Water & wastewaterWastewater infrastructure, storm sewage tunnel

Thames Tideway Tunnel - Central Section

Central London (Fulham to Bermondsey) · 2016-2025 (Overall project construction 2016, Tunnelling up to 2022, Completion 2025) · £1.5bn (Central section) [1]

The judgement call

Account-gated at launch

Collaboration with client, JV partners, and London authorities [2] - Fabricating significant elements off-site (steel reinforcement cages, precast panelised river walls, large hydraulic installation) [2] - Extensive use of digital engineering and modelling (BIM) [2] - Use of virtual reality (VR) for safety, quality, and STEM education [2] - Consistent approach to design optimisation and value engineering [1] - Use of the River Thames for transport and logistics to minimise road movements [1]

Key engineering challenges

Delivering heavy civil engineering, tunnelling, and complex marine infrastructure on space-limited sites in a busy capital [2] - Constructing a 3,700-tonne concrete and steel culvert, floated into position under the Grade II listed Blackfriars Bridge, just 7m above the Waterloo & City tube line, and in proximity to a gas main and service tunnels [2] - Managing logistics and soil disposal via barges on the river [1]

Project facts

Client / owner: Tideway
Lead contractor: Ferrovial and Laing O’Rourke (Joint Venture) [1] [2]
Lead designers: Jacobs (Program Manager for overall project) [3]
Project type: new build
Scale: 12.7km tunnel length (Central section) [1]; 8.8m diameter (TBMs) [1]; up to 60m deep [1]
Disciplines: Civil; structural; geotechnical; mechanical; electrical; environmental; tunnelling; marine infrastructure
Standards & frameworks: CDM Regulations; NEC4 (implied); Environmental Agency regulations

Sources: Ferrovial: https://www.ferrovial.com/en/business/projects/thames-tideway-tunnel-central-section/ (Accessed: 2026-06-10) - Laing O’Rourke: https://www.laingorourke.com/projects-and-sectors/united-kingdom/tideway/ (Accessed: 2026-06-10) - ICE: https://www.ice.org.uk/what-is-civil-engineering/infrastructure-projects/thames-tideway (Accessed: 2026-06-10)

Discuss this project in Roots Back to the Vault