The Tuen Mun to Chek Lap Kok Subsea Tunnel

This massive project will link the Hong Kong Airport to the mainland via 4.7km of twin road tunnel.

The first 500m of the northern approach tunnel is 17.6m in diameter and was constructed using a Herrenknecht mix shield TBM which is the largest diameter TBM built to date.

The rest of the twin tunnels will be constructed using twin 14m diameter Herrenknecht mix shield TBMs.

The maximum depth of the tunnels is expected to be 60m and this will require the use of Trimix breathing gas and saturation diving techniques where an eight man crew will live under pressure in a habitat for 28 days at a time and be transported to the TBM by a pressurised shuttle for each work shift.

This is the first time these techniques have been used in Hong Kong or Australia..

The project is a Dragages – Bouygues Joint Venture.