One down, one to go
As work gets underway on the second of the twin bores at Long Itchington Tunnel, the transport secretary makes a historic journey through the one already completed.
TRANSPORT Secretary Mark Harper and HS2 chief executive Mark Thurston made a historic journey on December 1, driving from end-to-end through the completed bore of the milelong tunnel at Long Itchington in Warwickshire.
“It was absolutely extraordinary to see firsthand the sheer scale and craftsmanship of this monumental project which will positively transform the lives of hundreds of thousands of people across the North and Midlands,” commented Mr Harper.
“As well as boosting connections, regenerating communities and creating tens of thousands of jobs, tunnels such as this have been designed to ensure Britain’s biodiversity and countryside are preserved during construction and for many decades to come.”
The tunnel, 33 metres (108 feet) below ground, was constructed in order for the route to avoid cutting through ancient woodland above. It was created by 2000 tonne, 125-metre (410 feet)-long tunnel boring machine (TBM) Dorothy, which was launched at the north portal on December 2, 2021.
Named after Dorothy Hodgkin, the first British woman to win the Nobel
Prize in Chemistry, the TBM broke through at the tunnel’s southern end in July 2022. Its 10-metre diameter cutting head, tail skin and eight other large pieces from its front and middle shield were removed and returned to the site of the north portal by road in preparation for starting work on the second bore. The gantries, which weigh in excess of 1000 tonnes, were brought back through the tunnel.
Secord bore
Reassembled in a three-month operation, Dorothy’s second one-mile drive got underway in late November. It is expected to break though in the summer.
Long Itchington will be the first twin tunnel of the HS2 project to be completed. The excavation of the bores involves the removal of around 500,000 tonnes of mudstone and soil, which is being processed on-site and separated before being moved by a 254-metre (278 yard) conveyor for use in building embankments for the route of the railway.