A chlorine booster failure at the plant, which serves over 65,000 people, means that adequate chlorine may not have been reached in order to ensure that the water is safe to drink.
Irish Water and Wicklow County Council released the boil water notice today at 3pm, following advice from the Health Service Executive (HSE).
The areas affected are: Ashford, Newcastle including Newcastle Hospital., Newtownmountkennedy, Kilcoole, Kilquade, Kilpedder, Kilmacanogue including Glenview Hotel/Kilmurray Cottages, Greystones, Cookstown Road, Fassaroe/Berryfield Lane, Kilcroney, Delgany and Bray.
Make ice from cooled boiled water.
Domestic water filters will not render water safe to drink Caution should be taken when bathing children to ensure that they do not swallow the bathing water Prepare infant feeds with water that has been brought to the boil once and cooled.
If bottled water is used for the preparation of infant feeds it should be boiled once and cooled.
If you are using bottled water for preparing baby food, be aware that some natural mineral water may have high sodium content.
Check the label on the bottled water to make sure the sodium or `Na’ is not greater than 200mg per litre.
"In the meantime, all customers of this supply are advised to boil water before use until further notice.
"We will continue to work closely with Wicklow County Council, Dun Laoghaire Rathdown and Dublin City Council who run the plant on behalf of Irish Water and the HSE to monitor the supply and lift the notice as quickly as possible.