The project to construct a new gas pipeline underneath the river Humber has hit a major milestone as the tunnel boring machine (TBM) passes the halfway mark on its 5km journey.
The new 3.5m diameter tunnel currently under construction will house a vital replacement gas pipeline which will carry around 20% of the gas Britain needs, supplying homes and business across the east of England.
The 510 tonne TBM, named Mary after Mary Fergusson, the first female fellow of the Institution of Civil Engineers, reached the halfway point on her journey from Goxhill to Paull at 2.30am on Tuesday 8 January.
Over 12,000 concrete segments have already been fitted into place during 200,000 hours of work, with more to come.
National Grid project manager Steve Ellison said engineers on the project had done a “brilliant job under challenging circumstances”.
“Mary has done a brilliant job to date and we and our contractors are delighted to have reached the halfway point on the tunnel,” he said.
“There is still a lot more work to do but I would like to say a big thank you to the 40-strong team of engineers who have worked around the clock in very challenging conditions to get us to this important milestone.
“The machine has pretty much been operating 24 hours a day with the odd shut-down for repair or maintenance since the tunnelling work started on 6 April 2018. There are 20 engineers manning her on every shift and they work in very cramped and warm conditions, far below the river bed.”
Mary was specially built for this project in Germany and her name was chosen by Kasey Doney, aged 8, a pupil at Paull Primary School near Hull.
Once the tunnel is finished, and Mary is removed from the tunnel via a shaft on the opposite bank of the river at Paull, the work on the next phase of the project will begin which will involve the installation of the gas pipeline.
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