Railtrack reshapes Thameslink 2000
With a £600m upgrade of the north - south link through London underpinned by contractual agreements, Richard Hope asked Chris Jago, Director of Railtrack's Southern Zone, how the project is taking shape
EXACTLY FIVE YEARS ago this journal described how a recently re-opened line across the centre of London was to be upgraded to raise the capacity from six trains/h to 20 or 24 in each direction (RG 1.92 p37). The intention had been to mark the depositing in November 1991 of a Bill to construct extra tracks to raise peak-hour capacity on connecting lines at the southern end of the cross-city link.
In the event, the Thameslink 2000 project was put on a back burner, the Bill having been withdrawn at the last moment on government orders in favour of the far more costly east - west CrossRail. In 1996, the government reversed the order of the two projects in the queue for funding, moving T2000 to the front along with the Channel Tunnel Rail Link. These Siamese twins are inseparable because T2000 requires a new station box to be built underneath extended platforms at St Pancras, the CTRL terminus, and the quantities of international and domestic passengers that CTRL will carry need T2000 to distribute them without overloading London Underground.
Back in 1991, the T2000 upgrade was promoted by British Rail's Network SouthEast business which assessed the benefit/cost ratio at a healthy 3:1. Had the project gone ahead, BR would have obtained the cash for the infrastructure works from government in the form of loans or grants. As electrification is at 25 kV 50Hz north of London and 750V DC third rail in the south, additional dual-voltage trains would have been ordered as part of the overall EMU fleet renewal process.
With the advent of privatisation, the process is different. Responsibility for implementing T2000 lies with Railtrack, and in particular with Chris Jago, Director of its Southern Zone which is leading on the project. Although the Transport Secretary Sir George Young announced the go-ahead for T2000 on February 27 1996, two days before the CTRL concession was awarded to London & Continental Railways, it rests on agreements signed in April by Railtrack, the Office of Passenger Rail Franchising, and the Department of Transport. These in turn were linked to the restructuring of Railtrack's balance sheet in the run up to the successful flotation of the company in May, and to DoT's concession agreement with LCR.
Jago explains that Railtrack has agreed to spend some £600m on works required to bring T2000 into being, mainly in central London but also at stations 100 km or more from the capital where platforms may have to be lengthened for 8 or 12-car trains. Although Fig 1 is no more than indicative of the service pattern likely to be provided when T2000 is finished, it shows how widely the trains are expected to range. Start of construction is still two or three years off, and in the meantime what Jago calls 'three caveats' must be resolved:
- First, Railtrack must secure powers under the 1992 Transport & Works Act to carry out the works. T&W procedures have replaced Parliamentary Bills, but there is limited experience - not all of it happy - of using this route to obtain powers for substantial railway projects. Railtrack is already preparing its application, which requires extensive consultation with parties affected by the works. Jago expects to start the T&W process this summer and hopes to complete it within 18 months - that is, by the end of 1998; but he cautions that 'T&W procedures are not yet tried and tested.'
- Second, the Regulator (and in the event of an appeal, the Transport Secretary) must agree formally to the closure of the short spur from Farringdon to Moorgate in the City of London. It is impossible to implement T2000 as planned with 12-car trains unless the junction at Farringdon is eliminated.
- Third, LCR must be committed to construction by a specific date of a cut-and-cover station box at St Pancras at cost of around £100m, which has to be phased with CTRL works in this area.
Although DoT is giving LCR the £100m as a grant, construction is still dependent upon LCR raising the necessary capital to build the CTRL on the money markets. This may be achieved in 1997-98, but the outcome is not certain. The CTRL Bill must also receive Royal Assent since it includes powers for a new connection from Thameslink to the East Coast main line out of King's Cross, but this is expected very shortly.
OPRAF underwrites paths
Aside from any incidental income from property development or station trading, Railtrack must rely on track access charges paid by franchised passenger train operators using Thameslink to reward its £600m investment.
Jago explains that 'OPRAF has agreed to underwrite the paths Railtrack must provide in a way that gives a reasonable rate of return.' The agreement with OPRAF calls for 24 paths per direction in peak hours, splitting south of Blackfriars so that 18 trains pass through London Bridge and six go via Elephant & Castle. Equivalent off-peak paths are 14+4.
At a point in time which is not defined, Railtrack must give three years' notice to OPRAF of its intention to have T2000 ready for service. From that point onwards, Railtrack is committed to that date and must pay a penalty for missing it. This gives OPRAF three years in which to negotiate, or renegotiate, franchises to fill up the available paths at the agreed level of track access charges from Day One.
OPRAF's guarantee lasts for 14 years from Day One, by which time the investment should have been paid off. Loans that are amortised over the 14 year period are likely to form part of the financing package put together by Railtrack. This begs the question as to when Day One is likely to arrive. Jago suspects that 'it will take seven or eight years from now' and will therefore be 'not much before 2003, to be realistic.' A likely scenario might therefore see T2000 and the CTRL opening at about the same time in 2003-04.
Works still being defined
In terms of engineering, the current proposals are mostly similar to those of 1991. There are also a number of decisions still to be taken, such as the track layout through the reconstructed London Bridge area, and the signalling and train control policy.
Working from north to south, threading the connection between Thameslink and the ECML through the complex web of tracks that will join CTRL to St Pancras and the North London line still requires 'a lot of detailed work.' It is LCR's responsibility to build this section, including a grade-separated junction in tunnel with the existing Thameslink route, and close co-ordination between Railtrack and LCR will obviously be essential.
Back in 1991, T2000 was going to use the low-level station planned for CTRL under King's Cross. Since that idea was dropped, T2000 has included new platforms partially under Midland Road on the west side of St Pancras, on the alignment of the present brick tunnel. The existing King's Cross Thameslink station will close, because the platforms are too short and narrow. These platforms are already severely congested with the current service of six trains an hour. The booking hall at street level may be retained as a public entrance to the Underground.
Platforms at Farringdon will be lengthened to 275m for 12-car trains and a new T2000 booking hall constructed at street level independent of the Underground alongside. Good interchange between the platforms will remain. Provision will also be made for interchange with CrossRail when this is built.
Blackfriars will see extensive alteration, with longer platforms spanning the bridge over the River Thames. The aesthetics of the new station are causing a certain amount of debate, notably with English Heritage. Jago says the number of platforms is being reviewed with a view to reducing the cost of access from both sides of the river. Access to the south end of the platforms will probably be by stairs leading directly up from the riverside walk that passes under the railway bridge, with a small booking office under adjacent railway arches. An additional pedestrian bridge crossing the river at high level could be part of the scheme.
The difficult approach to London Bridge station from the west involves constructing a new double-track viaduct on the south side of the existing structure above Borough Market, a densely built-up area. This will be used by Charing Cross trains. At London Bridge, where the through platforms were extended about four years ago to accept 12-car Networker trains, one terminal platform and some railway offices will be lost. This will release space for a fourth island platform, providing eight through tracks: three each for Cannon Street and Charing Cross trains, and two in the middle for T2000.
Five years ago, T2000 was intended to link up with routes now franchised to Connex South Eastern as well as SouthCentral. The South Eastern connection has been dropped because 'the agreement assumes no trains through Kent', although Jago says 'the agreement refers to a template, not an absolute.' South Eastern tracks into Charing Cross will be diverted under the T2000 connection to SouthCentral's main line to Brighton using an existing bridge which spans the disused line into Bricklayers Arms freight depot. A short distance to the south, a new flyover will transpose the T2000 tracks to the centre pair of the four tracks through New Cross Gate, which are used by fast trains.
A fleet of 46 four-car dual-voltage Class 319 EMUs was built for the original Thameslink project in 1988, and later expanded to 86 units of which 20 are leased to Connex South Central and work on 750V DC only - some with their pantographs removed.
The 41 four-car Class 365 EMUs ordered in 1993 are also dual voltage. They are allocated either to West Anglia Great Northern or Connex South Eastern, and will be equipped to work in AC-only or DC-only mode when they finally enter service. These two classes provide the basis of the T2000 fleet. In addition, Connex intends to order 30 more dual-voltage EMUs as it renews old Mk I EMUs under the terms of its 15 year franchise.
At present, the southern (DC) end of Thameslink is controlled from Clapham Junction and the northern (AC) end from West Hampstead. The future control strategy has not yet been worked out in detail, but Jago expects the core of T2000 extending from beyond St Pancras through London Bridge towards Croydon to be supervised from one point.
Given the spread of services north and south of London, it is not realistic to expect trains to be running consistently through the core in the right order; Jago anticipates an element of first-come-first-served working. Even so, tight discipline will be needed to get 24 trains through in an hour, given that they are travelling long distances and passengers will take more time to alight than would be the case with a metro. Given the importance of minimising dwell time, and the fact that trains may turn up in the wrong sequence, high quality passenger information systems are considered essential to the success of T2000.
Automatic train protection will certainly be required, and automatic train operation is also being considered to ensure consistent performance. Transmission-based signalling is currently being developed for the West Coast main line (RG 9.95 p571), and if this is ready in time it may be used for T2000.
At present, the changeover between AC and DC traction takes place while the train is stationary at Farringdon. The final section of third rail which overlaps the AC catenary is isolated from the rest of the DC network, and energised by circuit-breakers which are closed automatically each time a train needs to draw current. They were not designed for this arduous duty, let alone the more intensive service now proposed, and reliability has suffered. Jago's team is reviewing the whole power supply strategy; 'we are looking above all for a highly reliable system.' Extra power will be needed anyway to support 24 trains/h, and it is possible that the AC/DC boundary will be relocated to a more convenient location, maybe even with the changeover taking place on the move between stations as happens at the entry to the Channel Tunnel and on the West London line. Reinforcement of power supplies may be necessary on the main line to Brighton in order to improve performance and cope with more trains; third rail voltage may be increased as has happened on the Channel Tunnel routes.
With so much complicated work to carry out, much of it affecting the most intensively used tracks on Railtrack's network, some disruption to existing services is inevitable. Jago says a 25 week blockade will be required by LCR to break open the tunnel alongside St Pancras and construct the new station box. During this time, Thameslink trains will probably terminate at Blackfriars and St Pancras, with work proceeding at many points in between. The most difficult problems over disruption are likely to arise in the London Bridge area.
Jago says diversion of trains to Victoria and other termini will help, but he points out that Railtrack's other infrastructure work such as renewal of signalling controlled from Dartford must continue as well. All these projects react with each other, just as CTRL construction will affect lines in Kent as well as around St Pancras. As Jago sees it, 'the biggest challenge we have got is to minimise the damage to the fare-paying passenger.' o
- CAPTION: Thameslink 2000 will require reconstruction of Blackfriars station onto the bridge across the Thames, but English Heritage is concerned about the view of St Paul's Cathedral (left of picture)
- CAPTION: Thameslink's inner suburban services connect with those of SouthWest Trains at Wimbledon
- CAPTION: Fig 1. An indicative service pattern for Thameslink 2000 was included in the Railtrack-OPRAF agreement to show how services may fan out across southeast England
- CAPTION: Thameslink's existing fleet of 160 km/h Class 319 EMUs can make full use of its capability on the Midland Main Line between London and Bedford
- CAPTION: Last EMUs ordered by BR, the 41 Class 365 Networker Express units, were designed as dual-system for possible use on Thameslink 2000; at present they are leased to 25 kV-only WAGN and 750V DC-only Connex South Eastern
Railtrack definit la ligne Thameslink 2000
Des accords conclus en 1996 avec le Directeur des Concessions et le Ministère des Transports ont permis à Railtrack d'aller de l'avant avec son projet de transformer une vieille ligne à travers le centre de Londres en une route pour voyageurs journaliers de haute capacité avec des capitaux privés. Bien que cette ligne ait été remise en service avec succès en 1988, Thameslink demande d'importants travaux d'ingénierie pour que son plein potentiel de services à travers Londres soit complètement exploité
Railtrack definiert Thameslink 2000
Durch die im Jahre 1996 mit dem Franchising-Direktor und dem Verkehrsministerium getroffene übereinkunft ist es Railtrack nun möglich, ein Projekt voranzutreiben, das die Umwandlung einer alten, durch das Londoner Zentrum verlaufenden Strecke in eine Hochleistungspendlerstrecke unter Verwendung privater Gelder vorsieht. Zwar wurde Thameslink 1988 für den Betrieb erfolgreich instandgesetzt, doch sind noch erhebliche Konstruktionsarbeiten erforderlich, bis ihr ganzes Potential für Reisen quer durch London völlig ausgenutzt werden kann
Railtrack define Thameslink 2000
Los acuerdos alacanzados durante 1996 con el Director de Franquicias y el Ministerio de Transporte han permitido a Railtrack ir adelante con el proyecto para convertir una vieja línea que atraviesa el centro de Londres en una línea de transbordo urbano de alta capacidad mediante capital privado. Aunque Thameslink fue restaurado con todo éxito en 1988, se necesitan obras de ingeniería de importancia para poder explotar todo el potencial de viajes translondinenses