Home/ Articles/Water
Water
What to do when the water has been turned off
Water supply cut off? How much water to store, safe ways to filter and purify it, and how to keep the toilet working until it is back.
By Slightly Anxious
1st July 2026 26 minute read
IN SHORT
Store at least 10 litres of water per person per day, ideally in 2 litre bottles that are easy to store and ration, and have a way to filter and purify more.
Product links were live when this article was written. If one has changed, the Products page will have an alternative.
Water is the most important thing on earth. As a rough rule-of-thumb, an adult human can survive about 3 weeks without food but only three days without water. We need it for our very existence, to drink but also to cook with and to make our toilets, sinks, showers and baths work, so we can keep hygienic with it. That is washing ourselves and the environment we inhabit, our household and, usually using machines, our pots and dishes and our clothes. We explore how to do this with limited water, which changes a lot of ways we run our lives, in a number of our articles which can be found on our website.
In times of emergency there is a very good chance that you will lose your water supply. Many of you may have already experienced this due to flooding or a water mains bursting. Hopefully, this was only an outage for a short time but a review of recent events suggest that people are spending longer without water and that is even before the potential for more severe emergencies, where the strain on the system will mean even longer waits while the taps are turned off.
How long could it last?
We sincerely hope that, a) you never have to suffer a crisis situation, but unfortunately, as the chance of that not happening grows smaller, we then have to hope that, b) if you do have to endure an emergency it is one where you have a fully functioning water supply. But if this isn’t the case then, c) we really hope you take onboard the importance of this article in convincing you that you really need to have an emergency supply of water. Part of looking after others and yourself responsibly is being prepared for the unexpected.
It took less than 8 weeks from the first case of Covid-19 being recorded in the UK to when national lockdowns were introduced and many people had voluntarily started isolating before then. That is a lifetime compared to an emergency like the September 2024 floods, where the time from the first relevant flood guidance/warning to the actual flooding was less than 24 hours. That is the thing with emergencies, they are by their very nature unexpected and the best way to survive, as many a Guide or Scout will know, is to be prepared. And in this case that means preparing for a life, albeit a week at most, with the taps turned off.
How much water you need
-
Store at least 10 litres per person per day
-
A couple for a week: 140 litres
-
A family of four for a week: 280 litres
-
Plastic bottles and containers: treat as a 6 month shelf life
-
Never store plastic bottles directly on concrete
How much water to store
Guidance on how much water to store varies a great deal, and the figures quoted internationally range from around 7.5 litres per person per day at the bare survival end of the scale, up to 15 litres and beyond once basic hygiene is properly accounted for. Our recommendation is that you store at least 10 litres of water per person per day, because it is the honest middle of that range and, just as importantly, it is an amount that a normal household can realistically find room for. That works out as a daily personal allowance of 3 litres of water for drinking, 2 litres for cooking and cleaning of cooking surfaces and utensils, and 5 litres for handwashing, personal washing and basic household cleaning. We will be straight with you, this is a lean allowance rather than a comfortable one, and at this level laundry is not really happening. If you Google, you will often find that governments recommend that you just store 2-3 litres per person per day. This is purely for drinking. If you want any basic hygiene and cooking during your emergency you will need more.
Where your head will understandably start spinning is when you do the basic maths. For a couple enduring a week without water, they need to store at least 140 litres of water. For a family of four that’s double, 280 litres of water. That is the equivalent of about one and a half full bath tubs, which is a good deal less frightening than it sounds but still needs somewhere to live. This is why the practicalities of water storage are one of the main issues that need consideration in your emergency planning.
For most of us that have suffered water outages due to a water company doing maintenance work, we are usually given a few hours of warning before the taps turn off and that is when we go and fill saucepans, kettles and bottles so we are ready. You can even go as far and purchase a special kit for your bath so that you can use the few hours you have to fill it and due to its liner, you will have about 100 litres of drinking water available: WaterBOB at c.£35-£55. This is a great option in a more ‘run-of-the-mill’ mini-crisis, like a water mains bursting, with the prospect of having the water turned off for just a few hours and you have been pre-warned. Fill a few saucepans and the kettle or even the bath tub and life won’t be too uncomfortable.
This is not, however, what we are preparing for. We are preparing for an emergency where the chances are that the water will be off for up to a week. This doesn’t need to be just due to disruptions with the water supply, other indirect reasons, such as electricity failure, natural disaster or fire can shut your water supply down as well. In this article, we don’t need to dwell on why this could be happening, just that there is a reasonable chance it may. Read our article, ‘Why you’re right to be Slightly Anxious’ to get depressed about the current state of the world and why its only sensible to get prepared.
Taking it that we need to store a rather large amount of water, we need to look at the practicalities and the first step is deciding on where the water is coming from. Do we use what comes out of our taps so copiously in ‘normal’ times or do we just buy it in. If we use tap water then we need containers. If we buy it in then we are buying pre-filled bottles. There are pros and cons to both.
Buying bottled water
Let’s first discuss buying bottled water. Bottled water is usually sold in 330ml, 500ml, 1litre, 1.5litre, 2 litre and 5 litre bottles. Due to the preference of people buying a bottle of water in a shop to carry with them, there is a preponderance of offers for the 330ml and 500ml sizes. Some companies will offer a pallet; a wooden platform that a forklift uses to transport stores, and examples are: a pallet of generic spring water in 330 ml size for £525 which is 63 cases of 40 bottles or 2,520 bottles in total, or 831.6 litres of water making each bottle cost just over 20p each, or a pallet of generic still mineral water in 500 ml size for £489.99, which is 91 cases of 24 bottles each or 2,184 bottles in total, or 1,092 litres of water making each bottle cost just over 22p each. This tells you about the profit margins your local shop is working on the next time they sell you a bottle.
A standard UK pallet is 1.2m x 1m wide and how tall it is depends on the size of the bottles and how many are stacked upon each other. We estimate that in the 330ml example above will be 1.5m high and it states that it weighs 819kg. In the 500ml example, we estimate the pallet to be 1.7m high and it states that it weighs 999kg, just shy of a tonne. The purpose of this maths is to show you that if you have the space, i.e. a garage or outhouse, you could get a pallet delivered directly to your door and you’ve got enough water for a household of 6 people or more likely for 4 living la Vida Loca. If you go for the 5 litre bottles, you can get a pallet of 65 cases, 3x5litre bottles per case for 1,950 litres of water for £300 or just over 15p per litre. The pallet will be an estimated 1.4m high and weigh about 2 tonnes! This is enough for about 12 people living frugally and 6 living easily.
Pallets are not for everyone. You need space and possibly a forklift truck. The advantages you do have is that they are all stored in one place away from your living quarters and obviously as you will have extra bottles, there are opportunities to profiteer from selling to you neighbours at extortionate prices for not being as well prepared as you!(only joking)
We recommend that if you go down the buying bottled water route, going for 2 litre bottles. They are available, they are in the goldilocks zone of ‘not too big’ and ‘not too small’. Bottles that are too big, such as 5l bottles or even 10 litre boxes are great but just weigh too much to be practical. With 2 litre bottles it’s also easier to store them in different locations. More importantly, they greatly assist in the most important job in an emergency situation, the rationing of the water. We hope you are one of the lucky ones in life and can afford the house with a garage or outhouse that has the space to take a pallet of water bottles, so you have an excess of supply. But for many of us, we will be pushed with where to store the hundreds of litres we need and that is based on rather spartan rations already. As anyone who has spent time in groups of humans, be it families, class rooms or student houses, you will already know that not everyone conforms to the idea of ‘fair shares for all’. Whether through ignorance or belligerence, if left unattended there will always be someone who will take more than they should. This is why you must appoint someone with sufficient authority in the household, probably you, to manage the rationing of the water and this is easiest done by handing out 2 litre bottles. We recommend that each household member is supplied with 1 when they wake and then 1 with each of their three meals. Although you can play around with this. This gives people their basic drinking and personal washing allowance for the day. The remaining 12 litres can be used for communal cooking, household cleaning, emergency laundry with a contingency that can be handed out for legitimate purposes, such as taking medicine etc.
Ways to store 140 litres
Option
Capacity
Guide Price
2 litre bottles (72 for a couple)
144 litres
c.£73 plus delivery
25 litre jerry cans (12 for a couple)
300 litres
c.£12-£16 each
PowerChem 10L jerry cans (pack of 10)
100 litres per pack
c.£60-£90 per pack
105L flat tanks (fit under a bed)
105 litres each
c.£140-£180 each
AquaBrick containers (6 pack)
68 litres per pack
c.£200-£275 per pack
WaterBOB bath liner (fill when warned)
About 100 litres
c.£35-£55
Unfortunately when not buying in a pallet load, the cost of water understandably increases. You can get a case of 4 generic still or sparkling 2 litre water bottles for £2.08 or 52p each or 26p per litre. You would need 35 cases (140 x 2l bottles) to make up your minimum requirement for a couple. This will cost you a piffling £72.80 although you will need to look at delivery charges. For a family of four you need to double this.
Where to store it
The next obvious question is where do you store them? Please do read our article ‘Aesthetically Pleasing Packaging with Slightly Anxious’ which tackles one of the key issues of emergency storage, how do you store things without turning your home into a nuclear bunker.
One solution needs a minor additional purchases and that is storing the bottles under your beds. Our research (we asked AI!) suggests that the 72x 2 litre bottles you need to store for a couple, you would have enough space to fit them all upright under a double bed, but you will need bed risers: Usion Bed Risers 6 inch Heavy Duty Furniture Risers at c.£20-£30. Our maths suggests that you would have enough space for 176 (352 litres) upright bottles under a double bed and 112 (224 litres) under a single bed both using risers, so a double bed on its own now covers a family of four with room to spare. Equally, if you laid the bottles flat, while in their packaging in 2x2 format, you can store 126 (252 litres) bottles in two rows under a double bed and 78 (156 litres) under a single bed without risers. This obviously is dependent on you having beds that aren’t divans and have normal clearance levels underneath. You may also not be happy with the idea of having the bottles, although in cases formed by a polythene wrapper, being exposed for a number of reasons. In which case, we suggest that you put the bottles in plastic crates such as the Ikea Samla transparent boxes at c.£8-£12 or Wham 4-Pack Crystal Plastic Stackable Storage Boxes at c.£40-£55. Both of these will fit under beds but can also be stacked vertically of that is required. If you can’t fit all the bottles under the bed then you will need to consider other locations like, an under the stairs cupboard, the floor of a wardrobe under hanging clothes, the floor of an airing cupboard or even behind a sofa. If you have read our article, ‘Aesthetically Pleasing Packaging with Slightly Anxious’ you will see our ideas about storing water under sofas and in Ottomans/footstools.
Storing tap water in containers
The alternative to buying in bottled water, which as you can see is not really that expensive, is just buying the containers and filling them from the taps. British tap water is still some of the best in the world and very drinkable. However, there are some practicalities to deal with first. The main one being that the size of the container you will be filling will not fit into your kitchen sink and under your kitchen tap. You may be lucky enough to have an outside tap with a hose attachment but if not, we recommend the following: a Hozelock Kitchen Tap Connector with a 24mm male head at c.£10-£14. This fixes onto the spout of your kitchen tap, obviously, check to see it’s the correct fitting. If you have a tap with a smooth spout instead of a thread then try a KDP Hose Pipe Clamp Clip Rubber Push-On Tap Connector at c.£8-£12. Then you attach a Mypurecore Blue 12mm 1/2" Cold Water 3m Hose Pipe at c.£12-£16 and pipe the water from your kitchen tap into your choice of container.
It does need saying that you should try and see if you can fill your choice of containers from the bath taps by standing the container in the tub. You can even unscrew the shower head from the shower hose and use that to pipe water into your containers.
As for your choice of water container you are truly spoilt for choice. The issue is where do you store them and can you access them. Theoretically you could just buy a 1,000 litre water container, but that will weigh a tonne when its full so where you fill it is where it stays and is this location the best for repeated access? If you have a garage, outhouse or even basement you could get a 1000l IBC (Intermediate Bulk Container) Water Tank at c.£250-£350, but remember to ensure that any IBC you purchase is new and not refurbished and certified food grade to be safe for drinking water. Or there are 200L plastic storage containers such as the DWZL Water Storage Container at c.£140-£180 and you get 5 of them (£700-£900). The advantage of having a handful of containers instead of one big one is less weight individually and more options of where to store, they are stackable but also spreadable. You will need to factor in delivery costs on top of this. Once installed outside your living quarters, you will need to fill it from a nearby tap and then when needed, transfer water in containers to your household. This can help with the practicalities of rationing as restricting access to this location solves most of the issues.
For those of us without the luxury of extra space, we need containers that are smaller and easily stored around our living space. We think which container you choose will primarily depend on the way your household is set up for storage. If you have some large spaces available then you can have a small number of large capacity containers. If you have smaller spaces available then you will need to have a larger number of smaller capacity containers. Much in the same way as you stored with bottled water. You can mix and match.
One we recommend is the AquaBrick 3 Gallon Long Term Water Storage Container (6 pack) at c.£200-£275. These six stackable water containers have 18 US gallons or almost 68 litres of water capacity. You would need 2 of these 6 packs (136 litres) and then one of their AquaBrick Emergency Water Storage Containers (2 pack) at c.£80-£110 to add on an extra 22.7 litres (6 gallons) to bring you over the required 140 litres for a couple. For four people, you would need 4 of the 6 pack to make 272 litres and then 1 of the 2 pack to add an extra 22.7 litres and bring you over the required 280 litres for 4 people. Thus total cost to store water for a couple could be up to £660 and require 14 Aquabricks, while for 4 people it’s up to £1,210 and requires 26 Aquabricks. Yes they are expensive but due to their design, their stackability, you can fit all you require for a couple under a single bed and all you need for 4 under a double bed if they are stacked two rows high, so you will need bed risers.
A cheaper option may be to get 105L Flat Tanks at c.£140-£180 each. You could fit two under a double bed (do measure first) and one under a single bed, both with bed risers, to give you 315 litres of storage, which is comfortably more than a couple needs and plenty for a family of four, for up to £540. You will need to get taps to go with them and pay for delivery, but this is still a third less than the Aquabricks. The Aquabricks do have the advantage of being made up of 3 gallon (13.6l) bricks which will weigh about the same as 34 tins of baked beans – just about liftable, whereas the 105L Flat Tank will basically be unmoveable. Which is a very good segue to mentioning that if you are storing your water anywhere above the ground floor, you will need to check that the floor can structurally take the extra weight, you don’t want to spend money on preparing for an emergency and then cause one all of your own!
If you’re not going down the admittedly expensive route of Aquabricks and don’t want to raise your beds for the flat tanks, then you are left with purchasing water containers of a manageable size and storing them around your property in available spaces, like those previously mentioned such as an under the stairs cupboard, on the floor of wardrobes, behind sofas, or even inside an Ottoman! There is no escaping the fact that storing large amounts of water around the inside of a property that doesn’t have a garage, an outhouse, a balcony or even a basement is quite challenging. Basically any food safe plastic container is fine, some worthy of consideration are:
-
Thick Plastic Water Tank, Emergency Water Barrel with Spigot, 50l at c.£40-£55 – we like that it’s the shape of a barrel on its side with a pull handle that will make its c.50kg easier to deal with.
-
25 Litre Jerry Can Water Container Storage Tank at c.£12-£16 – who doesn’t like a jerry can, especially at this price as you will need 12 of them (c.£168) for a couple, they’re of a weight most can handle and you can distribute them about the property.
-
PowerChem 10L Jerry Can (pack of 10) at c.£60-£90 – these are 10x 10 litre jerry cans that are stackable at a very low price. At this low weight everyone is transportable. You can buy 3x10 (up to £270) for a couple’s worth of water.
One option for moving water from large storage containers to where they can be used, is the Folding Water Container, 2 Pack 10L Portable Folding Water Bag at c. £10-£14. These are basically foldable carry bags made out of food grade plastic, have strengthened handles, a wide opening with a screw cap.
Keeping stored water safe
You must remember when storing water whether in bottles or in containers to manage your supply of water by using the FIFO method – ‘First-In, First-Out’ if you built up your supply over time or even if the bottles have different use by dates. Which leads us on to the shelf life of your supply. Water has an indefinite shelf life, it’s the container that causes the issue. Plastic is great up to a point, glass is much better but the cost and weight of glass bottles rules it out, so we have to adapt to using plastic containers. This means following a few simple rules:
-
Consider water in plastic bottles or containers to have a 6 month shelf life.
-
Avoid the floor: Do not store plastic water bottles directly on concrete floors; chemicals from the concrete can leach through the plastic. Place them on a wooden pallet or shelf.
-
The "Sniff Test": If "expired" water smells like chemicals or plastic, use it for your "Hygiene Bucket" rather than for drinking.
-
‘Expired’ water is good for plants and for washing so don’t throw down the drain unless you have to
Filtering and purifying water
This leads us to the more survivalist element of emergency water and that is re-using water. If you are in the unfortunate position where you either didn’t store enough drinking water for your emergency or your emergency is lasting longer than expected than you will have to consider what and how you will use your water.
Water is generally categorised into three types; potable water (a posh word for drinking water), grey water (water that has been used for washing and cooking) and black water (water in the toilet). We are storing potable water. Some of which we will use for washing and cooking and once we have, we can use it as grey water which means it can be reused for washing (at a push) and cooking if simply boiling things in containers, never with raw ingredients. What we can do with grey water is filter it.
These filters are de rigueur amongst those people who think that our tap water is unclean and want it purified and each to their own, but what they do provide is a way of turning grey water into potable water in extreme emergencies and clean up our grey water when we need it
-
Weeplow® Venus 5.6L at c.£175-£225
-
The Phoenix Gravity 6L Water Filter with stand at c.£200-£300
-
The Ultimate British Berkefeld Starter Bundle 6L with stand and fluoride filters at c.£275-£375
These filters all are designed to look aesthetically pleasing, all work in basically the same way as in they filter water through terracotta/clay, sawdust/activated carbon and/or colloidal silver or they are just big metal water containers that just use big activated carbon filters. What needs clearly stating is that none of them recommend using anything other than potable water – if you’re using grey water then it may ruin the filter permanently, but this is an emergency if you’re running out of water! The main thing to remember is that you should only drink the filtered water as a really last resort, if death is the only alternative, as it can cause you all sorts of problems. Filter grey water purely to use as grey water for cooking and cleaning. You will probably have to throw the filter away afterwards but you will have survived.
If you are going to drink anything which you think has even the slightest chance of being of dubious quality. Remember to look and smell before you taste. If any of your senses sense something not 100% don’t drink it. With all water and we even include water out if the taps as this may become contaminated in an emergency, you may wish to improve your safety by sterilising it. There are three basic methods:
-
Boil your water. Keep a rolling boil for about 2 minutes. Then let call down. This will allow the water aerate and taste better. The issue here is that you will have to use your valuable fuel for cooking.
-
Use chlorine dioxide water purification tablets such as Oasis 67mg Water Purification Tablets 200 Tablets at c.£7-£9 or Aqua Tabs Water Purification Tablets 8.5mg x 100 at c.£11-£15. Just add a tablet to the amount of water on the instructions and leave for 30 minutes then it will be safe to drink.
-
At a real push, you can use household bleach, but only if it is unscented and contains no thickening agents (which is rare in the UK). Dosage: 1/8 teaspoon per 4.5 litres (1 UK gallon).Wait Time: 30 minutes minimum. If the water is very cold or cloudy, wait 60 minutes
-
If you read our article, ‘Hygiene is everything with Slightly Anxious’ you will find out how to wash and clean and how to go to the toilet while using the minimal amount of water. These techniques will hopefully prevent you having to extreme measures to keep hydrated.
Storing water in the garden
However, we have saved for last, our top tips for storing both potable and grey water if you are fortunate enough to have some outside space such as a balcony or better still a garden. This is using water butts and decorative planters.
Water butts are used to collect rainwater. This can be a valuable source of grey water. Rainwater is not drinkable. Yes the water is great when it comes from the clouds but as soon as it falls through the atmosphere it picks up all the pollution and then it hits our dirty roofs and gutters before being channelled into our great big butts (sorry I couldn’t help myself!). The advantage of having a supply of rainwater collected in a butt is that this is a supply of water for washing and cleaning (after filtering/sterilising) that you don’t have to use for potable water for. Some examples are:
These all include the kit you need to redirect rainwater from a drainpipe. Installing one, which you should be able to do yourself, means that you not only have an emergency supply of greywater but you can also use it to water your plants with if you attach a hose to the tap/spigot. Fortunately, in the UK we have a regular supply of rain so ensuring you have a an emergency supply shouldn’t be a problem.
Decorative planters are a great way of hiding potable water. They come in many shapes and sizes, the ones we’re after are basically water butts that have been disguised as planters, they are more architectural in design and allow for you to have a plant sitting on its top in its own container. Below this is storage for rainwater, but we suggest that you use it for potable water and fill the planter (or its liner) from the tap using a hose. Some examples are:
-
275L Noblesse Decorative Water Butt Flat Backed at c.£225-£300
-
360L Antique Terracotta Amphora Water Butt at c.£500-£700
There are hundreds of options, they all tend to be made from plastic and coloured and textured. Ones made of polyethylene (PE) are more potable friendly but we don’t think that’s good enough. Being outside and made for rainwater is not 100% hygienic. So you have two options; insert a flexible liner/bladder tank or insert a slimline potable tank. The flexible liner or bladder for potable water is like a very strong plastic bag for drinking water, it is often found on boats as its flexible form lets it fit into the nooks and crannies of a vessel. They don’t come in large sizes due to them being meant for small boats, but you could stack them in your planter and just remove them in an emergency. Examples are:
-
TPU Water Storage Bladder, 60 Gallon (272 litres) at c.£140-£180
-
Plastimo Flexible Water Tank 150 litres at c.£90-£130
-
Nuova Rade Flexible Water Tank 150L at c.£70-£90
-
Foldable Water Bladder, 100 Gallons (454 litres) at c.£70-£90
The other option is just to put a rigid potable water tank inside your decorative planter/water butt. The issue is that you will need to do some slightly complicated calculations as to which potable container will fit into which decorative planter/water butt, we have made some attempts on the website. Some examples are:
-
105 Litre Tower Potable Water Tank at c.£130-£170
-
Enduramaxx 500 Litre Slimline Potable Water Tank at c.£200-£250
There are two things you must remember, the decorative planter/water butt you are using as a disguise for your rigid or flexible water tank is not built for potable water so don’t use it as such and by this don’t use its tap/spigot or take water from it that isn’t from the potable container, unless its for grey water. Secondly, as stated previously, the water in plastic containers eventually goes off due to the plastic. So first you should sterilise it using the sterilisation tablets listed above or using these: Katadyn Micropur Forte MF 1T DCCNa (100 Tablets) at c.£25-£35. Then you might want to consider either running the water through one of the sterilisers listed above or boiling it before use. If you’ve stored it for six month, use it to water your plants and get some fresh tap water.
If money is no object
We have mentioned boats, so if you really want to push one out, there is always the option, if you have a garden and cash to burn, of having and underground potable water tank. A 3000 litre (they come in big sizes) tank will cost you a mere £1500 but the cost of getting a hole dug and the tank installed turns this into a mega project. Estimates are that a basic setup with no fancy plumbing is approx. £4,000 – £6,500 while a more complete system including a pump, filtration with proper integration will be £6,000 – £9,000. The cost of a decent second hand car but you would have the basic requirement for water for a family of six people for over three weeks!
Your to do list is:
1. Work out your target: 10 litres x people x 7 days
2. Choose a storage method that fits your space
3. Store bottles off concrete floors, on a shelf or pallet
4. Rotate stock: first in, first out, every 6 months
5. Buy purification tablets and know how to boil water safely
6. Fit a water butt if you have outside space
The bottom line
Storing drinking water is probably the most problematic of all the emergency preparation tasks. It is also one of the most critical, as without water we are in serious difficulty of a critical nature. The problem for us at Slightly Anxious is there is no simple option to recommend as its so dependent on your own individual circumstances. The people with the most space and biggest budgets will do the best but there is scope for those in more straitened/normal circumstances. Bottled water is not really that expensive when you compare the cost of storage containers, the issue is – where to store it! We will be posting on the website updates when we find new and innovative ways of storing water and are planning to hold a competition for our members on the novel ways they have found.
Remember, keep calm and visit us here.
