With flight times from Russia to the US lasting over ten hours on average, the introduction of an underwater bullet train connecting both countries could enable travel between the two in as little as 20 minutes.

Plans for this design were first brought forward in 2014, with reports claiming that China was in advanced talks with Russia – who had been discussing the construction of a railway line under the Bering Strait for years. The ambitious plan received a great deal of media coverage at the time with many reporting that it would boost trade links between China, Russia, Canada, and the US.

However, after the initial announcement and excitement, not much more was heard about the project – with no plans being put in place for construction. Recent reports from South China Morning Post have seen the plans being heavily criticised, due to the proposed budget of $200bn.

That being said, there are still indications that China’s underwater rail project may still go ahead. The Chinese Government approved plans for the world’s first underwater bullet train in 2018, with aims to demonstrate that high-speed railways are feasible under the sea.

The planned bullet train project would stretch 77km from Ningbo, a port city south of Shanghai, to the archipelago islands of Zhousan, including a 16.2km underwater section of the line. Although this is considerably smaller than the proposed China–Russia–Canada–US route, if this project is successful it could see China moving forwards with its larger goal.

However, since the announcement of this project in 2018, media coverage and further information have ceased being released, so the progress of the project is hard to gauge.

It goes without saying that the construction of this project would be one of the greatest engineering challenges, paired with the sky-high costs. However, arguably most importantly, it could create dynamic political relations between the US, Russia, and China.

Experts have noted that the most challenging element of the project would be constructing the crossover at the Bering Strait, due to this section containing the longest underwater tunnel in the world – extending for over 103km. This construction would be expected to take between 12-15 years, at an estimated cost of $35bn just for the underwater link.

To connect the land to the sea, new infrastructure will need to be laid out due to the closest terminus being located 3,000km away in Russia, while in Alaska the project would require over 1,200km of new railway line. To develop the missing infrastructure to connect the project, it has been estimated that over $200bn would be needed, which according to critics is out of proportion.

Willis Rooney, an economist at GlobaData, comments on the economic feasibility of the project: “I can’t see much evidence of intention to develop this project from any official sources, only an announcement by someone at the Chinese Academy of Engineering, who may have now passed away. It seems like it could be more a pipedream than an actual project.”

“If it was to proceed – though I believe that would be incredibly unlikely – project costs would be a significant hindrance to its feasibility, particularly given the growing public debt levels at Chinese state-owned enterprises, which are likely to discourage investment in more fanciful projects such as this.

“Geopolitical tensions are another likely stumbling block. These ambitious multinational projects tend to struggle to get off the ground, with differing national priorities and demands hampering the progress of development.”

As impressive as it sounds, the project appears to be on hold for now with critics continuing to slam the proposal for being ‘economically redundant’, saying that flying and cargo ships are cheaper and more efficient options for trade due to the proposed project being too complex.

However, as technology advances and infrastructure develops, the China–Russia–Canada–US line may just one day be more than a pipe dream.

The HydroFLEX team talks about the train’s development and testing.