The foul odour which has emanated from Dublin's main sewage plant on the Poolbeg peninsula in Ringsend since the facility was built in 2003 will be eliminated by next July, Dublin city manager John Tierney has pledged.
Although work is already taking place to address the problem, complaints in relation to the smell increased last year by almost 500 per cent, compared with 2006. The €300 million plant, which opened in June 2003, brought to an end the dumping of more than 40 million gallons of raw sewage into Dublin Bay each day. However, while the plant substantially improved water quality, a putrid smell has regularly affected the surrounding communities of Ringsend, Irishtown and Sandymount.
The plant was built under a public private partnership with the ABA consortium, involving Ascon, sewage specialists Black & Veatch and Anglia Water. The council has refused to sign over full control of the operation of the plant to the consortium until the odours are eliminated.
A number of attempts to control the odours were made in the first two years of operation of the plant but these were largely unsuccessful. Following an independent review of the operation of the plant by a US engineering firm in 2004, the consortium agreed to a programme of engineering works to eliminate the smell.
Short-term works began in 2006 involving the installation of "odour friendly" sludge processing equipment, new odour control units and upgrading of settlement tanks. This was followed by a more comprehensive programme of engineering works which began last year which, it is intended, will eliminate the smell permanently.
Odour complaints made to the council in 2007 far exceed those of 2006. Some 60 complaints were made in 2006 compared with 286 in 2007, with complaints peaking in June last year at 105.
The high level of complaints in the summer were due to the sludge drying process, the council said. Relatively high numbers of complaints in April (62), September (27) and March (24), were also due to the drying process, the council said.
The driers are expected to be upgraded by the end of spring 2008. The programme of works will not be finished until November, but Mr Tierney said the smell should be gone by July.
He said the council was now planning to expand the capacity of the plant. A design brief was issued in recent weeks to a number of shortlisted consultants and bids for the extension, which it is estimated will cost over €50 million, are expected shortly.
A new plant, to be built somewhere on the north Dublin coastline, will allow for the development of the greater Dublin region up to 2030.