Construction of Britain’s new high-speed railway has passed a major milestone with excavation of the 8.4-mile Northolt Tunnel under London. The fourth of four tunnel boring machines (TBMs) being used to dig the twin-bore tunnel – the second-longest on the HS2 route between London and the West Midlands – completed its work on 26 June.
The machine, named Anne, installed the final concrete ring underground before emerging into a vent shaft at Green Park Way in Greenford.
The Northolt Tunnel will take HS2’s new high-speed trains between West Ruislip at the outer edge of the capital and the new Old Oak Common super-hub station in west London.
The Northolt Tunnel, which is 35 metres below ground at its deepest point, has been bored by our Skanska Costain STRABAG JV (SCS JV) team using four TBMs. Two built the 5-mile western section from West Ruislip and two built the 3.4-mile eastern section from Victoria Road in North Acton.
All four machines finished their journey at Green Park Way where they are to be lifted out from the underground shaft. The third TBM, Emily, finished its tunnel bore earlier this month, and will be lifted out of the ground later this summer. The first two machines to arrive, from West Ruislip, were lifted out earlier this year.
Alan Morris, Construction Delivery Director, HS2 Ltd, said: “Completing the excavation of this 8.4 mile-long tunnel on HS2 is a real achievement and one the team should be immensely proud of.
“We’re building HS2 for the future, to increase capacity on our rail network and improve journeys for millions of rail users. The construction of HS2 is already bringing benefits, with £20bn economic benefit already being delivered at either end of the line.”
