Tideway completes final connection tunnel

TBM Annie, named after Annie Scott Dill Russell, the first female scientist to work at the Greenwich Observatory, broke into the shaft at Tideway’s Chambers Wharf site on April 5.

The major milestone means that the only tunnelling work remaining on the super sewer project is the final section of TBM Selina’s drive toward Abbey Mills Pumping Station.

“Although there is much work to be done, it’s great to have reached this milestone – bringing London ever closer to a cleaner Thames,” said tunnel manager Robert Margariti-Smith.

The focus for the tunnelling team will now switch to the removal of the 6.4m diameter TBM from the shaft at Chambers Wharf as well as the secondary concrete lining of the 4.5km tunnel.

TBM Annie, manufactured by Herrenknecht, began her journey at the end of 2020, passing Tideway’s sites at Deptford Church Street and Earl Pumping Station along the drive.

Much of the excavated spoil from the tunnelling operation was removed from site by barge. Tideway invested in new marine infrastructure to use Deptford Creek, near Greenwich, as a transport artery in order to keep lorries off local roads.

A total of six TBMs have been boring the tunnel, the largest of which has a diameter of 8.8m. The so-called “super sewer” is expected to cost around £4.1bn (US$5.47bn) and is scheduled for completion in 2025.