The £353 million (€448 million) contract for the design and construction of the Dublin Port Tunnel has been awarded to a consortium which includes firms from the Republic, Japan and the UK.
Construction of the Port Tunnel by Nishimatsu Mowlem Irishenco (NMI) is to begin early next year and will take more than three-and-a-half years to build, according to Dublin Corporation. It will run from the M1 at Santry to link with Dublin Port. The 5.6 km project will be constructed as a dual carriageway motorway with 4.5 km in tunnel.
It was estimated last year that the project would cost £175 million. Dublin Corporation said the increase in costs this year reflected a higher than anticipated construction-cost inflation, measures to meet concerns of residents expressed at the public inquiry and work which had not been catered for in the earlier estimate.
Mr Hugh Creegan, deputy project engineer at Dublin Port Tunnel, confirmed that an Austrian company, Geoconsult, would not be involved in the contract to design or build the tunnel. Geoconsult was the consultant to Dublin Corporation on the project and was opposed by local residents because a tunnel it constructed at Heathrow Airport collapsed in 1994.
Dublin Corporation said it would shortly be putting out a tender for a firm to supervise and monitor the design and construction of the project.
The Port Tunnel will comprise two tunnels for two traffic flows. Mr Creegan said a spray-on concrete system - whereby concrete would be sprayed on to the inside of the tunnel rather than erecting pre-cast concrete - would only be used for passageways linking the tunnels. This type of support was used by Geoconsult in the Heathrow tunnel which collapsed in 1994. Residents have also expressed concern about the use of this method for the Port Tunnel.
The tunnel will be constructed using two tunnel-boring machines, which can be up to 200 metres in length and cost between £10 million and £20 million. The machines bore the tunnels, remove excavated material and then erect pre-cast concrete to support the tunnel.
"This significantly reduces the construction impacts at all the properties above the tunnel and the use of two machines rather than one accelerates the overall construction process," Dublin Corporation said.
Mr Creegan said he expected several hundred people to be employed during the project.
The three firms involved in the consortium to design and build the project include Nishimatsu Construction Company, a Japanese firm with tunnelling experience in other countries, Irishenco Construction Company, an Irish civil engineering contractor and Mowlem & Company, also a civil engineering contractor.
The Taoiseach, Mr Ahern, said he welcomed the awarding of the contract for the construction of the Port Tunnel. "This is a major milestone in improving Dublin's transport. The Dublin Port Tunnel is a crucial element of the Dublin Transport Initiative and is designed to rid the city centre of an inappropriate burden of heavy goods traffic travelling to and from Dublin Port. It will bring particular benefit also to residential areas in and close to the north inner-city," he said.
He added it would be constructed to high safety and environmental standards.
However, Mr Finian McGrath, an independent councillor for north central Dublin, said he was concerned that the project was going to go ahead without a full process of investigation into the effects. "It's a PR and con trick to try to create an image that they're going to deal with traffic on the northside," he said.
Mr McGrath said the effect of the project would be to reduce incoming traffic into Dublin to one lane and so would disrupt traffic during construction. "The people of Marino and Santry are not going to be happy about this. It's a public safety and an environmental issue," he added.
