Owner
Tideway
Client
Ferrovial Agroman and Laing O'Rourke JV
Cost
£4.2 billion GBP
Timeframe
October 2018
— December 2018
Services performed
CAT3 checking of primary and secondary linings of main and connection tunnels at six tunnel junctions. The check included elements of the temporary works: dewatering, pipe arch pre-support and face stability.
Description
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.
Geology
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.
Location
London, UK
Highlights
- UK'S HIGHEST LEVEL OF DESIGN CHECKING FOR HIGH RISK ELEMENTS
- CHALLENGES WITH TUNNEL CONSTRUCTION WITH SOILS OF THE LAMBETH GROUP
- CHECKING OF TUNNEL CONNECTIONS BETWEEN PRECAST CONCRETE AND SPRAYED CONCRETE TUNNEL LININGS
New shaft, connection and main tunnel structures (Courtesy Tideway)
Isometric of connection between SCL and TBM tunnels