Guide · Disasters and emergencies

When the tap water stops

Burst mains, droughts, floods and power cuts can all cut off your water. You need water for drinking, cooking and staying clean, so knowing how to stretch what you have matters.

Be ready

Store at least 3 litres of drinking water per person per day for several days. More is better, especially in hot weather.
Keep extra water for washing and flushing.
Know where your stopcock or main valve is.
Have purification tablets, a filter or a way to boil water.

When the water goes off

Check with neighbours or your water supplier to find out how widespread it is and how long it might last.
Turn off your water heater or boiler if it relies on mains water, to avoid damage.
Close the stopcock if there's a burst pipe or flooding.
Listen for instructions from your local authorities. They may set up water stations or issue bottled water.

Find water already in your home

The hot water tank, if you have one, holds clean water. Let it cool and drain it from the tap at the bottom.
Water left in pipes: open the highest tap in the house, then collect from the lowest.
Ice cubes and canned fruit or vegetable juices.
Water in the toilet cistern (not the bowl) is fine for washing and flushing. Don't drink it: cisterns often hold rust, sediment or cleaning blocks.

Never drink water from radiators, hot water heating systems or swimming pools.

Make it last

Drink first. Don't cut back on drinking water to save it.
Use wet wipes or a small bowl for washing instead of running water.
Reuse washing-up and washing water to flush the toilet.
Use disposable plates or wipe plates clean before washing.
Put a bin bag in the toilet if you can't flush at all. See the improvised toilet guide.

Treating other water

Rainwater, streams and other sources should always be treated before drinking. Boil water for at least one minute, or use purification tablets as directed. Clear cloudy water first by letting it settle and straining it through a cloth.

When it comes back

Run the cold tap for a few minutes until the water is clear.
If you've been told to boil water, keep doing so until the authorities say it's safe.
Refill your stored water, ready for next time.

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