The Government has approved the development of a £4.3 billion metro system for Dublin, one-fifth of which will be underground. The 70km metro is being planned in addition to the proposed Luas light-rail system, which is on schedule for completion by the summer of 2003.
The aggregate cost of both projects is estimated at close to £5 billion.
The Government has decided to opt for a metro system because it now accepts that Luas alone would not have the capacity to cope with the growth of the city.
The Minister for Public Enterprise, Ms O'Rourke, said the metro would differ from Luas in that it would comprise a permanent segregated route which did not include junctions with any other traffic. As such, it would not be subject to traffic lights and would not have to yield right of way at any stage of its route.
On-street light rail, as proposed in the Luas system, can cope with just 6,500 passengers per hour. Buses and Quality Bus Corridors can take another 5,000 passengers per hour.
By contrast, the capacity of a system separated from other traffic, such as the proposed metro, is 56,000 passengers per hour, according to the Department of Public Enterprise.
Ms O'Rourke said yesterday that she expects the metro system to take between seven and 15 years to plan and build.
The first Luas line, Line A from Tallaght to Abbey Street, is on schedule to be operational in the winter of 2002. Public private partnership (PPP) operators are to be chosen to operate both the Luas and metro systems.
The circular metro route will take in Kimmage, Tallaght, Quarryvale, Blanchardstown and Connolly and Tara Street stations in the city centre, integrating with the DART, Arrow, mainline rail and Luas services as well as with Dublin Bus and Bus Eireann services.
It includes spurs to Swords via the airport, and to the DART line at Shanganagh, near Bray, via the former Harcourt Street line. A smaller spur will serve Citywest from Cookstown.
The former Harcourt Street line is to be reopened as Luas Line B between St Stephen's Green and Sandyford, as planned, but will at a later date be reclassified as metro and extended to Shanganagh. Carriages will then have the option of travelling on surface all the way into the city centre or of going underground at Ranelagh.
Initial indications are that the metro will have to go underground at Clondalkin, beneath the existing Kildare line, and in the vicinity of the airport.
The Luas Line A from Tallaght to Abbey Street is already under construction and will interchange with suburban and mainline bus and rail services at Heuston station. Luas Line C from Abbey Street to Connolly Station will provide another interchange with mainline and suburban rail.
Total peak-hour trips in Dublin city grew by 78,000, or 45 per cent, between 1991 and 1997. However, the bulk of this growth was accounted for by private car journeys, which increased by 71,100 trips during the period.
Instancing other European cities which have introduced metro systems, Ms O'Rourke said their benefit was that they were separate, dedicated systems which could operate independently of other traffic and were not slowed by junctions.
It was for this reason that the dedicated Harcourt Street line between Ranelagh and Shanganagh would be subsumed into the metro system, as it was unlike other aspects of the light rail in that it was not on-street.
Commenting on the timeframe for the plan, Ms O'Rourke said: "We are rushing to catch up."
She announced that her Department had already appointed a consortium of consultants to design and run a competition to select the Luas operator. This competition is expected to be finalised in 12 months.
Legislation to establish an independent statutory agency with responsibility for the procurement of both PPP operators is expected to be introduced to the Dail early next year.
