Railtrack's plan to integrate London's Tube with the national rail network present some serious technical challenges which could undermine the financial viability of the project. Matthew Jones reports.
Deputy Prime Minister John Prescott's announcement last week that the main line railway could be joined to the shallow sub surface lines of the Underground under a deal with Railtrack was welcomed by the business community in London. The agreement clears the way for other consortia to bid for the two packages for the privately financed upgrade of London Underground's deep Tube lines.
At face value there appears to be a strong logic to the initiative. It seems to fit with the Government's wider policy of integrating different modes of public transport. In theory it means that commuters will - for instance - be able travel into London and around parts of the Metropolitan and Circle Lines without having to get off their trains and onto the Tube.
Whether it is really feasible has still to be demonstrated. There is a suspicion that Railtrack is less interested in delivering a 'joined up' commuter network than it is in getting its hands on part of the Tube. Any profits it makes from the Tube upgrade are likely to be outside the control of the Rail Regulator, as are those it will earn from running the Channel Tunnel Rail Link.
An accurate shopping list of the civil engineering work needed to allow main line commuter trains to mix with Tube trains on the Underground has still to be worked out. Some rail engineers doubt Railtrack's own technical understanding of the proposal. Though the deal has been billed as providing a cheap alternative to projects like the shelved CrossRail scheme between Paddington and Liverpool Street, sources with in depth knowledge of the Tube say the cost could still spiral into 'billions.'
Railtrack for its part is keeping its cards close to its chest while negotiations with the Government continue. It will confirm only that the Great Western Line will be joined to the Tube at Paddington, and that there will be other links from the East London Line north to Finsbury Park and South to Croydon and Gatwick.
The Government hopes that by missing out the tendering process and negotiating direct with Railtrack it will be able to sign off the public private partnership for the sub surface lines by the original target date of April 2000. But it has an awful lot of engineering questions to answer before then. See over