Water Storage Calculation: How Much Do You Really Need?

You can survive three weeks without food, but only three days without water. In a grid-down scenario, water infrastructure fails quickly. Pumps stop working, pressure drops, and contamination enters the pipes.

The standard advice is "1 gallon per person per day." While this keeps you alive, it is a misery baseline. It accounts for drinking and very light hygiene. It does not account for cooking rice, washing dishes, flushing toilets, or medical needs.

The Realistic Calculation

For a comfortable, sustainable survival situation (Bugging In), aim for 2-3 gallons per person per day.

1. Drinking (0.5 - 1 Gallon)

• Baseline: A sedentary adult needs about 2-3 liters (0.5-0.8 gallons) just for hydration.
• Stress Factors: Heat, physical exertion (chopping wood, carrying gear), and high-sodium storage foods (MREs, canned soup) increase this need significantly.
• Target: Allocate 1 full gallon purely for consumption.

2. Hygiene (0.5 - 1 Gallon)

• Hand Washing: Critical to prevent dysentery and flu.
• Body Wipe: A "sponge bath" uses about 0.5 gallons.
• Teeth Brushing: Minimal, but necessary.

3. Cooking & Cleaning (0.5 - 1 Gallon)

• Rehydrating Food: Freeze-dried meals require boiling water. Rice and beans require lots of water (approx 2 cups water per 1 cup rice).
• Dish Washing: You can't just use a dirty pot. You need water to scrub and rinse.
• Pro Tip: Cook in the pouch or use paper plates to save water on dishes.

The 30-Day Math (Family of 4)

Let's do the math for a standard family of four aiming for a 1-month buffer.

• Survival Minimum: 4 people * 1 gallon * 30 days = 120 Gallons.
• Comfort/Realistic: 4 people * 2.5 gallons * 30 days = 300 Gallons.

What if you run out?

You need a way to scavenge and purify water from rain, rivers, or questionable sources.

Storage Solutions

Where do you put 120-300 gallons of water?

1. WaterBricks / Scepter Cans (Stackable)

• Capacity: 3.5 to 5 gallons each.
• Pros: Portable, stackable, easy to rotate. You can grab them if you have to leave in a vehicle.
• Cons: Expensive per gallon.
• Best For: The first 20-40 gallons (your "Bug Out" water).

2. The 55-Gallon Drum

• Capacity: 55 gallons.
• Pros: Cheap ($20-$50 used food grade), durable.
• Cons: Immovable once full (weighs 460 lbs). Requires a siphon pump to get water out.
• Best For: Garage or basement bulk storage. Two of these equals your "Survival Minimum" for a month.

3. The Bathtub (The "Last Minute" Prep)

• Capacity: 40-60 gallons.
• Tool: WaterBOB (a plastic bladder liner).
• Strategy: If you hear a storm is coming, put the liner in the tub and fill it. This is "bonus" water. Do not rely on an open tub; the drain will leak over time and dust/debris will contaminate it.

Maintenance: The 5-Year Rotation

Water technically doesn't "expire," but it goes stale and can grow algae.

1. Chlorine: Add 1/8 teaspoon of plain, unscented bleach per gallon for 6-month storage.
2. Water Preserver Concentrate: Use a stabilized copper/silver solution for 5-year storage.
3. Rotation: Empty and refill smaller containers every 6-12 months to ensure freshness.

Conclusion

Don't be caught with a single case of Aquafina for a hurricane. Calculate your needs, buy the containers, and fill them this weekend. It is the cheapest, most vital insurance policy you can own.