A milestone has been reached with the completion of constructing the foundations for the new HS2 station at Old Oak Common station in West London.

The station will have six platforms for high-speed trains.

Construction of the base for the 850-metre-long underground station began in April 2023 and required 76,000 cubic metres of concrete and 17,000 tonnes of reinforced steel.

At its deepest point, the base is nearly two metres thick and covers 45,000 square metres, equivalent to more than six football pitches.

Excavation of the box required the removal of 1.3 million tonnes of London clay and was completed in the summer of 2024.

The base slab was created by installing blinding, layers of shingle for drainage, laying a matt on top, followed by installing a 1.85-metre-high reinforcement layer and pouring concrete to complete the slab.

The concrete came from a dedicated batching plant on site, and over 90% of the concrete used for the base slab was manufactured on site, reducing lorry movements and CO2 emissions. Low carbon ECOPact concrete was also used to reduce the amount of carbon used during construction.

Work is now continuing with the construction of the six HS2 platforms. Wall frameworks are being installed ready for concrete pouring, and the platform slabs are being manufactured ready for installation will begin this spring.

Tunnelling is also taking place to connect the station to the HS2 network, and in the eastern section of the box preparations are underway to launch two giant tunnelling machines towards Euston.

In the western side of the box, the tunnel is being constructed using a sprayed concrete lining method.

When complete, the six underground platforms will connect HS2 with central London in one direction and the West Midlands in the other.

Eight surface-level platforms currently under construction will provide an interchange with Great Western Railway services to the west of England and South Wales, the Elizabeth Line, and Heathrow Express.

“Completing the base slab of the underground station box is a key milestone in building HS2’s new super hub station in West London. This is the final stage in completing the foundations for the high-speed station, and will be where HS2 tracks are laid, platforms are constructed and the station building and roof and built above. At Old Oak Common we are making significant progress in building this state of the art, environmentally friendly, transport hub which will be a key part of the HS2 route.”

Peter Gow, HS2’s Project Client for Old Oak Common