It was built as part of the Thames Tideway Scheme and runs from Abbey Mills Pumping Station down to pumps and storage tanks at Jenkins Lane, Beckton Sewage Treatment Works.
Lying at −75 metres (−246 ft) AOD means a second source of London's old-style combined sewers' effluent can be caught, that from the Thames Tideway Tunnel, which is due to open in 2025.
The contract price, combined with Thames Water's own improvements was estimated at £635 million.
In February 2012, the TBM, built by Herrenknecht and named Busy Lizzie, started work at the east end.
[4][5] The tunnel was completed, and opened by Mayor of London Boris Johnson, in January 2016.