China Advances High-Speed Rail With Yangtze River Tunnel Breakthrough

China, August 2026 – China has achieved a major construction milestone on the Chongtai Yangtze River Tunnel, a critical component of the Shanghai-Chongqing-Chengdu High-Speed Railway. The project will connect Shanghai’s Chongming Island with Taicang in Jiangsu province and introduce high-speed rail connectivity to the island for the first time.

The tunnel-boring machine, named “Linghang”, completed an 11.3-kilometre underwater section in a single operation, setting a record for the longest distance bored by a 15-metre-diameter machine of its type. The tunnel is located approximately 89 metres below the river and is being engineered to accommodate trains operating at speeds of up to 350 km/h.

The project demonstrates the increasingly demanding engineering requirements associated with high-speed underwater rail infrastructure. Maintaining millimetre-level alignment accuracy is particularly important at 350 km/h, while the tunnel must also withstand significant water pressure and potential ground settlement. The completed crossing is expected to take around two minutes for high-speed trains.

The Chongtai Yangtze River Tunnel carries an estimated investment of more than 7.1 billion yuan (US$1.05 billion) and forms part of the wider Shanghai-Chongqing-Chengdu High-Speed Railway. The approximately 2,000-kilometre corridor is expected to connect major metropolitan regions across eastern and inland China, with the wider railway estimated to require more than 530 billion yuan in investment.

The breakthrough highlights China's continued development of specialised tunnelling capabilities for high-speed rail and complex geographic conditions. As railway networks expand across rivers, dense urban areas and challenging terrain, advances in large-scale tunnel boring and precision construction are becoming increasingly important to the delivery of high-capacity rail corridors.

Source: The Star