Preparations accelerate on London’s super sewer as tunnel-boring machines arrive

Tunnel-boring machines (TBMs) that when fully assembled will weigh more than 1300 tonnes each and measure more than 100m long have arrived in London after sailing down the Thames today.

The first shipment of the TBMs, named Millicent and Ursula, have made the 500-mile journey from the across the Channel after being built in Le Creusot, France. They arrive as Tideway, the company building London’s super sewer, prepare to begin tunnelling later this year.

The Thames Tideway Tunnel is a 25km super sewer tunnel being constructed to tackle the problem of sewage pollution in the River Thames. Once completed it will stop millions of tonnes of untreated sewage flowing into the Thames each year.

To make the journey from France, the machines had to be dismantled and will arrive in several parts over the coming weeks and be reassembled at Tideway’s Kirtling Street site in Battersea, close to Battersea Power Station.

Andy Mitchell, Tideway’s chief executive officer, has hailed today as another “exciting milestone” in the major project’s timeline which is of great importance to the future of London.

“This is going to be a big year for Tideway and we’re working hard to get tunnel shafts completed in preparation for the start of tunnelling later this year,” Mitchell added. The arrival of Tideway’s second and third TBMs is another exciting milestone, signalling that work is gearing up on London’s super sewer. It is particularly fitting that we are delivering Millicent during the centenary of the right to vote for women in 1918.”

Teams have named Millicent after Dame Millicent Fawcett, an English suffragist, intellectual, and political leader, who is soon to be the first woman to be commemorated with a statue erected at Parliament Square.  Similarly, Ursula was named after Audrey ‘Ursula’ Smith, a British cryobiologist at King’s College Hospital in South London who discovered the use of glycerol to protect human red blood cells during freezing.

The TBMs were transported along the Thames in order to keep in line with Tideway’s commitment to transport over 90% of materials by river which will reduce the number of road vehicle journeys needed to build the tunnel. Millicent will tunnel 5km from Kirtling Street to Carnwath Road in Fulham while Ursula will tunnel 7.6km from Kirtling Street to Chambers Wharf in Bermondsey.

Some key milestones have been achieved on the major project in the last few months as preparations move closer to the beginning of tunnelling. The first tunnel shaft at Kirtling Street has been recently completed near the Battersea Power Station. At 60m deep, the crews dug through several layers, excavating 45,000m3 of spoil – enough to fill 18 Olympic-sized swimming pools. 

The video at the top of the page shows the progress made by some of the 4,000 workers who are pressing ahead with the project. 

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