Can you drink the tap water at home without letting it run first? How long should you let the tap water run before drinking it? How can we avoid wasting water by letting it run?
Even if your local water provider claims that the water is drinkable it may not be safe to drink due to local pipe contaminants. Tap water can contain various contaminants, such as bacteria, lead, nickel, and other metals, that can pose health risks if ingested in high amounts. Therefore, it is important to know how to properly treat your tap water before drinking it or using it for cooking.
Here are some tips on how long you should let your water run before drinking it, why it matters and what the alternatives are if you want to save water.
Why you should let your tap water run?
The main reason to let your water run before drinking it is to flush out the pipes and faucets that may have accumulated harmful substances over time. These substances can leach into the water from the plumbing materials, especially if the water has been sitting in the pipes for a long time, such as overnight or during periods of low use.
One of the most concerning contaminants in tap water is lead, a highly poisonous metal that can damage the brain, kidneys, and nervous system, especially in children and pregnant women. Lead can enter the water from old lead pipes, solder, or fixtures that are still present in some homes and buildings, especially those built before 1986 in the US and between the 1970s and 2013 in Europe (see year by country in the sources section). According to the Environmental Protection Agency (EPA) in the US, there is no safe level of lead in drinking water, and the only way to eliminate it is to replace the lead service lines and plumbing components. Source: Running and hydration: Everything you need to know - Runner's World.
Another metal that can be found in tap water is nickel, an element that is not useful for the body and can be toxic if ingested in high doses. Nickel can also cause allergic reactions in some people, such as skin rashes, itching, and swelling. Nickel can come from the corrosion of stainless steel pipes and faucets, or from the natural deposits in the soil and rocks. Source: How long should you run tap water before drinking it? - AS USA.
Other possible contaminants in tap water include bacteria, viruses, parasites, pesticides, herbicides, nitrates, chlorine, fluoride, and pharmaceuticals. These can vary depending on the source and quality of the water, the treatment methods used by the water utility, and the condition of the distribution system.
Some of these contaminants can cause gastrointestinal illnesses, infections, or chronic diseases. Therefore, it is advisable to check the water quality report from your water provider, or to test your water yourself, to know what is in your tap water and how to treat it accordingly.
Read more in our guide about how to choose the right water filter.
How long you should let your tap water run?
The amount of time you should let your water run before drinking it depends on several factors, such as the type and length of your service line, the age and condition of your plumbing, the water usage in your household, and the temperature and pressure of the water. There is no universal rule that applies to all situations, but here are some general guidelines from the EPA and other sources:
1. If you have lead pipes (service line), or you are not sure what kind of pipes you have, you should let the water run for 3 to 5 minutes before using it for drinking or cooking. This will help to flush out the water that has been in contact with the lead pipes for a long time.
2. If you do not have lead pipes, but you have lead solder or fixtures in your plumbing (for example an old faucet), you should let the water run for 30 to 60 seconds before using it for drinking or cooking. This will help to flush out the water that has been sitting in the faucets or the pipes near the faucet. Source: Let it run ... and get the lead out! - MN Dept. of Health. .
3. If you do not have any lead in your service line or plumbing, but you have other metals or contaminants in your water, you should let the water run until it feels cold (although this may not work in warmer regions). This will help to flush out the water that has been warmed up by the pipes or the environment, and may have higher levels of metals or bacteria. Source: Is Tap Water Safe To Drink? - Cleveland Clinic Health Essentials.
4. If you need to boil water for any reason, such as for making tea, coffee, or baby formula, you should always use cold water from the tap, and not hot water. Hot water can dissolve more lead, nickel, or other metals from the pipes, and may also have more bacteria or other contaminants. Boiling water will kill most of the germs, but it will not remove the metals or chemicals.
5. Everyone should let the water run for at least 10-30 seconds unless you have a water filter installed on the faucet. Read more below.
How to avoid letting the tap water run and wasting water
With water drought and shortages around the world we should avoid wasting water if possible. Letting the water run is obviously a waste but you could try to use the first water for plants or cleaning for example.
If you want avoid wasting water the simples way to improve tap water quality and make it safer and more enjoyable is to use a high quality water filter. A water filter can remove or reduce many of the contaminants in your tap water, such as lead, nickel, chlorine, bacteria and pesticides.
There are different types of water filters available, such as filter jugs, faucet filters, under-sink filters, or whole-house filters. You should choose a filter that is tested and certified by a reputable organization, and that meets your specific needs and budget. Always follow the manufacturer's instructions on how to install, use, and maintain the filter, and replace the filter cartridges regularly.
With a faucet filter installed it's sufficient to let the water run for about 5-10 seconds to flush pout the filter. If you have been out of the house for half a day or more then let it flush for 20-30 seconds.
Read more about EcoPro by Tappwater.
Source: How long should you let water run before drinking?
Conclusion about how long to let tap water run
Drinking enough water is vital for your health and well-being, but not all water is equally safe and pure. Tap water can contain various contaminants that can affect your water quality and pose health risks. Therefore, it is important to know how to treat your tap water before drinking it or using it for cooking.
One of the simplest and most effective ways to do so is to let your water run for a certain amount of time, depending on your service line and plumbing conditions. This will help to flush out the pipes and faucets that may have accumulated harmful substances over time. The problem of course is that this will waste a lot of water.
To reduce water wastage use a high quality water filter. This way you will waste less water and always have access to tasty and safe drinking water at an instant.
By following these tips, you can ensure that you and your family have access to clean and healthy water every day.
Additional information
When was lead pipes banned by country in Europe?
The use of lead in water pipes has been banned or restricted in many European countries, but the exact dates and regulations vary by country. Here is a summary of some of the countries that have implemented bans or limits on lead in water pipes:
United Kingdom: The use of lead pipes has been banned since the 1970s¹.
Germany: A new law was instituted in December 2013 to regulate lead levels in drinking water pipes not to exceed 10 µg/L. However, many old buildings are still affected by contaminated pipes, and many people are not aware of the problem².
France: Lead pipes were banned in 1995, and the maximum allowable concentration of lead in drinking water was lowered to 10 µg/L in 2014³.
Spain: Lead pipes were banned in 2004, and the exposure level was lowered to 10 µg/L in 2013⁴.
Italy: Lead pipes were banned in 1988, and the exposure level was lowered to 10 µg/L in 2013⁵.
Sweden: Lead pipes were banned in 1986, and the exposure level was lowered to 10 µg/L in 2013.
Denmark: Lead pipes were banned in 1977, and the exposure level was lowered to 10 µg/L in 2013.
Finland: Lead pipes were banned in 1994, and the exposure level was lowered to 10 µg/L in 2013.
Norway: Lead pipes were banned in 1980, and the exposure level was lowered to 10 µg/L in 2013.
These are some of the examples of the countries that have taken measures to reduce or eliminate the use of lead in water pipes. However, there may still be some lead service lines or plumbing components in older buildings that have not been replaced or tested. Therefore, it is advisable to check the water quality report from your water provider, or to test your water yourself, to know if there is any lead contamination in your tap water.
Sources for when lead pipes were banned:
(1) Lead service line - Wikipedia. https://en.wikipedia.org/wiki/Lead_service_line.
(2) Lead - ECHA. https://echa.europa.eu/hot-topics/lead.
(3) Are lead water pipes still a problem in the UK?. https://thewaterprofessor.com/blogs/articles/lead-pipes.
(4) 6.6. Lead (Pb) — European Environment Agency. https://www.eea.europa.eu/publications/2-9167-057-X/page023.html.
(5) An Update on the ‘Lead-Free by 2014’ Mandate – Europe. https://www.thermofisher.com/blog/metals/an-update-on-the-lead-free-by-2014-mandate-europe/.
