For most UK homes, the safest and simplest way to store emergency drinking water is to keep unopened commercially bottled water in its original packaging. Store it in a cool, dark place away from heat, sunlight, fuels, pesticides and cleaning chemicals. Keep the seals intact, follow the manufacturer’s storage instructions and rotate each bottle before the date printed on its label.
Water can also be stored in refillable containers, but this requires more work. The container must be suitable for drinking water, properly cleaned and sanitised, filled from a safe supply, tightly closed, dated and routinely emptied and refilled. It should never be a container that previously held fuel, bleach, pesticides or another chemical.
Use sealed bottled water where possible
The GOV.UK Prepare guidance on water outages recommends purchasing and storing bottled water instead of filling containers with tap water. Commercially bottled water is already sealed in food-grade packaging, giving it longer-lasting safety and quality.
Sealed bottled water also avoids several opportunities for contamination:
- the container does not need to be cleaned at home;
- hands do not come into contact with the inside of the bottle or cap;
- the water is bottled under controlled conditions;
- the original label provides storage and date information; and
- individual bottles can remain sealed until they are required.
Commercial bottled water is therefore the better default for a household emergency supply. Refillable containers are most useful when cost, storage layout or the quantity required makes an entirely shop-bought reserve impractical.
Store enough water for the household
Safe storage begins with a realistic quantity. Too little water will not cover essential needs, while an unnecessarily large reserve can become difficult to lift, inspect and rotate.
GOV.UK Prepare gives two useful daily planning figures:
- 2.5 to 3 litres per person per day as a minimum drinking-water quantity.
- 10 litres per person per day for greater comfort, including basic cooking and hygiene.
Our guide to how much emergency water you should store explains the difference between the drinking-only minimum and a more practical household allowance. The emergency water calculator can then calculate the quantity for your household.
Add separate allowances for pets, infant feeding and any medical requirement. If someone uses water for medication, wound care or medical equipment, follow the care team’s advice rather than relying on a generic household calculation.
Choose manageable bottle and container sizes
A mixture of sizes is generally more practical than storing everything in large containers. Small bottles are easy to carry, ration and hand to individual household members. Larger containers use space efficiently but become heavy and harder to pour.
| Container size | Approximate water weight | Practical considerations |
|---|---|---|
| 500ml | 0.5kg | Easy to carry and allocate, but creates more packaging. |
| 1 to 2 litres | 1 to 2kg | Manageable for most adults and useful for daily drinking. |
| 5 litres | 5kg | Space-efficient but may be difficult for some people to lift and pour. |
| 10 litres | 10kg | Heavy when full and best used with a suitable dispensing method. |
| 20 litres | 20kg | Difficult to move safely and unsuitable for many household members. |
One litre of water weighs approximately one kilogram before the weight of the container is added. Store heavy containers low down on a stable surface and check that shelving can carry the total load. Do not place a large reserve on one lightweight shelf.
Where should emergency water be stored?
Choose a storage location that remains cool, dark, dry and accessible throughout the year. Suitable spaces might include a low kitchen cupboard, a ventilated under-stairs cupboard or another internal storage area away from heat sources.
- Keep water out of direct sunlight. Sunlight and heat can affect packaging and water quality over time.
- Avoid boilers, radiators and hot-water cylinders. Stored water should remain as cool as practicable.
- Keep it away from chemicals. Do not store drinking water beside petrol, paraffin, paint, solvents, pesticides, household cleaners or strongly scented products.
- Avoid temperature extremes. Cars, greenhouses, uninsulated lofts and many sheds become very hot in summer and may freeze in winter.
- Protect it from physical damage. Keep bottles away from sharp objects, falling tools and places where they are repeatedly knocked or crushed.
- Do not obstruct an escape route. Water must not block a hallway, staircase, door or access to essential equipment.
- Plan for leaks. Avoid storing water above electrical equipment, important documents or anything that would be seriously damaged by a failed container.
If possible, divide the reserve between two suitable locations. This reduces the chance of losing all the water to one localised leak, fire or access problem. Both locations should still meet the same storage requirements and remain easy to inspect.
How to store commercially bottled water
- Inspect every bottle or pack when it is purchased.
- Reject anything with a broken seal, loose cap, leak or damaged packaging.
- Record the date printed on the label.
- Place the earliest-dated water at the front.
- Keep the bottle sealed until it is needed.
- Check the manufacturer’s storage and after-opening instructions.
- Rotate the water into normal household use before its label date.
- Replace the quantity used so the emergency total remains complete.
Do not remove the original label. It identifies the product and preserves the manufacturer’s date, batch information and storage instructions. If you add a rotation sticker, place it where it does not cover any of these details.
Does bottled water expire?
Commercial bottles carry date and storage information that should be followed. Even if the water itself appears unchanged, the bottle, seal and storage history all matter. An emergency is a poor time to debate whether an old or badly stored bottle remains suitable.
Use the oldest suitable bottles in normal daily life before the printed date and replace them during an ordinary shop. This avoids waste and keeps the emergency supply comfortably within the manufacturer’s intended storage period.
Do not assume that every brand has the same shelf life. Use the date and instructions on each individual package rather than applying a single number to the entire supply.
Can tap water be stored in refillable containers?
Yes, but this is a secondary option because contamination can be introduced through the container, cap, tap, hands or filling process. Use a purpose-made container sold as suitable for potable or drinking water, with a secure closure and an opening that can be cleaned properly.
A suitable refillable container should be:
- made from material intended for contact with drinking water;
- durable and in good condition;
- free from cracks, deep scratches, stains and persistent smells;
- capable of being closed tightly;
- designed so that every internal surface can be cleaned; and
- manageable when completely full.
Follow the manufacturer’s instructions concerning cleaning, filling, storage, stacking and maximum service life. Replace a container if its cap no longer seals, its dispensing tap leaks or its internal surfaces can no longer be cleaned effectively.
Never reuse a chemical container
Never store drinking water in a container that previously held fuel, oil, bleach, pesticides, solvents, cleaning fluid or another chemical. Washing does not make such a container suitable for drinking water.
Do not rely on an unmarked second-hand container unless its original purpose and material can be verified. A blue plastic container is not automatically approved for drinking water simply because it resembles a purpose-made water carrier.
How to clean and fill a reusable water container
Check the container manufacturer’s instructions first. Some containers, caps and dispensing valves require a particular cleaning method or must be dismantled before they can be sanitised properly.
- Wash your hands. Clean the work surface and keep the cap away from dirt and splashes.
- Inspect the container. Check the body, neck, cap, seal and dispensing valve for damage.
- Wash it thoroughly. Use soap or washing-up liquid and safe water, following the manufacturer’s directions.
- Rinse completely. Remove all traces of the cleaning product.
- Sanitise it correctly. Follow the container manufacturer’s method or current public-health guidance. Do not improvise a chemical concentration or use scented, thickened or otherwise unsuitable bleach.
- Allow it to air-dry if directed. Avoid touching the inside of the container or cap.
- Fill it from a safe cold-water tap. Ideally use a tap connected directly to the mains drinking-water supply.
- Close it immediately. Fit the cap tightly without touching its internal surface.
- Label it. Write “drinking water” and record the filling date.
- Store it correctly. Move it to the prepared cool, dark storage location.
The US Centers for Disease Control and Prevention’s emergency-water guidance provides a detailed cleaning and sanitising method for home-filled containers. It also recommends replacing home-filled water every six months. This is useful supplementary guidance for refillable containers, while the primary UK recommendation remains commercially bottled water.
Use water from a mains drinking-water tap
Water for home filling should come from a tap known to provide safe drinking water. In an older UK property, the kitchen cold tap may be connected directly to the mains while some bathroom taps are supplied by a loft tank.
The Drinking Water Inspectorate’s guidance on storage tanks and cisterns says a mains-connected tap should ideally be used for drinking, food preparation and cleaning teeth. If you do not know which taps are mains-fed, ask a qualified plumber or the person responsible for the property’s plumbing.
Do not fill the emergency reserve while the water supplier has issued a boil-water, do-not-drink or do-not-use notice unless the supplier’s instructions specifically say the water is suitable for storage after treatment. Filling containers before receiving or checking the notice could preserve contaminated water.
How often should stored water be replaced?
| Type of stored water | Rotation rule |
|---|---|
| Unopened commercially bottled water | Follow the date and storage instructions printed by the manufacturer. Rotate it into normal use before that date. |
| Water filled into a reusable container at home | Date it and replace it every six months, following the supplementary CDC recommendation. |
| Opened bottle or container | Keep it tightly closed, follow the label and use it promptly. Do not assign a longer period than the manufacturer provides. |
| Water boiled during a boil-water notice | Follow the incident instructions. The Drinking Water Inspectorate says to refrigerate boiled water in a clean container and discard it after 24 hours if unused. |
A twice-yearly household check is a convenient way to replace home-filled water and inspect the entire supply. During the check:
- confirm that the planned quantity is still present;
- look for leaks, loose caps and damaged seals;
- check every manufacturer’s date;
- inspect reusable containers and dispensing valves;
- check the storage area for heat, damp, pests and chemicals;
- replace home-filled water that has reached six months; and
- review allowances for babies, pets and medical needs.
Avoid contaminating the water when you use it
Stored water can be safe when opened and then contaminated during dispensing. Clean hands, utensils and closures are therefore important.
- Pour water from the container rather than dipping a cup, hand or utensil into it.
- Use a clean dispensing tap or pump designed for that container.
- Do not touch the inside of the cap, neck or outlet.
- Keep the container closed between uses.
- Do not drink directly from a bottle that will be shared.
- Use a clean cup for each person.
- Follow any instruction to refrigerate the water after opening.
- Do not top up a partly empty container with new water.
If a large container cannot be refrigerated, open it only when needed and use it as promptly as practicable. Several smaller sealed containers may be safer and easier to manage than one large container repeatedly opened over several days.
When should stored water be discarded?
Do not use stored water for drinking, preparing food, brushing teeth, taking medicines or cleaning feeding equipment if:
- the original seal is unexpectedly broken;
- the bottle or container is leaking;
- the cap has become loose or damaged;
- the container is swollen, split, brittle or badly deformed;
- the water has an unexplained colour, cloudiness, particles, taste or smell;
- floodwater, sewage, chemicals or pests may have contaminated the closure;
- the storage history is unknown;
- a home-filled container was not cleaned correctly;
- the water came from a supply subject to an incompatible safety notice; or
- there is any reason to think the container previously held a chemical.
Do not taste suspicious water to decide whether it is safe. Boiling and domestic filter jugs do not provide a universal solution for unknown contamination. Follow the water supplier, local authority or public-health instructions for the particular incident.
Special care for babies and medical needs
Bottled water is not sterile. The NHS guidance on making up baby formula says bottled water is not normally recommended because it may contain too much sodium or sulphate. It can be used in rare circumstances when drinking water is unavailable or contaminated, but the normal formula-preparation method and any additional official advice must still be followed.
Ready-to-feed liquid formula can reduce the need to boil water during an emergency, although feeding equipment still has to be handled hygienically. Store and use it according to its label.
Anyone who needs water for a medical device, medicine, dialysis, wound care or another clinical purpose should ask their care team what type and quantity of water must be stored. Ordinary bottled drinking water may not be suitable for every medical use.
Do not count rainwater as drinking water
Water from a water butt, roof, pond, river, swimming pool or flood is not part of the safe drinking reserve. GOV.UK Prepare warns that water-butt water may contain bacteria or disease and should not be drunk. It may have limited non-drinking uses, such as watering plants or flushing a toilet when the sewerage system is operating and official advice permits it.
Domestic filter jugs are designed mainly to alter characteristics such as taste or hardness. They should not be treated as a way to convert rainwater, floodwater or an unknown source into safe drinking water.
Stored water during a supply incident
Check the water company’s messages before deciding which water to use. A complete loss of supply, a boil-water notice, a do-not-drink notice and a do-not-use notice require different responses. The guide to what to do during a water supply outage explains these distinctions.
- No supply: use the stored reserve for drinking, essential food preparation, medicines, infant needs and basic hygiene.
- Boil-water notice: follow the notice exactly. Do not assume stored tap water filled during the affected period is safe.
- Do-not-drink notice: use bottled water or the alternative supply specified by the authorities. Do not assume boiling makes the tap water suitable.
- Do-not-use notice: avoid contact with the tap water and follow every restriction in the notice.
The Drinking Water Inspectorate’s boil-water guidance says water should be brought to a rolling boil, allowed to cool naturally and stored in a clean container in the fridge. It should be discarded after 24 hours if unused.
Safe drinking-water storage checklist
- Prefer unopened commercially bottled water for the emergency reserve.
- Keep water in its original labelled packaging where possible.
- Use only purpose-made potable-water containers for home filling.
- Never reuse a container that held fuel, bleach, pesticides or chemicals.
- Fill reusable containers from a safe cold-water drinking tap.
- Clean and sanitise containers according to reliable instructions.
- Label home-filled containers with their contents and filling date.
- Replace home-filled water every six months.
- Follow the manufacturer’s date for commercially bottled water.
- Store water somewhere cool, dark and away from chemicals.
- Keep heavy containers low down on a stable surface.
- Use smaller containers for anyone unable to lift or pour a large one.
- Inspect caps, seals, bottles and storage conditions twice a year.
- Avoid touching the inside of containers, caps and dispensing outlets.
- Discard water if its safety, source, seal or storage history is uncertain.
Drinking-water storage resources
- GOV.UK Prepare water-outage guidance covers recommended quantities, bottled-water storage, vulnerable household members and unsafe rainwater.
- Drinking Water Inspectorate guidance on tanks and cisterns explains mains-fed taps, approved tank materials, covers, temperature and maintenance.
- Drinking Water Inspectorate boil-water guidance explains boiling, cooling, refrigerated storage and the 24-hour limit during a notice.
- NHS baby-formula guidance explains why bottled water is not sterile and how formula should be prepared when normal drinking water is unavailable.
- US CDC emergency-water storage guidance provides supplementary instructions for choosing, cleaning, filling, labelling and rotating reusable containers.
- GOV.UK bottled drinking-water rules explain the hygiene, sealing, food-grade packaging and testing requirements applied to commercially bottled drinking water in England.
