The East London line extension (ELLX) project was a British railway engineering project in London, managed by Transport for London. The project involved extending the East London Line (formerly part of the London Underground network) and making it part of the mainline London Overground network. This was done by re-opening sections of disused railway line and by converting track electrified by the third-rail system, signalling, lineside signage and communication systems, etc. to mainline standards. New rolling stock was introduced and four new stations built along the route, with a fifth scheduled to be added in the future at .
The work, which cost around £1 billion, began in 2005 and was carried out in two phases. The first phase was completed on 23 May 2010 with a service from via the historic Thames Tunnel under the River Thames and along part of the Brighton Main Line to West Croydon and . Trains also go to , where they make a connection with the South Eastern Main Line. On 28 February 2011, the line was connected at its northern end to the North London Line at Highbury & Islington. In the second phase of the project, on 9 December 2012, a branch was connected to the South London Line enabling services to run to .
Project overview
Phase 1
Phase 1 of the ELLX project involved the extension of the original line at its northern and southern ends. The northern extension runs from to , connecting with the North London Line; this section became operational as far as in late May 2010, and to Highbury & Islington on 28 February 2011, with trains every five minutes on the central section between Dalston Junction and Surrey Quays. The southern extension of phase one from to and West Croydon was completed simultaneously with that to Dalston in 2010, and a full service began in May 2010.
The northern extension makes use of disused trackbeds on the Kingsland Viaduct that formerly carried the North London Railway branch to Broad Street station, which was closed to the national rail system in 1986. It bypasses station, which closed permanently in June 2006. The new line diverges before reaching Shoreditch station, traverses the former site of the Bishopsgate Goods Yard and crosses Shoreditch High Street on a bridge before running north along Kingsland Viaduct. Four new stations have been built at , , and . From there, the double-track line continues under Kingsland High Street and Boleyn Road, and then parallels the existing North London Line with services running through (for interchange with the North London Line eastbound) to (for interchange with the Victoria line, North London Line westbound and Northern City Line).
The stations between New Cross Gate and Crystal Palace/West Croydon were previously managed by Southern, which ran all train services to these stations before they were later transferred to TfL control.
The existing section of line was completely overhauled; all of the tracks were replaced and signalling was upgraded to Network Rail standards.
Phase 2
The ELLX Phase 2 project extended the line from Surrey Quays to the Network Rail South London Line. Trains on this route run to via , , , and . From Wandsworth Road, instead of running to Victoria, westbound trains branch off at Factory Junction and pass through Battersea towards Clapham Junction.
After a period of uncertainty, funding for this phase was announced in February 2009 with a prospective completion date of May 2012, in time for the start of the 2012 Summer Olympic and Paralympic Games, which were held in London in July 2012. TfL, however, postponed the opening date to 9 December 2012.
A new station at was proposed. In September 2010, funding for this was refused by the Department for Transport but the developer Renewal later agreed to fund it as part of its Surrey Canal development scheme, which was due to start in 2013, and Lewisham Council granted planning permission. The new station was planned to open in 2015, depending on the pace of new housing development in the vicinity.
At Clapham Junction, former Platform 2 was divided into two staggered platforms; Platform 1 for the existing Overground services to/from Willesden Junction and Stratford, and Platform 2 for the new services to/from Highbury & Islington. In addition, a disused staircase at Platform 2 was brought back into use and a new lift was installed to improve access from the newly refurbished Grant Road entrance.