THE STATE is to spend €220 million to upgrade Dublin’s municipal sewage plant at Ringsend, which has been working at overcapacity since it opened eight years ago.
The plant, which cost €300 million, brought to an end the dumping of more than 40 million gallons of raw sewage into Dublin Bay each day when it opened in June 2003.
However, while the plant substantially improved water quality, a noxious smell persistently affected the surrounding communities of Ringsend, Irishtown and Sandymount for years after its opening, largely due to the plant’s inability to cope with the volume of waste pumped in from the city’s sewerage system.
In November 2003 the city council reached agreement with the government to extend the plant, which had the capacity to deal with the sewage of approximately 1.7 million people but was receiving sewage equivalent to a population of 1.9 million.
Work on the extension could not go ahead until the odour problem had been resolved. Almost €40 million was spent on odour alleviation measures and by the end of 2008, the problem was substantially addressed.
In July 2010 the Environmental Protection Agency issued a waste water discharge licence to allow for the extension and upgrade of the licence. To comply with the terms of the licence, work must by completed by 2015. The council will next month begin public consultation on the upgrade which will take three years to complete.
The work will involve extending 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.
Waste water processed by the plant is discharged directly into Dublin Bay. Council executive manager Pat Cronin said the plant was “struggling” to meet discharge standards for water quality in the bay.
The “greenest and most economical” solution was to stop all discharge into the bay and instead construct a pipeline under the sea bed which would bring the treated effluent 9km out to a point approximately in line with Howth and Killiney. This would be “outside sensitive waters” Mr Cronin said, and would allow the final effluent to be diffused out to sea.
While the extension will ease the strain on the capital’s sewerage system, a new regional sewage plant is still required. Planning for the new plant, which will serve Dublin city and county as well as parts of Meath and Kildare, is under way and a shortlist of sites is expected to be published later this month.
The need for a second large-scale municipal plant was confirmed in a study published by the Dublin local authorities in 2005. The Greater Dublin Strategic Drainage Study identified Portrane as the best site but Fingal councillors rejected the plan and ordered a review of the study.
The review, completed in 2007, found existing sewerage systems were not adequate to cope with demand and that a single regional treatment plant was best. It recommended that the plant still be located in the “northern greater Dublin area”, but not necessarily Portrane. It did not rule out Portrane, which may still be one of the shortlisted locations.