Britain’s largest water engineering project for 20 years, Lee Tunnel, delivered by Morgan Sindall, as part of the MVB joint venture with VINCI Construction Grands Projects and Bachy Soletanche.
The £635m project involved the construction of a four-mile long tunnel to prevent sewage discharges from the largest sewer overflow point at Abbey Mills Pumping Station in Stratford, East London, into the River Lee. The tunnel is seven metres in diameter, equivalent to the width of three London buses, and will stop over 16 million tonnes of sewage, mixed with rainwater, overflowing into the river from the Victorian sewer network when it becomes overloaded. The tunnel will store, then transfer, sewage to Beckton Sewage Treatment Works, expanded to deal with the increased treatment volumes. The first of two planned tunnels, The Lee Tunnel, marks a massive step forward to improve the quality of London’s rivers and is an essential part of providing the capital with a 21st century sewerage system. The project included five shafts, up to 75 metres deep and tunnelling work began in 2012 to meet the required completion date of 2015.