Thames Tideway Tunnel, Central Section

The Thames Tideway Tunnel is the largest infrastructure project ever undertaken by the UK water industry. It is essential to tackling overflows from London’s Victorian sewers into the Thames for at least the next 100 years. The project will create over 4,000 sustainable jobs and another 5,000 indirectly. It will also offer hundreds of local apprenticeships and work placements, leaving a lasting legacy in the heart of London.

London’s sewerage system relies on a series of combined sewer overflows, designed to discharge into the Thames during heavy storms. This system releases sewage into the river on a weekly basis, reaching over 55 million tonnes annually. We are delivering the central section while working alongside two other contracting teams in the west and east. Our scope includes development consent, design, and construction of the new sewer tunnel.

With a total length of 12.7km, the central tunnel will be driven using two purpose-built 8.8m diameter Earth Pressure Balance (EPB) TBMs, and will run up to 60m deep between Fulham and Bermondsey. In addition, the works include the construction of eight shafts and pumping stations, logistics, and soil disposal via the barges on the river.

Collaboration is a key factor for successful delivery. We have established a Procurement Alliance, in collaboration with Thames Water, the different Main Works Contractors, and the System Integrator (Amey) to ensure that a best-for-project approach is consistently followed. This effective approach to risk management and mitigation ensures that the project is delivered to the highest standards.

Added Value

• Consistent approach to design optimisation and value engineering to reduce cost and improve efficiency
• Use of the River Thames for transport and logistics to minimise movements by road, including TBM sections delivered by river and 2.7million tons of TBM spoil removed
• The Legacy Programme will benefit ecology, public health, the environment and the appearance of the Thames through formal commitments on five key themes: environment, health and safety, economy, people, and places
• Innovative implementation of hybrid cutting wheels on the hydromill to increase production and improve efficiency for the integral diaphragm walls

Over 3,000 authorizations achieved seven months ahead of schedule.