More than 600,000 homes and businesses in greater Dublin, forced to boil water because it may be unsafe, face further disruption in the months ahead even if supplies are cleared for consumption on Tuesday, Irish Water has admitted.
Niall Gleeson, managing director of the utility, said he would like to shut down the Leixlip Water Treatment Plant – which is at the centre of the pollution concerns – and "blitz the whole thing" but he can't because it feeds a fifth of the capital's taps.
Instead, Irish Water is carrying out necessary upgrades on filters at the plant bit by bit to keep it in operation.
Mr Gleeson accepted this meant more boil water notices could be issued again until the upgrade works are expected to be completed sometime next spring. Measures were also being put in place to help the plant cope with weather events expected over the winter.
“We are hoping it will be more resilient but there is the possibility we will have to restrict that plant (again),” he said.
The latest boil water notice – the second in as many weeks, affecting much of north Co Dublin, as well as parts of Kildare and Meath – will not be lifted before Tuesday. It came into force last Monday.
‘High turbidity’
Heavy rainfall and conditions in the Liffey were blamed for “high turbidity levels” – water cloudy with matter or sediment – which led to the risk of microscopic parasites, Cryptosporidium and Giardia, in the water supply.
The Environmental Protection Agency (EPA) described the turbidity levels as “unacceptably high”.
Officials from the EPA, Irish Water and the Health Service Exectuive (HSE) carried out an “audit” at the Leixlip plant on Friday.
Mr Gleeson said all agreed that it was working satisfactorily again since around 5pm on Wednesday, but in order to give the HSE “more confidence in the plant” they wanted to continue testing until Sunday.
The results won’t be available until Tuesday.
“At that stage, assuming all the samples have passed or are satisfactory, we will be able to lift the boil water notice at some stage on Tuesday,” he told RTÉ.
“Ideally, if we had more head room in Dublin I would shut down that plant and we would have done the works in a six to 12-month period - just blitz the whole thing.
“But because we have to keep production going and because it is 20 per cent of the supply (for Dublin) we’ve got to carefully do those works while the plant is running.”
Mr Gleeson added that the country’s water infrastructure generally was “not in a good place” and he appealed for patience from the public as boil notices may be issued elsewhere.
‘Ultraviolet disinfection’
The EPA has warned the “the ability of the Leixlip plant to maintain an appropriate level of performance remains a concern”.
“Irish Water are undertaking filter upgrade works to address the immediate treatment deficit at the plant,” it said in a statement.
“However, an additional treatment barrier may be required, such as ultraviolet disinfection as recommended in the EPA’s previous audit.
“The EPA awaits Irish Water’s report on this matter which is due by 30th November.”
Minister for Housing, Planning and Local Government Eoghan Murphy voiced his “extreme disappointment” that the boil water notice will continues for at least several more days.
“People in the affected areas have shown incredible patience and fortitude in the face of this ongoing major disruption to daily life and business, and I thank everyone for that,” he said.
“Regretfully, the audit today has found that more work is needed to make the Leixlip plant operate safely again.
“Irish Water must now progress these works without any delay.”