Bohai Strait Tunnel Connects Dalian Yantai 123km Rail Link

[BEIJING] – Chinese authorities are evaluating a proposal to construct a 123–125 km rail tunnel under the Bohai Strait to connect the port cities of Dalian and Yantai. The project, with an estimated cost of 200–300 billion yuan (€25–€35 billion), would reduce travel time from 6-8 hours to approximately 40 minutes. A firm timeline for approval has not been announced, though 2035 has been cited as a potential completion target.

What Is the Full Scope of This Project?

The proposed link is designed as a dual-purpose corridor for both high-speed passenger trains and rail freight, aiming to integrate the industrial hubs of Liaoning and Shandong provinces. The plan specifies a total length of 123–125 km, with an unprecedented underwater section of approximately 90 km. The design accommodates train speeds of up to 250 km/h and involves a twin-bore tunnel structure with a central service gallery for maintenance and emergency evacuation, a standard for major subsea tunnels. The project’s primary obstacles are its immense cost and significant engineering challenges, including complex geology, seismic risks, and high water pressure across the strait.

Key Project Data

How Does This Compare to Similar Projects?

If completed as proposed, the Bohai Strait tunnel would become the world’s longest underwater railway tunnel by a significant margin. Its planned 90 km subsea section is more than double the 37.9 km underwater portion of the Channel Tunnel connecting the UK and France. The world’s second-longest, Japan’s Seikan Tunnel, has a 23.3 km segment under the Tsugaru Strait. The cost estimate of up to €35 billion also places it among the most expensive transport infrastructure projects globally. For reference, the recent estimate for the much shorter Key Bridge rebuild in Baltimore, Maryland is $9 billion, or approximately €8.4 billion (Source: CBS News, 2024).

Editor’s Analysis

The Bohai Strait tunnel proposal is a clear indicator of China’s strategy to overcome geographical barriers for economic integration and supply chain efficiency. While the passenger time savings are significant, the project’s freight capacity is critical in the context of China’s growing logistics demand. The national rail freight market is projected to grow by 4-6% in volume annually through 2035, driven by government incentives for rail transport (Source: AutomotiveWorld, 2026 Edition). This tunnel would function as a major artery to support that growth between the country’s northeastern and eastern economic zones, though its high cost remains a major hurdle to a final green light.

FAQ

Q: Why is the Bohai Strait tunnel being proposed?
A: The primary goal is to create a direct link between Dalian and Yantai, reducing the current 6-8 hour journey around the Bohai Sea to a 40-minute train ride. This would significantly strengthen economic ties between the Liaoning and Shandong provinces.

Q: Has construction on the Bohai tunnel started?
A: No, the project is still in the consideration and planning stages. No final approval has been granted, and a financing model has not been publicly confirmed.

Q: What makes this tunnel different from others like the Channel Tunnel?
A: The main difference is scale. The Bohai tunnel’s proposed 90 km underwater segment is over twice as long as the 37.9 km subsea section of the Channel Tunnel, making it a far more complex and costly engineering challenge.