A Boil Water Notice in effect locally has been extended to include Carlow Town.
Irish Water says that 35,278 people are now affected by the unexplained pollution incident in the River Slaney on Wednesday evening.
It now covers Carlow Town, Tinryland, Nurney, Kernanstown, Ballyloo, Palatine, Killerig/Grange, Rathvilly, Tullow, Ardattin, Ballon, Rathoe, Bennekerry, Tankardstown, as well as neighbouring parts of Kildare and Wicklow.
The Utility is insisting that the water is safe once it’s been boiled and cooled.
Irish Water’s Jim Fitzgerald says they’ve tested the water to make sure there’s no other dangerous substances in it.
But he says the treatment plants in Tullow and Rathvilly simply can’t be guaranteed for drinking water at the moment.