A boil water notice remains in place for more than half a million people - and it won't be lifted until at least tomorrow.
Up to 615,000 people face a third day of boiling their water in Dublin , Kildare and Meath after heavy rain triggered the major notice on Monday evening.
Testing at the Leixlip treatment plant is continuing, after large amounts of organic matter was washed into reservoirs, increasing the turbidity - or 'cloudiness' - of the source water above acceptable levels.
Eamon Gallen, Irish Water’s General Manager said: "Irish Water acknowledges and apologises for the impact and inconvenience caused by this Boil Water Notice to homes and businesses.
"We are very disappointed that a Boil Water Notice has to be imposed again but as we outlined the last time, our number one priority is the public health and the safety and well-being of our customers.
“The choice we were faced with was customers having a severely restricted water supply for a long period of time or having water for sanitation purposes such as showering and flushing of toilets.
"We were left with no option but to resume production at the old plant in the knowledge that a Boil Water Notice would then be necessary.
"We will work with Fingal County Council to get the Boil Water Notice lifted as soon as possible, subject to consultation with the EPA and HSE.”
