Emergency water storage: how much, in what, and for how long

Water planning is simple arithmetic and one material decision. The container matters as much as the volume.

How much to store

Two kinds of figure get quoted, and they answer different questions. Household preparedness advice sizes a reserve that bridges a cut of a few days to two weeks. Ready.gov and the CDC both say to store at least one US gallon, about 3.8 litres, per person per day for drinking, cooking and basic sanitation, which comes to about 53 litres per person for two weeks. The UK government gives 2.5 to 3 litres a day for drinking, and 10 litres once basic cooking and hygiene are included. Use our jerry can sizing calculator to turn a headcount into a container count.

Household minimums or the Sphere figure

The humanitarian figure is larger because it covers everything a person needs from the store. The Sphere Handbook, the reference standard for humanitarian response, sets a minimum of 15 litres per person per day for drinking and domestic hygiene. Its own table splits that into 2.5 to 3 litres of drinking water, counting what goes into food, 3 to 6 for basic cooking and 2 to 6 for basic hygiene, a total of 7.5 to 15. WHO Technical Note 9 gives the same table.

Use a household figure for a home reserve that keeps people drinking and eating through a short cut, while bottled water or a bowser covers washing. Use the Sphere figure where the store is the only supply for weeks: a shelter, a camp, an agency planning for a population, or a household that wants to cover washing from its own cans. A three-day home reserve and a camp supplying thousands for months sit at opposite ends of that range. Sphere treats 15 litres as a floor, not a ceiling. It accepts 7.5 litres for a short time in the acute phase of a drought, and puts the minimum for an urban, middle-income setting at 50.

Sphere also sets two access indicators. The maximum distance from any household to the nearest water point is 500 metres, and queuing time at a source should stay under 30 minutes. Those two indicators exist because supply that is adequate on paper is not consumed if collecting it takes too long. WHO’s 2003 review of domestic water use found that where a round trip takes 5 to 30 minutes, household use is unlikely to exceed 20 litres a person a day, and beyond 30 minutes it often falls below 5.

Distance and queuing time decide whether the volume target is met or missed. A household that can carry more per trip makes fewer trips, and carrying capacity is the one variable in that equation a procurement decision controls directly.

How many gallons of water per person for 3 days, 2 weeks or a month?

At one US gallon per person per day, the rate CDC and Ready.gov give, one person needs 3 gallons (11.4 litres) for three days, 14 gallons (53 litres) for two weeks and 30 gallons (114 litres) for a 30-day month. CDC asks for three days at least and a two-week supply if possible. A household of four needs 12, 56 and 120 gallons: 45, 212 and 454 litres.

Each row answers a different question. Drinking only is the top of the 2.5 to 3 litres that WHO Technical Note 9 gives for survival (Table 9.1), and it leaves nothing for cooking or washing. The gallon a day covers drinking, cooking and basic sanitation for a home reserve. The Sphere minimum of 15 litres, the top of the same table’s 7.5 to 15 litre total, covers drinking, cooking and hygiene where the store is the only supply.

The gallons are US gallons of 3.785 litres (NIST SP 811). An imperial gallon holds 4.546 litres, so the US rate comes to about 0.83 imperial gallons a person a day; plan in litres in the UK to avoid mixing the two. The jerry can sizing calculator runs the sum for any headcount and number of days. On a vehicle, payload limits the store first, as overland and expedition storage explains.

Average water consumption per person per day in the UK and US

In England the average person uses 136.5 litres of water a day, the Environment Agency’s figure for 2024/25, and an American uses 82 US gallons, about 310 litres, at home (EPA WaterSense, from USGS data for 2015). A one-gallon emergency reserve is under 3% of the English figure. The difference goes on flushing, bathing, laundry and outdoor watering; EPA WaterSense puts outdoor use alone at more than 30% of US household water use.

Design standards sit close to the average. Regulation 36 of the Building Regulations 2010 caps the estimated water use of a new home in England at 125 litres per person per day, or 110 where the planning permission makes that optional requirement a condition. The Welsh version sets 110 for new-build homes. England’s targets, as the Environment Agency reports them, are 122 litres per person per day by March 2038 and 110 by 2050.

Size the reserve from the emergency rates and plan the rest of the household’s water apart from it. WHO Technical Note 9 puts a conventional flushing toilet at 20 to 40 litres per user per day (Table 9.2), more than the whole Sphere minimum, so drinking water kept in cans should not go down the toilet. The same note cites research that puts the least water for essential health and hygiene at 20 litres a person a day, and asks relief work to build up to it.

Water storage containers for home and business: sizes and full weights

Water storage containers run from a 5 litre can to a fixed tank, and the weight when full decides where each one belongs. Water weighs about 1 kg a litre, so a full 20 litre jerry can weighs 21 to 24 kg and a full 1,000 litre IBC more than a tonne.

Can weights come from our product pages and the ICRC’s 1 kg specification for a 20 litre HDPE jerrycan; the IBC row adds NHVR’s 52 to 65 kg empty tote. For anything carried, the lift decides. HSE’s guideline filter for a load held close to the body between knuckle and elbow height is 16 kg for women and 25 kg for men (INDG143, Figure 1). It covers carrying up to about 10 m without a rest. HSE says the filters are not safe limits, and a heavier load calls for a fuller assessment. CDC’s planning guide for hospitals warns that containers over 7 US gallons, about 26 litres, may be too heavy for one person to lift (section 7.6).

Past 25 litres a container stops being carried and becomes a store you draw from. The same CDC guide puts a 55 gallon drum on a floor that can take its full weight and draws it by siphon or hand pump on food-grade tubing (section 7.6.1). Our guides to 205 litre drums, IBC totes and jerry can sizes cover each format. A fixed tank that holds mains water at atmospheric pressure is a cistern under the Water Supply (Water Fittings) Regulations 1999. In England and Wales every storage cistern must have a cover that excludes light and insects (Schedule 2, paragraphs 1 and 16(4)(b)).

How many 20 litre or 5 gallon containers, or a whole-house tank?

A household of four storing one US gallon each a day needs three 20 litre cans for three days, 11 for two weeks and 23 for a month. In 5 US gallon containers of 18.9 litres it needs 3, 12 and 24. At the Sphere minimum the month grows to 1,800 litres: 90 cans, or two 1,000 litre IBCs.

Counts are rounded up to whole containers; jerry can sizes covers the other can formats. Standing side by side on their 35.2 by 18 cm base, our 20 litre stainless cans fit five to a metre of shelf at least 36 cm deep. A month for four takes about 4.6 m of shelving, and each metre carries 119 kg of can and water. CDC’s planning guide for hospitals says to stack containers no higher than the maker recommends and to check that the floor can bear a large store (section 7.7). The food-grade HDPE jerrycan has a stackable L-ring body.

Rotation sets the practical ceiling for containers. CDC says to replace water you store yourself every six months, so 23 cans means emptying and refilling about one a week, and the Sphere month of 90 cans means 15 a month. Past what a household or a site will turn over by hand, a fixed tank piped into the supply makes more sense, because daily use draws its water through and replaces it. In England and Wales the Water Supply (Water Fittings) Regulations 1999 then apply. The system needs a device against backflow (Schedule 2, paragraph 15). The cistern must be sized and connected so that water circulates without stagnant areas (paragraph 16(5)). A pump or booster drawing more than 12 litres a minute from a supply pipe needs notice to the water company and its consent before work starts (regulation 5). Our guide to WRAS approval explains how a fitting shows it meets them.

Fortitude21 makes the portable side of this: 5, 10 and 20 litre stainless cans and 5 to 30 litre food-grade HDPE jerrycans. We do not make fixed tanks. Stainless steel vs plastic water containers compares the two materials for a store kept for years, and food-contact certification lists the documents to ask for. Emergency water for care homes, schools and businesses works the same sums for a building full of people.

The container decides how long it keeps

Water itself does not expire, but its container and handling do. Store water in a food-grade material that does not leach or taint: AISI 304 stainless steel, or a food-grade HDPE can. A galvanized steel fuel can is the wrong choice: zinc can leach into what a can holds, and the US FDA Food Code keeps galvanized metal off food-contact surfaces used with acidic food. Stainless has the advantage that it can be cleaned, sterilised and reused indefinitely without holding odour.

Opacity does as much work as material and costs nothing to specify. Light is what algae need, so a translucent container in a lit room grows what an opaque one in the same room does not, and the difference shows within weeks in warm conditions. Where a translucent wall is unavoidable, the answer is the storage location: a dark cupboard makes a translucent can behave like an opaque one, and a sunny yard does the reverse.

Stainless or HDPE

Both are safe for water; they suit different jobs. Stainless 304 takes repeated cleaning and sterilising, holds no smell or taste, and lasts for decades, which earns its cost where the store stays in place and gets reused. HDPE is lighter and cheaper, so it wins where you ship water out and store it in volume. If you are weighing grades, see stainless 304 versus 316, and confirm any can against food-contact certification before you fill it.

For humanitarian procurement, Sphere describes the container. The 2018 handbook asks for two water containers of 10 to 20 litres per household, one for collection and one for storage, sized for the people who carry the water. Containers should have lids and be kept clean and covered, and a storage container should have a narrow neck or a tap. Where supply is intermittent, Sphere asks for larger storage containers.

Read that list against a jerrican and each clause has a reason. A narrow neck stops a hand or a cup entering the stored water, which is the commonest recontamination route in a camp. A tap draws without opening the container at all. Two further points are not in Sphere’s list but belong in a tender: an opaque wall blocks the light algae need, and a smooth interior without ribbing or rough seams gives biofilm nothing to hold. That is the argument for a 20-litre pattern over an improvised vessel, and it is the argument a tender is usually written against.

The two-container split matters as much as the total. One vessel travels and one stays, because a container that does both is opened, carried, set down and refilled constantly, which is where contamination enters. A store built to that pattern needs collecting cans and storage cans as separate line items rather than one number divided by twenty.

Food-grade water containers: materials, colour and approvals

A food-grade water container is one whose maker declares the body, cap and seal fit for contact with food, with documents for your market. CDC advises FDA-approved food-grade containers because they will not transfer toxic substances into the water. In the EU, Article 3 of Regulation (EC) No 1935/2004 bars a contact material from passing its constituents into food in amounts that could endanger health, make an unacceptable change to the food or spoil its taste and smell. Food-grade HDPE and AISI 304 stainless steel are the usual materials for water cans, compared in stainless steel vs plastic water containers; food-contact certification lists the documents to ask for.

The wall and the closure count as much as the polymer. CDC’s hospital guide prefers hard PET bottles to thin, milky-white 1 and 2.5 gallon HDPE jugs, which can puncture, or open when dropped (section 7.6.2). Its household advice asks for a tight top, an unbreakable body and, where possible, a narrow neck, which an open bucket lacks (food-grade buckets). Colour proves nothing: no rule we found sets one for water cans, and blue marks kerosene in some fuel-can schemes (jerry can colours). Public bodies ask for darkness instead: CDC says to keep containers away from direct sunlight, and an opaque wall does that wherever the can stands.

WRAS approval and NSF/ANSI/CAN 61 answer a different question: whether a product is fit to connect to a drinking water system. The Water Fittings Regulations 1999 do not apply to fittings that are not connected to a water undertaker’s supply (regulation 2(3)), so a can you fill at the tap and carry away sits outside them. NSF/ANSI/CAN 61 sets health-effects requirements for drinking water system products and, by its own section 1.1, none for taste, odour or microbial growth. CDC’s hospital guide asks for it on temporary storage tanks over 55 gallons; we found no rule that asks it of a hand-filled can. Fortitude21 holds neither a WRAS approval nor an NSF/ANSI/CAN 61 listing.

Our 5, 10 and 20 litre stainless water cans are AISI 304 across the wetted path, with a mill certificate for the grade on request. The food-grade HDPE jerrycan, 5 to 30 litres in natural translucent resin, has a food-contact declaration, on request, that covers the cap and liner as well as the body. The blue NATO steel water can is pressed steel whose interior specification decides whether it suits drinking water in your market; for a food-grade certificate, specify stainless.

Keep it cool and dark

Sunlight and warmth are what turn clean water green. Light drives algae, and heat speeds any bacteria already present, so a can left in a sunny yard grows a bloom that a cool, dark cupboard would have stopped. Keep containers sealed, out of direct sun, and as cool as your space allows. For long storage or uncertain source water, treat it per your local public-health guidance.

Temperature does the other half of the work and is easier to control than people assume. Reaction and growth rates roughly double for every ten degrees, so water at 30 °C is ageing several times faster than the same water at 10. A garage wall shared with a house, a north-facing store, or simply a lower shelf rather than a higher one each buy a real difference without any equipment. Cool and dark is two decisions, made once.

Why stored water goes off at all

Water does not expire. What changes is everything around it: the container leaches, light drives growth, and the residual disinfectant that made tap water safe dissipates over weeks.

Municipally treated water arrives with a small chlorine residual that suppresses anything that gets in. That residual fades in storage, and from then on the water is only as clean as the container and the moment it was filled. Nothing has spoiled; the protection has simply run out.

This is why the container choice does more work than any treatment. An opaque or metal container blocks the light that algae need, a smooth wetted surface gives biofilm nothing to hold, and a seal that holds keeps out what would otherwise arrive. Get those three right and rotation is a routine precaution.

How to fill, seal and label water storage containers

Wash and sanitise a food-grade container, fill it with clean water, close it with a tight lid, label it “drinking water” with the date, and replace the water every six months. That is CDC’s method, and Ready.gov gives the same six-month interval for water that was not commercially bottled. Bought water starts ahead: CDC calls unopened bottled water the safest source in an emergency, and the UK Government’s Prepare site recommends buying it over filling your own containers, because it comes sealed in a food-grade bottle.

CDC’s draw step keeps hands and dirty scoops out of the water. A narrow neck lets you pour instead of scoop, and a tap, as on our 20 litre stainless dispensing can, draws without opening the container; confirm the tap seal for drinking water when you order. The UK Prepare site adds that rain-butt water is not for drinking, though it will flush a toilet or water plants. Cleaning and reusing jerry cans gives the sanitising dose, and emergency water for care homes, schools and businesses covers a store of hundreds of cans.

Rotate on a schedule

Rotate stored water every six months, the interval CDC and Ready.gov give, and run it first-in-first-out: draw from the oldest can and refill it to the back of the rotation. Label each container with its fill date so you can see at a glance what to use next. When you empty one, wash it before you refill; our guide to cleaning and reusing jerry cans covers the method for stainless.

The rotation interval is a container decision more than a water one, which is why the same figure is quoted for six months and for five years by different sources. Municipally treated water sealed into a clean, opaque, food-grade container in a cool dark place stays fit for a very long time, because nothing gets in and nothing grows. The same water in a translucent container in a warm garage needs replacing within months.

Two things make rotation easier to actually do. Sizing the store in units one person can move means rotation is a ten-minute job rather than a project, which is the practical case for 20-litre cans over a single large tank. And a store that also serves a routine purpose gets rotated by being used, where a store that only exists for an emergency gets forgotten. A reserve that is drawn on and refilled through the year is fresher than one nobody touches.

Keep water clear of fuel and chemicals

Store drinking water away from petrol, solvents and cleaning products. Vapour migrates, and plastics in particular can pick up a fuel taint through a sealed wall over time, which ruins the water without any spill. A common mistake makes this worse: reusing old juice or milk bottles, or a former fuel can, for stored water. Sugar residue feeds bacteria, and a fuel can never fully sheds its smell. Start with a container built for water.

The mechanism behind the fuel case is absorption rather than residue, which is why rinsing does not fix it. Hydrocarbons enter the polymer wall and the gasket and come back out slowly for a long time, so a can that rinses clear and dries completely can still taint water weeks later. The smell test is useful and it runs one way only: any smell proves contamination, and no smell proves nothing at all.

Why the NATO form helps

A stainless NATO-pattern water can stacks, seats in standard holders, and carries by the same handles as the fuel cans alongside it, which suits a mixed emergency store. See the water and food-grade range.

Stacking makes a household or agency store practical. Rectangular cans use a cupboard, a pallet or a shelf completely, so a two-week reserve for a family occupies a footprint somebody will give up. The same volume in round containers does not fit anywhere convenient and gets reduced. A store that fits the space available is the one that still exists in a year.

Match the can to the job

Food-grade, sealed and rotated. We make these cans for water storage.

Common questions

How much water should I store per person?

For a home reserve, store at least one US gallon, about 3.8 litres, per person per day, the Ready.gov and CDC figure for drinking, cooking and basic sanitation: about 53 litres per person for two weeks. Drinking alone is 2.5 to 3 litres a day. Where the store is the only supply, for a shelter, a camp or an agency, plan on the Sphere Handbook minimum of 15 litres per person per day for drinking, cooking and basic hygiene. That is 840 litres for four people over two weeks.

How long does stored water stay drinkable?

CDC and Ready.gov both say to replace water you store yourself every six months, and CDC says to observe the expiration date on bought bottled water. Keep it in a clean, sealed, food-grade container labelled “drinking water” with the date, at 10 to 21 °C (50 to 70 °F) and away from direct sunlight, as CDC advises. A cool, dark store slows algae and bacteria, but neither body gives a longer interval for good conditions.

What is the best container for emergency water?

Food-grade stainless steel for long-term storage, because it blocks light, takes no taint and cleans reliably. Food-grade HDPE is the cheaper option and works well if kept out of sunlight. Avoid any container that has held fuel, chemicals or non-food products.

Should stored water be treated before storage?

Municipally treated tap water usually needs nothing more if the container is clean and sealed. Water from an untreated source should be disinfected before storage and again before drinking. Rotate and re-fill on a schedule rather than relying on treatment to hold indefinitely.

Can you put petrol or diesel in a water jerry can?

Not petrol in Great Britain. Schedule 3 of the Petroleum (Consolidation) Regulations 2014 limits a portable petrol container to 10 litres in plastic or 20 in metal. The container must be made of material that petrol and sunlight will not significantly degrade, and marked PETROL and HIGHLY FLAMMABLE with a hazard sign. A water can is not designed or marked for petrol. Diesel falls outside those regulations, but a can that has held any fuel never goes back to drinking water.

What is a water storage container called?

It depends on the size and whether it moves. A portable can of up to about 30 litres is a jerry can or jerrican, and a 205 litre or 55 US gallon barrel is a drum. A 1,000 litre tank in a steel cage on a pallet is an intermediate bulk container, or IBC. In UK water law a fixed tank is a cistern, defined in the Water Supply (Water Fittings) Regulations 1999 as a fixed container for holding water at atmospheric pressure.

What does potable water storage mean?

Potable water is water fit to drink, and potable water storage keeps it fit to drink until it is used. EU law counts water for drinking, cooking, food preparation or other domestic purposes as drinking water whether it reaches you from the mains, a tanker, a bottle or a container (Directive (EU) 2020/2184, Article 2(1)). A home store therefore needs a food-grade container, a tight seal, a dated label and, as CDC advises, fresh water every six months.

Do water jerry cans rust?

A stainless steel water can resists rust in drinking water; a painted steel can rusts once its coating is breached. A UK code of practice for stainless steel in drinking water accepts grade 304 below 200 ppm chloride in flowing water, and 50 ppm where chloride can concentrate, as in the crevice under a cap gasket. Do not leave bleach or salty water standing in a stainless can. HDPE cannot rust. Retire any steel can with rust inside.

Are collapsible water containers good for storage?

They suit water you move or set up when needed, less a reserve kept full for months. CDC’s planning guide for hospitals lists the weak points of collapsible pillow and bladder tanks: perforation, fabric weakened by age, sunlight or repeated use, and the loss of disinfectant during long storage. A small folding can has the same thin, flexible wall. Keep the reserve in rigid food-grade cans and hold a collapsible container for collecting water from a bowser.

What size water storage tank do I need?

Multiply people by days by litres per person per day. A family of four storing CDC’s 1 US gallon, about 3.8 litres, a day for two weeks needs about 212 litres: just over one 205 litre drum, or eleven 20 litre cans. At the Sphere minimum of 15 litres a day the same family needs 840 litres, which fits in a 1,000 litre IBC. Check the floor first, because a full IBC weighs more than a tonne.

What is the best water container for camping?

One you can carry full, that seals tight and keeps light out. HSE’s lifting filter for a load held close to the body is 16 kg for women and 25 kg for men, so a 10 litre can, 12.8 kg full in our stainless version, suits most people. CDC advises keeping stored water at 10 to 21 °C and out of direct sunlight, so keep the can in shade rather than on a sunny seat or roof, and choose stainless or opaque plastic.

How much water per person is provided in a liferaft equipped with a desalting apparatus?

One litre of stored fresh water per person, with the desalting apparatus making the other half litre. Paragraph 4.1.5.1.19 of the IMO Life-Saving Appliances Code, as amended by Resolution MSC.218(82), requires 1.5 litres of fresh water for each person the liferaft may carry. A desalting apparatus able to produce an equal amount in 2 days may replace 0.5 litre a person, or a manual reverse osmosis desalinator 1 litre. The water is packed in sealed watertight containers that resist corrosion.

How much emergency water does a long-term care facility need?

US federal law sets no volume. 42 CFR 483.73(b)(1) makes a long-term care facility plan food, water, medical and pharmaceutical supplies for residents and staff, whether they evacuate or shelter in place, and the plan is reviewed at least once a year. Counties can set a figure: Miami-Dade requires 3 US gallons, about 11.4 litres, per person per day for the licensed capacity, for at least three days. For a 100-bed home that is 900 gallons, about 3,400 litres, or 171 twenty-litre cans.

How heavy is a 5 gallon water container when full?

About 19 kg (42 lb) of water plus the container, since 5 US gallons is 18.9 litres. That is above HSE’s lifting filter of 16 kg for women and below the 25 kg filter for men, for a load held close to the body (INDG143). CDC’s hospital planning guide says containers over 7 gallons may be too heavy for one person to lift, and that a hand-operated pump can dispense from 3 and 5 gallon jugs, so a full one can stay on the shelf.

What makes a water container heavy duty for outdoor use?

A rigid body that passes drop and leak tests when full, and a wall or a spot that keeps sunlight off the water. The ICRC’s quality-control specification for a 20 litre rigid jerrycan asks for food-grade HDPE with no recycled plastic, a can that stands by itself, and a handle that holds 20 litres for 10 minutes. It asks for a cap that does not leak upside down, and no leak after two drops full from 1.5 m onto concrete. CDC advises keeping stored water out of direct sunlight.

How long does a 55 gallon drum of water last?

About 55 days for one person, or just under two weeks for a family of four, at the CDC and Ready.gov rate of one US gallon per person per day. The drum holds 208 litres. At the Sphere minimum of 15 litres a day it lasts one person about 14 days and four people about three and a half. Stand it where the floor can take its full weight, which CDC’s hospital guide puts at over 400 pounds.

How much water does a person need to drink a day?

About 2.5 to 3 litres, the survival figure for drinking and food that WHO gives and the UK government repeats. Ready.gov says a normally active person needs about three quarters of a US gallon, 2.8 litres, of fluid a day. WHO's 2003 review puts hydration at a minimum of 2 litres for an average adult in average conditions, rising to 4.5 in tropical climates. Ready.gov adds that very hot weather can double water needs, and children, nursing mothers and sick people may need more.

How much water do you need per person per day when camping?

At least one US gallon, about 3.8 litres, per person per day, the Ready.gov and CDC household rate, with more for washing up. Ready.gov says very hot weather can double water needs, so a desert camp may need 7.6 litres. Backpackers carry what they will drink before the next source and treat the rest. CDC warns against drinking straight from a clear mountain stream, and says a rolling boil for one minute, or three above 6,500 feet (about 2,000 metres), kills germs.

How much water do you need per person for a hurricane?

At least one US gallon, about 3.8 litres, per person per day, the rate CDC and NOAA both give, and CDC's hurricane advice adds a gallon a day for each pet. The days differ: CDC asks for three days and a two-week supply if possible, about 53 litres a person, and NOAA for up to seven days. Fill clean containers before the storm in case the supply fails, and CDC suggests filling sinks and baths with washing water.

How much water does one person need for a month?

About 114 litres, or 30 US gallons, at the Ready.gov and CDC rate of one US gallon per person per day. That takes six 20 litre cans. CDC's own target stops at a two-week supply if possible, about 53 litres. Where the store is the only supply and must cover washing too, the Sphere Handbook minimum of 15 litres a day comes to 450 litres a month. Ready.gov says children, nursing mothers, sick people and hot climates may need more.

Why are water storage tanks black?

To keep light out. Algae need light to grow, so an opaque wall, black or any dark colour, stops the green growth a translucent container develops within weeks in warm conditions. The trade-off is heat. A dark container in direct sun warms the water inside it, and warmth speeds the growth of any bacteria already present, so stand an opaque container in shade as well.

Can stored water freeze and split the container?

Yes, if the store drops below 0 °C. Water expands by about 9 per cent as it turns to ice, so a can filled to the brim has nowhere to take the extra volume and can bulge or split a seam. Leave about a tenth of the can empty wherever it may freeze, or keep the store above freezing. Check a can that has frozen for bulging or a weeping seam before you rely on it.

References

The standards and regulations this page relies on, at their issuing body. Where a market rule is named here, check the current revision before you specify against it.

• Sphere Handbook: minimum standards in water supply and hygiene
• WHO — how much water is needed in emergencies
• Ready.gov: water, how much to store per person
• CDC: how to create and store an emergency water supply
• UK Government: get prepared for emergencies, bottled water per person
• WHO: Domestic water quantity, service level and health (Howard and Bartram, 2003)
• NSF/ANSI/CAN 61: drinking water system components
• WRAS: Water Regulations Approval Scheme approvals
• UK Government Prepare: water supply interruptions or outages
• HSE INDG143 — manual handling at work, including the guideline filter weights
• CDC, EPA and AWWA: Emergency Water Supply Planning Guide for Hospitals and Healthcare Facilities (2019)
• NHVR (Australian heavy vehicle regulator): loading guide for intermediate bulk containers
• ICRC/IFRC Standard Products Catalogue: quality-control specification for the 20-litre rigid jerrycan (2022)
• NIST Special Publication 811, Appendix B.9: conversion factors (US gallon 3.785 412 L; imperial gallon 4.546 09 L, exact)
• The Water Supply (Water Fittings) Regulations 1999, Schedule 2, including paragraph 16 on storage cisterns
• Regulation (EC) No 1935/2004: materials intended to come into contact with food
• Directive (EU) 2020/2184: quality of water intended for human consumption
• The Petroleum (Consolidation) Regulations 2014 (SI 2014/1637)
• SCI for the British Stainless Steel Association: operational guidelines and code of practice for stainless steel products in drinking water supply (2002)
• 42 CFR 483.73: emergency preparedness for long-term care facilities
• Miami-Dade Emergency Management: residential health care facility potable water form
• The Water Supply (Water Fittings) Regulations 1999 (SI 1999/1148), regulations 1 to 7 on application, quality and standard, notification and penalties
• NSF/ANSI/CAN 61-2020: Drinking Water System Components, Health Effects (NSF International), copy incorporated by reference in Virginia regulations (12VAC5)
• WRAS: Material Approval Guidance, WRAS.Appr-310 version 4.0 (November 2024)
• Environment Agency: Water efficiency must become national priority, says EA (press release, 18 November 2025), reporting Water resources 2024-2025, the annual review of water company performance
• The Building Regulations 2010 (SI 2010/2214), regulation 36: water efficiency of new dwellings (England and Wales versions)
• US EPA WaterSense: statistics and facts, citing USGS Estimated Use of Water in the United States in 2015
• IMO Resolution MSC.218(82), adopted 8 December 2006: amendments to the International Life-Saving Appliance (LSA) Code, including paragraph 4.1.5.1.19 on liferaft fresh water

Last reviewed 26 October 2026 by Clarence Cheang, Co-Founder.