The Thames Tideway Project is the planned upgrade of London's sewerage system to cope with the demands of the city well into the 22nd Century. The new Thames Tideway, 25 kilometre interception, storage and transfer tunnel will run up to 65 metres below the river to Beckton. Beckton STW, one of Europe's largest sewage treatment works, is being upgraded as part of the scheme with the addition of a new outfall from which the processed water from the Lee Tunnel will then be discharged into the Thames.
Scope of Works
Where the Lee Tunnel runs into Beckton STW, the treated water is discharged through a twin pipe outfall into the River Thames. Buried in the tidal zone of the river with heavy flows, the twin pipes would have to be protected with the rock armour around the outfall culvert and a scour matress to prevent siltation of pipes and erosion of material.
WM Plant Hire selected their 100 tonne long reach excavator working from a pontoon at the end of the tunnel outfall in the River Thames. GPS underwater dig profile equipment was installed to control the rock placement line and level whilst positioned on a floating barge. The 26m reach and heavy lifting capabilities ensured the accurate placement of the rocks underwater. Our marine experienced operator ensured that despite challenging tidal conditions the strict programme was achieved.