Why this matters
Official minimum amounts vary by climate, health needs and country. Use local guidance as the baseline, then allow for heat, pregnancy, breastfeeding, illness, physical work, food preparation, hygiene and animals.
Treatment depends on the contaminant. Boiling can address many disease-causing organisms, but it cannot remove fuel, toxic chemicals or radioactive material. A do-not-use or do-not-drink notice may require an approved alternative supply.
Before disruption
Prepare now
- Store water in unopened commercial packaging or clean food-grade containers intended for water.
- Keep supplies cool, dark, away from chemicals and in more than one accessible location.
- Label containers, record storage dates and follow local and manufacturer replacement guidance.
- Identify official water-provider alerts and safe collection points before an outage.
- Plan clean containers, safe carrying and assistance for anyone unable to collect water.
When it is happening
Protect the next decision
- Read the exact local notice before filling containers, drinking, cooking, washing or flushing.
- Prioritise safe water for drinking, medicine and essential food preparation.
- Use only the treatment method, quantities and contact times given by public-health authorities.
- Keep clean hands and utensils away from the inside of caps and storage containers.
Plan for real people
Access, care and inclusion
- Count extra water and clean equipment for infant feeding, health care and mobility needs.
- Use container sizes that each person can lift, grip, open and pour safely.
- Include service animals, pets and livestock in a realistic local plan.
- Consider people without storage space, transport, money or control of a shared water supply.
Mental readiness
Protect morale and clear thinking
- A written rationing priority can reduce conflict when supplies are limited.
- Keep familiar drinks only after safe water needs are protected and preparation is safe.
- Share verified supply information with neighbours without creating queues at unconfirmed locations.
Common mistakes
What to avoid
- Using containers that previously held fuel, chemicals or non-food substances.
- Publishing or following a universal chemical dose when products and strengths vary.
- Assuming clear-looking or fast-flowing water is safe.
Evidence and review
Sources behind this guide
These sources are evidence to evaluate, not instructions imported unchanged into this guide. Each source is identified by institution type so you can consider its remit, funding, jurisdiction and limits. Check the original date and current version for your location.
- Technical Notes on WASH in EmergenciesWorld Health OrganizationIntergovernmental institution
For information and context. This combines technical work with member-state processes. Treat it as evidence and institutional guidance, not a guarantee that local services will act or reach you.
- Household Water Treatment and Safe Storage Following EmergenciesWorld Health OrganizationIntergovernmental institution
For information and context. This combines technical work with member-state processes. Treat it as evidence and institutional guidance, not a guarantee that local services will act or reach you.
- How to Make Water Safe in an EmergencyUS Centers for Disease Control and PreventionPublic-health or clinical service
For information and current service context. Check the date, eligibility and jurisdiction, and do not change prescribed treatment without qualified advice.
- Work Out What Supplies You NeedNew Zealand National Emergency Management AgencyGovernment or public authority
For information and context. Useful for current rules, warnings, services and the institution's stated position. It is not a guarantee of timely help, completeness, neutrality or suitability for your household.
Editorial status: first staging edition. Safety-critical instructions will receive specialist and jurisdiction review before public launch.