China Railway Corporation has given the green light for a 16.2-kilometer undersea high-speed railway tunnel that will allow bullet trains to race at up to 300km/h between the eastern port city of Ningbo and its neighboring island of Zhoushan.

Approved after a feasibility study, the tunnel is part of a 71km rail line that will reduce travel time to just 25 minutes when it opens in 2022. The price tag for the entire project is estimated at 25.2 billion yuan (US$3.63 billion), according to the Xinhua news agency.

The two cities in the eastern province of Zhejiang are at the center of a major industrial hub. Ningbo is a bourgeoning trading center while Zhoushan is home to a Boeing 737 jet assembly plant and has been designated as a pilot free-trade zone. Together the Ningbo-Zhoushan port is the world’s largest in terms of annual cargo throughput.

Screenshot 2018-11-26 at 6.11.42 PM
Ningbo and Zhoushan in eastern China are separated by a narrow stretch of waterway. The two cities are already connected to each other by an expressway formed by a number of sea-crossing bridges. Photo: Google Maps
LOCAL201802020827000145825692840
A passenger takes a picture of her son at Ningbo railway station. Photo: People’s Daily

Local authorities say the tunnel is essential to avoid the new express rail artery hampering the narrow stretch of waterway serving the busy port.

The proposed tunnel is much shorter than the 50km Channel Tunnel between France and the United Kingdom, but it will be constructed in a region prone to super typhoons and will be underneath legions of container berths, thus creating big challenges for engineers. Also, bullet trains will travel at 250km/h inside the future tunnel, while the Eurostar passenger trains shuttling between Paris and London normally slow down to 160km/h while they are in the Channel Tunnel.

Some experts believe the experience gained in the project will help Beijing prepare for a much more ambitious tunnel that would extend the mainland’s sprawling rail network to Taiwan. Plans for a tunnel spanning the 130km Taiwan Strait are being floated, though the current animosity between the two sides means there is no timetable.

China had a rail network spanning 25,000 kilometers at the end of last year that was capable of handling commercial services at a speed of at least 250km/h – equivalent to 60% of the world’s high-speed track.

Read more: Pomp and ceremony as world’s longest sea-crossing opens

Beijing still wants a tunnel to Taiwan, despite political reality

High-riding bonanza on China’s ever-growing metro lines

Glitches mar first day of HK’s express rail link to China