HS2 halts London tunnel construction after serious site safety incident

Construction across the London tunnels section of the HS2 project has been temporarily suspended after a serious safety incident on September 29 at the Green Park Way ventilation shaft in west London. Two workers inside a mobile elevating work platform narrowly avoided injury when a steel beam, being removed as part of gantry crane de-rigging, rotated unexpectedly and struck their basket.

According to initial findings, beam clamps reportedly slid along the main beam during the lifting process, causing the structure to swing and impact the elevated platform. The workers, who were secured with harnesses, escaped serious injury, though the platform sustained significant damage. HS2 confirmed that all work, apart from essential maintenance, has been brought to a safe stop pending a full investigation and safety review.

The construction pause affects all operations. HS2 Chief Executive Mark Wild stated that a full review of site procedures and leadership practices is underway before work resumes.

While no one was harmed, HS2 described the incident as posing a “serious risk” to personnel. The investigation aims to assess whether existing lifting and de-rigging protocols meet current safety standards for complex underground construction environments.

The suspension occurs amid a broader “comprehensive reset” of HS2 led by Mark Wild, who was appointed to stabilize costs and address scheduling challenges. With tunneling machinery dismantlement ongoing, the halt could contribute to further delays in London operations. The HS2 project remains under national scrutiny due to its escalating cost projections, now estimated to exceed £100 billion, and a revised completion window extending between 2036 and 2039. The priority, officials emphasize, remains ensuring that all future works resume only after confirming full compliance with safety protocols.