How Much Water Do You Need?
The standard recommendation is one gallon per person per day — half for drinking, half for cooking and sanitation. For a family of four, that's 28 gallons for a 7-day supply, or 120 gallons for a month.
Minimum storage targets
- 3-day supply: absolute minimum (FEMA recommendation)
- 14-day supply: moderate preparedness
- 30-day supply: serious preparedness
- 90+ days: requires supplemental sourcing (rainwater, wells, filtration)
Storage Containers
Use food-grade containers only — BPA-free HDPE plastic (marked with recycling #2) or stainless steel. Never reuse containers that held chemicals, milk, or juice. Dedicated water storage containers (5-7 gallon jugs or 55-gallon drums) are the safest option.
Water Purification Methods
Stored water should be rotated every 6-12 months if not treated. Alternatively, treat with unscented household bleach (8 drops per gallon for clear water). For sourcing water during emergencies:
- Boiling: 1 minute at rolling boil (3 minutes above 6,500ft)
- Chemical: bleach, iodine tablets, or chlorine dioxide drops
- Filtration: gravity-fed or pump filters rated to 0.2 microns
- UV treatment: SteriPEN or similar for clear water
Rainwater Collection
A 1,000 sq ft roof can capture ~620 gallons from a single inch of rain. Rainwater collection is legal in most states but regulated in some — Colorado, for example, limits collection to two 55-gallon barrels. Check your state's off-grid living regulations.
Location-Specific Water Security
Your water security depends heavily on local rainfall, proximity to freshwater sources, and water table depth. Enter your zip code to see your location's water data — including nearest water bodies, annual precipitation, and drought risk.
Berkey Filters
Gravity-fed water filtration for off-grid and emergency preparedness.
Essential for emergency water security
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