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DART Underground

General DART Underground Information

Iarnród Éireann has developed plans for a new underground second DART line through the heart of Dublin city centre.

The DART Underground rail line, which would run from Docklands to Inchicore, would complete the trebling of the Greater Dublin area's rail service capacity from 33 million passenger journeys annually now to 100 million passenger journeys upon completion.

The DART Underground tunnels will be approximately 7.6 Km in length and will connect the Northern and Kildare rail lines, with underground stations strategically located at Spencer Dock, Pearse, St. Stephen’s Green, Christchurch and Heuston Station, as well as a new surface DART station at Inchicore.

A Railway Order for the DART Underground was granted by An Bord Pleanála on 15th December 2011.   The full decision is available from An Bord Pleanála's website.

Subject to the granting of the Railway Order and the availability of funding, the construction of DART Underground will take approximately six years.  However, the project has been deferred due to the reduction in the capital investment programme.

DART Underground is not a stand-alone project but is the vital link in a wider package of measures, including:

  • electrification of the lines to extend the DART to Balbriggan, Maynooth and Hazelhatch
  • signalling and track capacity enhancements to allow more trains to run more frequently
  • significant expansion of the fleet and train depot facilities.

All of these works will pave the way for the completed DART Underground to fill in the crucial final link that will release the full potential of this expanded and improved rail network into and out of Dublin.

DART Underground will be the single most important piece of infrastructure in the state to ensure a modal shift from private to public transport, and free future generations from the gridlock which cripples the Greater Dublin area today. It also links all rail modes - DART, Commuter, Intercity, Luas and proposed Metro - to form an integrated cohesive transport network.

The design and planning of the project is funded by the Irish Government and is also being part-funded by the Ten-T Executive Agency of the European Commission.

The new line will dramatically increase frequency and capacity for commuters on DART Northern, Maynooth and Kildare lines - the three fastest growing population corridors in the country - and relieve the current congestion at Connolly Station. Development plans also include the extension of the DART network to Maynooth, Hazelhatch/Celbridge and the Northern line.

DART Underground provides the missing link that that will deliver a fully integrated rail network for the Greater Dublin Area, linking all modes and ensuring that suburb to suburb, as well as suburb to city centre, journey's can be made by a frequent, high capacity public transport network.

The new line will dramatically change Iarnród Éireann's DART and Commuter network. Northern line DART services from Balbriggan and Howth will branch off the existing DART line after Clontarf Road, going underground to new stations and opening up a web of new rail connections:

  • Spencer Dock Station connects with the expanded Luas Red Line
  • Pearse Station will become a central transport hub as both DART lines interchange there, opening up a variety of new rail connections and options. Pearse will also link with outer Commuter services.
  • St. Stephen’s Green will have convenient access to the Luas Green Line and the proposed Metro North to the Airport and Swords.
  • Christchurch with future Luas City Centre-Lucan line.
  • Heuston Station links to Intercity services from the South and the West, outer Commuter trains and the Luas Red Line.
  • Inchicore with the Kildare DART line and the planned Luas City Centre-Lucan line.

The Docklands to Inchicore Interconnector will deliver:

  • A second high capacity DART line through the heart of the city centre, a 7.6 kilometre underground line
  • Dramatically increased frequency and capacity for services on the Northern, Maynooth and Kildare lines - the three fastest growing population corridors in the country – and relieving the current congestion at Connolly Station
  • A fully integrated rail network for the Greater Dublin area, linking all modes - DART, Commuter, Intercity, LUAS and Metro - and ensuring that suburb to suburb as well as suburb to city centre journeys can be made by a frequent, high capacity public transport network
  • Two high capacity DART lines proposed as Balbriggan/Howth to Hazelhatch; and Maynooth/Dunboyne(M3) to Bray/Greystones, with DART extensions to some routes likely to be delivered in advance of the DART Underground
  • A trebling of the capacity for passenger journeys by DART and Commuter rail annually - up from 33 million today to 100 million
  • A critical piece of urban, regional and national infrastructure
  • Up to 7,000 jobs during each year of the construction phase, with many thousands more jobs indirectly as a result of the significantly improved access that the project will deliver to retail, commercial, leisure and tourist destinations in Dublin.

Project Progress

Railway Order Application

The DART Underground rail project took another significant step forward on Wednesday, 30th June, 2010 when the formal application was lodged with An Bord Pleanála for the Railway Order granting planning approval for the construction of this key public transport infrastructure scheme.

The An Bord Pleanála public Oral Hearing for the DART Underground Railway Order application commenced on 22nd November 2010 and concluded on 8th April 2011. A Railway Order for the DART Underground was granted by An Bord Pleanála on 15th December 2011.  

The Railway Order is the equivalent of a planning permission for new rail schemes and, if granted, will authorise CIÉ to construct, maintain and operate the DART Underground, subject to funding availability. The project will involve the construction and operation of approximately 8.6 Km of new rail (7.6 Km of which will be in tunnels) from the CIÉ Inchicore Works to tie into the Northern mainline south of East Wall Road and north of the Docklands area. The project will be managed on behalf of CIÉ by Iarnród Éireann, supported by expert advisers with international experience of similar major infrastructure projects.

The twin tunnels will be constructed using two Tunnel Boring Machines, launching from the Docklands, at an average depth of 24 metres, or some 80 feet, below ground level. The underground stations will be constructed using techniques that will minimize the effect for the local residents, communities and environment.

Business case

The business case for the project was undertaken by Colin Buchanan & Partners Ltd, a leading international transport planning and economics consultancy, and it concluded that the economic case for DART Underground is very strong and that overall the completion of the system is crucial to the future economic development of Dublin. It forecasts that the DART Underground programme will generate 2.4 times more benefit than it will cost to build and will deliver significant wider economic benefits. This statistic demonstrates that DART Underground will be a major factor in the future economic development of the country.

DART Underground Business Case (17Mb)