Complementary to Crossrail 1, this is a mainline tunnel from Clapham Junction via Victoria, Tottenham Ct Rd & King's Cross to undecided lines in the northeast.
Also known as the Chelsea-Hackney Line.
The previous project
Aside from Crossrail, the major project planned for the last couple of decades but not yet brought to fruition was the Chelsea-Hackney Line. This was to be a tube line linking two of the remaining areas of inner London without Underground lines. A line would have run from Wimbledon up the District line branch to Putney Bridge, where it would have gone underground via Chelsea King's Road, Sloane Square, Victoria, Piccadilly Circus, Tottenham Court Road, King's Cross, Highbury, Dalston and Hackney. It might then have travelled along the North London Line to North Woolwich or to Stratford and then up to Epping, taking over the Central Line beyond Woodford.
An alignment through London was safeguarded but is now likely to be scrapped, to be replaced by Crossrail 2.
The current project
It is now recognised that greater benefits can be achieved by increasing the scope of the project, and Cross London Rail Links (CLRL) has taken the project on board as Crossrail 2.
The core tunnel has been rerouted to run from Clapham Junction to Victoria, Piccadilly Circus, Tottenham Court Road and King's Cross. Outside this central segment, Crossrail 2 services would replace various National Rail suburban services in order to free up capacity at terminals like Victoria, Waterloo, King's Cross and Liverpool St.
For example, trains might run from Hampton Court via Wimbledon, through the tunnel to King's Cross and a further tunnel to Hackney, and then to Stratford and up the Lea Valley - one of the GLA's major regeneration objectives.
Piccadilly Circus is not a "definite" station due to the constraints upon construction of a large-scale Crossrail 2 station in the area. A station can only be built here if Crossrail 2 is built to Tube standards; that would make the whole project cheaper (smaller tunnels) although it would have to use smaller trains.
At the southern end, Victoria is definite; the route south of there is not. Trains would almost certainly serve Clapham Junction in some way; the route between Victoria and Clapham Junction could be via Battersea (to serve the new development at Battersea Power Station) or via the King's Road in Chelsea and Imperial Wharf station. The former would have big advantages for the power station developers; the latter would serve an area of Kensington & Chelsea currently poorly served by public transport.
One possibility that has been floated for the northern end is to serve the dismantled Alexandra Palace railway from King's Cross. Trains would run to Finsbury Park, then up this route to Highgate, where they could then take over Northern Line services to High Barnet, or run to Mill Hill East and then continue along a route that was originally going to be built in the 1930s - to Mill Hill (The Hale) and then Edgware. Either way, overcrowding relief would be delivered to the Northern Line.
Crossrail 1 is already projected to serve Heathrow and possibly London City. Crossrail 2 could also serve Heathrow with a short connection in the vicinity of Feltham (sometimes known as Airtrack), thus improving access to Heathrow from south London.
There is also potential for Crossrail 2 to serve Stansted. This would mean that all 5 major London airports would be served by cross-London services (Crossrail 1 & 2 and Thameslink 2000), enabling all transfers to take place with a maximum of one interchange.
Such a link would either run from Hackney up the Lea Valley, or would use a new alignment from Epping past Harlow to reach the railway to Stansted.
The latter link was floated as part of the London to Ipswich multi-modal study (LOIS), along with a link from Epping to Chelmsford. The Epping-Stansted link would help support the government's objective to build thousands of new homes in the M11 corridor. (See a PDF map of the LOIS proposals.)
Crossrail 2 has even more scope to relieve pressure at London termini and on the Underground than Crossrail 1 does at Paddington, Waterloo, London Bridge and Liverpool St.
For Crossrail 2, relief would occur primarily at Victoria, Waterloo, and King's Cross (already to be relieved partially by Thameslink 2000). Further relief could occur at Liverpool Street and Moorgate, and, depending on the chosen route, Fenchurch St.
On the Underground, the Victoria Line would receive the biggest benefits in reduction of overcrowding. The Bakerloo, Northern and Central lines could also see substantial benefits.
Shoreditch Central Line
Crossrail 1 will relieve some congestion on the Central Line; Crossrail 2 could relieve it considerably more if it takes over the route from Leytonstone to Epping. This could allow the construction of an interchange station on the Central Line at Shoreditch High Street with the expanded East London Line, allowing single-change journeys from northeast London to inner south London.
No current news for this project.
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