The Thames Tideway Tunnel is Europe’s largest water infrastructure project, creating a 16km-long, deep-level ‘Super Sewer’ to reduce sewage overflow into the River Thames. Several shafts were needed to launch tunnelling equipment or to channel sewage flows into the main sewer, including some shafts that were built over the river.

Beckett Rankine was commissioned to design platforms that would create a safe working environment while a number of these river shafts were constructed.

At the Victoria Embankment foreshore, we produced the design and specifications for a temporary sheet-piled cofferdam that would also allow the construction materials to be delivered by river.

It was expected that excavations would reach below the mean water levels, and so the twin walls were sealed to the existing river wall to limit the ingress of water into the enclosed working area. We also undertook a detailed three-dimensional non-linear analysis to assess the structure’s vessel impact absorption capacity.