Guide · Water

Finding water

Water is easier to find if you know how land, plants and animals give it away. Whatever you find, treat it before drinking — clear water can still make you ill.

Read the land

• Go downhill. Water collects in valleys, hollows and low ground.
• Look for green. Lush, bright vegetation, reeds, rushes, willows and similar trees usually mean water at or just below the surface.
• Check dry riverbeds. Dig at the outside of a bend, where water last flowed, or at the lowest point. If the sand or soil gets damp after 30 centimetres or so (about a foot), keep going and let water seep into the hole.
• Look at the base of cliffs and rock faces. Springs and seeps often appear where rock layers meet.
• Check rock hollows after rain. Shaded ones hold water longest.
• On the coast, dig a hole above the high-tide line, behind the first dune. Fresher water can float on top of salt water in the sand. Taste a tiny amount: if it's salty, don't drink it.

Watch wildlife

• Animal tracks that join together and head downhill often lead to water.
• Many birds fly low and direct towards water around dawn and dusk.
• Flies, mosquitoes and bees usually stay fairly close to water.

Plants

• Transpiration bag: tie a clear plastic bag around a leafy branch of a non-poisonous tree or bush in the sun. Tilt it so one corner hangs low. Over several hours, water from the leaves collects in the corner. Expect a small amount — often a cupful or so a day per bag.
• Morning dew on leaves and grass can be wiped up with a cloth and wrung out.
• Avoid drinking plant sap or milky liquids unless you know for certain the plant is safe. Many are poisonous.

Snow and ice

Melt snow and ice before drinking. Eating it lowers your body temperature and uses energy. Ice usually gives more water than the same amount of snow. If melting snow in a pot, start with a little water in the bottom so the pot doesn't scorch. Treat meltwater like any other water.

Water to avoid

• Water with dead animals nearby, or a strong smell or oily sheen.
• Runoff from roads, farms, mines or industrial sites. Boiling doesn't remove chemicals.
• Water with bright green or blue-green scum on it. Algae toxins aren't destroyed by boiling.
• Seawater and urine — they make dehydration worse.

Before you drink

Let dirty water settle, pour off the clearer water, strain it through cloth, then boil it or use purification tablets or a filter. Running water is usually better than still water, and a spring is better than a stream — but treat all of it if you can.

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