Water Storage and Filtration for Families

The short answer

CDC recommends storing at least one gallon per person per day for three days and trying for two weeks when possible. Store more for heat, illness, pregnancy, and pets. Commercially bottled water is the safest and most reliable emergency source. No household treatment method can make water contaminated with fuel, toxic chemicals, or radioactive material safe.

Start with a household number

Multiply the number of people by one gallon and by the number of days. Four people need a twelve-gallon starting supply for three days. Add water for pets and household members who may need more. Separate drinking and cooking water from a clearly labeled sanitation reserve if storage is limited.

Build in stages: Three days is the minimum starting layer in CDC guidance. Extend toward two weeks as space, lifting ability, container safety, and budget allow.

Choose containers you can manage

Unopened commercial water is the simplest option. For home-filled storage, use food-grade containers with tight covers. Do not reuse containers that held bleach, pesticides, fuel, or other toxic substances. Label each container as drinking water and add the storage date.

CDC advises replacing home-filled water every six months. Store it in a cool place away from sunlight and chemicals. Large containers are efficient but heavy, so combine them with smaller containers that household members can lift and pour without touching the water inside.

The type of advisory determines the response

A boil-water advisory addresses germs and has different instructions from a do-not-drink or do-not-use advisory involving chemicals or other hazards. Follow the exact direction from the water utility and public-health authority. Do not assume a countertop or camping filter is suitable.

Use safe water for drinking, cooking, brushing teeth, making ice, washing dishes, preparing infant formula, and other uses named by local officials.

Know what each treatment method does

Boiling

CDC says boiling is the best way to kill germs. Bring clear water to a rolling boil for one minute, or three minutes above 6,500 feet, then cool and store it in a clean, covered container. Cloudy water should first settle or pass through a clean cloth, paper towel, or coffee filter.

Disinfection

When boiling is not possible, CDC provides instructions for using unscented household chlorine bleach containing 5 to 9 percent sodium hypochlorite. Product strengths and public guidance can change, so keep the current CDC instructions with the supply and follow them exactly.

Filtration

Many portable filters remove parasites but do not remove bacteria or viruses. Filtered water may require additional disinfection. Filters also do not automatically remove fuel, toxic chemicals, or radioactive contaminants.

Choose from the hazard backward

Look for an independently certified claim that names the contaminant or organism you need to reduce. Record cartridge life, flow rate, storage requirements, replacement cost, and whether the device works without power or pressure. A vague “purifies water” claim is not enough.

Named contaminant-reduction claim
Recognized independent certification to the relevant standard
Capacity suitable for the household
Replacement cartridges stored and dated
Instructions available offline
Clean-water container that prevents recontamination

Water plan checklist

Store first. Treat second.

Primary sources

How Tardigrade Supply researches guidance