5 Water Purification Methods Every Family Should Know

Store Water First

You will feel a water shortage before you feel a food shortage. How many days a person can live without drinking is not a number we are going to guess. The planning number that is published is simpler. Ready.gov says to store at least one gallon per person per day for drinking and sanitation, for at least three days. A family of four needs 12 gallons for that minimum. Two weeks, if you have the space, is 56 gallons. That is a lot of jugs, which is why purification matters after the jugs run out.

CDC's emergency water page, updated September 19, 2024, is the reference for making water safer when bottled water and a safe tap are not available.

Method 1: Boiling

Boiling is the method CDC puts first for killing germs.

Bring the water to a rolling boil for 1 minute.
At elevations above 6,500 feet, boil for 3 minutes.
Let it cool.
Pouring it between clean containers improves the flat taste.

Boiling does not remove fuel, heavy metals, or salt. If the water is chemically contaminated, do not boil it and drink it. Let cloudy water settle, and pour off the clearer part before you boil.

Method 2: Household Bleach

If you cannot boil, CDC allows unscented household bleach that contains 5 to 9 percent sodium hypochlorite. Do not use scented bleach, or bleach with cleaners added.

For clear water, CDC's guidance works out to 8 drops, or a little less than 1/8 teaspoon, per gallon. If the water is cloudy, filter it through a clean cloth first, or double the bleach. Stir, and let it stand 30 minutes.

That dose is only for drinking water. A stronger mix you might use to wipe a floor is not a drinking-water recipe. Bleach also loses strength as it ages, so replace the bottle when it gets old. Tablets made for drinking water are easier to carry in a go-bag. Follow the tablet label.

Bleach disinfection is aimed at germs. It is not a fix for chemicals in the water.

Method 3: A Portable Filter

Hollow-fiber filters such as a squeeze filter or a straw-style filter are useful for streams and lakes because they physically block many bacteria and parasites. CDC notes that these filters do not remove viruses. That matters if the water could contain sewage. In that case, boil after filtering, or use a method that addresses viruses.

Read the manufacturer's limit on how much water the filter is rated for, and do not let a ceramic filter freeze. A gravity bag is convenient for a family because it fills a clean container while you do something else.

Method 4: Ultraviolet Light

Battery UV devices can inactivate bacteria, viruses, and parasites in clear water. Cloudy water blocks the light, so filter or settle first. They need power, and they treat one bottle at a time. Use UV as a second step after a filter when you are worried about viruses and cannot boil. If the device fails, you still need another method.

Method 5: Sunlight in a Clear Bottle

Solar disinfection is a low-equipment method used where fuel and filters are scarce. Fill a clear plastic bottle with water that you have already poured through a cloth if it was cloudy, and leave it in direct sun. It is slow, it needs sun, and it is a backup rather than your plan. Do not rely on it for chemically contaminated water.

Use More Than One

Store water for at least three days, and more if you can.
Keep a filter in the go-bag, and remember it does not cover viruses.
Carry purification tablets.
Know the boil time and the bleach dose, and write them down.
Treat sunlight as a last resort.

The supply tracker can compare the water you enter with a daily target. The Prep Roadmap's first phase includes the three-day water task at one gallon per person per day. Neither one purifies a bucket. You still do that part.

Places Water Hides at Home

A water heater holds many gallons. Turn off the power or gas before you drain it, and only use it if you have not had contamination problems with the tank.
The toilet tank (never the bowl) is usable only if you have not put cleaners in it.
Rain off a clean surface can be collected and then boiled.
Water from a stream, pond, or pool needs treatment. Moving water is not automatically safe.

Buy one filter and learn the CDC boil time. That, plus the gallons already in the closet, covers the outage you are most likely to see.