tank holds 30 to 80 gallons. Turn off the power or gas first, then drain from the valve at the bottom. The first water out may contain sediment; let it settle.
Household pipes. Open the highest faucet in the house to let air in, then collect water from the lowest faucet.
Ice cubes in the freezer.
Toilet tanks (not the bowl) can provide water for flushing and cleaning. Do not drink it, especially if you use tank cleaning tablets.

If you hear that your local water supply may be contaminated, shut off your home’s main water valve so polluted water does not enter your pipes and water heater.

Going beyond stored water

Stored water covers the short term. For longer disruptions, it helps to have a way to collect and treat more. Options include:

A quality portable filter combined with a disinfection method, since many filters do not remove viruses on their own.
A rain barrel system for garden, cleaning and flushing water, which can be treated for drinking in an emergency with appropriate methods.
Knowing the location of nearby natural water sources and how to purify them.

If you enjoy hands-on projects, 20+ Easy DIY Survival Projects includes a simple water filter, a solar still and a rain catchment system you can build from everyday materials.

A quick checklist

Count people and pets, then multiply by one gallon per day.
Start with three days, then build toward two weeks.
Add extra for heat, children, nursing, illness and cooking.
Use sealed bottled water or clean, food-grade containers.
Label every container with its fill date.
Store in a cool, dark place away from chemicals.
Rotate self-filled water every six months.
Keep unscented bleach and a way to boil water, and bookmark official treatment guidance.

Water is the foundation of every preparedness plan, but it is only the beginning. If you would like to build out the rest of your household plan, from food storage and backup heat to first aid and fire starting, take a look at The Prepper’s Survival Bible, a collection of ten practical PDF guides you can download today and print for your emergency binder.