EngTree
Water & wastewater
Water & wastewaterWastewater infrastructure, storm sewage tunnel

Thames Tideway Tunnel - West Section

West London (Acton to Wandsworth) · 2016-2025 (Construction 2016, Tunnelling 2018-2022, Completion 2025) · £416 million (West section JV) [3]

The judgement call

Account-gated at launch

Use of Building Information Modelling (BIM) for construction simulation and planning [4] - Implementation of lean construction, collaborative planning, and continuous improvement techniques to manage costs and schedule [2] - Development of a transformational health and safety approach, building on best practices from London 2012 Olympics and Crossrail [2]

Key engineering challenges

Constructing a large-diameter tunnel beneath a complex urban environment with existing utilities and London Underground lines [2] - Managing ground conditions including chalk and clay [3] - Minimizing disruption to local residents and river traffic during construction [2] - Transporting excavated spoil by barge to reduce road congestion and emissions [2]

Project facts

Client / owner
Tideway (on behalf of Thames Water customers)
Lead contractor
Balfour Beatty, Morgan Sindall, BAM Nuttall (Joint Venture) [3]
Lead designers
Jacobs (Program Manager) [2]
Project type
new build
Scale
7 km tunnel length (West section) [3]; 7m diameter [3]; 66m deep [3]
Disciplines
Civil; structural; geotechnical; mechanical; electrical; environmental; tunnelling
Standards & frameworks
CDM Regulations; NEC4 (implied by UK infrastructure projects); Environmental Agency regulations

Sources: Tideway: https://www.tideway.london/ (Accessed: 2026-06-10) - Jacobs: https://www.jacobs.com/projects/thames-tideway-tunnel (Accessed: 2026-06-10) - ICE: https://www.ice.org.uk/what-is-civil-engineering/infrastructure-projects/thames-tideway (Accessed: 2026-06-10) - Balfour Beatty: https://www.balfourbeatty.com/what-we-do/projects/thames-tideway-tunnel/ (Accessed: 2026-06-10)