The 238^th and final barge delivering concrete segment rings used to line the central section of the Thames Tideway Tunnel has arrived at Tideway’s Kirtling Street site.

Each barge transports 30 concrete rings, weighing approximately 30-tonnes each, removing the need for over 14,000 heavy goods vehicle movements on local roads. 

A total of 6,974 concrete rings were required to line the 12.6km Central section of the Thames Tideway Tunnel, excavated by two giant tunnelling machines from Tideway’s Kirtling Street site.

Each ring is made up of seven large segments and a key stone. The segments are safely lowered to the bottom of the shaft, 47m deep below ground, and transported along the tunnel to the tunnel boring machines (TBM) digging London’s new super sewer.

Millicent, the westbound TBM launched from Kirtling Street, completed her 5km subterranean westbound journey to Carnwath Road in Fulham late last year, installing 2,702 concrete rings in this section of tunnel.

The eastbound tunnelling machine, Ursula, recently passed below Tower Bridge some 50m on her 7.6km route to Tideway's Chambers Wharf site in Bermondsey. Ursula has just over 150 concrete rings left to install to complete the primary lining of this stretch of tunnel.  

The GPS Vincia, the vessel delivering the segments to Kirtling Street, has been using a new fuel that offers a 90 per cent reduction in greenhouse emissions. The new fuel, supplied by Green Bio-Fuels Ltd, is an ultra-low emission, sustainable fuel that is generated from a feed stock of solely waste vegetable oil – and does not use palm oil in its production.