An undetected pump problem at a treatment plant wasn’t reported for three days leading to the latest boil water notice, it has emerged.
Hundreds of households in Dublin and the surrounding areas of Co Kildare and Co Meath have affected.
An audit revealed Irish Water failed to consult the HSE about the risk to public health caused by a temporary loss of controls at their Leixlip plant in March.
The Environmental Protection Agency report said it “presented a significant risk to the safety of the water supply”.
The problem resulted from a pump failure that went undetected for almost eight hours on March 13 and 14.
This allowed particles of sludge into treated water and resulted in above-normal levels of aluminium and turbidity or cloudy water.
The EPA found Irish Water sought advice from the HSE about the high aluminium levels in drinking water but it did not refer to the HSE about “the more significant issue” relating to the temporary loss of Cryptosporidium and Giardia barriers. The audit found Irish Water also failed to take samples of treated water during the critical period following the incident. Data from the Leixlip plant also led the EPA to discover that there had been an uncontrolled release of large quantities of raw sewage into the River Liffey between Newbridge and Leixlip around the same time.
A separate investigation by the EPA found Irish Water failed to comply with the requirements of its licence over the release of sewage from its Newhall pump station on March 14, 15 and 16.
It was also in breach of its licence for taking a week to notify the relevant authorities about the discharge into the Liffey – one of the main sources of drinking water supplies in Dublin.
An EPA spokesperson said: “Irish Water should have notified the EPA, Inland Fisheries Ireland and the Leixlip water treatment plant as soon as practicable after the release of the raw sewage. Irish Water failed to do this.”
Irish Water said it had carried out a number of actions at Newhall including installing of a new alarm system.
Social Democrat and Kildare North TD, Catherine Murphy called for a “thorough investigation”.
