Tunnel Boring Machine (TBM) Annie has reached our Earl Pumping Station site in Deptford. This marks the 2.2km point of an overall 4.5km journey from Greenwich Pumping Station to Chambers Wharf in Bermondsey.
TBM Annie is constructing the Greenwich Connection Tunnel which will connect into the existing sewer network and will transfer sewage into the main super sewer at Chambers Wharf. Our work at Earl Pumping Station will reduce annual sewer discharges into the River Thames locally.
Ahead of Annie’s arrival, the shaft needed to be fully excavated and a base slab installed. It was then partially backfilled with a temporary cement material into which the TBM could tunnel. Above this, the shaft was filled with water to match the external water pressure of five bar. This special ‘plunge pool’ balances the ground pressure allowing the team to tunnel straight into the shaft.
While TBM Annie is at Earl Pumping Station, a cutterhead inspection will take place any cutting teeth replaced if necessary.
Brooke Knight, project manager at Earl Pumping Station, said: “After months of preparation it is exciting to welcome Annie into our site. Earl Pumping Station is a small and confined site and the team have worked hard to ensure we were ready for her arrival.”
TBM Annie is named after Annie Scott Dill Russell, the first female scientist to work at the Greenwich Observatory.
Earl Pumping Station is part of an existing Thames Water Pumping Station and remains operational throughout our works.