Ops Challenge: Water Hunt – Purify Three Ways

GoBag.One™ | GoBag or Stay Home™

Real emergencies make clean water a moving target. This drill proves you can find it, make it safe, and carry it—without guesswork. We’ll run three methods end-to-end: filter, chemical, and boil. When you can do all three on a clock, in the rain, with cold hands, your GoBag is real.

Key Takeaways

Source → Pre-filter → Purify → Store: The pipeline never changes. Dirty in, safe out, sealed carry.
Redundancy wins: Filters clog, tabs expire, stoves fail. Train all three so one failure doesn’t end the mission.
Measure, don’t guess: Log time-to-clear, tab wait times, and fuel cost per liter. That’s your resupply math.

Main Points

Objective: Collect 3 liters from the best available sources and make them safe using: (1) Filter, (2) Chemical, (3) Boil. You’ll end with three labeled bottles and a short AAR.

Pick Your Sources

Urban: Park spigot, building heater tank, toilet tank (not bowl), decorative fountain intake, rooftop runoff prefilter bucket.
Suburban/Rural: Creek eddies, rain catch off a clean surface, livestock tank (last resort: double treat).

Step 1 — Pre-Filter (All Methods)
Remove the big stuff so your filter lives longer and your boil doesn’t taste like pond. Use a bandana/coffee filter over a cup or cut a DIY prefilter (bottle + cloth + charcoal/sand if you’ve practiced). Let the muddy bottle sit 10–20 minutes to settle; pour off the clearer water from the top.

Step 2 — Purify

Method A: Filter — Use a field filter you’ve actually tested. Backflush before and after. Keep the clean end clean—don’t dip it in the source. If flow rate crashes, you skipped prefiltering or the source is soup. Note how long 1 liter takes.
Method B: Chemical (Tabs or Drops) — Read the label. Typical tabs: 30–35 minutes for bacteria/viruses; up to 4 hours for cryptosporidium with some products. Cold water slows everything. Swirl, wait the full time, then crack the cap and wet the threads for 10 seconds to sanitize the mouth.
Method C: Boil — Bring to a rolling boil (big bubbles) for 1 minute (3 minutes at high elevation). Fuel cost matters; use a lid and windscreen. Let it cool with the lid on to avoid new contamination.

Step 3 — Store & Label
Pour into dedicated clean bottles or bladders. Mark each “Filter,” “Chem,” or “Boil” with time and source. Keep the dirty bottle marked as such so you don’t cross streams later.

Pro Tips

Choose smarter sources: Clear, moving water beats still scum. Collect from just below the surface, away from the bottom sludge.
Keep ends sacred: Anything that touches raw water never touches clean water gear. Color-code caps or use separate bags.
Cold penalty: Chemistry and filters slow down in cold water. Warm the bottle under a jacket before treating if time allows.
Fuel math: Count boils per canister. Write it on the stove case. Boil is king for viruses but expensive on fuel.
Tab rotation: Mark tab pouches with a fat Sharpie date. Old tabs lie to you—replace them yearly.
Backflush discipline: Backflush after silty sources. A minute now saves a filter on the next trip.
Carry plan: One hard bottle for heat and abuse; one soft bladder to expand capacity. Don’t rely on a single container.

Drill Timer (Example)

T+00:00 — Find source, set up prefilter.
T+00:10 — Start Method A (Filter) for 1 liter.
T+00:15 — Start Method B (Tab) on second liter (note required wait time).
T+00:20 — Start Method C (Boil) on third liter (note time-to-rolling boil and fuel used).
T+00:50+ — Label, stow, log times and notes. If chem requires 4 hrs for crypto, set a reminder and finish labeling later.

Safety

Assume surface water is contaminated. Treat every drop. Keep chems away from kids and food. Stoves live outside or in fully ventilated spaces only—no exceptions.

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