Boil water notice set to end today once final test results return clear
Irish Water's crisis management team meets again today as it awaits the outcome of test results it hopes will allow the go-ahead to lift the boil water notice affecting 600,000 people.
Samples of water taken at the Leixlip Water Treatment Plant which serves large parts of Dublin, Kildare and Wicklow came up clear of contamination late last week.
But the HSE insisted on having three more days of tests to be certain there was no risk to householders' health from drinking directly from their taps.
Final results of those tests are due back from Dublin City Council's lab today and, if they are also clear, the plan is to declare the country's biggest ever boil water alert over.
Doubts remain, however, over the Leixlip plant's ability to get through the winter ahead without running into further difficulties.
Irish Water management has warned that there could be more boil water notices affecting the same group of people.
The company is currently replacing filters in the old part of the plant, which treats most of the water required by the region's homes and businesses.
That work began last year but it has to be carried out gradually so may take until the middle of next year to complete.
"It's like changing a tyre on a moving car," an Irish Water spokeswoman explained. "We can't stop production of water to let us carry out the work more quickly. If we did, there would be water shortages."
However, the company is trying to speed up the replacement work and is drawing on other treatment plants at Vartry and Ballymore Eustace to ease the pressure on Leixlip so that workers can make faster progress.
The work is only part of the overhaul of the treatment plant that will be necessary to ensure clean water into the future.
The Environmental Protection Agency (EPA) has visited the plant twice in recent weeks and said that even after the boil water notice is lifted and the filters replaced, it still believes an additional layer of treatment will be needed to ensure the safety of the water in the longer term.
The EPA wants disinfection by ultraviolet light to be added to the treatment process. Irish Water says it is assessing how much that would cost and how long it would take.
A boil water notice was issued eight days ago after heavy rain caused cloudier than usual water to enter the plant.
The older filters were unable to clean it enough to be certain that disease-carrying parasites didn't slip through to the drinking supply.
The same customers were also under a boil water notice for three days last month.