Work Item Summary
- Project Phase
- Phase 1
- Region
- Hillingdon
- Location
- Northolt
- Worksite Name
- Northolt Tunnel East
- Contractor
- SCS JV
- Type of works
- Construction, Tunnelling
- Estimated Start Date
- 19/08/2025
- Estimated End Date
- 30/09/2026
What we are doing
The Northolt Tunnel is 8.4 miles (13.5km) long between Old Oak Common station and West Ruislip, where the HS2 route surfaces.
Our four Tunnel Boring Machines (TBMs) have completed their tunnelling journeys at Green Park Way vent shaft in Greenford. Three out of the four TBMs have been lifted out of the shaft, and the fourth, TBM Anne, will be removed end of August 2025.
We’re also building cross passages (CP), which are short tunnels connecting the two running tunnels to provide a safe evacuation of trains in an emergency. The final cross passage will be completed by the end of September 2025. Please follow this link for details Update: Cross passage construction near Conway Crescent, Perivale – HS2
Works will also continue in Old Oak Common to build the sprayed concrete lining tunnels between Victoria Road Crossover Box and Old Oak Common Station. These works will continue to September 2025, there will then be a pause until summer 2026. Please follow this link for details. Update on Old Oak Common Tunnels – July 2025 – HS2
We are routinely checking boreholes and carry out ground and building monitoring and visual surveys along the tunnelling route. You may notice our surveying team in your local area for short periods. We will let you know if any of our monitoring and visual surveys will impact you directly.
We are now building the walkways inside the twin-bore tunnel. To build the walkways, concrete will be placed in a temporary bridge structure that shapes and supports the concrete until it hardens, to construct emergency and maintenance walkways. These works will be ongoing until February 2026. Please follow this link for details. Update on Northolt Tunnel construction in Hillingdon and Ealing – HS2
Engagement events
Virtual Future Tunnelling Drop In Every third Tuesday of the month, except December – Virtual Drop-ins: HS2 & SCSJV Tunnelling Works
For further details please see notification below.
Download information relating to these works
If you have a question about HS2 or our works, please contact our HS2 Helpdesk team on 08081 434 434 or email [email protected]