Dublin's proposed metro line linking Swords with St Stephen's Green is set to cost more than €5 billion, The Irish Timeshas established from documents released by the Department of Transport under the Freedom of Information Act.
Although all monetary figures in the documents are blacked out, it is possible to discern that the estimated cost of the 17km metro north line was put at €4.58 billion in 2004 prices. With construction inflation and additional expenditure, it would now be well over €5 billion.
The extra spending arises from the provision of an additional underground station at Parnell Square as well as a promise that the section of the route running through Ballymun would be underground, rather than on the surface as originally proposed.
The price tag for the city's first metro line makes it by far the most expensive infrastructure project in the history of the State - at least three times more costly than the M50 (€1.6 billion) and six times more than either the two Luas lines or the Dublin Port Tunnel.
As well as metro north, the Railway Procurement Agency (RPA) is pursuing plans for metro west, a 25km line linking Tallaght with Ballymun, via Clondalkin, Blanchardstown and a number of Luas lines, serving Citywest, Docklands and Cherrywood/Shanganagh.
No estimates of the likely cost of these projects have been revealed by the Department of Transport or the RPA, ostensibly on the basis that the figures are commercially confidential.
However, it is more likely that they are being suppressed for political reasons.
The documents were released after an appeal to the Information Commissioner, following a Freedom of Information Act request in November 2005 seeking details on the Government's €34.4 billion Transport 21 investment programme.
They show that Iarnród Éireann submitted a 10-year capital programme, with an overall price-tag of €3.4 billion, to electrify much of Dublin's suburban rail network and build an underground rail interconnector between Heuston Station and Spencer Dock.
Iarnród Éireann has conceded that the original estimate for the interconnector, which would have intermediate stations at Thomas Street, St Stephen's Green and Pearse Station, would now be substantially dearer than the original €1.3 billion estimate in 2002.
The Cabinet subcommittee on infrastructure gave priority to the metro north project, however, and the RPA recently submitted it to An Bord Pleanála for fast-track planning approval.
