Emergency Water Storage: How Much You Need and How to Store It

FEMA says 1 gallon per person per day. How to build a reliable supply.

How Much

FEMA recommends storing 1 gallon of water per person per day for at least 3 days. That covers drinking and basic sanitation. For a family of four, the minimum is 12 gallons. However, FEMA also notes that a 2-week supply is preferable, which means 56 gallons for a family of four.

The 1-gallon-per-day figure is a survival minimum. In hot climates, with physical activity, or if anyone is ill, nursing, or pregnant, you may need double that. Children and pets need their own water allocation too. A realistic planning number for comfortable survival is 1.5 gallons per person per day plus 1 quart per pet.

Consider your specific disaster risks. Hurricane zones may need a full 2-week supply because infrastructure recovery takes longer. Earthquake-prone areas should plan for at least 1 week. If you are on a private well with an electric pump, any power outage means zero water, so well households should store more than those on municipal supply.

Containers

Not all containers are safe for long-term water storage. Use only food-grade containers made from HDPE plastic (look for the #2 recycling symbol), glass, or stainless steel. Never reuse milk jugs, juice containers, or any container that held non-food liquids. Milk proteins create bacterial residues that are nearly impossible to fully remove.

The most practical options for home storage are commercially available water storage containers designed for the purpose. Blue 5-gallon jugs with spigots are affordable and stackable. For larger volumes, 55-gallon food-grade barrels work well but require a pump or siphon to dispense and weigh over 450 pounds when full, so place them where they will stay.

Store containers in a cool, dark location away from direct sunlight and chemicals like gasoline, pesticides, or solvents. Plastic can absorb chemical vapors through the walls over time. Garages work if temperatures stay moderate, but avoid spots that freeze or get extremely hot. Sealed commercially bottled water in its original packaging is the easiest option and stays safe indefinitely according to the FDA, though taste may degrade after 1-2 years.

Purification

If you need to purify water from an uncertain source during an emergency, boiling is the most reliable method. Bring water to a rolling boil for at least 1 minute (3 minutes at elevations above 6,500 feet). Boiling kills bacteria, viruses, and parasites. Let it cool before drinking. Boiling does not remove chemical contaminants, heavy metals, or salt.

Chemical disinfection with household bleach is the next best option when boiling is not possible. Use regular, unscented liquid chlorine bleach with 6-8.25% sodium hypochlorite. Add 8 drops (1/8 teaspoon) per gallon of clear water, or 16 drops per gallon of cloudy water. Stir and let stand for 30 minutes. The water should have a slight chlorine smell. If it does not, repeat the dose and wait another 15 minutes.

Portable water filters with a pore size of 0.2 microns or smaller (like the Sawyer Mini or LifeStraw) effectively remove bacteria and protozoa but do not remove viruses. In the US, viruses in freshwater are rare, so these filters are generally adequate for domestic emergency use. For the most complete protection, filter first, then add bleach to catch any viruses the filter missed.

Rotation

Stored tap water should be replaced every 6 months. Even properly stored water can develop a flat taste and the chlorine residual from municipal treatment dissipates over time, reducing its protection against bacterial growth. Mark the fill date on every container with a permanent marker.

Set a calendar reminder for the first day of spring and fall to rotate your supply. The process is simple: pour out the old water (use it for plants, cleaning, or laundry), wash the containers with dish soap, rinse thoroughly, refill with fresh tap water, and re-date the containers. The entire process for a 3-day supply takes about 15 minutes.

Commercially bottled water does not need rotation on the same schedule. The FDA considers commercially bottled water safe indefinitely if the seal is intact and it has been stored properly. However, plastic can leach chemicals over very long periods, especially in heat, so rotating commercially bottled water every 1-2 years is a reasonable practice. Keep a case or two of commercial bottled water alongside your bulk storage as a grab-and-go option.