DART+ West Emerging Preferred Option
The preliminary options assessment studies have led to the identification of the Emerging Preferred Options for each of element of the project.
The project has been divided into sections describing the project in an east west direction, as follows:
General Linear Works
The project will require modernisation and modifications to the existing railway line/linear works in all sections of the project. Some of the key infrastructural works that will be required include:
- Overhead electrification equipment along the full extent of the railway line. This will be similar in style to that currently used on the existing DART network
- Substations will be required at intervals along the rail line to provide power to the network
- Signalling upgrades and additional signalling will be required to the upgraded infrastructure
- Interfaces with existing utilities, boundary treatments, drainage works, vegetation management and other ancillary works will be required along the length of the project
- Works required at existing rail overbridges. A number of options are being considered at existing rail overbridges that do not provide the necessary clearance/headroom for the provision of the overhead power lines, these include:
- Modification of the existing bridge structure
- Lowering the rail track under the bridge
- Provision of specialist electrical solutions with reduced clearance
- Removal of the existing structure and provision of alternative structure at the same, or alternative location
City Centre Enhancements
Connolly Station
Connolly Station is one of the main railway stations in Dublin and Ireland and a focal point for the Iarnród Éireann network. The station today consists of;
- Platforms 1, 2, 3 and 4 are used primarily for Belfast Enterprise, Sligo and commuter services to Maynooth and Drogheda
- Platforms 5, 6 and 7 are used for DART, Maynooth, Drogheda and Phoenix Park Tunnel services
- The station complex also includes a number of stabling roads (train parking) and a maintenance shed, primarily used to service the Enterprise train sets
The key issue with the current layout is that the terminal platforms are on the east side of the station, whilst the through platforms are on the west of the station. The station capacity is constrained by the number of trains and by track crossing conflicts. DART+ is seeking to modify the northern access to Connolly Station rail lines with upgrades to the existing infrastructure to facilitate the increase in capacity.
View of tracks on northern approach to Connolly Station showing multiple crossovers which restrict capacity
Spencer Dock Station
The existing Docklands Station is located southeast of Connolly Station and operates as an overflow terminus station to Connolly Station in the morning and evening peak times. DART+ works is seeking to make more beneficial use of Spencer Dock Station, so that both Connolly and Spencer Dock Stations to work in a more efficient manner together to cater for the planned increased frequency of services that will benefit all GDA routes.
Subject to further assessment, DART+ is seeking to relocate Docklands Station to Spencer Dock adjacent to the Spencer Dock Luas Stop to increase the overall rail capacity in the City Centre, to better serve the Docklands area and to maximise the interchange potential with Luas.
City Centre to Phibsborough and Glasnevin
It is proposed that both of the existing lines between Connolly and Spencer Dock to Phibsborough and Glasnevin will be electrified with the installation of overhead electrical equipment, associated upgrades, re-signalling, telecoms, electricity substations and parapet heightening as required.
The two rail lines, the Northern Maynooth and Phoenix Park Tunnel lines converge at Phibsborough/Glasnevin, to the west of Cross Guns Bridge.
At Phibsborough and Glasnevin, a new fully integrated station serving both the DART+ Maynooth Line project and the proposed MetroLink project is proposed. Iarnród Éireann and Transport Infrastructure Ireland (TII) are collaborating to provide this new station which will comprise:
- DART+ surface station. The station will have an east-west orientation on both Iarnród Éireann lines (Northern Maynooth and Phoenix Park Tunnel lines);
- MetroLink underground station will have a north-south orientation;
- A shared concourse with full passenger integration; and
- Street level access and public realm improvement
Works required at existing rail overbridges
A number of rail overbridges have been identified as having insufficient clearance to accommodate the overhead electrical equipment, for example at Newcomen Bridge on the North Strand Road. Options are currently being considered at these locations such as bridge modifications which are subject to further studies. All other bridges along this section are currently being assessed to confirm clearances and potential works required works at those locations.
Phibsborough and Glasnevin to Clonsilla Station
Between Phibsborough, Glasnevin and Clonsilla Station the Maynooth line runs alongside the Royal Canal. The line passes through Broombridge Station, where it interfaces with the Luas. Travelling in a westerly direction the line along this section includes the following stations: Ashtown Station, Navan Road Parkway Station, Castleknock Station, Coolmine Station and Clonsilla Station.
This section of the scheme extends to the west of Clonsilla Station where the line forms a spur northward along the M3 Parkway line to Dunboyne.
The level crossings along this section of the railway corridor are currently constraining train capacity on the railway corridor.
Aerial view Broombridge integrated rail and LUAS stations
In order to provide a modern transportation network and to achieve the required increase in train capacity it is proposed to permanently close the four level crossings along this section and provide new bridge crossings at appropriate locations in lieu of the level crossing closures.
Due to the proposed increased train frequency the retention of these level crossings is untenable. The closure of these level crossings will improve train efficiencies, safety and remove interfaces and associated delays with the road network.
The following sections outline the option selection process and present, the Emerging Preferred Option to address the level crossing closures with replacement accesses along this section of the Maynooth line. These are described from east to west as follows:
Ashtown Level Crossing
The Emerging Preferred Option provides a new road bridge under the railway and the canal to the west of the existing Ashtown Level Crossing along the line of the Mill lane facilitating new vehicular road.
Coolmine Level Crossing
The Emerging Preferred Option provides a new road bridge over the railway line and canal connecting to the north of St. Mochta’s Grove and Station Court and to the south of the Riverwood Court Road. A new standalone pedestrian and cycle bridge will be provided over the railway line immediately adjacent to Coolmine Station.
Porterstown Level Crossing
The Emerging Preferred Option provides a new pedestrian and cycle bridge over the rail at the existing crossing. Vehicular traffic will utilise the existing local road network including the Diswellstown Road (R121 at Dr. Troy bridge).
Clonsilla Level Crossing
The Emerging Preferred Option provides a new pedestrian and cycle bridge over the railway to the west of the existing level crossing. Given the low traffic flows utilising the level crossing, combined with the proposed new road bridge at Barberstown to the west and the Diswellstown Link Road to the east of the crossing, the optimal solution has been determined as providing a pedestrian and cyclist bridge.
Works required at existing rail overbridges
Rail overbridges at Castleknock and Broombridge have been identified as having insufficient clearance to accommodate the overhead electrical equipment a number of options are currently being considered at these locations such as bridge modifications which are subject to further studies. All other bridges along this section are currently being assessed to confirm clearances and required works at those locations.
Clonsilla Station to Maynooth Depot
Between Clonsilla Station and the proposed depot the existing rail line continues parallel and to the north of the Royal Canal, passing through Leixlip Confey Station, Leixlip (Louisa Bridge) Station, and Maynooth Station.
In this section of the scheme there are two existing level crossings which have been identified for closure at Barberstown and Blakestown.
Barberstown Level Crossing
The Emerging Preferred Option provides a new road bridge over the railway line and canal, south of the current level crossing and connecting the existing R121 to the east of the rail to the Barberstown Lane to the west of the rail line.
Blakestown Level Crossing
The Emerging Preferred Option is not to provide replacement infrastructure following the closure of the level crossing. Access and diversions will be via the local road network and R449 to the east of the crossing.
Works required at existing rail overbridges
Rail overbridges such as at Jackson’s Bridge (a protected structure) on the L5041 road west of Maynooth has been identified as having insufficient clearance to accommodate the overhead electrical equipment. Options are currently being considered such as bridge modification. which is subject to further studies. All other bridges along this section are currently being assessed to confirm clearances and potential works required at those locations.
Depot west of Maynooth
Between Maynooth and the proposed depot the current single-line tack will be upgraded to a double-track section. This new track will be located to the north of the existing single line track and the south of the Royal Canal. The proposed depot will be located to the west of Maynooth and south of the rail line and canal. It will be used for train maintenance and stabling.
The proposed depot will comprise a main depot building and maintenance shed, office and administrative building, train washing and cleaning facilities as well as other maintenance facilities. It will include a test track, stabling for trains, storage, an electrical substation, staff parking and facilities for staff.
Depot Access Route
The Emerging Preferred Option for providing access to the depot utilises the existing road network for the majority of route with only minor modifications required.
The access will be from the R148 which will require the demolition of the existing private agricultural over bridge (OB24) and the construction of a replacement wider bridge over the double tracks to facilitate vehicular access. The proposed bridge enables a new connection to the R148 crossing the Royal Canal and the rail line providing the required access to the proposed depot.
Clonsilla Station – M3 Parkway
West of Clonsilla Station the line splits with a line continuing out towards Maynooth and a line to M3 Parkway. The M3 Parkway line spurs northwards passing through Hansfield Station and Dunboyne Station before terminating at M3 Parkway Station which lies to the north of Dunboyne and west of Junction 5 off the M3 Motorway.
The line will be electrificfied, through the installation of overhead electrical equipment, associated upgrades of signals and communications, and the provision of electrical substations as required.
A number of rail bridges are currently being assessed to determine the options available to provide the required clearance for the overhead electrical equipment.