Set to be the biggest infrastructure project ever undertaken by the UK water industry, the Thames Tideway Tunnel will modernise London’s Victorian wastewater infrastructure, dramatically improving the water quality of the River Thames and give London a wastewater system it can rely on for the next 100 years.

AECOM will deliver design services for the tunnel’s 12-km central, and largest, section. The entire 25-km tunnel generally follows the route of the River Thames, connecting to overflows along the riverbanks. The complex central section of the tunnel will pass through a variety of different ground conditions, including London Clay, Lambeth Group, Thanet Sands and Chalk. There are a total of 26 shafts, drop, vortex and connection shafts plus tunnel boring machine launch shafts, with shaft depths varying between 10 and 70 metres. It will be built under London’s existing underground infrastructure, in close proximity to tube lines and utilities. The designs will also need to minimise disruption to the busy, compact London streets above, and will involve a complex programme of geotechnical instrumentation monitoring.


Patrick Cox