Client DC Water will be hoping that the latest tunnel boring machine (TBM) launched on a water project in Washington DC, US doesn’t live her to her full name – Lucy Diggs Slowe, or Lucy for short, after Howard University’s first dean of women.
Lucy is the third TBM to be launched on DC Water’s Clean Rivers Project, which involves construction of 21km of tunnels to prevent combined sewer overflow (CSO) into rivers in Washington DC.
Contracting joint venture Skanska-Jay Dee will use earth pressure balance TBM Lucy, along with ground freezing techniques, to drive the $157M (£105M) First Street Tunnel (FST) part of the project.
During a storm event, the 7m diameter FST will store up to 30M litres of combined sewer overflow in its 855m long tunnel and four shafts to prevent discharge into the Pontomac River.
The Herrenknecht TBM was first used on a water project in Abu Dhabi and the manufacturer has undertaken a major refurbishment before it was delivered to the FST project.
The other TBMs working on the project are Lady Bird on the Blue Plains Tunnel and Nannie on the Anacostia River Tunnel. Lady Bird is named after environmentalist and former first lady Claudia Alta Taylor Johnson, while Nannie is named after prominent African-American educator Nannie Helen Burroughs.
The TBMs will be keeping twitter followers up to date with their progress as each has its own twitter account. Follow them at @LucyTBM, @LadyBirdTBM and @NannieTBM