Project Description

Tunnelling began on the Lane Cove Tunnel on 24 June 2004 and the tunnel opened for traffic on March 25th 2007. The completion of the 110-kilometre Sydney orbital network includes the 3.6km Lane Cove Tunnel and the widening of the Gore Hill Freeway. The Lane Cove Tunnel consists of twin, 3.6 kilometre, two-lane tunnels, with three lanes provided in long sections to improve safety and traffic flow for tunnel users.

The eastbound tunnel begins as two lanes, with a third lane from about 1.1km into the tunnel. This lane leads to the exit on to the Pacific Highway and a new transit lane on the Gore Hill Freeway.
The westbound tunnel is three lanes for almost its entire length, with two lanes from the beginning of the tunnel on the Gore Hill Freeway with a continuous third lane from the connection of the Pacific Highway entry ramp traffic with the main tunnel. The first breakthrough in one of the two tunnels being constructed beneath Epping Road occurred in May 2005 after 11 months of excavation.

A roof failure occurred during excavation of an exit ramp in November 2005. Factors blamed for the collapse included the presence and alignment of a low-strength dolerite dyke, orthogonal jointing associated with the dyke, and the presence of faults, which – in conjunction with the dyke and the jointing – created unstable ground.The collapse opened a hole about 10m wide by 10m deep, which threatened to undermine the foundations of a nearby three-storey unit block on the Pacific Highway exit from Epping Road. No-one was injured in the collapse and the hole was backfilled with concrete.

The Lane Cove Tunnel has Australia’s most advanced tunnel ventilation system. Other works undertaken in association with the Lane Cove Tunnel include an additional lane in each direction on the Gore Hill Freeway to be provided as transit lanes and two new traffic ramps linking the Warringah Freeway and Falcon Street at North Sydney.
After three years of construction by 9000 workers, the first motorists were escorted through the $1.1 billion tunnel under police escort shortly before 2pm (AEST) 25th March 2007. The construction of the tunnel has created 48 road changes and is expected to attract 80,000 vehicles a day