Dubliners are facing night-time water restrictions for the forseeable future as the fallout from Storm Emma continues.
Irish Water was forced to restrict the supply to 1.2 million people across Dublin and parts of Meath, Kildare and Wicklow overnight, while 33,500 more are cut off in other counties.
The problem prompted the imposition of a 12-hour restriction across the Greater Dublin area from 7pm to 7am.
This will result in reduced water pressure during these times.
"This is essential to allow our reservoirs to refill as repairs to bursts and leaks are under way," said Irish Water.
It said the problems are likely to continue for a number of days and possibly weeks.
"Irish Water recognises that many of our customers continue to face severe impacts from water interruption or restrictions, where customers only have water at certain times," it said.
These are likely to continue for "a number of days", but it could be longer in the Greater Dublin area, where demand increased by 10pc over the weekend.
"Despite having our plants working at peak output, storage of water in the reservoirs was significantly depleted," Irish Water said.
"Demand is continuing to rise and our reservoir levels continue to drop. There is not enough water in our reservoirs to meet the current levels of demand.
Hospitals on the network will be prioritised and have water diverted to them.
The utility added that outages could be reported by calling 1850 278278 and that advice was at water.ie.
Irish Water managing director Jerry Grant painted a gloomy picture of night-time restrictions running into weeks or months as it struggles to repair the ageing infrastructure.
In Dublin, the situation was compounded by the loss of 30 million litres of potential supply from the Vartry Plant in Wicklow due to an algae bloom.
"It's a very difficult position," Mr Grant told the Herald.
"We won't know until we get out on the ground how long the battle will be. My sense is we're talking weeks, if not months.
"We believe cast iron pipes are fracturing due to small ground movements and the bursts are happening gradually.
"We're used to managing Dublin on tight margins. The new supply is vitally urgent, I cannot overstate that."
Among the worst-affected counties with no supply is Wexford, where 17,500 are affected. The trunk mains serving Wexford town was damaged by a fallen tree and repair crews had to traverse more than a metre of snow into a wooded area to make repairs.
Around 2,000 customers in Cork, 12,250 in Tipperary and 2,000 in Limerick have no water.
Those on restricted supply number 48,000 across Cork, Galway, Kerry, Laois, Leitrim, Longford, Mayo, Meath, Waterford and Westmeath.
In addition, nearly 3,000 people are on storm-related boil water notices, mostly in Aughrim, Co Wicklow.