Water shortages will remain "one of the big issues" for emergency management for weeks to come, the National Emergency Coordination Group (NECG) said on Wednesday.
The most recent figures released show there are just over 15,000 people without water and a further 29,000 whose supply is restricted following the freezing conditions of Storm Emma.
“While there has been some recovery, there remains a long way to go but the pressure reductions are having a good effect,” the NECG said.
Delays are expected in refilling reservoirs as repairs to burst and leaking pipes continue. Local authority crews and “specialist leak detection units” have been mobilised across Dublin.
In a statement Irish Water said Storm Emma's severe impact on the national network saw extreme cold damage water treatment plants and burst a significant number of pipes.
In Dublin the condition of leaking pipes, which are an average 80 years old, together with increased demand, has forced authorities to reduce pressure overnight to allow reservoirs refill.
Irish Water said leaks “will require a sustained program of work over weeks and months to reach pre Storm Emma levels”.
The agency said it was concerned by reports that some areas were completely without water, including Rathmines, Rathgar and Milltown in south Dublin.
“Persistent problems with water supply in these areas suggest that there are significant leaks in the area and leak detection and repair crews have been dispatched as a matter of urgency,” it said.
Water supplies were curtailed in and around Dublin between 8pm on Tuesday and 6am on Wednesday.
Irish Water had said most of the 1.2 million people on the network in the capital and surrounding counties have seen little effect to their supply.
“Those on the edges of the network or on high ground are most affected,” a spokeswoman said.
The utility has been bombarded with complaints from customers living in Dublin who say their water supply has not returned or took hours to return.
Outside Dublin, supply was lost in areas of counties Tipperary, Galway, Wexford and Leitrim. There were restrictions in counties Leitrim, Meath, Galway, Mayo and Cork.
In Co Tipperary, about 12,000 people were left without water due to contamination of the source supplying the Fethard Public Water Supply by kerosene. Irish Water is providing water tankers in these areas.
In its status update, the NECG said conditions were improving with rain expected to move over the country on Friday and into Saturday. A gradual thaw has also led to better road conditions, it said. ESB Networks had restored all power outages by Monday.
Transport, which had also been crippled during the worst of the storm, has all but returned to normal. All motorways and national roads are open and public transport services are operating with just a “small number of diversions or curtailments”.
However, Irish Rail said its line from Gorey to Arklow will remain closed this week due to a landslide.
Health services have widely recovered too, despite predictions of a surge in emergency department activity in the aftermath of the storm.
For hospital services, all outpatient departments are open but only urgent inpatient elective cases will proceed this week. The situation is being reviewed on a daily basis, the NECG said.
Meanwhile, the Government has reiterated its intention to fund local authorities for exceptional and unbudgeted costs incurred during the “severe weather emergency events”.