An overview of subsea tunnel engineering in Hong Kong.

The Hong Kong Cross Harbour tunnel was opened in 1972, breaking the barrier of highway transport between the busiest urban areas of the Kowloon peninsula and Hong Kong Island. With the rapid economic and population growth of Hong Kong between 1970 and 1997, four more subsea tunnels were constructed under Victoria Harbour. The MTR Shatin to Central link will be the sixth such tunnel across Victoria Harbour. Immersed tunnels of different form and structure were adopted for all of these tunnels. To the west of the harbour, two more subsea tunnels are currently being constructed. As a part of the Hong Kong-Zhuhai-Macao Bridge project, the world's longest immersed tunnel is under construction to connect Hong Kong to mainland China. Within the Hong Kong boundary, a subsea tunnel connecting Tuen Mun and Chek Lap Kok will be constructed using a large diameter tunnel boring machine. This paper provides an overview of all the subsea tunnels already built or currently under construction for road and rail transport in Hong Kong. Considerations for selecting the most appropriate method for subsea tunnelling for each location are described. [ABSTRACT FROM AUTHOR]