How Much Emergency Water Should You Store?
Build a realistic household water target from a clear baseline, then adjust it for climate, health, pets, and practical storage limits.
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- 6 minutes
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Start with a transparent baseline
A common official starting point is at least one gallon per person per day for drinking, cooking, brushing teeth, and limited sanitation. Multiply the number of people by the number of planning days, then make deliberate adjustments rather than treating the result as a guarantee.
Begin with three days if space or budget is limited. Build toward a longer supply over time when local guidance, storage conditions, and container weight make that practical.
- 1Count the people you are planning for.
- 2Choose a realistic number of days.
- 3Add an adjustable allowance for pets and additional household needs.
- 4Check whether the filled containers can be stored and moved safely.
Adjust for real circumstances
Water needs vary. Hot weather, physical activity, pregnancy, illness, disability, and some medical circumstances can increase needs. Pets also vary by species, size, health, and climate, so use appropriate veterinary guidance rather than one fixed allowance.
Keep drinking needs distinct from extra sanitation water. If your target feels too large, build it in safe increments instead of abandoning the plan.
Put this guidance to work
Related mission
Build a Three-Day Water Supply
Use the estimate to support the mission, but verify containers and storage conditions before marking steps complete.
View Preparedness Missions →Related toolkit resource
Open Water Storage Calculator
Calculate gallons, liters, and container estimates without saving household data.
Open Water Storage Calculator →Authoritative references
Review current source and local guidance because recommendations can change.
- How to Create and Store an Emergency Water SupplyCenters for Disease Control and Prevention
- Build an Emergency KitReady.gov