About 500 houses in the Tibohine and Ballaghadereen areas are without water, due to a burst water main on the North Roscommon Water Supply.
The burst occurred on the Old Dublin Road in Ballaghadereen, and Irish Water says about 500 houses are impacted in Tibohine, Lissacurkia and Lung.
It's expected repairs will be completed by this evening, and customers should have a full water supply restored by about 10 o'clock tonight.
Meanwhile, the water supply in Glenamaddy is returning to normal, following overnight restrictions on the scheme due to persistent heavy rainfall.
The restrictions were imposed last night for residents and businesses on the Glenamaddy Public Water Supply.
Irish Water has confirmed this afternoon that the supply is returning to normal.