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A new $32-billion railroad project under central London secured U.K. government approval October 5. Seven years' construction of the Crossrail project, including 41.5 km of tunnels, is scheduled to start in 2010.
Under development since the early 1990s, the 118.5-km-long Crossrail system will link surface networks either side of London with twin, 6-m-dia bored tunnels. It will be Europe's largest civil engineering project, claims an official at the Department for Transport.
Cross London Rail Links Ltd., the sponsor, aims to start procuring construction contracts from next year. Work on Crossrail will overlap with the last two years' effort on London's Olympic sites for the 2102 Games.
With other major infrastructure jobs winding down, U.K. contractors will have enough capacity to handle Crossrail, claims John Wilson, technical director of the Civil Engineering Contractors Association. Working in the congested city, logistics will be the biggest problem, he adds.
CLRL, owned by Transport for London and Department for Transport, has four design firms working on the tunnel sections and one on surface stretches. They are led by CLRL's development manager Bechtel Inc. San Francisco.
As now planned, nine TBMs will drive the tunnel from four access points. They will work in mainly good clay along the western 6 km. But earth pressure balance machines will be needed in eastern drives.
Ground in the eastern drives includes water pockets, gravel, lignite and fissured clay. Few tunnels were built in that area till the Jubilee Line Extension and the Channel Tunnel rail in the last decade.
Funding for the project will come from the government, Transport for London and the private sector. This week, the City of London Corporation committed $400 million and pledged to raise another $300 million from businesses. The government will announced detailed finding plans next Tuesday.