Irish Water is working to restore the supply in the Kilcash area.
The reservoir interruption may also affect the surrounding areas.
Works have been in progress since 12pm today, August 31.
An alternative water supply will be available at the School Carpark and Cois Coille Housing Estate.
Members of the public must use their own containers to transport water to their homes.
Irish Water says they every effort is being made to sanitise the tanker, bowser, and dispensing tap.
However, they cannot guarantee that containers used by the public are adequately sanitised.
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