Pit bottom to pit stop; tunnel boring machine Ursula arrives at Blackfriars

Ursula, one the tunnel boring machines (TBMs) being used to dig the central section of London's new super sewer has reached Blackfriars Bridge where she will undergo scheduled maintenance ahead of her final drive.

The giant machine recently completed half of her stretch of the main tunnel when passing Waterloo Bridge. Upon arrival beneath the site at Blackfriars Bridge Foreshore, Ursula will undergo a pit stop for several weeks to prepare for the final part of her journey to Chambers Wharf in Bermondsey.  

In March 2019, Ursula became the second giant tunnelling machine to be launched from a 45m deep shaft at Tideway's Kirtling Street site in Battersea. Since then, the TBM has covered over 4 kilometres, following a subterranean route below the River Thames. Her journey so far has seen her pass by famous landmarks including the London Eye and the Houses of Parliament. 

The TBM, one of six to be used on the project, has also journeyed beyond Tideway sites at Heathwall Pumping Station, Albert Embankment and Victoria Embankment.

Ursula is named after Dr Audrey 'Ursula' Smith, a British cryobiologist who discovered the use of glycerol to protect human red blood cells during freezing. To date, the machine has installed over 2,300 concrete segment rings which are used as the primary lining for the tunnel. Each ring is made up of eight segments including a key stone, and weigh in excess of 30 tonnes.

So far, over three million tonnes of excavated material has been removed from sites on the Tideway project and transported by barge on the river preventing the need for thousands of lorry journeys on London’s roads.

Millicent, the westbound TBM launched from Kirtling Street, completed her 5km journey to Tideway's Carnwath Road site in Fulham late last year, becoming the first tunnelling machine on the project to complete her section of the main tunnel.