Sarens has expertly lifted the final lid into place for the Thames Tideway Tunnel, London’s new “super sewer” designed to divert vast amounts of storm sewage from the River Thames. When it is fully operational in 2025, the 25 kilometre-long tunnel will almost completely stem the flow of the tens of millions of tonnes of storm sewage that spill into the river each year.

CVBJV (a joint venture between Costain, Vinci Construction Grands Projets and Bachy Soletanche), called Sarens in to install the massive circular shaft cover at the Abbey Mills Pumping Station in Stratford. The 1.200-tonne precast concrete slab was designed to cover the shaft of the massive new sewer, but to install it was going to require Sarens’ custom-built solutions, including a purpose-built gantry system and specialised equipment. 

Sarens had just the right combination of crawler crane, SPMTs, strand jacks, beams, and bracing systems for the job, and deployed our equipment and expert crew to London for the operation. We used: 

• Kamag SPMTs
• Modular beams (MB2500x1000, MB1800x1200, and MB800x900)
• HSL6500 strand jacks
• CC 2800-1 crawler crane
• Bracing systems (BS610 and BS324)

Although the lift itself required five careful hours of coordination and cooperation on-site, the project’s full scope ran from February through April of 2024. Carefully planning every move, Sarens and the client had to figure out how to work around the lack of on-site space for assembling the gantry, the logistics of bringing in 50 truckfuls of equipment from Belgium and Southampton, and the installation of main beams weighing 100 tonnes each. The weight of each component was carefully considered, as were measures to avoid underground services.

It took two months to set up all the necessary equipment, and available space remained a challenge throughout the operation. Sarens used the CC 2800-1 crawler crane to build a gantry for the installation operation, and set eight lifting points where the loads needed to be controlled simultaneously within stringent parameters. 

With everything in place, the crew used eight 650-tonne strand jacks to lift the shaft, and transported it with 64 axle lines of SPMT. A 12-member team was responsible for a successful operation, and Sarens would like to commend them all on a job well done!

Watch the video here!