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Survival Skillset

Lesson 8 of 12

What is upstream? Judging a source

45 min

The beck is perfect. It tumbles clear and cold over mossy stones, high on a fell with no house in sight. You fill your bottle, drink, and walk on. Two hundred metres higher, round a bend you could not see from the pool, a dead sheep lies half in the water.

In this lesson

  • Myth: clear, cold, fast or "self-purifying" water is safe
  • What lives in water and why it matters for treatment
  • Protozoa
  • Bacteria
  • Viruses
  • Chemicals and metals
  • Matching treatment to threat
  • Ranking water sources
  • Common mistakes
  • Walking upstream: judging contamination
  • The method
  • Livestock and wildlife contamination

The rest of this lesson is in the full course

Every module, practical and exam, self-paced and private, with a certificate at the end.

Original price was: £149.00.Current price is: £99.00.

Places on the full course open soon. Module 1 is free to try now.

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