Around 4,000 people are still without water in Co Kerry after a pump failed at Listowel.
Irish Water say supply is slowly returning to the affected water treatment plant.
The utility says repairs were successfully completed on one pump serving the Listowel Regional Water Treatment Plant on Sunday night.
Water is now being pumped to the plant, and Irish Water say it expects supply will return to homes and businesses in Listowel, Tarbet, Moyvane, Knockanure, Lisselton, Finuge, Lixnaw and surrounding areas during today.
Replacement parts for the pump made by EPS Group in Mallow, as engineers worked late into the night to carry out the repairs.
Senior officials from Irish Water and Kerry County Council say they will continue to monitor the situation closely.
"Work will continue on implementing a back-up pumping system so that we have the necessary resilience in place for securing the supply", Irish Water says.
"We will be implementing a full replacement of these pumps as part of an upgrade programme and the timing of this replacement is being reviewed by Irish Water following this incident", it adds.
Water tankers will continue to available at the following locations on Monday until full service is restored:
- Listowel - The Square and car park at Kerry County Council offices
- Lisselton - Car park at Lisselton Cross
- Lixnaw - Church car park
- Knockanure - Church car park
- Finuge - Car park at GAA grounds
- Moyvane - Church car park
Customers who currently have a supply are also being asked to continue to conserve their supply.