When the water goes off

If your taps have just stopped, here's what the official guidance says, what your water company has to provide, and when compensation is due.

The taps have stopped

Just your home, or the whole street?Water UK's guidance suggests checking the cold tap in the kitchen, the inside stop valve (stopcock) and whether neighbours have water. If the kitchen tap works but nothing else does, it says the problem is likely to be in the home's own plumbing.
On a pump? A private well or borehole pump, or a building's booster pump, runs on electricity, so the taps stop when the power does. Power cuts are reported on 105 (Northern Ireland: 03457 643643). What else stops in a power cut.
News and where to get water. The government's Be Ready guidance calls your water company the best source of information. In Scotland that's Scottish Water; in Northern Ireland, NI Water.
Drinking water. The same guidance suggests keeping bottled water for drinking, washing hands and preparing food while the mains is off.
Notices. Your water company may issue a boil-water, "do not drink" or "do not use" notice. Each means something different (see below).
Extra help. Be Ready suggests that anyone eligible joins their water company's Priority Services Register.

Flushing the toilet

South West Water's guidance, where the drains are working, is to flush by pouring water from a water butt straight into the bowl, and not to flush wipes, even "biodegradable" ones. Rainwater from a butt is for the garden and the toilet, not for drinking.

Where toilets can't be used, for example when a septic tank has flooded, UKHSA lists temporary toilets and purpose-made waste bags as the alternatives. Your water company or council gives local instructions for the waste.

Is the hot water tank a reserve?

Not for drinking or cooking: water from the hot tap isn't drinking water. Whether you can draw any water from the tank in an outage depends on how your home is plumbed. Some systems (unvented cylinders) feed the taps at mains pressure, so when the mains stops, the hot taps may stop too. A plumber can say what a particular system allows.

The three kinds of notice

Boil water: germs may have got into the supply. The Drinking Water Inspectorate's guidance is to boil tap water before drinking it, cleaning teeth, making ice, preparing food, cleaning feeding equipment, or giving it to pets.
Do not drink: the tap water isn't for drinking, even boiled: UKHSA notes that boiling doesn't remove chemicals. Your company provides bottled or tanker water and says what else the tap water can be used for.
Do not use: the tap water isn't for any use until your company says so.

What your water company will do

In England and Wales, Ofwat's rules say a water company must provide alternative water, at least 10 litres per person per day, within the first 24 hours of a supply failure, and keep doing so until the taps are back. That's usually bottled water from a collection point (a "bottled water station"), or a tanker or standpipe in the street. It isn't usually delivered to every door.

Water companies keep a Priority Services Register for households that need extra help; your company's website says who can join. People on it can get bottled water brought to them. Thames Water says registering during an incident won't mean help arrives straight away. In Northern Ireland it's called the Customer Care Register.

For anyone who uses medical equipment that needs water, Be Ready suggests making an outage plan with their care team.

Compensation

If your water is off for longer than the rules allow, you may be owed money. The amounts depend on where you live and on your water company, and there are exceptions.

England and Wales: a planned cut of more than four hours needs at least 48 hours' written notice. In an emergency, the supply should usually be back within 12 hours of the company knowing (48 hours for a burst on a major main).
Water companies whose area is wholly or mainly in England: if it isn't, £50, then £50 for each further 12 hours, with a cap; see Ofwat. Which scheme applies depends on where your water company's area is, not on where your home is.
Companies in Wales have different minimum payments (Ofwat's published minimum is £20, then £10 for each further 24 hours, and Welsh Water's own promise is higher). Each company publishes its scheme.
Scotland: Scottish Water's scheme pays £30 for the first 12 hours of an unplanned cut, then £15 for each further 12 hours, up to £90. You have to claim it.
Northern Ireland: NI Water publishes its own service promises, including alternative supplies when a cut is expected to last more than 24 hours. NI Water can say what payment applies.

Sources: Ofwat, Welsh Water, Scottish Water. In England, if a payment you're owed doesn't arrive, you can normally claim it within three months.

When the water comes back

Be Ready says it's common for water to come out discoloured at first, and suggests running the cold tap nearest the stop valve until it clears.

Guides

Storing water for an emergencyHow much to keep for your household, what to keep it in, and how long it lasts.
Water containers: with a tap, or collapsibleWhich say they're safe for drinking water, and what testers found.
Water buttsSizes, diverters, winter care and what a butt really saves.
Water filters and purification tabletsWhat each one removes, and how they compare with boiling.

Water is part of the 72-hour kit, alongside light, food, warmth and a radio.