Dublin Area Rapid Transit

The section of trackbed between Dún Laoghaire and Dublin City was originally laid out as part of the Dublin and Kingstown Railway, Ireland's first railway. This line was later connected with the Belfast mainline to the north and Wexford mainline to the south and joined the Harcourt Street line at Shanganagh Junction. The scenic views from the railway over Dublin Bay at this point have been favourably compared to those on the Gulf of Naples[3] and have resulted in trips to Killiney Hill and Greystones along the line becoming popular tourist attractions.

Prior to electrification in 1984, the line was operated using 1950s era CIÉ 2600 Class rail cars which had been converted in the early 1970s to push-pull operation. These diesel-powered trains were powered by a CIE 201 Class locomotive with a driving trailer carriage on the other. This service was notoriously uncomfortable, unreliable and overcrowded. By the late 1970s, the need for an urgent upgrade to the system had become apparent as the 2600 Class railcars were in poor condition. Replacement parts had become increasingly difficult to obtain due to the age of the rolling stock and its conversion to push-pull operation, which had been intended as a temporary measure until a more permanent solution could be established, had come to the end of its serviceable life.

In advance of electrification, three new stations at Sandymount, Booterstown and Salthill and Monkstown were added to the network in 1984. Sandymount and Booterstown were each built at the sites of a previous station while Salthill and Monkstown were built near the site of the original Kingstown railway terminus, between Seapoint and Dún Laoghaire. As electrification work was undertaken from 1981–1982, a spur which had served the ferry port at Dún Laoghaire was disconnected from the mainline as the installation of overhead power lines to service the harbour would have necessitated the lowering of the track which travelled through a portal south of Dún Laoghaire station.

Early DART services ran from the north-eastern suburb of Howth, through Connolly, Tara Street, and Pearse stations in the city centre and on to Bray which lies on the border between Dublin and Wicklow. This route remained unchanged for almost sixteen years at which point the line between Bray and Greystones was electrified. Further electrification of the line took place between Howth Junction & Donaghmede and Malahide, the northernmost DART station, on the Belfast mainline.

All trains in the Dublin suburban area, including DART services, are monitored and regulated by a Central Traffic Control (CTC) facility located in Connolly Station, known as Suburban CTC. This facility has been extensively automated and requires a staff of five; two signallers, one with responsibility for level crossings, an electrical control officer, who supervises the electrical power supply equipment and an overall supervisor. The main CTC is staffed at all times however, there are also backup local control rooms which allow services to continue in the event of serious technical problems.

A single driver is responsible for the management of each train from the cab in the leading carriage. Automatic doors are controlled by the driver and are armed upon arrival at stations. Real-time passenger information displays on station platforms offer passengers updates on next train arrival times, service updates and outages. Automatic PA announcements are made in case of service disruptions and are tailored to each station.

The majority of stations on the network have been renovated to include automatic barriers which require passengers to submit their ticket for verification before they can set foot on the platform. A ticket is required in advance of boarding DART services and can be purchased at stations from manned kiosks and automated machines. Passengers can also avail of the option of using a Leap Card, Dublin's integrated ticketing scheme. Leap cards are offered as contactless cards onto which passengers can load set ticket options or a cash balance. Leap fares are typically cheaper than paying in cash for a journey. On the DART network, users tag on at their point of entry and tag off at their exit point. Irish Rail, along with Dublin's other public transport operators operated its own smart card system which was phased out to coincide with the Leap Card's introduction. Revenue protection officers check passengers tickets to ensure validity both onboard trains and on station platforms at random intervals.

In February 2018, the Irish government and National Transport Authority announced a 10-year plan to electrify the lines to Drogheda, Maynooth, Hazelhatch, M3 Parkway and Docklands.[4] Part of this plan also includes ordering 300 further EMU DART coaches and building new stations. Irish Rail is also planning on ordering 300 bi-mode units to allow longer-distance services to run electrified when under wires.

The initial phase of this is to provide 40 km of electrification to Maynooth, M3 Parkway and Docklands; with a new EMU maintenance depot at Maynooth and additional works in relation to signalling and level crossing closures. This has progressed to the design stage as of April 2019.[5]

This project, which had previously been referred to as "DART Expansion", was renamed "DART+" in 2020 when public consultation began on the design for the Maynooth upgrade.[6]

A tender for up to 600 hybrid battery/electric units was issued in May 2019, to replace the entire existing fleet and provide capacity for expansion.[7]

A tender for initial design work for electrification to Hazelhatch and of the Phoenix Park Tunnel as well as quad-tracking the remaining section of the line between Heuston and Cherry Orchard; and an additional station at the Kylemore Road was issued in June 2019.[8]

A new DART station, Woodbrook railway station, is proposed to be built between Shankill and Bray on the southern section of the dart line with an application to be submitted by the NTA in Q1 2020.[9]

Proposed DART lines
Proposed DART Line 1
Maynooth Leixlip Louisa Bridge Leixlip Confey M3 Parkway Dunboyne Hansfield Clonsilla Porterstown DM Coolmine Castleknock Navan Road Parkway Ashtown Pelletstown Broombridge Glasnevin DM Phoenix Park Tunnel to Dublin Heuston Western Commuter line Drumcondra DART Line 2/ Northern Commuter line Dublin Connolly Docklands ( Spencer Dock) Loopline Bridge Tara Street DM Dublin Pearse DART Line 2 Grand Canal Dock Lansdowne Road Sandymount Sydney Parade Booterstown Blackrock Seapoint Salthill and Monkstown Dún Laoghaire Sandycove and Glasthule Glenageary Dalkey Killiney Shankill Woodbrook Bray Greystones
Proposed DART Line 2
Drogheda Laytown Gormanston Balbriggan Skerries Rush and Lusk Donabate Malahide Portmarnock Clongriffin Howth Sutton Bayside Howth Junction and Donaghmede Kilbarrack Raheny Harmonstown Killester Clontarf Road DART Line 1/ Western Commuter line Dublin Connolly Docklands ( Spencer Dock) Loopline Bridge Tara Street DM Dublin Pearse DART Line 1/ South Eastern Commuter line St Stephen's Green DM Christchurch Phoenix Park Tunnel to Dublin Connolly Dublin Heuston Inchicore Works Inchicore Park West and Cherry Orchard Clondalkin/Fonthill DM Kishoge Adamstown Hazelhatch and Celbridge

Plans have been laid out to expand the DART network beyond the coastal mainline and provide service to the north and west of the city. These expansion plans include a purpose-built tunnel linking the Docklands Station at Spencer Dock in the city's quays and Heuston Station. This tunnel, the planned DART Underground, includes plans for services from Celbridge/Hazelhatch to the Docklands via St. Stephen's Green. To accommodate this change, the plans called for the existing line to be realigned to run from Greystones in the south to Maynooth with the electrification of the Connolly to Maynooth line. An interchange at Pearse Street was to connect the proposed lines. The DART Underground project was put on hold in September 2015,[10] however the Greater Dublin Transport Strategy 2016-2035 (published in 2016) included the DART Underground as a proposed National Transport Authority project.[11]

The southern portion of the existing DART line is to branch west after Connolly Station to run onto the Western Commuter line, which is to be electrified as far as Maynooth. The branch to Navan (currently constructed and operational to M3 Parkway with further extension also postponed) is also due to be electrified as far as Dunboyne, with the goal of increasing the frequency of services on these lines.

8329 at Howth in October 1985

The Northern portion of the DART line (North of Connolly Station) was proposed to be linked using the DART Underground to the Kildare line via Docklands station at Spencer Dock and Heuston Station. This strategic tunnel would link the DART directly with existing Luas light rail lines, hundreds of bus routes, planned Metro lines and extend the high-frequency DART service to the Kildare commuter line. A DART service originating from the Northside (i.e. Howth) would divert to the Docklands and from there through a tunnel to Heuston station to continue service on the Kildare line. In April 2009, it was announced that an electrification project would extend the DART as far as Drogheda.[12]

In October 2008, Iarnród Éireann announced plans for a significant expansion of the DART fleet, with a €900 million order for a total of 432 individual EMU cars for delivery between 2011–2012. Due to the economic downturn this delivery was put on hold.[13]

In May 2019, IÉ announced 'Invitations to Tender' for a new fleet of 300 bi-mode vehicles with the intention of extending DART services beyond the existing electrified network from 2023 onwards. A further 300 EMU vehicles are proposed to be procured to replace the 8100 Class units. The tender proposal included bi-mode trains capable of dual voltage operation, as future electrification on the Irish network is planned to be at 25 kV AC power, while the existing DART network will remain at 1.5 kV DC.[14]