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Tunnelling works in Hillingdon

We will be building approximately 30 miles of tunnel beneath London, stretching from West Ruislip in the west through to the Euston approaches in the east. HS2 tunnels are referred to as twin bore tunnels, because there are two tunnels that will run parallel to each other – one carrying trains travelling from the West Midlands to London (known as the southbound or London tunnel), and one that will carry trains travelling from London to the West Midlands (known as the northbound or Birmingham tunnel).

The Northolt Tunnels will carry passengers from Old Oak Common station 8.4 miles under London to West Ruislip.  These will be constructed using four tunnel boring machines (TBMs), in two phases known as Northolt Tunnels West and Northolt Tunnels East.

To build the Northolt Tunnels West, two TBMs will be launched at the West Ruislip Tunnel Portal, which is adjacent to the Ruislip Golf Course, and will travel five miles each to the Greenpark Way ventilation shaft, located roughly adjacent to the south of the Horsenden recreation ground.  The first TBM is scheduled to be delivered to the West Ruislip Portal at the end of 2021, and will be launched in summer 2022.  The second machine will be launched soon afterwards.

The West Ruislip Portal will be our tunnel logistics site for the Northolt Tunnels West.  We will keep you informed about our above ground proposals for the tunnelling logistics as the scheme develops.

In September 2021 we held two online public events about tunnelling in Hillingdon. The presentation we gave at those events included information about the tunnel locations, how and when the tunnels will be dug and how we will manage the impacts of tunnelling.

Watch a recording of the presentation.

View or download our Tunnelling in Hillingdon presentation, September 2021