Clonshaugh named as location for north county Dublin sewage plant

The new €500 million regional sewage treatment plant to serve up to 700,000 in north county Dublin and surrounding areas is to be built at Clonshaugh near Dublin airport.

Three locations had been shortlisted for the 20-hectare facility: Annsbrook and Newtowncorduff near Lusk, both with an outfall near Loughshinny, north of Rush, and Clonshaugh with an outfall near Ireland’s Eye south of Portmarnock.

The preferred site for the plant, which is named as Clonshagh on Ordnance Survey maps, was announced at a Fingal County Council meeting this afternoon. Project managers with Dublin Greater Drainage said the site, which is 2.2km east of Dublin airport and between the Malahide Road and the M1, is ecologically and environmentally better.

Plans also include a 26km orbital sewer to pump sewage from across Dublin and parts of Kildare and Meath.

The plant will be second in size only to Ringsend and has been a cause of controversy for the past seven years. Over 10,000 residents lodged objections against the facility, fearing it will have a detrimental effect on farming and horticulture and destroy the local fishing industry and coastline.

A statement on the Greater Dublin Drainage website said the preferred site was the best solution for the future development of waste water treatment capacity in the wider Dublin region.

It said tunnelling of the preferred outfall is technically easier and the outfall location has a greater depth of water for treated water discharged into the sea. It would also have the shortest pipeline and therefore a shorter construction time and it is closest to the existing areas where waste water is drawn from and so will be more flexible in serving schools, hospitals, houses and industry immediately as well as enabling additional capacity.

It said the estimated overall cost of half a billion euro would be more than €80 million less than other options studied.

The need for a second regional plant for Dublin and its surrounding counties was identified in the Greater Dublin Drainage Study, which was commissioned by Fingal County Council on behalf of the four Dublin local authorities and published in 2005.

Initially, Portrane was earmarked as the location of the site but after vocal opposition, Fingal councillors ordered a review of the study.

The review still recommended the construction of a single treatment plant in north county Dublin and recommended nine potential locations, although it ruled out Portrane on the basis of suitability.

Opposition groups had warned that a single, large plant could pose a major threat to the environment and called for the construction of a number of smaller plants. "This is not the correct solution," Reclaim Fingal chairman Brian Hosford said in December 2011. "The potential for environmental disaster with a plant this size is enormous. There should be a series of local plants instead of pumping sewage from everywhere around the M50 into Fingal."

The plans also drew opposition from a number of sports organisations including fishing and gun clubs, as well as the Irish Farmers Association.

Fingal County Council published the shortlist of three sites last year.

Project engineers will carry out further technical investigations following the announcement of the chosen site and a planning application is expected to be submitted to An Bord Pleanála next year.