Huge step forward for London’s 25km super sewer as tunnelling begins

Today marks a milestone moment for the £4.2bn Thames Tideway project as the first of six tunnel boring machines (TBM) was switched on and lay the first ring on the 25km “super sewer”.

The work has started within Tideway’s central section in Kirtling Street, Battersea, ahead of a 12km excavation drive. The first of the TBMs to move forward is Millicent, named after Dame Millicent Fawcett, an English suffragist, and will tunnel 5km from Kirtling Street to Carnwath Road in Fulham.

Ursula, named after Audrey ‘Ursula’ Smith, a British cryobiologist at King’s College Hospital, will eventually tunnel the other 7km from Kirtling Street to Chambers Wharf in Bermondsey. The project is being split into three distinct sections, with three main ‘drive sites’ – from which four TBMs will be launched to construct the main tunnel.

The TBMs in the central section measure more than 100m long when fully assembled and weigh in at 1300 tonnes with the first shipment of their parts made at the start of February from the across the Channel after being built in Le Creusot, France.

It’s a welcome step forward for those behind the largest infrastructure project ever undertaken by the UK water industry as the tunnelling process was originally due to commence at the back end of summer. The TBMs are expected to remain underground for almost two years as they dig the tunnels.

The scheme is being constructed to tackle the problem of sewage pollution in the River Thames with the promise of “reconnecting Londoners” by preventing millions of tonnes of untreated sewage flowing into the Thames each year.

Commenting on the start of tunnelling, Mark Sneesby, chief operating officer for Tideway, said: “Laying the first ring on the Thames Tideway Tunnel is a huge milestone that we’ve been working towards for more than a year. While you might have spotted our sites above ground along the River Thames, our team underground are now also in full swing as they start digging the 25km super sewer that will help clean up our river.

Across the development, Tideway will employ up to 4,000 employees across 24 sites of various sizes, stretching from Acton in the west to Abbey Wood in the east. The Kirtling Street is in the central section of the Tideway project which is being delivered by the Ferrovial Agroman UK and Laing O’Rourke joint venture.

Juan Martinez, tunnelling project manager at the Kirtling Street site, added: “Today is a momentous occasion for us as we switch on the first TBM on the Thames Tideway Tunnel, taking us one step closer in our mission to clean up the River Thames. Such a large-scale project like the Thames Tideway Tunnel requires a huge range of skills, and it’s great to see Tideway working towards developing the next generation of tunnellers to ensure we can continue delivering vital infrastructure in the future.”

As the first of the TBMs begin work, Tideway has also announced that 12 new apprenticeships are being offered a first of its kind opportunity to train as the next generation of tunnellers. The Level 2 tunnelling apprenticeship was approved in January 2018, and this is the first time it has been offered in the industry, offering trainees a chance to learn tunnelling skills while studying at the same time.

Scott Young, Tideway’s head of Skills and Employment, said: “This is the first opportunity to deliver a full cohort of tunnelling apprentices since the standard was approved in January. For our contractors and their wider supply chain to commit to employing these individuals and embedding them within their tunnelling gangs marks a major step forward for Tideway and we hope it will lead the way in delivering similar apprenticeships on major programmes in the future.”

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