A key milestone has been reached at Tideway’s Chambers Wharf site in Bermondsey with the completion of diaphragm walling, in preparation for digging the tunnel shaft.
Chambers Wharf is one of a number of sites across London that will be used for the construction of the Thames Tideway Tunnel, the 25km super sewer being constructed to tackle the problem of sewage pollution in the River Thames.
Jim Avant, Delivery Manager for Tideway, says, “After several months of hard work the completion of the diaphragm wall works at Chambers Wharf marks a significant milestone for the project and means we can now get on with digging our tunnel shaft.
“It was no mean feat, around 35,000 tonnes of material excavated during the works, all of which was removed from site by barge in line with Tideway’s commitment to remove as much material as possible by river. Similarly, all reinforcement cages for the walls have been delivered to site by barge.”
A diaphragm wall is a concrete structure inserted in the ground and used to keep an excavation open, an essential part of digging a tunnel shaft.
The diaphragm walls at Chambers Wharf are 1.5 metres thick and are constructed to a depth of just over 72 metres.
The works were completed using an innovative electrically powered hydrofraise, developed specifically for use at Chambers Wharf.
Works at Chambers Wharf will now move onto the next phase with a busy period through the summer as work begins on archaeological works in the shaft and construction of an acoustic enclosure, which will enable main tunnelling works to be completed inside to prevent noise disruption to local residents and businesses.
Tunnelling on the Tideway project will begin later this year.
Chambers Wharf is part of the East section of the project which is being constructed by a joint venture between Costain, Vinci Construction Grands Projets and Bachy Soletanche.