A new orbital motorway outside the M50, linking the M1 at Drogheda with the M9 at Kilcullen is "economically viable", according to an evaluation submitted to the Minister for Transport by the National Roads Authority.
In documentation released to The Irish Times under the Freedom of Information Act, the Department of Transport also says a corridor linking Drogheda to Navan and to Naas has been "identified as the optimum route" and would be "strategically beneficial" to the region.
The new road of approximately 80km would link the M1, M3, M4, M7 and M9 and connect a necklace of towns including Drogheda, Slane, Navan, Trim, Kilcock and Kilcullen.
The NRA contracted Goodbody Economic Consultants to carry out feasibility work on the route and it is understood that a two- to three-lane road of motorway standard carrying between 35,000 and 55,000 vehicles per day was seen as likely to bring significant economic and lifestyle improvements to the region. Based on 2007 costings and looking at road projects of a similar magnitude, the cost of the project is projected at approximately €1 billion.
To put this in context, the upgrade of the M50 is costing a similar sum. A spokeswoman for the Minister for Transport, Noel Dempsey, confirmed he was examining the NRA report in detail.
"It is fair to say that the Minister is, in principle, positively disposed to the construction of the outer orbital route," she said, saying that the Minister would make a decision in September. She added that the report would be published along with the Minister's decision.
However, even if the Minister were to give the project the go-ahead next month, it could take up to 10 years to complete, with construction requiring approximately four years.
In an interview with The Irish Times this week, Fred Barry, chief executive of the NRA, said its recommendation was that the project should proceed to the next stage - which involves further engineering and environmental work - before making an application to An Bord Pleanála for statutory approval.
"Strategically, we have no concerns about this project being a very positive thing. During the engineering and financial analysis, it became quite clear that the right thing to do was to connect the main towns outside of Dublin and to give strategic connection to Drogheda, Navan, Trim and Naas."
The route would provide an alternative to drawing all non-Dublin traffic towards the capital and would also act as an alternative to the congested M50.
Mr Barry added that there appeared to be support within Government for the project. "During the election a number of Ministers spoke positively about it and I would say informal indications are that it has at least a degree of support within the Government."
He said that apart from the economic benefits, such a route would significantly improve the quality of life for residents in this region.
"There is already quite a bit of traffic looking to use the local and regional roads out in those areas. There are quite a few areas that a couple of years ago would have been quiet country roads and are now commuter runs."
Such a motorway would also provide a natural link to the proposed site of the new port at Breamore, near Drogheda, were it to move from Dublin. How the project would be funded is not yet clear, as it is outside Transport 21.
Since Mr Barry also said he does not see significant increases in tolling on the motorway network, this suggests that either the Exchequer footing the bill or a public-private partnership based on phased payments, are the most likely options. Mr Barry said the NRA has almost completed a feasibility study on an eastern bypass, linking the Dublin Port Tunnel with the M50 close to Sandyford. He said two options were examined - one involving tunnelling and the other a viaduct over Dublin Bay. "We will submit a report based on a detailed examination of the costs and engineering implications to the Minister by late September."