Update 8.40pm: Water supplies are to be restricted in some areas at night in response to severe pressure on treatment plants following Storm Emma.
Burst pipes and people leaving taps on to avoid freezing as well as increased demand has depleted supplies after some of the worst blizzards to hit the country for decades.
The full list of water restrictions can be found here.
Around 18,000 people have run dry, mostly in Wexford in the South East, and thousands more already face curbs on use, Irish Water said.
The Greater Dublin area saw an increase in demand of over 10% from Friday to today.
Excessive water usage being registered across Galway City and County. Restrictions in place over night on several schemes. Great work being done by @GalwaCoCo and @GalwayCityCo Full details at https://t.co/g6A5ly1Coe #StormEmma— Irish Water (@IrishWater) March 4, 2018
A statement from the National Emergency Coordination Group said: "Our main concern today is the increase in demand across the country which is putting severe pressure on our water treatment plants.
"Despite having plants working at peak output, storage was depleted by 30 million litres.
"Similar pressures are occurring elsewhere and if not reversed will lead to pressure reductions and the possibility of night-time restrictions."
Irish Water is reporting about 18,000 people are without water, of which over 11,000 are in Wexford. Currently, 66,000 people have restricted supply.
The Group added: "Householders are urged to conserve water. In addition, the public is asked to visit premises which have been unattended over recent days to check for running taps and burst pipes."
The organisation's chairman Sean Hogan said it would not be a normal Monday in many areas and urged employers and employees to consider staggering opening and start times to reduce peak volumes of commuter traffic as well as options for working from home.
Storm Emma: here's a look back on the memorable week that was... pic.twitter.com/wmsZncig2R— RTÉ News (@rtenews) March 4, 2018
Earlier: HSE expects increased waiting times at emergency departments as weather slows discharge of patients
Update 6pm: The HSE said it is expecting increased waiting times in emergency departments over the coming days.
Due to the heavy snowfall and travel conditions, it has not been possible to discharge all patients who were ready to leave hospital.
"We hope patients and their families understand the reasons for this and we will endeavour to facilitate their discharge as soon as possible this week," the HSE stated.
It is anticipated that over the coming week, as patients are gradually discharged, coupled with an expected increase in emergency department attendances, there will be delays in admissions.
The HSE is asking people to consider using one of the Minor Injury Units rather than present at A&E departments.
Day surgery will proceed in some acute hospitals from tomorrow.
The HSE has cancelled all non-urgent surgeries planned for Monday - hospitals will be in touch over the coming weeks to reschedule their appointments.
Non-urgent surgeries planned for Tuesday will be reviewed on tomorrow, and the HSE will make an announcement then regarding the remainder of the week.
Outpatient appointments will recommence across all hospitals tomorrow, with the exception of Wexford General.
With HSE services in Cork and Kerry returning to normal, the HSE would like to thank the public for its support and understanding during the recent severe weather. Read the full Joint statement from HSE services in Cork and Kerry.https://t.co/9VkgRfxDac pic.twitter.com/rZhkmemMJx— HSE Ireland (@HSELive) March 4, 2018
Earlier: Transport services to resume on majority of routes
Iarnród Éireann has said that full services will be resuming on the vast majority of routes.
Today, services are operating on all routes this evening , except:
Rail services are operating on all routes tomorrow, except Limerick to Ballybrophy via Nenagh & Waterford to Limerick Junction. It is hoped that they will resume on Monday evening, and bus transfers will operate in the meantime.
All routes are expected to be up and running by Tuesday.
Bus Éireann said that school transport services will resume tomorrow morning "dependent on local road conditions and possible school closures".
"Given the ongoing Status Orange warning in some areas until noon tomorrow, there is likely to be disruption, particularly in parts of the East, South and Southeast," a Bus Éireann statement read.
"Bus Éireann continue to monitor the situation and are making every effort to ensure as many school transport services as possible operate, where the school is open and it’s safe to do so."
The Luas Green Line is operating from Sandyford to Broombridge in both directions. Upper O’Connell to Broombridge has been opened. There is no service between Sandyford and Bridesglen.
The Red Line is running between The Point and Red Cow, but there are no services between Red Cow and Tallaght/Saggart. Connolly Luas stop remains closed.
Luas staff working really hard to clear snow left by #StormEmma near Tallaght Hospital on the Red Line.March 4, 2018
Dublin Bus said that is expecting a full service, with Real Time Passenger Information, will operate tomorrow, with some curtailments in place.
"We advise customers to expect delays in the morning and allow extra time for their journey especially at peak times, as traffic will be heavy with schools and workplaces reopening," the company stated.
Gardaí are currently conducting rolling road closures between Junction 10 and Junction 9 of the M7 to facilitate the clearing of snow.
Earlier: Fears that accumulations of melt water could lead to localised flooding
Update 4.57pm: The Office of Public Works is continuing to monitor sea and river levels, as melting snow increases the risk of flooding.
CEO of Laois County Council John Mulholland says local authorities are carrying out risk assessments:
"We've heeded very much the warning provided by the OPW," he said.
"There are risk assessments going on in Local Authorities, wherever it is applicable, and action plans will be put in place to deal with any consequences such as the procurement of sandbags and warning residents as regards the state of alert."
Local authorities are monitoring and the public are advised to closely monitor river levels at over the coming days and during the period of snow melt, especially in smaller, steep and mountainous catchments that have experienced heavy snowfalls. #stormemma https://t.co/xUWrloYIO8— MerrionStreet.ie (@merrionstreet) March 4, 2018
Met Éireann said: "Lying snow and ice will lead to continued hazardous conditions and melting will lead to localised spot flooding, but the general trend is for improving conditions.
"Highest temperatures three to six degrees."
Gardaí have reported flooding in Cork.
River levels are rising due to snow melt and rainfall. We are asking members of public & farmers to stay away from rivers and watercourses for the coming days, as river levels are expected to rise further #stormemma pic.twitter.com/RpQ4CLq45x— Cork County Council (@Corkcoco) March 4, 2018
Irish Water is appealing to all customers to conserve water amid unprecedented demand due to people leaving taps running during the freezing weather. It caused reservoir levels to drop.
Update - 3.12pm: It looks like third-level institutions will be open tomorrow as the thaw continues after the 'Beast from the East'.
University College Cork have said that it will be business-as-usual tomorrow as classes will resume at the University.
However, they said for those who have to travel some distance, "safety is paramount, and you should make a judgement call as to the advisability of travel".
Waterford Institute of Technology have said that all their campuses will open as normal tomorrow with lectures scheduled to commence from 11.15am onwards.
The campus in Maynooth will also re-open tomorrow, but they have advised staff and students not to take unnecessary risks in travelling.
2.57pm: Wexford, West Wicklow and North Kildare have been highlighted as areas that have been worst affected by the snow.
An update of the National Emergency Coordination Group has taken place, with the message that tomorrow will not be a case of back to normality.
It is thought a number of schools in the affected areas will close, with decisions to be taken on a case-by-case basis.
Chair of the National Emergency Coordination Group, Sean Hogan said: "Schools in areas where it is feasible have been checking their premises today and linking with school bus operators in order to make decisions about opening tomorrow.
"This has been done a case-by-case basis and decisions will be communicated to parents in each case.
"However, from the reports we have it seems very unlikely to us that in the conditions we have in the areas worst affected, such as Wexford, West Wicklow and North Kildare, that it will be possible for schools to open."
Elsewhere, outpatient clinics, as well as elective and routine procedures, will go ahead as planned at the three children's hospitals tomorrow.
However, there may continue to be an impact on some services into early next week.
Patients who had appointments cancelled last week will be contacted by the relevant hospital directly to reschedule their appointment.
In a joint statement, the hospitals thanked their staff for their efforts during the recent cold snap.
12.50pm: Transdev have issued an update on the Luas service in Dublin.
They say the Luas Green Line service between Sandyford and Broombridge is operating in both directions, but there is no service between Sandyford and Brides Glen.
The Luas Red Line is operating from Red Cow to The Point, but there is no service from Red Cow to Tallaght, nor from Red Cow to Saggart.
They say the frequency of their trams is between 20 and 30 minutes.
Meanwhile, homeless shelters have been inundated with people seeking accommodation during the cold snap.
On Saturday night the Peter McVerry Trust had 121 beds allocated in their extreme cold weather facility.
The Housing First Street Intake team observed 14 people sleeping rough in Dublin City Centre last night, three of whom took up the offer of emergency accommodation.
Council crews are out this morning clearing road gullies to prepare for snow melt & mitigate against pooling water. Our gritting crews have been out on the road since 0800 and will be all day. #StormEmma #CleanUp #backinbusiness pic.twitter.com/9uZ0NTnKqV— dlrcc (@dlrcc) March 4, 2018
In Kildare, four people sleeping rough in Newbridge accepted an offer of emergency accommodation.
Update - 12.03pm: The Status Orange Snow-ice warning has been extended for Leinster, Cavan, Monaghan, Cork, Tipperary and Waterford.
Forecasters predict widespread lying snow and ice will continue to lead to hazardous conditions.
Also, a Status Yellow Snow-ice Warning has been extended for Connacht, Donegal, Clare, Kerry and Limerick.
Both warnings are in operation until midday tomorrow.
National Weather Warnings updated by Met Eireann.
Yellow and Orange warnings extended until Monday 12pm.March 4, 2018
Most public transport services are returning to a normal schedule today.
Anyone travelling is advised to check with their service provider for the latest updates.
Bus Eireann says the majority of their services have resumed but some delays are expected on certain routes.
Irish Rail is operating most routes with the exception of a small number which are expected to return tomorrow.
The Luas Green Line will operate a limited service while the Red Line is operating from the Red Cow to The Point.
Dublin Bus services have resumed with some minor disruptions to schedules.
Essential works are being carried out by Irish Water across the country this morning.
.@IrishWater is reporting about 18,000 people are without water, of which over 11,000 are in Wexford. Currently 66,000 people have restricted supply. Our main concern today is the increase in demand across the country which is putting severe pressure on our water treatment plants https://t.co/ATH3OhzYb0— MerrionStreet.ie (@merrionstreet) March 4, 2018
They are urging people to conserve supplies where possible, with Waterford and Cork worst affected.
9.53am: Storm Emma: Big thaw leads to risk of flooding in some areas, Most Bus Eireann and Luas services resume
The Government is hopeful the country will be back to normal by tomorrow, following days of disruption due to heavy snow and ice.
There is still a Status Orange Snow-ice warning for Munster, Leinster, Cavan and Monaghan until midday, and a Status Yellow Snow-ice warning remains in place for Connacht and Donegal also.
Met Éireann has warned that widespread lying snow and ice continuing to lead to hazardous conditions.
Good morning from Met Eireann ☀️ pic.twitter.com/ayI5jaxtgY— Met Éireann (@MetEireann) March 4, 2018
The forecaster has warned that the melting snow could lead to some to localized water flooding –“especially in the smaller mountainous catchments and in urban areas.”
The National Emergency Coordination Group has warned that the thaw could lead to localized surface water ponding where drains and gulleys are blocked.
Members of the public are asked to be on the lookout for accumulations of meltwater which could lead to flooding.
The main road network has reopened, but drivers have been warned to exercise caution and “drive at speeds appropriate to the conditions”.
Urban drivers are particularly are asked to travel at low speeds and watch for cyclists and pedestrians who may be on the road due to obstruction of footpaths.
The group said that Principal Response Agencies are still in full crisis management mode in some of the worst affected areas, adding that “it is still going to take some days for conditions to improve.”
Bus Éireann have said the majority of their services are returning to normal this morning, albeit some with delays and curtailments.
Dublin Bus say that the vast majority of routes are operating across their network.
This includes their DoDublin Sightseeing Tours.
7.09am: Storm Emma: ESB crews working to restore power, Luas Green Line out of action
Repair works are underway to return power to thousands of customers.
Apologies to our customers without power. Our crews are continuing to work this morning to repair damage from #stormemma and restore power to the remaining homes, farms and businesses. Estimated restoration times are on https://t.co/cwxXH3X4kM. #staysafe pic.twitter.com/FipNfUPrPC— ESB Networks (@ESBNetworks) March 4, 2018
Wexford remains the worst affected, accounting for up to 90% of the homes, farms and businesses still waiting for service to be restored. There are around 6,000 premises waiting for their power to come back there.
The ESB's Conor Healy says they are making progress and they also have a safety message as the thaw continues.
He said: "The improving weather conditions will mean people start to go out and some of those people may come across either fallen or low-hanging electricity wires.
"We would appeal to people not to approach those wires and to report them to ESB Networks at our emergency number 1850-372-999."
Water supply is under pressure in some areas because of increased demand, with Irish Water urging people to turn off their taps to conserve it.
Teams will be working to restore the supply today.
Some of the country's roads remain impassable but routes should improve as the snow thaws.
Met Eireann forecaster Vincent O'Shea said: "The good news, if you don't like snow, is that the snow is going to melt today, there is already a thaw underway.
"Now it will take some time before all the snow is cleared from all places, but the main thoroughfares and roads should improve dramatically today and they should be cleared of ice and lying snow."
Mostly cloudy today with scattered outbreaks of rain. The rain will be persistent at times - esp near E & S coasts, & may be of sleet over high ground. Highs of 3 to 6 degrees. Lying snow & ice will continue to melt resulting in localised surface water flooding. Moderate NE winds— Met Éireann (@MetEireann) March 4, 2018
Meanwhile, Irish Rail hopes to resume a full service on a vast majority of routes today.
The company says staff have worked flat out in extremely difficult conditions to clear lines and points from snow.
Spokesperson Barry Kenny says they are also grateful to customers for their patience while services were delayed.
Mr Kenny said: "We think that apart from Connolly to Rosslare which we hope to open in the afternoon and some regional branch lines, that we will have trains on all our routes.
"We would urge our customers to check our twitter @IrishRail or our website www.irishrail.ie for the latest information before travelling."
The majority of Bus Éireann services are operating with some cancellations in the east.
Dublin Bus services are operating today, but there is still disruption to a number of services while the Luas is operating on the Red Line from the Point to Red Cow.
Maintenance teams are working flat out to clear snow from Luas tracks and platforms across Dublin.
Operators, Transdev, say there is still up to 5ft of snow on the Green Line at stops south of St Stephens Green and it will be mid-morning before service resumes.
A precise time will be announced following an early-morning inspection.