DUN Laoghaire-Rathdown Co Council will shortly seek sanction from the Minister for the Environment for the proposed South Eastern Motorway, which will cut through part of Leopardstown Racecourse and the British ambassador's official residence.
The route was approved by county councillors on Wednesday, following months of debate about alternative options. However, the £91 million motorway linking the proposed Southern Cross Route with the Bray-Shankill bypass, is unlikely to be completed for at least three years.
Mr Des Taylor, deputy county manager, said it would first require the making of a Motorway Order, which would be submitted to the Minister complete with an environmental impact statement (EIS). Then, there would be a public inquiry, "possibly in the autumn", he added.
Depending on the outcome of this inquiry - which would be focused essentially on the compulsory purchase orders for the acquisition of land - Mr Taylor said it would probably be next spring of before final approval is given, allowing for the construction phase to be started.
He emphasised that Leopardstown Racecourse was not threatened by the scheme. Only the existing six-furlong straight would be sacrificed, but there were plans to replace this with an alternative straight on the site. It would also only "skirt" the grounds of the British embassy residence.
The preferred route, known as option A, was adopted by Dun Laoghaire-Rathdown councillors on foot of the findings of a quite technical draft EIS presented to them by the chief planning officer, Mr William Murray. The full EIS is still being completed for submission to the Minister in July.
According to Mr Murray, the "A" route would be less environmentally damaging than the alternatives which were examined by the design team; it is also significantly cheaper, by some £20 million because it runs through open land in the midst of an otherwise built-up area.
It would necessitate the demolition of IS houses, compared to 35 for the "B" option. Many fewer houses - 169 as opposed to 858 - would be located within 300 metres of the route, and the impact on archaeological sites would also be less significant, according to the draft EIS.
The aim of the South Eastern Motorway is to complete the M50, or "C-ring" bypass around Dublin. It would link the Southern Cross Route, running between Tallaght and Sandyford, with the Shankill-Bray bypass. Work on the Southern Cross Route is scheduled to start this year.
If the South Eastern Motorway was not built, the draft EIS warns that traffic from the remainder of the C-ring would discharge onto Leopardstown Road, leading to "rat-running" through residential areas. There would also be "intolerable congestion" over long periods of the day.
Last month, The Irish Times revealed that Dun Laoghaire-Rathdown County Council had commissioned a consultancy study to identify a link between the South Eastern Motorway and the Stillorgan Road at St Helen's, near Booterstown. This would open the way for a full Eastern Bypass.
