Guide · Water

Making water safe to drink

Water from streams, rivers and rain butts can carry germs you can't see. Treat it before you drink it, even if it looks clear.

Boiling: the most reliable way

1. Let any dirt settle, then pour the clearer water off the top. Strain it through a clean cloth if it's cloudy.
2. Bring it to a rolling boil — big bubbles that keep coming even when you stir.
3. Keep it boiling for at least one minute.
4. Let it cool with a lid on, so nothing falls back in.

Boiling kills germs. It does not remove chemicals or fuel, so avoid water near roads, farms that spray, or anything with an oily sheen.

Purification tablets

Follow the instructions on the pack. Most need 30 minutes before the water is safe; cold or cloudy water may need longer. Keep a strip in your kit — they're light and last for years.

Filters

A camping filter removes most bacteria and parasites. Many do not stop viruses. If the label doesn't say it does, boil or use a tablet as well.

How much you need

Plan for about 3 litres per person per day for drinking and simple cooking — more in hot weather or if you're walking a lot.

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