Two Do Not Consume notices in place for parts of Cavan and Monaghan have been lifted.
Irish Water this afternoon said the notices in Cootehill and Newbliss have been lifted with immediate effect.
The notices were put in place due to elevated levels of manganese in both supplies.
Almost 2,200 people in Cootehill and over 400 in Newbliss were affected as the notice meant alternative water supplies had to be used.
Irish Water today said it was lifting both notices after consultation with the HSE and both County Councils.
In statements to Northern Sound News, it said people can "now resume normal use of the water supply for drinking, food preparation and brushing teeth".
It's apologised to the people affected.