Guides / water
Water
How much water to store, how to keep it safe, how to make doubtful water drinkable, and what to do when the taps stop.
Reviewed 2026-09-21 · 4 sections · 28 sources
Your region's section opens first once you choose your region. Every region is listed under each section below.
01 How much water to store
Store 1 gallon per person per day, and aim for a 2-week supply for everyone in your home. If you cannot store that much, store as much as you can.[1]
That gallon covers drinking and basic sanitation. Children, people who are sick, and anyone in a hot climate may need more. In very hot temperatures, water needs can double.[2]
Never ration drinking water unless the authorities tell you to. Drink what you need today and look for more tomorrow. Stay cool and rest to reduce how much your body needs.[2]
Count pets, too. A household of four needs four times the per-person amount, before pets.
By region
Northeast / New England
- The standard amount applies. Winter adds a risk: stored water can freeze and split its container, so keep it inside the heated part of the home. General guidance.
- Homes on a private well lose water when the power goes out, because the well pump runs on electricity. Store more, or plan backup power for the pump. General guidance: check your own pump.
Local detail: Southeastern Connecticut
- The standard amount applies: two weeks for each person.[1]
- Homes on private wells, common in the more rural towns, lose water when the power goes out. Store more, or plan power for the well pump. General guidance.
Mid-Atlantic
Southeast & Gulf Coast
- Heat and humidity make water needs higher for much of the year. Plan on the hot-climate amount, 2 gallons per person per day, from late spring to fall.[2]
- Hurricane season runs June 1 to November 30. Have your full supply stored before it starts. After a hurricane, tap water can be unsafe for days.[3][4]
Midwest / Great Lakes
- The standard amount applies for most of the year. During summer heat waves, plan on the hot-climate amount, 2 gallons per person per day.[2]
- Derechos can cause massive power outages that last for days.[5] If your water comes from a well with an electric pump, that means no water. Store the full amount.
Great Plains
- Summer heat on the Plains calls for the hot-climate amount, 2 gallons per person per day.[2]
- Rural homes are often far from stores and on private wells that stop when the power goes out. Store the full supply and then some. General guidance.
Mountain West
- Dry air and altitude increase how much you lose through breathing and sweat, so lean toward more than the minimum. General guidance.
- Remote and mountain communities can be cut off by snow, fire, or road closures. Store at least a 2-week supply[1] and consider more if you are far from town. General guidance.
Desert Southwest
Local detail: Tucson, AZ
- In summer, plan on 2 gallons per person per day[2].
- Pima County reported 123 heat-related deaths by early September 2026, already more than the 117 in all of 2025.[6] Stored water is part of surviving a summer power failure.
- Arizona is taking Tier 1 Colorado River shortage reductions in 2026: a 512,000 acre-foot cut, about 30% of the Central Arizona Project's normal supply.[7] The realistic risks are higher bills and short outages, not dry taps. Stored water covers the outages.
Pacific Northwest
California
Alaska
Hawaii
- Hawaiʻi relies on shipping for most of its food and supplies, so state emergency managers ask households to be 2-Weeks Ready, in case a hurricane or tsunami damages ports and supply chains.[12]
- Warm weather all year means more water. Lean toward the hot-climate amount: 2 gallons per person per day.[2]
02 Storing water safely
- The simplest option: buy commercially bottled water and keep it sealed, in a cool, dark place.[2]
- Filling your own: use food-grade water containers only. Clean them with dish soap, then sanitize them with 1 teaspoon of unscented bleach in a quart of water before filling.[2]
- Replace water you bottled yourself every six months.[2]
- Never reuse containers that held chemicals. General guidance.
- Store a little in several places, so one broken container or one flooded room does not take it all. General guidance.
By region
Northeast / New England
- Keep water where it will not freeze. Freezing can split containers. An interior closet works better than an unheated garage or porch. General guidance.
- Apartments: stack sealed containers under beds and in closets. General guidance.
Mid-Atlantic
- Keep containers off basement floors in flood-prone areas, and out of summer heat in attics or garages. General guidance.
- Flooding is a major hazard here. Store water on a shelf, not the floor.[13]
Southeast & Gulf Coast
Midwest / Great Lakes
Great Plains
- Keep some water in your tornado shelter space: a basement, storm shelter, or small interior room on the lowest level.[14]
- Keep water where it will neither freeze in winter nor cook in summer. General guidance.
Mountain West
- Protect stored water from freezing in unheated spaces. General guidance.
- In wildfire country, keep some water in your car or go-bag, because you may have to leave quickly.[15]
Desert Southwest
- Keep water out of the sun and heat. Store it indoors or in full shade, never in a hot garage or shed, because heat and sunlight break down plastic and encourage algae. General guidance.
- Store it in a cool, dark place, as Ready.gov advises.[2]
Local detail: Tucson, AZ
- For large amounts, food-grade drums or totes work well. Keep them shaded or indoors. General guidance.
- Rainwater: 1 inch of rain on 1,000 square feet of roof yields about 620 gallons, before losses.[16] Tucson Water offers a Rainwater Harvesting Rebate. Check the current terms.[17] Treat harvested water before drinking it.[4]
- A pool or spa is a reserve for flushing and washing, not for drinking unless it is filtered and disinfected. General guidance.
Pacific Northwest
California
- Earthquakes: strap the water heater and keep large water containers low and secured. The water heater is also an emergency reserve.[10]
- Keep water away from summer heat inland. General guidance.
Alaska
- Keep stored water inside the heated part of the home so it does not freeze. General guidance.
- Earthquakes: secure heavy items, including water heaters and water containers.[10]
03 Making water safe to drink
If you are not sure water is safe, do not use it to drink, cook, brush teeth, wash dishes, make ice, or mix baby formula. Use bottled, boiled, or treated water instead.[4]
1. Clear it. If the water is cloudy, filter it through a clean cloth, paper towel, or coffee filter, or let it settle and draw off the clear water.[4]
2. Boil it (best). Boiling is the best way to kill germs. Bring clear water to a rolling boil for 1 minute. At altitude, boil for 3 minutes above 6,500 ft.[4]
3. Or disinfect with bleach. Use plain, unscented household bleach. Check the label for its strength. Add 8 drops of 6% bleach per gallon, or 6 drops of 8.25% bleach per gallon. If the water is cloudy, colored, or very cold, double the bleach. Stir and wait 30 minutes.[19]
Know the limits:
- Bleach does not work as well as boiling against the parasites Cryptosporidium and Giardia.[4]
- Portable filters do not remove viruses. After filtering, disinfect the water too.[4]
- Boiling and bleach cannot remove fuel, toxic chemicals, or radioactive material. If you suspect those, use bottled water and call your health department.[4]
- Never drink water from radiators or boilers in a home heating system.[4]
By region
Northeast / New England
Local detail: Southeastern Connecticut
- Hot-water heating boilers are common in older Connecticut homes. Never drink boiler water.[4]
Mid-Atlantic
Southeast & Gulf Coast
Midwest / Great Lakes
Great Plains
Mountain West
Desert Southwest
- Higher towns, such as Flagstaff, sit well above sea level. Check your elevation, and above the altitude limit boil for 3 minutes above 6,500 ft.[4]
- Stored water in heat loses quality faster. Treat it if it has been kept warm or opened. General guidance.
Local detail: Tucson, AZ
- Treat harvested rainwater before drinking it: boil it, or filter and then disinfect it.[4]
Pacific Northwest
California
Alaska
Hawaii
- After a hurricane or tsunami, follow boil-water notices from your county water department.[4]
- Catchment (rainwater) systems are common in rural Hawaiʻi. Treat catchment water before drinking it. General guidance.
04 When the water stops
- Use the water already in your home. A water heater tank holds a reserve. Shut off its power or gas and the inlet valve first, and let it cool before draining from the bottom valve. General guidance.
- Before a known storm, fill clean containers and bathtubs (bathtub water is for flushing and washing). General guidance.
- Power outages can contaminate water and stop pumps.[21]
- Do not drive or walk into floodwater. 6 inches can knock you down.[22]
By region
Northeast / New England
- Frozen pipes: if the heat is off, take steps so pipes do not freeze.[25] If the heat will be off for days, shut off the main water valve and drain the pipes. Burst pipes can turn a power outage into losing the home. General guidance.
- Well pumps stop in an outage. Know where your main shutoff is. General guidance.
Local detail: Southeastern Connecticut
- Nor'easters and hurricanes knock out power. Fill containers and a bathtub before a big storm arrives. General guidance.
- The Millstone Power Station 10-mile Emergency Planning Zone includes all of Waterford and New London, all of Groton, and part of Montville. If you are told to shelter in place, stay inside with your stored water and listen for instructions.[23]
- Potassium iodide (KI): people who live or work within the 10-mile area can get KI, which may be recommended to help protect the thyroid in a radiological emergency. Take it only when officials say to.[23][24]
Mid-Atlantic
- Flash flooding is common with tropical storms. Never drive through water on a road: 6 inches can knock you down.[22]
- Ice storms can take power down for days, which stops well pumps. Store water ahead. General guidance.
Southeast & Gulf Coast
Midwest / Great Lakes
Great Plains
Mountain West
- Pipes freeze fast in mountain cold. Take precautions before a cold snap.[25]
- During a wildfire, local water systems can lose pressure. Keep your stored supply ready to go. General guidance.
Desert Southwest
- Monsoon flash floods fill dry washes in minutes. Never drive into a flooded wash: 6 inches can knock you down.[22]
- A summer power outage can stop booster pumps in some areas. Ask your water utility whether your area depends on them. General guidance.
Local detail: Tucson, AZ
Pacific Northwest
- After a major earthquake, water may be out for a long time. That is why Oregon asks households to be 2 Weeks Ready.[9]
- Know how to shut off your water main in case pipes break. General guidance.
California
- Public Safety Power Shutoffs: utilities may turn off power to reduce wildfire risk.[28] Homes on wells lose water when that happens. Store water ahead of fire season.
- After an earthquake, check for broken pipes and shut off the main if needed. General guidance.
Alaska
- In extreme cold, frozen water lines are a major risk. Take precautions before a cold snap.[25]
- Rural water systems can take a long time to repair. Store more. General guidance.
Sources for this guide
Numbers in brackets in the text link here. Items marked General guidance are widely accepted practice rather than a figure from one source.
- Food and Water in an Emergency · FEMA · checked 2026-09-21
- Water · Ready.gov (FEMA) · checked 2026-09-21
- Hurricanes · Ready.gov (FEMA) · checked 2026-09-21
- How to Make Water Safe in an Emergency · CDC · checked 2026-09-21
- Facts About Derechos · NOAA Storm Prediction Center · checked 2026-09-21
- Pima County heat-related deaths surpass last year's total · KOLD News 13 · checked 2026-09-21
- Colorado River shortage · Central Arizona Project · checked 2026-09-21
- Extreme Heat · Ready.gov (FEMA) · checked 2026-09-21
- Be 2 Weeks Ready · Oregon Department of Emergency Management · checked 2026-09-21
- Earthquakes · Ready.gov (FEMA) · checked 2026-09-21
- Alaska Division of Homeland Security and Emergency Management (7-Day Emergency Kit) · State of Alaska DHS&EM · checked 2026-09-21
- 2-Weeks Ready in Hawaiʻi · Hawaiʻi Emergency Management Agency · checked 2026-09-21
- Floods · Ready.gov (FEMA) · checked 2026-09-21
- Tornadoes · Ready.gov (FEMA) · checked 2026-09-21
- Wildfires · Ready.gov (FEMA) · checked 2026-09-21
- Our arithmetic: 1 inch × 1,000 sq ft = 83.3 cubic feet × 7.48 gal per cubic foot ≈ 623 gallons (before losses) · Family Survival (calculation) · checked 2026-09-21
- Residential Customer Rebates (rainwater harvesting) · City of Tucson, Tucson Water · checked 2026-09-21
- Tsunamis · Ready.gov (FEMA) · checked 2026-09-21
- Emergency Disinfection of Drinking Water · U.S. EPA · checked 2026-09-21
- Protect Your Home's Water (private wells) · U.S. EPA · checked 2026-09-21
- Power Outages · Ready.gov (FEMA) · checked 2026-09-21
- Turn Around Don't Drown · National Weather Service · checked 2026-09-21
- Millstone Power Station emergency preparedness · Dominion Energy · checked 2026-09-21
- KI (potassium iodide) · Connecticut DEMHS · checked 2026-09-21
- Prepare for Cold Weather · National Weather Service · checked 2026-09-21
- Hurricane Preparedness, Hazards · NOAA National Hurricane Center · checked 2026-09-21
- Monsoon (NWS Tucson) · National Weather Service Tucson · checked 2026-09-21
- Public Safety Power Shutoffs (PSPS) · California Public Utilities Commission · checked 2026-09-21