Review
When municipal water fails or floodwater contaminates wells, you need a backup purification method.
Method 1: Boiling (Most Reliable)
- Filter cloudy water through cloth or coffee filter
- Bring to a rolling boil for 1 minute (3 min if above 6,500 ft elevation)
- Let cool, store in clean containers
Kills: bacteria, viruses, parasites | Does NOT remove: chemicals, heavy metals
Method 2: Bleach Disinfection
For clear water only:
- 8 drops unscented 6% bleach per gallon
- Stir, wait 30 minutes
- If no slight chlorine smell, repeat 8 drops and wait 15 more minutes
Method 3: Portable Filtration
- LifeStraw Personal — instant drink from bottles/streams; bacteria & parasites
- Sawyer Mini — inline filter for bags and bottles
- Big Berkey — countertop gravity filter for household volume
Method 4: Water Purification Tablets
Iodine or chlorine dioxide tablets work in go-bags. Follow package timing — typically 30–45 minutes.
What NOT to Do
- Don't drink floodwater, pool water, or water with chemical sheen
- Don't rely on filters alone for chemically contaminated sources
- Don't use scented or color-safe bleach
Bottom Line
Boil if you can, filter if you can't, bleach as backup. Keep at least two methods in your kit.
Recommended Products
Frequently Asked Questions
- Does boiling kill all pathogens?
- Boiling for 1 minute (3 minutes above 6,500 ft) kills bacteria, viruses, and parasites. It does not remove chemical contamination.
- How much bleach per gallon?
- Use 8 drops of unscented 6% bleach per gallon of clear water. Stir and wait 30 minutes. Slight chlorine smell means it's safe.
- Which filter removes viruses?
- Most straw filters remove bacteria and parasites only. Purifiers rated to EPA standards or Berkey elements with black filters handle viruses.
Disclaimer: Content is for informational and educational purposes only. In a life-threatening emergency, call 911 (US/Canada) or your local emergency services. PrepareStorm is not a government agency and does not provide emergency dispatch.