People have been urged to conserve water as there has been a significant number of bursts and leaks following the cold snap last week, according to Uisce Éireann.
Head of Water Operations Margaret Attridge made the appeal for action while the system is being restored.
"We have seen a notable increase in leaks and bursts over the weekend. And while we have been busy in repairing leaks, the increased demand is draining down some of our resevoirs. We have had to put in place some nighttime restrictions across the country," she told RTÉ's Morning Ireland.
"This is impacted overnight and [is affecting] around 16,000 people, mostly across the northern part of the country - Galway, Roscommon, south Leitrim, Meath and down into Kerry and Kilkenny also.
"We've also seen in the greater Dublin area the demand hit record levels over the weekend and 646,000,000 mililitres a day.
"That's higher than our water treatment plants have ever produced, and so our crews have been busy and our contractors are repairing leaks over the weekend."
We need your consent to load this rte-player contentWe use rte-player to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences
She added that most people who had no water last week should now have supply restored.
"That was mainly due to power outages. What we're seeing now, it's really due to the bursts and leaks, so outages should be of a short duration during the day."
Ms Attridge said that the public can find information on their own areas on the Uisce Éireann website. She also advised that people can register for a text alert system.
"We will be proactive in providing them updates, but we would ask people to continue to conserve water."
She said that the restrictions will depend on what can be done to protect the storage reservoirs. However, Ms Attridge added that some restrictions "will be in place most evenings throughout the week".
"Most households should have water in their attic tanks to keep them going through the night.
"Hopefully it'll have low impact on people, but the more we all work together on this, the quicker the recovery will be," she added.
