Service 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.
Geology description
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.
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.
