Irish Water says it could be the weekend before boil water notices, which are in place for Kerry water supplies, are lifted.
Almost 3,000 customers are affected by boil water notices for the Caragh Lake, Annascaul, Aughacasla, Bonane and Dawros water supply schemes.
These notices were put in place due to power outages caused during Storm Barra.
Treatment plants rely on power to operate and not all have back-up generators; deluges of rain also resulted in poor quality water washing into plants.
Irish Water Operations Lead, Ian O'Mahony says it will take time to ensure water is properly disinfected:
There is still a disruption to the water supply for customers in Ceann Trá, Baile an Fheirtéaraigh and surrounding areas due to ESB outages caused by Storm Barra.
Irish Water says works are continuing to restore supply as quickly as possible to all affected areas.
