Our abundant domestic water supply is generally of little concern. However, situations might occur where the supply of safe water is interrupted due to earthquakes or flooding. Interruptions could be for only short periods of time, or in the case of natural disasters, the supply could be cut off for days. Gunlock, Utah, experienced seven days of isolation without power, cell towers, or water, as the flood of 2005 washed out access to the rest of the county.
Ed Bowler lives in Gunlock and St. George, his son Kip, with his wife Lisa, live in Gunlock. Prior to the flood, Ed had commented to Kip, “What on earth are you doing with four 50-gallon drums of water.” Kip replied, “That’s my wife Lisa’s food storage program.” “Isn’t that a touch of over kill?” Ed Commented. After the seven days of isolation, Ed went to Lisa with “hat in hand,” “I am so grateful you had four 50-gallon drums of water for us to use when we were out of water for seven days.” (Portraits of Loss-Stories of Loss, printed by Paragon Press, SLC).
With the potential of flooding due to high snow pack in many Utah counties, it is recommended that citizens evaluate their emergency water supply in the event that water lines are temporarily washed out.
The Department of Defense, Office of Civil Defense, states that a quart of water or other fluid a day will sustain life, but humans would be much more comfortable, especially in warm weather, with 1 gallon per day. Recommendations for the amount of water to be stored vary from one-half gallon to 1 gallon per day per person, for food preparation and drinking purposes only. An additional one-half to 1 gallon per day is recommended for personal hygiene and dishwashing. Only a short-term supply of water can be stored in most homes. Storing at least a three-day supply is recommended, or up to two weeks if you have adequate storage space.
Many types of containers are available for water storage. Containers should be “food grade,” meaning they were meant to hold food or water. The most commonly used containers are glass, plastic, and metal. The best containers have secure lids and a spout or spigot that allows for dispensing water with minimal or no contamination.
Glass provides a fairly effective container for storage and is non-permeable to vapors and gases. Glass should not be the sole source of water storage since it is easily broken and may be damaged during an emergency event.
Plastic bottles or jugs previously used for beverages make excellent containers. They are lightweight and fairly sturdy. Food-grade plastic containers are sold commercially for water storage and can be purchased at many stores. Non-food-grade plastic containers are not recommended for food storage because harmful chemicals can leach into the food. Very lightweight plastic might split or degrade under storage. Most plastics used in waterbeds or pool liners are not approved food storage plastics.
Stainless steel can successfully be used for water storage. Other metals are not optimal containers unless they are coated and made specifically to hold food or water. Pewter or lead soldered metals should be avoided.
Water containers should be cleaned with warm soapy water and rinsed. Special attention should be given to containers that previously contained food or beverages. Fill container with potable tap water, and then add 1 tablespoon bleach for each 1 gallon of water. Shake well, turning bottle upside down a time or two to sanitize the cap. Let stand for 1 minute, and then pour out the bleach water. Let the container air dry.
One effective way to store water is in clean canning jars. Fill clean mason type quart or half-gallon jars with water, leaving 1 inch of headspace at the top of the jars. Attach two piece metal canning lids. Fill a boiling water canner half full of water and preheat the water to approx. 140 degrees Fahrenheit. Place jars into the water bath. Add more boiling water if necessary so that jars are covered by 1 inch of water. When water returns to a rolling boil, process jars for 20 minutes. Remove jars from the canner and allow them to cool. After seals set, remove screw bands and place jars in storage. Canned water often will have a white mineral precipitate or ring at the water level. This is normal.
Liquid chlorine bleach (unscented) can be used to disinfect water for long-term storage. Use fresh chlorine bleach since it can lose up to half its strength after 6 months. One gallon can be treated by the addition of 1/8 teaspoon of liquid chlorine bleach containing 4 to 6 percent sodium hypochlorite. (Most bleach contains 5.25 percent.) This is equivalent to 8 drops of liquid chlorine bleach. During storage the bleach will break down into oxygen and table salt.
Bottled water can be a quick and convenient way to store water. Although it is convenient, it is not considered to be any safer than water from your tap. Standards for public water supplies are set by the Environmental Protection Agency and those for bottled water are set by the U.S. Food and Drug Administration. Additionally the International Bottled Water Association (IBWA) works with the industry to assure that FDA regulations are followed, assuring a safe, high quality product.
Store water in a clean, dry place off the ground and away from sunlight. Since plastic is permeable to certain vapors, water stored in plastic should not be near gasoline, kerosene, pesticides or similar substances. If you have freezer space, store water in the freezer. It not only acts as water storage but if the electricity goes out it will help keep foods frozen. Leave 2-3 inches of headspace in container to allow for expansion as the water freezes. When potable water (drinkable water) is properly disinfected and stored, it should have an indefinite shelf life. To maintain optimum quality, water should be checked every 6-12 months. Check for secure lids, broken or cracked containers and for cloudiness. Replace the water and treat as before.
In an emergency, if you have not previously stored enough water, you can use the potable water from pipes, your hot water heater, water softener reservoir and ice cubes. Be sure and turn off the heat source first when removing water from a hot water heater. Unless you are advised that the public water supply has been contaminated and is not safe, open the drain valve at the bottom of the water heater and salvage the water stored in the heater and any that may drain back through the pipes. Once water has been drained into clean, sanitized containers, add 8 drops of chlorine bleach per gallon of water, and stir or shake the solution to mix it. Let it set 30 minutes before use. It is advised only to use the water from your toilet tank, waterbed, or swimming pool as a last resort, since these sources may have chemicals present making them non-drinkable. Treat these sources of water as nonpotable. Never use water from the toilet bowl. Other sources of non-potable water are river or lake water. Filter murky or cloudy water through clean cloth or allow the sediment to settle before disinfecting it as described below.
Some emergency situations could occur where the only water available is contaminated by disease-causing organisms. In this case, the same procedures can be used as for treatment of stored water as follows:
Boiling is the most preferred method. This heat treatment requires water to be boiled in a vigorous rolling boil for 5 minutes for any altitude in Utah. Taste may be improved by pouring the boiled water back and forth from one clean container to another several times to incorporate air.
Chemical treatment is less desirable than heat treatment because the effectiveness is dependent on several variables such as: (1) the amount of organic matter in the water, (2) water temperature and (3) the length of time after the chemical is added until it is used. Furthermore, chlorine or water purification tablets will not kill parasite cysts such as Giardia and Cryptosporidium. It is recommended to both filter and chemically treat nonpotable sources of water to minimize potential contamination from bacteria, viruses and parasites.
Clear water can be treated with ¼ teaspoon (16 drops) of liquid chlorine bleach per gallon. Use fresh bleach. Mix the water and allow it to stand for 30 minutes before using. If water is cloudy in appearance, chemical treatment is not recommended. A slight chlorine odor should be detectable in the water. If not, repeat the treatment and let stand an additional 15 minutes before using.
Different types of tablets are available for water purification purposes. Be sure to follow the manufacturer's directions for treatment and allow sufficient time for the chemical to work before using. Check the label for expiration date, since the tablets can become ineffective with time. Most tablets have a storage life of approximately 2–5 years unopened.
You can filter water if you have a commercial or backpack filter that filters to 1 micron. These are available in sporting good stores and are recommended for use when backpacking. They are not recommended to filter large volumes of water or for water with a lot of sediment. Filtering at 1 micron eliminates bacteria, parasites such as Giardia and Cryptosporidium, but it may not eliminate viruses. Therefore, it’s recommended that 5-7 drops (1/8 teaspoon) of chlorine bleach be added per gallon of filtered water. Wait 30 minutes before using the water, or cap the containers and store them in a cool, dry place.
No effective method for decontamination of water that contains radioactive or chemical fallout is available for home use. This decontamination should be supervised by local or state health officers.
Ronda H. Olsen, Family Consumer Science Agent
Carolyn Washburn, Family Consumer Science Agent
Deloy Hendricks, Extension Nutrition and Food Science Specialist
Brian Nummer, Extension Food Safety Specialist
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.