Water Preparedness: Safe Water for Your Household in Any Disruption


The short answer

Water preparedness means your household still has safe water when the tap stops, the water turns unsafe, or the power that runs your pump goes out. The CDC says to store at least 1 gallon of water per person per day for 3 days and to “try to store a 2-week supply if possible,” and, without bottled water, to make other water safe using its separate guidance. Start by working out how much your household needs.

Numbers to know first

  • 1 gallonwater per person per day to store, for drinking and sanitationSource: Ready.gov
  • 3 days / 2 weekssupply for evacuation / supply at homeSource: American Red Cross
  • Can doublewater needs in very hot temperaturesSource: Ready.gov
  • 1 minuterolling boil to make clear water safe from germs (3 minutes above 6,500 feet; EPA says above 5,000 feet)Source: CDC; EPA

Start here

Pick the line that fits where you are now; each page links to the next step.

If you Start with
Have no water stored yet Water Needs, then Storing Water at Home
Need to know how much to store Water Needs
Are under a boil water notice or unsure your water is safe The safety notice below, then Making Water Safe to Drink
Are choosing a water filter Water Filter Ratings and Certifications, then Emergency Water Filters Compared

The water system, layer by layer

Each layer does a different job, and no single product covers all of them. The first three matter for every household.

1. Know how much water you need

Every plan starts with a number: water for drinking and sanitation for each person (Ready.gov), with more for hot weather, pregnancy, nursing, illness, children and pets (Ready.gov; CDC). Without that number you cannot tell whether your supply lasts three days or three weeks. Start here: Water Needs.

2. Store water at home (days to weeks)

Stored water needs a suitable container, a label and a date, a cool place out of direct sunlight, and replacement every 6 months (CDC). Your home also holds water most people forget, such as the water heater tank. Details: Storing Water at Home.

3. Make doubtful water safe

When the water you have may carry germs, you need a way to treat it: boiling, chemical disinfection, filtering or ultraviolet light. Each one handles different problems. Boiling and disinfecting cannot make water with fuel or toxic chemicals safe (CDC); if you suspect those, use a different water source. Details: Making Water Safe to Drink.

4. Choose filters on evidence, not marketing

The difference between a filter and a purifier, and what a certification covers, is explained in Water Filter Ratings and Certifications. The makers’ claims and certification listings for named products are compared in Emergency Water Filters Compared.

5. Your own source (in progress)

Private wells, springs, rainwater and surface water each come with their own tests and rules. Private wells come first in this section, because they are where GoldBlock’s field experience is deepest: one GoldBlock co-founder works in the water-well drilling trade under a licensed operator, on residential and agricultural water systems. That is field experience, not a license. Owners of private wells are responsible for testing and treating their own water; the CDC’s page on well water safety explains why.

6. When the city, the grid or the weather fails (in progress)

Pages on boil water notices, wildfires, earthquakes, frozen pipes and long power outages are planned to follow the first layers above.

Mistakes that sink most water plans

Each of these runs against a published source.

  • Storing too little. The planning figure is per person and per day: at least 1 gallon per person per day for 3 days, and a 2-week supply if possible (CDC), with needs that “can double” in very hot temperatures (Ready.gov).
  • Trusting a box instead of a test. Words like “purifies” and “removes 99.9%” mean little without a published standard behind them. The CDC notes that EPA does not independently test the “purifier” claims makers put on labels (CDC Yellow Book).
  • Forgetting the pump. If your water comes from a private well, “an electric water pump draws groundwater from the well”; in a power outage the system loses pressure as faucets are opened, and once “no water comes out of the faucets” the supply has stopped until power returns (Chester County Health Department, Pennsylvania: Well Water and Power Outages, read October 19, 2026).
  • Never rotating. Water you filled yourself should be replaced every six months (CDC).

Common questions

How much water should I store?

At least one gallon per person per day, for drinking and sanitation. Plan for at least 3 days, and 2 weeks at home if you can (CDC and the American Red Cross). Store more for hot weather, pregnancy, nursing, illness, children and pets. See Water Needs.

Is bottled water enough for an emergency?

Unopened, commercially bottled water is, in the CDC’s words, “the safest and most reliable source of water in an emergency.” The limit is how much you have. The CDC’s emergency guidance covers what to do when stored water runs out: boil, disinfect or filter other water.

What is the difference between a water filter and a water purifier?

A filter physically removes particles and some germs; most portable filters do not remove viruses. A purifier claim means the maker’s own testing showed it reduces bacteria, viruses and protozoan cysts to a set level. See Water Filter Ratings and Certifications.

Should I ration water in an emergency?

No. Ready.gov advises: “Never ration drinking water unless ordered to do so by authorities.” It adds: “Drink the amount you need today and try to find more for tomorrow.”

Go deeper

Connected systems

Sources

  • Ready.gov: Water (U.S. Department of Homeland Security, FEMA; read October 19, 2026). At least one gallon per person per day for several days, for drinking and sanitation; water needs can double in very hot temperatures; never ration drinking water unless ordered to by authorities.
  • American Red Cross: Survival Kit Supplies. Water: “one gallon per person, per day”; “3-day supply for evacuation”; “2-week supply for home.” Read October 19, 2026.
  • CDC: How to Create an Emergency Water Supply (U.S. Centers for Disease Control and Prevention; reviewed June 27, 2025; read October 19, 2026). At least 1 gallon per person per day for 3 days, a 2-week supply if possible; unopened commercially bottled water is the safest source; replace self-filled water every 6 months.
  • CDC: How to Make Water Safe in an Emergency (reviewed September 19, 2024; read October 19, 2026). Rolling boil for 1 minute, 3 minutes above 6,500 feet; water with fuel, toxic chemicals or radioactive materials cannot be made safe by boiling or disinfecting.
  • EPA: Emergency Disinfection of Drinking Water (U.S. Environmental Protection Agency, last updated February 24, 2026; read October 19, 2026). Rolling boil for at least 1 minute, 3 minutes above 5,000 feet.
  • CDC: Drinking Water Advisories: An Overview (reviewed March 4, 2024; read October 19, 2026). Definitions of boil water, do not drink and do not use advisories.
  • CDC: Prepare and Store Powdered Infant Formula in an Emergency (reviewed August 10, 2026; read October 19, 2026). Ready-to-feed formula is the safest option; use bottled water for powdered formula until officials say tap water is safe.
  • CDC Yellow Book 2026: Water Disinfection for Travelers (Backer and Hill; read October 19, 2026). Makers “must conduct their own testing”; “The EPA does not independently test the validity of these claims.”
  • CDC: Well Water Safety (reviewed June 4, 2024; read October 19, 2026). Tap water from private wells is not regulated, treated or monitored by officials; owners are responsible for making sure it is safe to drink.
  • Chester County Health Department (Pennsylvania): Well Water and Power Outages (read October 19, 2026). An electric pump draws the water; the system loses pressure during an outage as faucets are opened.