How much water do you need in a crisis? Litres per person for one week

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DSB recommends storing about 20 litres of drinking water per person. That lasts for a week. A family of four therefore needs about 80 litres – for example six 15-litre jugs, filled from the tap.

For comparison, a Norwegian household uses on average 180 litres of water per person every single day, according to the City of Oslo. The 20 litres are a minimum for drinking, simple cooking and basic hygiene. Here's the table for your household, and how to store the water properly.

Last updated 30 September 2026 · Hurtig Beredskap

In short

About 20 litres of drinking water per person covers the minimum need for one week (DSB).
The advice used to be 9 litres per person for three days. In 2024 the recommendation was extended to one week.
Fill clean jugs with cold water straight from the tap, and fill them all the way up.
Store the water somewhere dark and cool. Clean water in clean containers keeps for years, but you may want to change it once a year for the taste.
If you get a boil-water notice, the water must boil vigorously for a few seconds. Freezing does not kill bacteria.

How much water do you need per person?

DSB (the Norwegian Directorate for Civil Protection) puts it like this: “We recommend storing about 20 litres of drinking water per person. That lasts for a week.” In the brochure “Advice on emergency preparedness” (in Norwegian), DSB calls this the minimum need. The water should cover drinking, cooking and hygiene, and some of your fluid intake can come from juice, soft drinks and other non-alcoholic drinks.

Before 2024 the advice was to cope for three days, with 9 litres per person. Now the authorities recommend that as many people as possible can cope on their own for one week. Many articles online still use the old figure.

More and more people follow the advice. In DSB's survey from December 2025, 54 per cent said they had stored drinking water – twice as many as in 2019.

Table: how much water your household needs

People in the household	Water for one week	15-litre jugs	Capacity
1	about 20 litres	2	30 litres
2	about 40 litres	3	45 litres
3	about 60 litres	4	60 litres
4	about 80 litres	6	90 litres
5	about 100 litres	7	105 litres

The table is based on DSB's figures and rounded up to whole jugs. If you have pets, they need water too – DSB lists “food and water for pets” on its checklist, but gives no figure in litres.

Why might the water disappear?

Norwegian waterworks generally supply safe water – the Norwegian Food Safety Authority reports that about 99.7 per cent of the population receives water of satisfactory quality. But tap water depends on power, pipes and clean sources. DSB notes that a power cut can mean that tap water and sewage stop working normally.

Power cuts. New and renovated homes often have automatic water shut-off valves. Kragerø municipality points out that such homes can also lose water when the power goes.
Burst mains. Water main breaks happen regularly and can cut off the water for hours or days.
Contamination. In Askøy in 2019, drinking water from a reservoir was contaminated. According to the Norwegian Institute of Public Health, just under half of the people supplied from it fell ill.
A single source. About 90 per cent of Oslo's drinking water comes from Maridalsvannet, and the city currently has no backup source.

How to store tap water

Use clean containers made for food and drink. Look for the glass-and-fork symbol. Jugs, bottles and jars all work.
Wash the jugs. DSB recommends rinsing with water mixed with two capfuls of household chlorine bleach per 10 litres, leaving it for at least 30 minutes and then rinsing well.
Run the tap until the water is cold. That way you store “fresh” water. Hot water can release metals from the pipes.
Fill to the top. The less air, the better the water keeps.
Store dark and cool. Sunlight and heat can break down the plastic and cause algae growth. Don't store the water next to petrol, paint or other chemicals.
Think about frost. Water that freezes can split a full jug. If you want to freeze water, don't fill the container completely.

Several small jugs are often easier to find room for than one big one – especially in a flat. See also how to fit your emergency supplies into a flat (in Norwegian).

How long does water keep in a jug?

A long time. DSB says clean water in clean containers can be stored for years without becoming dangerous to drink. A slightly odd taste or smell doesn't matter for your health.

For the taste, DSB recommends changing the water once a year. A handy tip from Bergen municipality: change the water on the day you hang up your Advent star. Bottled water has a best-before date, but that's mainly about the producer guaranteeing the contents.

If the water is contaminated: boil-water notices

If your municipality issues a boil-water notice, follow the advice of the Norwegian Institute of Public Health (FHI): bring the water to a rolling boil for a few seconds. You can use a saucepan, kettle or microwave.

Use boiled water for	Unboiled water is fine for
Drinking, squash and baby porridge	Cooking food
The coffee machine (it doesn't boil the water)	Washing hands
Brushing teeth and ice cubes	Showering – but avoid swallowing water
Rinsing fruit and vegetables	Laundry and cleaning
Washing up by hand	The dishwasher on its hottest and longest programme

Cold doesn't help: freezing and fridge temperatures do not kill microorganisms. FHI also notes that you can use the water in your emergency supply instead.

Water from the hot-water tank can be drained in an emergency, but shouldn't be drunk. If you suspect the water could be contaminated by something that boiling won't remove, such as chemicals, don't drink it.

Water in our kits

All our emergency kits include collapsible 15-litre jugs that you fill from the tap:

Mini: 2 jugs, 30 litres. Enough for one person.
Standard: 2 jugs, 30 litres. Two people need about 40 litres, so add one jug or a few bottles.
Large: 3 jugs, 45 litres. Enough for two people.

If there are more of you, add jugs yourself. They're cheap, and the table above shows how many.

Frequently asked questions about emergency water

How much water should I store per person?

About 20 litres per person for one week, according to DSB.

How much water does a family of four need?

About 80 litres. That's six 15-litre jugs.

How often should I change the water?

DSB recommends once a year, for the taste. Clean water in clean containers doesn't become dangerous from standing.

Can I drink water that has been stored for a long time?

Yes, if it has been stored clean, dark and cool. A slightly odd taste or smell doesn't matter for your health, according to DSB.

What do I do if the water is gone for more than a week?

Your municipality may set up emergency water points where residents can collect water. Keep an eye on the municipality's website and listen to NRK P1 to find out where and when.