How Much Water Does Your Family Need?
The standard guideline is 1 gallon per person (and per pet) per day. This is divided as:
- ¾ gallon — drinking and food preparation
- ¼ gallon — sanitation and basic hygiene
Four Levels of Water Storage
Level 1 — 3-Day Supply
Minimum: 7+ gallons per person. This covers the FEMA-recommended 72-hour emergency window — the first and most critical milestone for every household.
Level 2 — 3-Week Supply
Target: 21+ gallons per person. Sufficient for most regional disruptions — severe storms, infrastructure failures, or extended quarantine situations.
Level 3 — 3-Month Supply
Target: 122+ gallons per person. At this level you should also know how to purify additional water sources, as rotation and supplementation become important.
Level 4 — Extended Supply
Store as much as space and budget allow. Develop ongoing water collection capabilities — rainwater harvesting, a private well, or proximity to a clean water source.
Quick Reference Table
| Level | Duration | Per Person | Family of 4 | Family of 6 |
|---|---|---|---|---|
| Level 1 | 3 days | 7 gal | 28 gal | 42 gal |
| Level 2 | 3 weeks | 21 gal | 84 gal | 126 gal |
| Level 3 | 3 months | 122 gal | 488 gal | 732 gal |
Choosing the Right Containers
✅ Approved Containers
- PETE (PET) plastic containers — look for recycling symbol #1. Clean, opaque, food-grade. Excellent for smaller volumes.
- Heavy-duty food-grade plastic barrels or drums — ideal for large-volume household storage (up to 55 gallons).
- Commercial water storage containers designed specifically for emergency water storage.
❌ Containers to Avoid
- Milk jugs (HDPE, #2) — difficult to clean thoroughly; trace dairy protein residue can support bacterial contamination over time.
- Non-food-grade plastic containers of any kind.
- Cardboard containers or thin-walled plastics not designed for liquid.
- Containers that previously held non-food products.
Treating Water Before Storage
- Municipal (tap) water: Already treated with chlorine — no additional pre-treatment is needed. Simply fill clean containers and seal them.
- Non-chlorinated water (private well, spring, river, etc.): Add 8 drops of unscented liquid household bleach (5–8% sodium hypochlorite) per gallon before sealing.
Rainwater Harvesting
Rainwater collection is an excellent supplement to stored water. Regulations vary by state — in Utah as an example:
- Residents may collect rainwater in up to two 100-gallon containers without a permit.
- With a permit, collection of up to 2,500 gallons is allowed.
Always check your local and state regulations before setting up collection systems. Collected rainwater should be filtered and treated before drinking; it is generally safe for sanitation and garden irrigation without treatment.
Water Purification Methods
If stored water runs low, knowing how to purify water from alternative sources can be life-saving. Here are the three most practical methods:
Boiling
The most reliable and universally effective method. Bring water to a vigorous rolling boil for at least 5 minutes (add 1 minute per 1,000 feet of elevation above sea level). Kills bacteria, viruses, and parasites including Giardia and Cryptosporidium.
Chemical Treatment
Use iodine tablets or unscented household bleach. For clear water, add 8 drops of bleach per gallon; for cloudy water, use 16 drops. Stir, then let stand 30 minutes before drinking.
Distillation
Boil water and collect the condensed steam. This process removes heavy metals, salts, and most biological contaminants. Best for highly contaminated water where other methods may be insufficient.
Emergency Water Sources in Your Home
If stored water runs out, these household sources may be available:
- Hot water heater tank — typically holds 30–60 gallons of clean, potable water. Turn off the heat source first, then open the drain valve at the bottom.
- Ice cubes — allow to melt and use for drinking.
- Toilet tank (not the bowl) — the water in the tank is clean and potable, unless chemical tablet disinfectants have been added to the tank.
- Canned goods liquid — drain and use the water packed with canned fruits and vegetables.
- Rainwater — collect from gutters or any clean surface; treat before drinking.
- Streams, rivers, and lakes — always purify before any use.
- Springs — may appear clean but should still be treated before drinking.
Conserving Water During a Shortage
Small changes can dramatically reduce daily water consumption:
- Use paper plates and cups to eliminate dishwashing water entirely.
- Use baby wipes or hand sanitizer for personal hygiene instead of washing.
- When bathing, use a damp cloth rather than showering.
- Combine laundry batches — use the same wash water for multiple small loads, lighter items first.
- Cook meals that require minimal water. Rice and beans require water for cooking; dipping into canned goods requires none.
- Prioritize drinking and cooking water; reduce sanitation use first.