Water
You last about three days without it. Sort this before anything else.
How much
- Plan 3 to 4 litres per person per day for drinking and basic cooking.
- Add more for hot weather, pregnancy, illness and pets.
- Washing and flushing need far more. Plan to do less of both.
Storing it
- Sealed shop water is the easy option. Check the date once a year.
- Tap water in clean food-grade containers keeps well. Swap it every six months.
- Keep it cool and dark, away from fuel and chemicals.
- Fill the bath and every pot if you get a warning before an outage.
Making water safe
- Boiling is best: a rolling boil for one minute, three minutes above 2,000 metres.
- Plain unscented household bleach (5 to 9 percent): 2 drops per litre, stir, wait 30 minutes. Double it if the water is cloudy.
- Purification tablets and filters: follow the label exactly.
- Filter cloudy water through a clean cloth first. No method removes chemicals or fuel.
Finding more
- The hot water tank and the toilet cistern (not the bowl) hold clean water.
- Rainwater and streams must always be treated.
- Never drink floodwater, treated or not.
More from official sources
Updated 9 October 2026.