UK transport body Crossrail has awarded four tunnelling contracts worth a total of £ 1,2 billion (€ 1,5 billion), marking the first step in what is said to be the largest infrastructure project in Europe.
Nearly 21 km of twin-bore tunnel will be constructed underneath central London for Crossrail, which is owned by Transport for London, the government body responsible for the capital's transport system.
Tunnelling activity will start in late 2011 with the first of seven tunnel boring machines (TBM) starting work in spring 2012.
The initial "Western running tunnels" contract was awarded to a joint venture comprising BAM Nuttall, Ferrovial Agroman (UK) and Kier Construction. This project is planned to link Royal Oak tube station in west London to Farringdon, near the centre, with 6,2 km of tunnel.
BAM, Ferrovial and Kier also won a contract for early access shafts and sprayed concrete lining works along the tunnel linking Bond Street and Tottenham Court Road stations.
Later in 2012, two further TBMs will head from the Docklands in East London to the city Centre, with further, shorter, tunnel drives planned in the Royal Docks and east London.
These "Eastern Running Tunnels" contracts consist of an 8,3 km tunnel running from Limmo Peninsula to Farringdon, a 1 km tunnel from Limmo Peninsula to Victoria Dock and a 2,7 km tunnel linking Stepney Green to Pudding Mill Lane. A joint venture comprising Dragados and John Sisk & Son won this contract.
A fourth contract for early access shafts and sprayed concrete lining works for the tunnels linking Whitechapel and Liverpool Street stations was awarded to a joint venture comprising Alpine BeMo Tunnelling, Balfour Beatty Civil Engineering, Morgan Sindall and VINCI Construction.
The tunnels will be 6 m in diameter, and each TBM will be up to 120 m in length.
The Western and Eastern running tunnels will have tunnel portals at Royal Oak, Pudding Mill Lane and Victoria Dock, and construction of the tunnel portal at Royal Oak is underway now.
Crossrail said the TBMs will be purchased by the main tunnels contractors from European manufacturers, noting that there are no UK-based companies that manufacture TBMs.
Rob Holden, Crossrail's chief executive, said the company had reached a "very significant milestone" with the award of the main tunnel contracts.
"The value of the contracts, combined with the length of tunnel to be constructed, is on a scale not seen in the UK since the Jubilee Line Extension or the Channel Tunnel Rail Link," Mr Holden said.
The four contracts are the first of nearly 30 that will be awarded by Crossrail over the next 18 months. A further series of tunnelling contracts will be awarded in 2011 including the 2,6 km Thames Tunnel between Plumstead and Woolwich, and remaining contracts for tunnel portals and station platform tunnels.