HS2 machines will make Euston final destination

The cutter head of boring machine Karen at Old Oak Common station

Two tunnel boring machines (TBMs) called Karen and Madeleine will dig the final 4.5 miles (7.3km) of tunnels that will bring the HS2 line into Euston station.

Each weighing 1,250 tonnes, the machines are being assembled at Old Oak Common.

Karen and Madeleine are then expected to take around 18 months to reach the railway’s final destination.

Major HS2 construction work at a site alongside Euston station has been halted since March 2023 due to funding doubts.

Boring machine Madeleine in the tunnel at Old Oak Common station

The machines - which will be 190m (623ft) long when completely assembled - are named after Karen Harrison, the first female train driver in the UK who was based out of Old Oak Common depot and Madeleine Nobbs, the former president of the Women’s Engineering Society.

In the past six months, two launch chambers have been built to facilitate the TBMs.

Disruption due to construction work around the station has been causing frustration among residents and local businesses for close to a decade and will continue for years to come.

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HS2 said final plans for the terminus station at Euston "are still under review" and it is working with government and other stakeholders "to design an affordable station design that can run HS2 services from London to the Midlands".

The completion of the Birmingham to London project was put in doubt in October 2023 when the then-prime minister, Rishi Sunak, said extending the high-speed rail project from Old Oak Common to Euston would be reliant on private investment.

However, in her Budget in October the chancellor Rachel Reeves committed to the funding required to begin tunnelling work to Euston.

When the government announced the new high-speed line to link the capital with regional cities in 2009, it was predicted the London to Birmingham section would be completed by 2020 and cost £7bn.

That phase of HS2 is now expected to open between 2029 and 2033.

The Department for Transport said the remaining project cost is estimated at £45bn to £54bn in 2019 prices, however, HS2 management estimated £49bn to £57bn.