Short answer. When the tap runs dry, protect what is already in the house. If officials report broken water or sewage lines, close your main valve so contaminated water cannot enter your pipes 12. Your pipes, water heater tank and ice cubes still hold usable water 12. Keep bottled water for drinking, hand washing and food 4. The UK advises 3 litres per person per day for 3 days 4.
What should I do in the first hour?
- Is it only my home? In cold weather, a tap that gives only a trickle points to a frozen pipe 7. Check your water supplier's website for service in your area; UK guidance names the water company as the best source of information 4.
- Is the water unsafe, not just absent? Listen to local officials for advice on water precautions in your home 1. If you need to treat water, the Phaenyx guide on making water safe to drink covers boiling and bleach.
- Should I close the main valve? The CDC says you may need to shut it off to keep contaminants out of your pipes 1. The Red Cross gives the same step when there are reports of broken water or sewage lines, and asks every family member to learn it beforehand 2.
- Who in the house needs more water? UK guidance says extra water may be needed for baby formula, medical devices and pets, and asks anyone who relies on a medical device that needs water to plan with their care team 4.
What should the first litres go to?
Drinking comes first. Ready.gov says never to ration drinking water unless authorities order it: drink what you need today and look for more for tomorrow 3. In the UK, the government asks you to use bottled or other alternative water only for drinking, washing your hands and preparing food 4.
For infant formula, UK guidance says ready-to-feed formula is the safest option and bottled water is not usually recommended for making up feeds 4. If bottled water must be used, it should contain no more than 200 mg/L of sodium and 250 mg/L of sulphate, be boiled and cooled for no more than 30 minutes 4. Ask a midwife or doctor about your own baby.
How much water a household needs over several days is covered in the guide on water per person.
Where is the hidden water in my home?
The CDC and the Red Cross both list water already in the house.
| Source | CDC | American Red Cross |
|---|---|---|
| Water heater tank (the tank feeding taps and showers) | Yes 1 | Yes 2 |
| Water left in the pipes | Not listed 1 | Yes 2 |
| Ice cubes made from clean water | Yes 1 | Yes 2 |
| Liquid from canned fruit and vegetables | Yes 1 | Not listed 2 |
| Toilet tank (never the bowl) | Only if clear and free of cleaning chemicals 1 | No 2 |
| Swimming pool or spa | Hygiene and cleaning only, not drinking 1 | No 2 |
| Radiators, home heating system tank, waterbeds | No: use the tap water heater, not the heating system tank 1 | No 2 |
The agencies disagree on the toilet tank. The CDC accepts tank water that is clear and has not been chemically treated 1; the Red Cross says not to use flush tanks at all 2. The CDC excludes tank water treated with toilet cleaners, such as those that change the colour of the water 1.
Water in the pipes. The Red Cross method: turn on the faucet at the highest level of the home to let air in; a small amount will trickle out. Then collect water from the lowest faucet 2.
Water heater. The Red Cross method: make sure the electricity or gas to the tank is off, open the drain at the bottom, close the water intake valve at the tank and turn on a hot-water faucet to start the flow 2. Refill the tank before turning the power or gas back on; if the gas was shut off, a professional will be needed to turn it back on 2.
Water from outside the home (rain, streams, ponds) must be treated before drinking 1. UK guidance says not to drink rain-butt water, which may carry bacteria, but it can flush toilets 4. Never use water contaminated by fuel or toxic chemicals; no home treatment makes it safe 1.
How do I use the toilet without running water?
Keep drinking water out of the toilet: UK guidance says rain-butt water, which should not be drunk, can be used for flushing toilets 4. The Phaenyx guide on emergency sanitation covers the two-bucket method, bags, hand hygiene and safe disposal.
What if my pipes froze?
The Red Cross says to suspect a frozen pipe if only a trickle comes out of a faucet, especially pipes along exterior walls or where the water service enters through the foundation 7. Keep the faucet open, then warm the pipe with a hair dryer, a portable space heater kept away from flammable materials, or towels soaked in hot water 7. Do not use a blowtorch, kerosene or propane heater, charcoal stove or any open flame 7. Apply heat until full water pressure returns, check the other faucets, and call a licensed plumber if you cannot find, reach or thaw the frozen section 7.
What happens when the water comes back?
Discoloured water is common after an outage. UK guidance says to run the cold tap nearest your stopcock, usually under the kitchen sink 4. Milky white water is usually tiny air bubbles: pour a glass and, if it clears from the bottom up, it is air, which is not harmful to health and should normally clear within 24 hours 5. Contact your water supplier if it stays cloudy for more than a day or has an unusual taste or smell 5.
If you drained the water heater, refill it before switching it back on 2.
Where do authorities hand out water?
In England, Citizens Advice says that if an emergency interruption, such as a burst main, lasts more than 12 hours, the water company should provide an alternative supply such as bottled water or bowsers 6. People on their water company's Priority Services Register have alternative supplies arranged for them 4. Register before you need it if someone in your home is eligible 4. Elsewhere, listen to reports from local officials 1.
What official agencies recommend
- United States (CDC): Use the water heater tank, clean ice and canned liquids; toilet tank water only if clear and untreated; pools for hygiene only; shut the main valve if needed; treat all outdoor water 1.
- United States (Ready.gov): Do not ration drinking water unless officials order it; store at least one gallon per person per day for several days 3.
- American Red Cross: Hot-water tank, pipes and ice are safe; no toilet tanks, radiators, waterbeds or pools; know how to close the main valve 2. Thaw frozen pipes without open flame 7.
- United Kingdom (UK Government, DWI): Keep 3 litres of drinking water per person per day for 3 days; reserve it for drinking, hand washing and food; join the Priority Services Register if eligible 4. Cloudy water after a repair is usually air and should clear within 24 hours 5.
The main disagreement is the toilet tank 12, and amounts differ: one US gallon (about 3.8 litres) 3 against 3 litres in the UK 4. Follow the agency of the country you live in.
Frequently asked questions
Can I drink the water from my water heater?
The CDC and the Red Cross both list the tap water heater tank as a usable source 12. Turn off its power or gas first and refill it before switching it back on 2.
Is cloudy water safe after the supply comes back?
Usually. The DWI says cloudiness that clears from the bottom of a glass upwards is air and is not harmful to health 5. If it lasts more than 24 hours or tastes or smells odd, call your supplier 5.
Should I ration my drinking water?
No, unless authorities order it. Ready.gov says to drink what you need today and find more for tomorrow 3.
How long before my water company should provide bottled water?
In England, Citizens Advice says an alternative supply should be provided once an emergency interruption passes 12 hours 6. Citizens Advice has separate advice for Scotland, Wales and Northern Ireland 6.
Water and air where you live
Phaenyx lists water risks country by country.
Your Phaenyx plan includes a "Water and air" section that sets out the water and air risks for your postal code. Build your Phaenyx plan.
Sources
- Centers for Disease Control and Prevention (CDC) — How to Find Clean Water in an Emergency — https://www.cdc.gov/water-emergency/about/how-to-find-clean-water-in-an-emergency.html (accessed 2026-10-27)
- American Red Cross — Food and Water in an Emergency — https://www.redcross.org/content/dam/redcross/atg/PDF_s/Preparedness___Disaster_Recovery/Disaster_Preparedness/Food_Safety/Food_and_Water-English.revised_7-09.pdf (accessed 2026-10-27)
- Ready.gov (U.S. Department of Homeland Security / FEMA) — Water — https://www.ready.gov/water (accessed 2026-10-27)
- UK Government (Be Ready campaign) — Water supply interruptions or outages — https://beready.campaign.gov.uk/be-informed-about-hazards/water-supply-interruptions-or-outages (accessed 2026-10-27)
- Drinking Water Inspectorate (DWI) — White or Cloudy Water — https://www.dwi.gov.uk/consumers/learn-more-about-your-water/white-or-cloudy-water/ (accessed 2026-10-27)
- Citizens Advice — Interruptions to your water supply — https://www.citizensadvice.org.uk/consumer/water/water-supply/interruptions-to-your-water-supply/ (accessed 2026-10-27)
- American Red Cross — Preventing & Thawing Frozen Pipes — https://www.redcross.org/get-help/how-to-prepare-for-emergencies/types-of-emergencies/winter-storm/frozen-pipes.html (accessed 2026-10-27)
Turn this into action
A plan worked out for your household.
- Water, food and equipment counted for each person and pet
- The nuclear plants and zones around your home
- Phaenyx Safe: one tap to tell your people you are safe
Sources
- Centers for Disease Control and Prevention (CDC) · How to Find Clean Water in an Emergency checked 2026-10-27
- American Red Cross · Food and Water in an Emergency checked 2026-10-27
- Ready.gov (U.S. Department of Homeland Security / FEMA) · Water checked 2026-10-27
- UK Government (Be Ready campaign) · Water supply interruptions or outages checked 2026-10-27
- Drinking Water Inspectorate (DWI, England and Wales) · White or Cloudy Water checked 2026-10-27
- Citizens Advice (UK) · Interruptions to your water supply checked 2026-10-27
- American Red Cross · Preventing & Thawing Frozen Pipes checked 2026-10-27