Construction starts on mega undersea link

China's longest underwater railway tunnel project begins breaking ground

Tunneling operations began at both ends of China's longest undersea high-speed railway tunnel project on Thursday, according to China Railway's 14th Bureau Group, which is overseeing its construction.

The Jintang Undersea Tunnel, a critical component of the high-speed railway connecting Ningbo and Zhoushan in Zhejiang province, will span 16.18 kilometers upon completion, with a shielded section 11.21 km long, making it one of the world's longest undersea railway tunnels. Trains will travel through it at speeds of up to 250 km per hour.

Construction of the tunnel is one of the world's most ambitious and challenging projects of its kind because of the geological conditions it faces, the immense pressures at depth, and its length, which is nearly 10 km longer than the tunnel on the Hong Kong-Zhuhai-Macao Bridge.