Environment
TBM Makes First Thames Tideway Breakthrough
Project on schedule for 2022 completion, but already 8% over budget

London's super sewer cleanup, designed to clean up the river Thames marks progress with first tunnel hole-through.
Photo Courtesy Thames Tideway
With construction costs now 8% over budget, London’s 25-kilometer the Thames Tideway joint venture contractor completed the first tunnel breakthrough this month, with construction still on course for on-time completion in 2022.
The breakthrough by the team of Balfour Beatty, Morgan Sindall and BAM Nuttall completed the 1.1-km-long, 2.6-m-dia spur between Wandsworth and Fulham.
Elsewhere, three of four larger TBMs are driving the main 6.5-7.2-m-dia east-west tunnel from Acton to Abbey Mills, with the fourth machine due to start next year. Bazalgette Finance plc., the private sector project owner, now puts the construction cost at $4.9 billion.