The 25km Thames Tideway Tunnel project has been given the go-ahead. The £4.2b scheme will modernise London’s Victorian sewerage system and tackle sewage discharges into the Thames.
Communities Secretary Ed Pickles and Environment Secretary Elizabeth Truss both signed the order granting the building and operating of the scheme.
Ed Pickles said: “This is a challenging infrastructure project, but it is clear that the Thames Tunnel will help modernise London’s ageing Victorian sewerage system, and make the River Thames cleaner and safer.”
Dubbed London’s “super sewer”, the Thames Tideway Tunnel is a sewer set to run from west to east London, roughly following the route of the River Thames at about 75 metres below ground. The 7.2m diameter tunnel will connect up to 34 of the most polluting sewer overflows identified by the Environment Agency, capturing up to 39m tonnes of sewage which would otherwise spill into the Thames, transferring to Beckton Sewage Treatment Works for treatment which is currently being expanded by 60 per cent to cope with increased volumes.
The tunnel will be created using six boring machines from five drill sites, eventually connecting to the Lee Tunnel which is currently under construction. Work will get underway at 24 sites along the project’s route, from Acton in west London to Abbey Mills in east London. Once underway, the project will create approximately 4,000 jobs.
The work will be divided into three lots: West, Central and East. Contract value for the West lot is worth between £300 - £500m, for the Central lot between £500m - £800m, and for the East lot between £600m - £950m. Bids are currently being prepared for work on the lots with successful bidders announced sometime next summer.
The project will be paid for by Thames Water customers whose bills are expected to rise by £70 - £80 per year within ten years’ time. The Chief executive of Thames Tideway Tunnel, Andy Mitchell, said: “If the tunnel had been in operation last year, it would have captured 97% of the sewage that poured in to London’s river. Hardly a week goes by when untreated sewage is pouring in to London’s river and we are pleased that we can now start to tackle this archaic problem.
“This is a huge project but it’s a huge problem, and we can now get on with tackling it. It’s no easy task, but we’re confident that we can deliver this project and still achieve our aim of minimising the impact on our customer bills.”
Construction on the tunnel is now scheduled to begin in 2016.