Uisce Eireann says water supply is returning to customers in Ballyshannon, Bundoran, and surrounding areas.
It follows the completion of repairs to a burst on the trunk distribution main at Lough Melvin Water Treatment Plant, which had impacted the supply this morning.
The authority says it can take 2-3 hours for the normal water supply to return as water refills the network, particularly for those properties on high ground or at the end of the network.
Homes and businesses are being asked to be mindful of their water usage to allow supply to catch up with demand.
