West Ruislip Portal Northolt Tunnel update

What we are doing

Safe stop down to SCS works from 10 October 

 Safety is our number one priority at HS2. Following an incident that occurred at the Green Park Way site in Ealing, works are being safely halted across the London Tunnels section of the route, including sites in Hillingdon. While no workers were physically harmed, our contractor, Skanska Costain STRABAG joint venture, is undertaking a comprehensive review of safety procedures and leadership on their sites before a safe restart can take place. 

Works will be brought to a safe stop and will remain on hold until we’re satisfied that all appropriate measures are in place to protect the workforce. We anticipate the review may take a number of weeks depending on the area and the type of work involved. 

 We will provide details on when the safe stop will be in place over the course of the next week. 

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

• West Ruislip Portal Northolt Tunnel update

If you have a question about HS2 or our works, please contact our HS2 Helpdesk team on 08081 434 434 or email [email protected]