Lee Tunnel

The Lee Tunnel, also known as the East Ham to Stratford deep tunnel, is a tunnel in East London for storage and conveyance of sewage mixed with rainwater. The tunnel is part of the Thames Tideway Scheme and runs from Abbey Mills Pumping Station down to Beckton Sewage Treatment Works under the London Borough of Newham.

This 6.9 km (4.3 mi) long tunnel, of diameter 7.2 m (24 ft), running from 75 m (246 ft) deep at Abbey Mills down to 80 m (260 ft) deep at its terminus at Jenkins Lane, East Ham, will capture 16,000,000 m³ (1.6×10¹⁰ l), or 16 million tonnes, of sewage annually from the single largest polluting CSO in London. This sewage would otherwise flow straight into the River Lea, the Thames Tideway and eventually the Thames Estuary. However, the sewage will now be pumped up to the Beckton Sewage Treatment Works – the largest sewage treatment works in Europe – and the resultant clean water will be emptied into the River Thames. The reason for starting at −75 m is to be ready to collect sewage from the lowest point of the Thames Tideway Tunnel, which is under construction and intended to connect.

Thames Water awarded the construction contract to the MVB JV consortium, comprising Morgan Sindall, VINCI Construction Grands Projets and Bachy Soletanche, in January 2010. The cost was an estimated £635 million.^[1]

The construction of the tunnel began with sinking of vertical shafts in 2010. In February 2012, the TBM, built by Herrenknecht and named Busy Lizzie, started work at the Beckton end. In 2013, a UK record concrete slipform pour was achieved, with 29 days of continual pouring.^[2] The tunnel is the deepest tunnel ever bored in London, exceeding the Crossrail excavations.^[2] The TBM reached Abbey Mills in January 2014.^[3][4] The tunnel was completed, and opened by Mayor of London Boris Johnson, in January 2016.^[5]

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