Standard emergency guidelines suggest that you store one gallon of water per day for each person in your household for a three-day to two-week period. Generally, a normally active person needs to drink at least two quarts (½ gallon) of water each day.
Keep in mind that you must consider your family members' needs and habits. You will have to decide the actual amount of water you store for an emergency. Your storage space and individual situation may be such that you should store less or more than the guidelines recommend. Remember, you might adjust your normal habits to get through the emergency period.
1 gallon per person per day
3-day supply x 1 person = 3 gallons
14 days (2-week supply) x 1 person = 14 gallons
(number of days of water needed) x (number of persons in your home) = gallons to store
Select the option that best suits your family.
If your water comes from a public water supplier or is disinfected, you can store it in clean soda bottles or milk jugs with screw-on tops. Follow the directions below.
If your current water source is contaminated or you do not wish to prepare your own water for storage, purchase bottled water from a store. Bottled water is available in local discount stores or grocery stores. Purchase gallon-size (or larger) containers of bottled water. Consult the Bottled Water publication to learn more about how to select a good quality bottled water. Follow step #3 and #4 above once you have purchased the bottled water.
Water from a contaminated source must be disinfected or purified before use. Two methods of purifying water are discussed below. If the contaminated water contains visible particles, let the particles settle to the bottom first, then strain the water through clean cloths or layers of paper towels before disinfecting. The water cannot be disinfected unless particles are removed by filtration first.
Boiling is a good way to purify water. Bring the water to a rolling boil for 1 to 3 minutes. After the water has cooled, fill clean containers as outlined in Method A. (Boiled water will taste better if you put oxygen back in it before drinking. To restore the oxygen, pour the water back and forth between two clean containers several times.)
Regular household liquid bleach contains a compound (5.25% sodium hypochlorite) that will disinfect water. Do not use bleaches that are scented, colorsafe, are marked splashless, or have added cleaners.
Use regular liquid bleach containing 5.25% sodium hypochlorite. Add 16 drops (about ¼ teaspoon) per gallon of water.
The treated water should be mixed thoroughly and allowed to stand for 30 minutes before use. The water should have a slight bleach odor. If it does not, repeat the dosage and let the water stand for an additional 15 minutes before use. Fill clean containers and store as described in Method A.
The guidelines listed in this publication are the simplest options available in most communities.
The following references were used to prepare this publication:
Originally prepared by Cathy Faulcon Bowen, professor, Department of Agricultural Economics, Sociology and Education, and William Sharpe, professor emeritus of forest hydrology. Updated by Jennifer Fetter, Water Resources Extension Educator.
Water is a precious resource, and it becomes even more precious during an emergency. Here's how to store it safely and keep it pure enough to drink.
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When you live in the California mountains, you get used to extended power outages. When you get your water from a well, as we do, those outages shut off the pumps and create shortages.
That’s one reason why we installed a 5,000-gallon water tank on the hill behind our house. It’s always full and gravity feeds the water to outdoor spigots in the garden, assuring us a steady supply.
Although we’ve been through droughts and fires — the 2020 CZU Lightning Fire destroyed 900 homes in our area — it’s the unexpected outages occurring during storms and high winds that create our most frequent water shortages. Luckily, we aren’t in danger of running out, but our situation isn’t typical. Homeowners in towns and cities in the region, and at lower elevations, aren’t as well-prepared.
Water is like air; you don’t realize how much you need it until you don’t have any. As climate conditions become more and more unpredictable, it’s more important than ever to maintain an emergency supply to get you through natural disasters and unforeseen power outages.
Why Store Water for Emergencies?Earthquakes, wildfires, atmospheric rivers … living in California isn’t for the faint-hearted. During the Loma Prieta earthquake that struck our area in 1989, I learned water pipes are among the first things to go during a natural disaster. Even if they don’t, there’s a good chance the water coming from your faucet is contaminated. Here are a few tips for making an earthquake kit.
If you don’t have clean water to drink, you’ll be forced to look elsewhere for it. That may not be possible if power lines are down and the roads impassable.
Storing emergency drinking water is a matter of survival. If you become isolated during a disaster, you’ll also need water for sanitation. It doesn’t have to be 100% percent pure, so you can store it outdoors in large containers, barrels or tanks. Drinking water, on the other hand, must be stored indoors in small, unbreakable containers and easily accessed.
Types of Water You Can StoreThe Centers for Disease Control and Prevention (CDC) recommends bottled water as the safest option for emergency storage.
If the bottles are factory sealed, you can safely drink it without any treatment. If the seal has been broken, however, don’t take any chances. The CDC recommends boiling the water or treating each gallon with four or five drops of unscented liquid household bleach.
It’s also safe to store municipal tap water already treated with chlorine. If you get your water from a well and you drink it straight from the faucet, you can also store that. But you should add four to five drops of unscented bleach per gallon before sealing the container to ensure the water remains pure.
How To Choose Containers for Long-Term Water StorageDon’t store water in any container previously used to store milk, sugary beverages or toxic chemicals. No matter how meticulously you wash these containers, some residue is bound to remain, and even microscopic amounts can contaminate the water.
Containers should be unbreakable, with a narrow neck that lets you pour the water. Water is fairly heavy, so limit the container size to five gallons so it’s easy to lift and handle. For people with limited strength, smaller bottles or a five-gallon container with a spigot near the bottom are ideal.
Store water only in food-grade containers, i.e. plastics numbered 1, 2, 4 and 7. You can find the number within the triangular recycling symbol imprinted on the outside or the bottom of the container. Other types of plastic can leach into the water and contaminate it.
Properly Storing and Rotating Emergency WaterStore your water in a cool, dark room, preferably between 50 and 70 degrees. Leaving the water in the sun to heat up increases the chances of microorganisms growing into colonies. Ultraviolet sunlight also deteriorates the plastic containers.
Label the containers clearly to let everyone know they contain drinking water. The containers should be in a dedicated storage space, not a utility room near toxic substances like gasoline, cleaning chemicals or pesticides.
If you purchase bottles of water and store them in a cool, dark place, the water should stay pure indefinitely. When you fill bottles yourself, however, there’s always a chance of introducing contaminants, so check the bottles every six months or for signs of cloudiness or algae growth. Discard the water if you notice any signs of contamination.
It’s smart to regularly re-fill the containers whether you see contamination or not. There’s no hard-and-fast rule about the rotation period; it can vary from every six months to every five years, depending on the purity of the water and the storage conditions. Use the old water to feed the plants or wash your dishes.
How Much Water Should You Store?You need enough water to supply each person in your household one gallon per day. The CDC recommends storing enough for two weeks, but at a minimum, keep enough to last for three days. If anyone in your household is pregnant or you have pets, don’t forget to store extra water for them.