Water Sourcing & Risk

Overview

You can’t operate without water, but unsafe water can incapacitate you. Choose sources with the lowest contamination risk, approach them safely, and assume treatment is required unless you personally control the source. Pair source selection with proper purification from the next chapter.

Skill Level: Basic

Moving vs Stagnant Water

Prefer cold, clear, fast‑moving water emerging from the ground over warm, stagnant pools.

Best: Springs and seep lines near their origin; snowmelt runoffs above human/animal activity.
Better: Mid‑stream flow away from banks; avoid eddies and after recent floods.
Avoid: Stagnant ponds, beaver ponds (giardia risk), stock tanks, or water with visible scum/odor.

📝 Note: Clarity ≠ safety. Microbes and chemicals can be invisible. Always treat.

Surface Clues

Read the water and its surroundings before committing.

Color/odor: Tea‑colored from tannins can be okay; milky/opaque after storms = heavy sediment; chemical or sewage odor = hard no.
Algae: Avoid bright green/blue‑green scums or paint‑like sheens (cyanobacteria toxins are not removed by boiling or most filters).
Animal sign: Tracks and droppings indicate upstream activity—raise treatment rigor.
Upstream check: Walk upstream if time allows; avoid sources downstream of mining, agriculture, industry, or campsites.
Sheen test: Gently swirl surface film with a stick—petroleum sheens tend to swirl and break apart; bacterial sheens often shatter and quickly reform. Avoid either when in doubt.

Urban Sources

Household and building systems can provide emergency water with care.

Water heater tank: 120–300 L typical. Close the main valve first to avoid draining/contamination, then use the drain spigot at the base. Water may be hot—cool before drinking and still treat.
Toilet tank (cistern, not the bowl): Can be clean if no additives (dye/cleaners). Treat before use.
Plumbing: Open highest faucet to admit air; drain from lowest faucet. Sediment may flush initially.
Cisterns/rain barrels: Treat as surface water; elevated organic load demands careful filtration/chemical treatment.

⚠️ Caution: Post‑flood urban water can contain fuel, oil, sewage, or chemicals. Filters may not remove dissolved chemicals or heavy metals. Choose sealed bottled sources when possible.

Approach & Collection Safety

Footing: Wet rocks/logs are slick; use three points of contact; don’t lean into fast water.
Swiftwater: Avoid edges of fast, opaque flows; use poles to probe depth; do not enter moving water above knee depth.
Intake: Collect mid‑column away from banks; avoid disturbing sediments; pre‑filter with cloth to reduce turbidity before treatment.

Snow & ice considerations

Fresh snow is airy and fuel‑intensive to melt; older, compacted snow (firn) yields more water per fuel. Avoid eating snow directly (chills core); melt and warm before drinking.

Distance From Water (Sanitation)

Camp and toilet at least 60–70 m (200–230 ft) from water to prevent contamination and reduce flood risk.
Wash and dispose of dish/soap water away from sources; scatter strainings; use biodegradable soap sparingly.

☑️ Checklist — Source Selection

Clearer, colder, moving water favored over warm/stagnant
No chemical odor or suspicious sheen/scum
Upstream free of obvious ag/industrial/human contamination
Safe approach and footing; avoid fast/opaque edges
Collect mid‑stream/mid‑column; pre‑filter if turbid

Examples

Forest ridge: Spring seep with cool, clear flow—collect above animal trails; filter + chemical.
Desert wash: Cloudy pools after storm—wait to settle, pre‑filter, then filter + chlorine dioxide; consider alternate route to known water cache.
Urban high‑rise: Shut main, drain water heater via spigot; cool and treat; use bottled/packaged water first if available.

Key Takeaways

Choose the cleanest source you can reach safely; assume all natural and building sources require treatment.
Avoid cyanobacteria blooms and any chemical odors—move on if in doubt.
Maintain sanitation distances from water to protect the source and yourself.

Scenarios

🧭 Scenario (Temperate creek post‑storm): Water runs brown.
🔍 Decisions: Scoop now vs wait to settle vs walk upstream.
✅ Outcome: You walk upstream away from camp runoff, collect mid‑stream, and pre‑filter cloth before treatment.
🧠 Lessons: Upstream check + pre‑filter beats muddy filters
🏋️ Drill: Practice mid‑column collection without stirring sediment.

🧭 Scenario (Urban high‑rise): Mains off, you need water.
🔍 Decisions: Heater tank vs toilet tank; close main first?
✅ Outcome: You close the main, drain the water heater, cool and treat.
🧠 Lessons: Building systems = emergency reservoirs
🏋️ Drill: Locate your heater drain and the main shutoff.