Uisce Éireann is investigating taste and odour issues with the Cleggan/Claddaghduff Public Water Supply.
However, the water authority says the supply continues to meet regulatory standards.
It says it's aware of a small number of homes contacting its customer care centre about intermittent taste and odour issues.
Uisce Éireann says it's treating this matter with the utmost priority, to ensure there's no impact on public health.
To date, all chemical and biological results are compliant with legislative requirements.
Additional sampling programmes are continuing, to include extensive network flushing.
Uisce Eireann is assuring householders that it will continue to test the water to determine the root cause of these issues.
It adds the water from the Cleggan/Claddaghduff supply is safe to drink once it is running clear.
