China is considering a massive tunnelling project

The Chinese authorities have announced plans to construct the world’s longest undersea tunnel. Measuring a colossal 123km long, the tunnel route runs under the Bohai Sea and is intended to connect Dalian in Liaoning Province with Yantai in Shandong Province. The tunnel was first proposed in the mid-1990s when it was expected to cost in the region of US$10.3 billion to build but the project was shelved due to the enormous construction challenges it posed. However tunnelling technology has moved on and the Chinese authorities now believe the project is viable, although it is likely to cost $42.5 billion to construct. If the work goes ahead as planned, the tunnel is expected to take six years to construct and will then become part of China’s high speed rail network. The Chinese Academy of Engineering is working on the design for the tunnel at present and has said that the project cost could be recouped in as little as 12 years as the link would replace a lengthy overland journey. The world’s longest undersea tunnel at present is the 53.5km Seikan link in Japan, while the Channel Tunnel connecting the UK and France measures 50km.