More than £115m was spent on Crossrail 2 before work on the scheme for a new north-south rail line through London was suspended in November.
The costs for the development and design of the line, which was once hoped to be operational in the early 2030s, were shared between the Department for Transport and Transport for London.
However, work was officially paused as part of the emergency financial agreement between the government and TfL to fund the capital’s transport network after passenger revenues dried up due to the coronavirus pandemic.
Around a quarter of the money spent went to Network Rail, the state-owned railway infrastructure manager, according to figures revealed by New Civil Engineer.
The biggest private sector beneficiaries were Arup, whose design consultancy work on the tunnels and southern section totalled almost £12m, and Arcadis, which was paid £11.4m for engineering consultancy.
The line would have linked stations in the home counties to the north and south-west of the capital via new tunnels underneath central London, roughly along the route of the Chelsea-Hackney underground line first discussed in the 1970s.
Central development funding was allotted from 2015-16 when construction of the original Crossrail line appeared to be on time and on budget, and when Crossrail 2 was regarded as an essential part of the plan for handling HS2 passengers arriving in London Euston – a prospect that is in doubt.
The division within TfL that was working on Crossrail 2 was seconded to other work after Covid-19 hit London last year. TfL said that while the project was mothballed, land would remain safeguarded and the design work would remain relevant.
A TfL spokesperson said: “The pandemic, and subsequent impact on our finances, has meant that we have to be realistic about what is currently affordable.”
A planned Bakerloo line extension for the underground is also on ice.
The spokesperson added: “Our immediate priority for these schemes is progressing safeguarding as they are still likely to be needed in the future to support long-term growth and modal shift in London. The work developing proposals for these schemes will still be used when we are in a position to confirm funding in future.”