West Ruislip Portal Northolt Tunnel update
Work item: HS2-EW-SCS-Ph1-Ar-So-S2 -Tun-3-19/05/25_04
Work Item Summary
- Project Phase
- Phase 1
- Region
- Hillingdon
- Worksite Name
- West Ruislip
- Contractor
- SCS JV
- Type of works
- Tunnelling
- Estimated Start Date
- 26/05/2025
- Estimated End Date
- 28/02/2026
What we are doing
Our tunnel boring machines have completed the twin-bore tunnel between West Ruislip and Green Park Way Ventilation Shaft.
We can now progress with building the walkways inside the tunnel. There will be a wider walkway which will allow passengers to safely evacuate a train and walk to the nearest cross passage and rescue train should there be an emergency. The narrower walkway built on the other side will be for maintenance access in the tunnel.
Lorries will deliver ready-mixed concrete to the electric pumps located behind a two-metre high wall at the tunnel entrance. Concrete will be pumped through a pipe into the concrete mixer truck and taken into the tunnels. The walkways will be built the entire length of the tunnel using a formwork system.
Formwork is a temporary structure which shapes the walkway. Concrete is poured into it until it hardens. The formwork system will be moved along the inside of the tunnel using an onboard generator.
We do not expect the works to be noisy as they will take place inside the tunnel. There will be lorries delivering ready-mixed concrete to the concrete pumps on a 24/7 basis. All lorry movements will be within the permitted amount as agreed with the local authority.
Download information relating to these works
Find out more about
If you have a question about HS2 or our works, please contact our HS2 Helpdesk team on 08081 434 434 or email [email protected]