Irish Water confirms that due to a sudden increase in ammonia levels over the weekend in the River Liffey, which supplies the raw water to the Leixlip Water Treatment Plant, chlorine levels in the water supply were increased to ensure the safety of the drinking water. Customers in Leixlip and in parts of Fingal would have experienced a change in taste to the water supply over the weekend.
As ammonia interferes with the chlorination process, it was necessary that chlorine levels at the plant were increased to ensure disinfection efficiencies were maintained.
Water quality monitoring is carried out on a daily basis at Leixlip Water Treatment Plant, this includes testing of the raw water entering the plant, the effectiveness of the various treatments and the treated drinking water from the treatment plant.
While residents would have experienced a change in taste over the weekend, Irish Water wish to reassure that all tests performed on the treated water fully complied with the drinking water quality standards. Providing safe clean drinking water is a priority for Irish Water.
The ammonia levels in the raw water supplying the Leixlip Water Treatment Plant have now returned to normal and the chlorine levels have also been reduced.
Investigations are being carried out to established the cause for the sudden and temporary elevation in ammonia levels in the River Liffey which could come from many sources due to the large catchment area. Irish Water is liaising with all Local Authorities in the catchment area on the matter.