When would we issue a Boil Water Notice?

The most common reason for issuing a Boil Water Notice would be where routine testing of the drinking water supply has shown the presence of harmful bacteria (such as E. coli), or pathogens such as Cryptosporidium. The public health of our customers is of the utmost importance to Irish Water – therefore if such results are confirmed, we consult with the HSE to ensure an appropriate advisory notice is issued immediately.

In some cases a Boil Water Notice may be imposed where there is a risk of contamination but where test results are yet to be confirmed. An example might include where the disinfection system has failed, or where a pollution event has occurred in the vicinity of the source water. In these cases it is prudent to protect public health by issuing a Boil Water Notice rather than wait for test results to confirm the risk.

In these cases boiling the drinking water and cooling it will kill any harmful bacteria that may be present making it safe to drink.

Using water in a boil water notice

How to boil and store water safely

Boiling the drinking water by bringing it to a vigorous, rolling boil (e.g. with an automatic kettle) and allowing it to cool will kill any harmful bacteria and pathogens. It is advisable to fill a container with the boiled water, cover and store in a refrigerator or cold place. Great care should be taken with boiled water to avoid burns and scalds. Accidents can easily happen, especially with children.

N.B. Water from the hot tap is not safe to drink. Also, Irish Water cannot vouch for the ability of any domestic water filters to remove harmful bacteria – therefore it is advisable that water should be boiled even if these are in place.

What you should use cooled boiled water for

  • Drinking
  • Drinks made with water
  • Preparation of salads and similar foods, which are not cooked before eating
  • Brushing of teeth or gargling
  • Making ice - discard existing ice cubes and make ice from cooled boiled water
  • Filtered water - pour out any filtered water in fridges and use cooled boiled water

What you do not need cooled boiled water for

  • Personal hygiene, such as showering and bathing
  • Toilet flushing

Child and infant care during a boil water notice


If you are bathing children please ensure that they do not swallow the bath water.

Preparing feeds and baby bottles

Irish Water has received the following advice from the HSE on this matter:
Where a Boil Water Notice is in place, you can prepare infant formula from tap water that has been boiled once (rolling boil for 1 minute) and cooled beforehand. Bottled water can also be used to make up infant formula. All bottled water, with the exception of natural mineral water, is regulated  to the same standard as drinking water. It is best not to use bottled water labelled as ‘Natural Mineral Water’ as it can have high levels of sodium (salt) and other minerals, although it rarely does. ‘Natural Mineral Water’ can be used if no other water is available, for as short a time as possible, as it is important to keep babies hydrated.

If bottled water is used to make up infant formula it should be boiled once (rolling boil for 1 minute), and cooled in the normal way.

Ready-to-use formula that does not need added water can also be used.

Giving water to animals

Does water need to be boiled for pets?
To be on the safe side, it is a good idea to boil the water and let it cool before giving to your pet.

Can Livestock drink unboiled water?
A Boil Water Notice is imposed to protect human health. If you have concerns regarding your animals drinking water that is subject to a Boil Water Notice then you should consult your Vet. Outdoor animals, such as cattle and horses, are exposed to bacteria on a daily basis vastly in excess of that experienced by humans.

More information on your Boil Water Notice

Visit our Water Supply Updates map for detailed information and updates about Boil Water Notices. We also use leaflet drops to keep affected customers updated on the situation.

Concerned about the quality of your drinking water? Contact us on 1850 278 278. Lines open 24 hours a day, 7 days a week. Please note that the rates charged for 1850 numbers may vary across different service providers. Calls from mobiles may be more expensive.

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