Water

Finding, collecting, and purifying drinkable water in the wild.

1. How Much You Need

At rest in mild conditions: about 2 liters per day minimum.

With moderate activity: 3–4 liters.

In hot conditions or at altitude: 4–6 liters.

Don't ration water by drinking less. Ration sweat: reduce movement, stay in shade, work only during cool hours. Your body needs the water you have — sipping tiny amounts doesn't help. Drink when thirsty.

2. Signs of Dehydration

Mild (act now):

• Dark yellow urine
• Thirst, dry mouth
• Slight headache
• Reduced urination

Moderate (urgent):

• No urination for 12+ hours
• Strong headache
• Dizziness when standing
• Rapid heartbeat
• Irritability, difficulty concentrating

Severe (life-threatening):

• No urination
• Confusion, delirium
• Sunken eyes
• Rapid, weak pulse
• Loss of consciousness

3. Finding Water

Best sources (in order of preference):

1. Flowing streams and rivers — moving water is generally safer than still water. Still needs purification.
2. Springs — water emerging from the ground is often the cleanest natural source. Still purify if possible.
3. Rain — collect directly in any container. Safe to drink without purification.
4. Snow and ice — melt before drinking. Never eat snow directly — it lowers your core temperature and costs more heat than it's worth.
5. Dew — tie absorbent cloth around your ankles and walk through grass at dawn. Wring into a container. Surprisingly effective.
6. Lakes and ponds — always purify. Prefer large bodies over small stagnant pools.

How to locate water:

• Go downhill. Water flows to the lowest point. Follow valleys and drainages.
• Listen. Running water can be heard from a surprising distance in quiet wilderness.
• Watch for green patches in otherwise dry terrain — vegetation clusters often indicate subsurface water.
• Follow animal tracks. Game trails that converge often lead to water. Dawn and dusk are when animals drink.
• Watch birds. Grain-eating birds (finches, pigeons) fly toward water in the evening and away in the morning. They fly straight and low when heading to water.
• Insects. Bees are rarely more than 5 km from water. Columns of ants climbing a tree may be heading to a water-filled hollow. Mosquitoes and flies mean water is very close.
• Dig. In dry riverbeds, dig at the outside of a bend, at the lowest point. Water often sits just below the surface. Wait for the hole to fill.

4. Collecting Water

Rain collection:

• Spread a tarp, poncho, or large leaves to funnel rain into a container.
• Tie a cloth around a tree trunk — rain runs down the tree and collects in the cloth. Wring it out.
• Dig a shallow basin and line it with a plastic bag or non-porous material.

Solar still (desert/emergency):

1. Dig a hole about 60 cm deep and 90 cm wide in a sunny spot.
2. Place a container in the center of the hole.
3. Place any green vegetation, wet cloth, or even urine-moistened soil around the container (not in it).
4. Cover the hole tightly with clear plastic. Seal the edges with dirt or rocks.
5. Place a small stone on the plastic directly above the container to create a low point.
6. Moisture evaporates, condenses on the plastic, and drips into the container.

Output: roughly 0.5–1 liter per day. Not enough alone, but supplements other sources.

Transpiration bag:

1. Tie a clear plastic bag around a leafy branch on a living tree (non-poisonous species).
2. Sunlight causes the leaves to release moisture, which condenses in the bag.
3. Weight the bag so water collects at the low corner.
4. Yields roughly 0.2–0.5 liters per bag per day. Use multiple bags.

5. Purifying Water

All surface water should be purified. Even clear mountain streams can contain Giardia, Cryptosporidium, or bacteria that cause severe diarrhea — which accelerates dehydration and can be fatal in a survival situation.

Method 1: Boiling (most reliable)

• Bring water to a rolling boil for 1 minute (3 minutes above 2000m / 6500ft altitude).
• This kills all bacteria, viruses, and parasites.
• If you have no container that can go on a fire, heat rocks in the fire until very hot, then drop them into water in a non-heat-safe container. The rocks will bring the water to a boil.

Method 2: Chemical treatment

• Purification tablets (iodine or chlorine dioxide) — follow the instructions on the packet. Typically 30 minutes wait time.
• Household bleach (unscented, 5–8% sodium hypochlorite) — 2 drops per liter. Stir, wait 30 minutes. Should smell faintly of chlorine. If not, add 2 more drops and wait another 15 minutes.

Method 3: UV light

• UV water purifiers (e.g., SteriPEN) kill microorganisms in 90 seconds.
• In extreme emergency: clear water in a transparent PET bottle placed in direct sunlight for 6+ hours (SODIS method). Less reliable but better than nothing.

Method 4: Filtration

• Commercial filters remove bacteria and parasites. Some remove viruses.
• Improvised filter: cut the bottom off a plastic bottle. Layer (bottom to top): small gravel, sand, crushed charcoal from a fire, more sand, more gravel. Pour water through. This improves clarity and taste but does not make water safe on its own — boil after filtering.

6. What Never to Drink

• Seawater — accelerates dehydration and can cause kidney failure. No amount of rationing makes it safe.
• Urine — increasingly concentrated with waste products. Harmful to drink, especially when already dehydrated.
• Alcohol — diuretic, accelerates dehydration and impairs judgment.
• Blood — high salt content, can carry disease, difficult to digest.
• Water with a chemical sheen, strong smell, or near industrial/mining sites — chemical contamination cannot be removed by boiling.