Central Tunnel of Central Kowloon Route

The Central Kowloon Route project, also known as Route 6, involves the creation of an east-west underground road link on the Kowloon Peninsula, between Yau Ma Tei and Ma Tau Kok.

With a total length of 4.7 kilometres, the infrastructure includes a 3.9-kilometre main tunnel, 2.8 kilometres of which will be built by Bouygues Travaux Publics and Dragages Hong Kong, with 2×3 lanes.

The contract includes the construction of two access tunnels and the excavation of a pilot tunnel approximately 1.5 kilometres long, with a minimum internal diameter of 5 metres, using a tunnel boring machine between the vertical access shafts at Ho Man Tin and Ma Tau Kok. Sections of open-cut tunnels approximately 41 metres and 33 metres long complete the project, along with the foundations for a ventilation building, a ventilation shaft, an access gallery at Ho Man Tin and the construction of 30 branches.

This new underground route aims to improve traffic flow and reduce surface congestion in one of Hong Kong's most densely populated areas.

The tunnel was built in a complex urban and geological environment, with a route crossing seven geological faults, including three major ones, and thin rock cover.

The work was carried out in close proximity to four underground lines, several major roads, a hospital and sensitive facilities. Excavation methods were adapted to limit vibrations and settlement, combining mechanical excavation with grouting for reinforcement, etc.

The project incorporates high safety and impact control requirements, contributing to a sustainable improvement in mobility conditions and the living environment above ground.