Homeowners and business owners in north Dublin are being asked to conserve water amid a surge in demand due to the warm weather.
Irish Water says people in areas including Garristown, Ballymadun and Palmerstown can expect low pressure or outages until later this morning.
Parts of Laois, Donegal and Kerry are also impacted.
Here in Dublin, the utility says it is working with Fingal County Council to restore supplies to normal levels.
Tom Cuddihy from Irish Water's appealing to people to only use water for what's necessary.
He said, "avoid extended showers and having taps running when brushing teeth or rinsing vegetables and so on."
He added that people should also be mindful of their water usage in the garden.
"Don't water lawns, it's no harm to let the grass get a bit of a tan this time of year, it will recover very quickly."
