A boil water notice has been issued for 1,500 people in Co Westmeath.
It affects households who are served by the Castlepollard high level public water supply, and will remain in place until further notice.
The areas affected are Ballymanus, Hilltown, Slieveboy, Loughpark, Fore, Martinstown, Glenidan, Cummerstown, Collinstown, Ranahan and surrounding areas.
The advisory has been put in place as a precaution after a mechanical issue at the plant.
The mechanical issue resulted in the disinfection process being compromised.