Thames Tideway

Ferrovial Agroman and Laing O'Rourke JV
£4.2 billion GBP
March 2016 — ongoing
Services performed
Review of the current design of the connection between sprayed concrete lined connection tunnels and the main (TBM) tunnel with the aim to propose efficient alternatives.
The Thames Tideway Tunnel is an under-construction 25km tunnel running mostly under the tidal section of the River Thames through central London. It will provide capture, storage and conveyance of almost all combined raw sewage and rainwater that currently overflow into the river. Once constructed, the main tunnel will have an internal diameter of 7.2m and will run from -30m at Acton, West London for over 25km under central London down to -70m at Abbey Mills in the East. It will connect 34 of the most polluting combined sewer overflows (CSOs), via transfer tunnels. The tunnel will transfer the captured sewage to the Stratford to East Ham part for onward delivery to Beckton Sewage Treatment Works.
The geology transitions from West to East through London Clay, into the complex Lambeth Group (clay, sand and gravel strata) into Thanet Sands, before giving way to the Chalk including flints.
London, GB


  • Challenging the base design, carrying out a detailed structural feasibility study aiming to improve safety, save construction cost and time.
  • Supporting the contractor with efficient structural and waterproofing design solutions.

New shaft, connection and main tunnel structures (Courtesy Tideway)

Isometric of connection between SCL and TBM tunnels