Engineers and up to 2,000 workers in London have been stitching together and modernizing sections of three 19th-century urban railroads—two defunct and one live—to close a gap of under 3 km in the northeast corner of the city’s emerging orbital route.
Over $1 billion is the expected end cost for the three-year project extending and improving this short stretch of Victorian-era infrastructure in the crowded metropolis. “It is a very complex project because here you are dealing with old Victorian [viaduct] arches,” says Ashok Kothari, a board director of Parsons Brinckerhoff Inc., New York City. Kothari heads program management for the owner, Transport for London (TfL).
“In the U.S., they probably would have demolished the whole thing and built a new one,” says Kothari. “Trying to keep the heritage…is a good thing in my book.” It also has caused construction challenges to abound all along TfL’s project to extend its East London Line (ELL).
The Balfour Beatty-Carillion Joint Venture (BB-C) is replacing track and equipment along 7.5 km of the existing ELL from New Cross, south of the River Thames, to Whitechapel. It includes the twin 365-meter-long river crossing, completed in 1843 as the world’s first tunnel under navigable water. The tunnels were relined and retracked 12 years ago.
ELL crosses the mid-19th-century-era Bishopsgate Goods Yard, about 1.1 km northwest of Whitechapel. About a third of this section is all new; the rest is upgraded with new track and systems.
Covering nearly 5 hectares, the goods yard was the project’s most controversial element. Challenges by conservationists, including the official English Heritage, over how much of the yard’s historic brick viaducts should be torn down raged for many months about six years ago.
Until now, ELL terminated in the Bishopsgate area. Extending it about 2.7 km north to Dalston Junction is the main goal of the project. Near Dalston, ELL will connect to an existing urban line across north London, serving the 2012 Olympic Games site at Stratford.
Completing the project in under three years by next June will require fast-track work, “and we did not really get started until February or March 2007,” says Adam Stuart, BB-C’s construction director. Although Kothari says the team is still on schedule, he adds, “A lot of work needs to be done.” BB-C has about 10% of the construction and half the systems to do, he says.
To extend the line to Dalston, the viaduct containing 170 brickwork arches in Kingsland is being revived after sitting unused for more than 20 years. “The old viaduct was leaking and had a lot of rubbish on top,” says Martijn Donders a senior engineer with TfL’s technical adviser Mott MacDonald Group, London.
Taylor Woodrow Construction, Watford, completed the viaduct’s refurbishment plus construction of 22 bridges along its length in 2006 under a $50 million contract with TfL. To link ELL and the restored Kingsland arches, BB-C has built a tightly curving, 175-m-long concrete viaduct from the goods yard.
The new link includes a 35-m-long span bow-string arch bridge over Shore-ditch High Street. It was placed in March 2008 with a 1,200-tonne-capacity crane, the U.K.’s. largest, according to Mott MacDonald. That placement went...