Water

Water is the first line on the Be Ready checklist. Be Ready says they are usually over quickly, but longer outages do happen and can be disruptive and distressing. Mains water can also be disrupted during and after a power cut.

How much

Be Ready asks for bottled water for three days, at three litres a person a day for drinking. More would be needed for cooking and washing, and the water outage page says additional water might be needed to make up baby formula, for medical devices and for pets. No official quantity is given for those extras.

The people most at risk in a water outage are those who use more water because of a medical condition, babies and young children, older adults and people with long-term health conditions. Many people in those groups qualify for the Priority Services Register at thepsr.co.uk; see the Priority Services Register. If you or someone in the household relies on a medical device that needs water, Be Ready asks you to agree a plan with your care team now.

If you cannot store bottled water

Bottled water is the safest way to prepare. If there is no space, boiling water or adding purification tablets can make other sources safer to drink in an emergency. Tablets are sold online, at pharmacies and at outdoor and camping shops. They come in different strengths, so follow the label, and most alternative sources need filtering before the tablets are used.

A water butt in an outside area collects water for flushing toilets or watering plants. Do not drink it.

Using the water when the supply is off

Check the water company's website for the position in your area and for any places where alternative supplies can be collected. Customers on the Priority Services Register should have alternative supplies arranged for them; if you believe you are registered and nothing arrives, contact the water company as soon as possible.

While the mains is off, use bottled water only for drinking, washing hands and preparing food. Soft and fizzy drinks kept in a cupboard are also safe to drink. Do not drink milk or fresh juice that smells as though it has gone off. To wash hands, fill a large clean bowl with water and add soap or a household disinfectant. Keeping use to a minimum makes any alternative supply last longer. The checklist also lists hand sanitiser, wet wipes and bathroom products under hygiene.

Babies

Ready-made or ready-to-feed formula is the safest option, because you may not be able to boil water or sterilise bottles. Powdered formula is not sterile and should only be made up with freshly boiled water. Bottled water is not usually recommended for formula, as it is not sterile and may contain too much sodium or sulphate. In rare circumstances, when drinking water is unavailable or contaminated, still bottled water can be used: check the label shows no more than 200 mg per litre of sodium and no more than 250 mg per litre of sulphate, boil it, and let it cool for no more than 30 minutes. The NHS guidance is at https://www.nhs.uk/conditions/baby/breastfeeding-and-bottle-feeding/bottle-feeding/making-up-baby-formula/.

After an outage

Discoloured water is common when the supply returns. Run the cold tap nearest the stopcock, usually under the kitchen sink, until it clears. The stop tap is normally inside where the supply enters the home, or outside near the boundary under a cover. Contact the water company if problems continue. To find your supplier, Water UK keeps a lookup at https://www.water.org.uk/customers/find-your-supplier.