Tap water FAQs
Answers to some of the more common questions about tap water and hydration are listed below.
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Absolutely. Staying hydrated is important for feeling energized and concentrated. Our bodies are on average 60% water and maintaining a water balance is absolutely vital for our health and survival. Opting for plain water rather than sugary drinks also contributes to overall fitness as it hydrates the body and mind without unnecessary calories. Tap water is of highest quality in the UK and given its wide availability, it offers an ideal daily choice for a healthy lifestyle.
Healthy adults can let thirst be their guide because thirst is the organism's primary feedback mechanism for avoiding dehydration. However, this mechanism is weakened in children and the elderly and cannot be relied upon completely.
In order to stay hydrated, one's intake of fluids must match their outputs. How much that exactly is depends on your body constitution, age, sex, physical activity levels, and also on environmental conditions such as temperature and humidity. The adequate daily fluid intakes as set by the European Food Safety Authority and by the NHS vary between 1.6-2.5l a day. These volumes apply to conditions of moderate environmental temperature and moderate physical activity and ought to be consumed throughout the day.
For the sole purpose of hydration, there is no qualitative difference between plain water and water from foods and other beverages. According to the Annual Review on Nutrition, food and metabolic oxidation can in fact cover up to 20-40% of the daily fluid intake. Yet when compared to many other beverages, water has the advantage of being sugar-free. The Scientific Advisory Committee on Nutrition has recently recommended that consumption of sugar-sweetened drinks should be minimised by both adults and children.
Scientists warn that fluid deficits of more than 1% decrease exercise performance, thermoregulation, and appetite, and blunt baroreceptor control. With fluid losses of 4% and more severe performance drops are observed as well as difficulties in concentration, headaches, irritability and sleepiness, cardiovascular function impairment, increases in body temperature, in respiratory rates, and in heart rate. Researchers add that the effects are more pronounced when heat stress is added.
Dehydration of more than 10% at high ambient temperatures is a serious risk for a life-threatening heat stroke with elevated body temperature, inadequate cardiac output leading to reduced perfusion of tissues and eventually to rhabdomyolysis and organ failure.
Chronic dehydration can increase the risk of infection, especially of the urinary tract. EFSA elaborate on dehydration symptoms in their 2010 study.
Young children and adolescents particularly are at risk of impaired cognitive function (concentration, alertness and short-term memory) due to insufficient hydration. The elderly are at special risk of too low water intakes due to loss of thirst sensation and appetite, and to a reduced capacity of their kidneys to concentrate the urine.
Thirst and dry lips are one indicator of dehydration. Urine colour is often considered another one but researchers say it does not show a precise correlation with hydration status and is, moreover, dependent on dietary factors and medications.
Yes, British tap water is perfectly trustworthy. It's also largely popular: 94% of the population are satisfied with their water supply. We are constantly working to further improve these figures and please even those who have still been sceptical.
Millions of tests are conducted annually to guarantee the best possible quality of water for consumers. That makes tap water the most supervised drink out there. The standards are taken from European legislation, which is mainly based on WHO state-the-art science.
As a public supply service, the water industry does its best to achieve outstanding quality as well as transparency. As a result, you can view your region's latest quality results online. Below are links to webpages on quality of individual water companies.
NB: you can use our Find your supplier tool in case you are not sure who your supplier is.
- Affinity Water
- Albion Water
- Anglian Water
- Bournemouth Water
- Bristol Water
- Cambridge Water
- Dee Valley Water
- Dŵr Cymru - Welsh Water
- Essex & Suffolk Water
- Northern Ireland Water
- Northumbrian Water
- Portsmouth Water
- Scottish Water
- South East Water
- South Staffs Water
- South West Water
- Southern Water
- Sutton and East Surrey Water
- Thames Water
- United Utilities
- Wessex Water
- Yorkshire Water
Tap water is the freshest drink you can quench your thirst with, unless you have a safe well or spring of your own of course! It takes anywhere from a few hours to a few days to get it from the treatment plant to your home.
Tap water is a great basis for homemade drinks. You can give it a quick twist by simply adding a few leaves of mint and a few slices of citrus fruits. Flavoured ice cubes are a fun and aesthetic idea. Be creative (or ask Google, anyway).
If you are sensitive to chlorine and you do not like the smell or taste then a simple way to remedy the problem is to cool the tap water before using it for drinks.
If you have been away for two weeks or more, then the quality of water in your home may deteriorate. It is advisable to run your drinking water taps after prolonged periods of non-use. Remember to catch the running water and re-use it for jobs such as watering your plants!
It is interesting to note that water flavour is judged very differently by different people. The BBC carried out a blind-tasting experiment to resolve the north-south taste divide. See the conclusion for yourself.
In 2008, 13% of households surveyed by DWI admitted they boiled water as a preventive measure. That's a lot of wasted money and electricity. Unless your water company issues a specific boil notice, it is not necessary at all. See the FAQ "Can I trust tap water in the UK" above for more details on why you might want to reconsider your boiling habits.
By law your local water company has to supply wholesome water that is suitable for all domestic purposes, including drinking, cooking and washing. All public water supplies are regularly tested in England and Wales and the results which are published and available to every consumer on request show that tap water is safe to drink and there is no need to install additional treatment within the home as a health protection measure. The DWI gives more details on water filters here.
DWI advises that we do not use hot water or water from our bathroom taps for drinking or cooking because it usually comes from a storage tank in the loft and is not as fresh or as safe as water directly from the mains.
All tap water intended for human consumption supplied by water companies is subject to stringent standards, which make sure you can drink it on a daily basis without any harm. The latest results show 99.96% compliance rates for tap water in England and Wales, 99.89% for Scotland, and 99.86% for Northern Ireland.
Occasional failures are mostly attributable to poor tap hygiene or inappropriate plumbing arrangements. Microbiological failures in consumers' tap then contribute to failures of chemical standards and result in objectionable tastes and odours. You can read more about common plumbing issues and find your nearest plumber on WaterSafe. Have a look at our Looking after water in your home guidebook to find out how you can influence water hygiene.
Throughout history, epidemics of diseases such as cholera, dysentery, typhus, and hepatitis A killed tens of millions of people all over the world. It wasn't until the mid-19th century that scientists like John Snow and Filippo Pacini discovered that these mass-killers were waterborne diseases and measures could start to put an end to the suffering.
A major breakthrough in combating cholera and other waterborne diseases was securing water safety through disinfection. In 1897 the town of Maidstone, England was the first to have entire water supply treated with chlorine.
Nowadays, chlorine is a disinfectant used by the water industry worldwide to maintain hygienic conditions within the public water supply network of pipes. At the very low levels used in drinking water (routinely at 0.5 mg/l or less, whereas WHO sets the maximum guideline at 5mg/l) it is perfectly safe. The WHO further assures that any risks to health from chlorination by-products are extremely small in comparison with the risks associated with inadequate disinfection.
Yes, as long as it's compliant with the legal quality standards. According to a 2012 survey, babies under 12 months get 81% of their liquids (excluding breast milk) from tap water. Children aged 0-15 have 53% of their daily liquids covered by tap water.
NB: Anglian Water warns that domestic water softeners regenerated with brine produce water containing an increased concentration of sodium. Always use unsoftened mains water for drinking, cooking and for preparing babies' feeds.
Tap water away from home
In most cases the answer is yes. Tap water supplied by water companies to public buildings, such as schools, hospitals, restaurants, shops, sports facilities, cultural venues etc. is as fit to drink as the one in your home because it is subject to the same stringent quality requirements. Unless there is a "non-drinking water" sign or you judge the outlet as frowzy, you shouldn't worry about refilling your bottle in public buildings. Quenching thirst on the go is important for staying hydrated!
It is challenging to protect public drinking fountains from vandalism and contamination, but they have served the nation well for over 150 years. They are a convenient, cheap, and sustainable means of staying hydrated when out and about, especially in summer. No outbreaks of diseases caused by water from drinking fountains have been reported.
When drinking from a fountain, we recommend that you let the water flow for a few seconds first and that you refrain from touching the jet with your lips. Downward facing and protected jets are more hygienic than the upward bare ones.
Without a doubt. In a governmental attempt to combat binge drinking, establishments that sell alcohol have in fact been obliged to have free tap water for their customers. There is no need to feel uncomfortable about asking for tap water, it's become widespread: A 2015 survey by YouGov revealed that 53% of people aged 18-24 one third of older adults do drink tap water in cafes and restaurants. Why not get on board?
That varies with country of course. As a rule of thumb, EU countries, US, Canada, Australia, and Japan have safe drinking water. Many other countries have safe water in cities but not in rural areas. Please try to always take local advice in your destination.
Tap water in the UK
In 2014, water companies carried out over 4.5 million tests of our water for around 50 different chemical and microbiologal substances. Each of these has a standard, set by law, that must be met. Only 2100 of these 4.5 million failed to reach these standards. This puts public water supplies in the UK amongst some of the very best in the world.
About one third of tap water in England and Wales comes from underground sources (aquifers), in Northern Ireland and Scotland this figure is 6% and 3%, respectively. The rest comes from reservoirs, lakes, and rivers. Namely, surface water in the UK accounts for 68% and mixed sources for 4% of the supply.
The average cost of a litre of tap water in the UK is 0.1p, so you can stay hydrated all year long for less than £1.
For most consumers, water and sewerage charges are a relatively small proportion of their income. However, the same may not be true for households on low fixed incomes. The water industry is conscious of the impact rising bills may have on consumers, particularly those who can't easily afford their bills or are already struggling to pay. To help these customers, water companies provide practical help and advice. You can read more about affordability here.