In June 2003 the Ringsend waste water treatment works began operating, bringing an end to the dumping of more than 40 million gallons of raw sewage into Dublin Bay each day. The following November Dublin City Council reached agreement with the then government to extend the plant, which had cost €300 million, because the plant could not cope with the loads of sewage it was receiving.
The plant substantially improved water quality in Dublin bay and resulted in beaches with previously severely polluted bathing waters, such as Dollymount, meeting blue-flag standards. However, even on its first day of operation the plant did not meet the EU waste water treatment directive standard and a noxious smell persistently affected the surrounding communities for years.
Waste volume
The smell was largely due to the plant's inability to cope with the volume of waste pumped in from the city's sewerage system. It had the capacity to deal with the sewage of about 1.7 million people but was receiving sewage equivalent to a population of 1.9 million when the loads from industry were taken into account.
Some €40 million was spent on odour alleviation measures and by the end of 2008 the problem was substantially fixed. However, the capacity problem and the failure to comply with EU standards still needed to be addressed.
In 2011 the council announced its intention to extend the capacity of the plant to a 2.1 million population equivalent on a seven- acre site within the curtilage of the current facility and the construction of a 9km pipeline to bring the treated waste water outside Dublin Bay for disposal.
The council secured permission for the scheme from An Bord Pleanála in November 2012 but last year the project hit a stumbling block when the Sandymount and Merrion Residents' Association took a High Court action against the construction of the pipe. The association lost the case but as a result of the delay no contracts had been signed for the scheme before the handover to Irish Water last January.
New technologies
Irish Water's engineers said new technologies have emerged in recent years that are suitable for upgrading the plant and would cost far less than the pipeline option. A system in operation in the Netherlands for about five years will be used to retrofit the tanks in Ringsend, solving the water standards problem. The expansion, the less costly element of the council's scheme, will go ahead.
The council’s plan was not foolhardy, Irish Water said. It would have provided the service required for the next 50 years, whereas the new solution probably has a lifespan of 20 years. However, unlike the council, Irish Water has to look at how it spends money nationally, not just locally, a spokesman said.If Dublin had got its pipe, somewhere else would have lost out.
“We are about reducing risks across existing assets rather than solving everything forever and a day. If we did that we would end up with some super plants and some other very bad plants,” the spokesman said.