After years of delays, the Shizuoka section of the ambitious Chuo Shinkansen project, better known in Japanese as the “linear motorcar” and in English as the maglev, which will be able to shuttle passengers from Tokyo to Nagoya in as little as 40 minutes, has finally been given the formal go-ahead by the prefecture, thus prompting JR Tokai, the company in charge of it, to declare that now the real work starts. Given that the project was initiated around the turn of the century and the excavation of the 256 kilometers of tunnels needed to complete the route from Shinagawa in Tokyo to Nagoya has been ongoing for more than ten years, JR Tokai’s declaration requires clarification; but, indeed, in the larger scheme of things the Shizuoka section of the tunnel, though a mere 8.9 km in length, is perhaps more central to the project than any other in that it is probably the most difficult to carry out technically.

According to a series on the maglev in the Asahi Shimbun that commenced July 23, experts have said that building the Shizuoka tunnel section may be the most difficult construction project in the history of Japanese civil engineering. Twenty-five kilometers of the tunnel needed for the maglev—almost 90 percent of the Shinagawa-Nagoya route is underground—runs below the Southern Alps, some of which towers 3,000 meters above sea level. The Shizuoka section is smack dab in the middle of this portion and will be located between 500 and 1,400 meters below the surface. The deepest tunnel in Japan ever excavated is the Oshimizu Tunnel on the Joetsu Shinkansen line, which opened in 1982 and is 1,300 meters deep. But while there is some experience to fall back on, the Shizuoka section still poses some formidable challenges.

Two tunnels have to be built: the primary tunnel that contains the tube for the train, and the “advance” tunnel that delivers the equipment and personnel to the underground site where the tunnel is being excavated. The dimensions of the primary tunnel are 13 meters in width and 8 meters in height. Eventually, the advance tunnels will be refitted later as evacuation and maintenance tunnels. 

According to one expert interviewed by Asahi, the area of bedrock that the tunnel will pass through is located at a nexus between two tectonic plates, and the friction between these two plates means that one of them rises 3-4mm a year, a substantial shift in geological terms. The pressure on the tunnel tube will constantly be affected. As the tunnel is excavated, some of this pressure is alleviated, thus causing possible deformation of the tunnel over time. 

JR Tokai says it will use controlled explosions to cut through the bedrock at sections of between 1 and 2.5 meters. These blasted sections are then connected and reinforced with concrete to form an arch using steel supports with thick bolts driven deep into the surrounding bedrock so as to distribute the pressure more evenly. The expert, however, points out that since the tunnel is being built through two faults and different consistencies of bedrock, challenges the construction of the Oshimizu Tunnel did not have to address, they don’t know how things will work out until they actually do it. 

It is this mixture of geological phenomena that was the actual reason for the original delay. Because the maglev has to run on a level track, the tunnel cannot be built in the direction of the faults, and thus creates a “fractal zone” wherein lots of ground water is released in the process. This is the problem that former Shizuoka Governor Heita Kawakatsu cited when he refused to sign off on the tunnel project, since this ground water affects the flow of the Oi River, which supplies drinking water and irrigation for many communities in Shizuoka Prefecture. JR Tokai itself estimated that during construction, the river could lose up to 2 tons of water per second, so Kawakatsu said he would not allow for construction until the company came up with a plan to retain the water. Initially, JR Tokai devised a scheme to capture the water and return it via pipes to the river, but not all of the water could be returned. A standoff ensued, and, spurred by JR Tokai’s accusations of intransigence on the part of Shizuoka Prefecture, the media scapegoated Kawakatsu as being the main obstacle for the maglev project’s inability to meet its deadline of opening by 2027. 

As some independent journalists and experts pointed out repeatedly, that deadline was never realistic in the first place, and so Kawakatsu’s fall-boy status was assured until he decided to quit the job due to an unrelated scandal and was replaced with someone more amenable to JR Tokai’s demands. In the meantime, the land ministry became involved since the project is considered in the national interest. Though the Chuo Shinkansen is the only shinkansen line that is nominally a private sector project, the government has loaned JR Tokai enough money to carry it out without having to pay any of it back until many years after the maglev is up and running.

The conservative estimate is that it will take ten years to complete the Shizuoka section of the tunnel, but a source close to the project told Asahi that he doesn’t think it will be completed in that timeframe. 

In its analysis of the “Shizuoka problem,” Asahi says that there was never a “relationship based on trust” between the three parties involved, meaning JR Tokai, Shizuoka Prefecture, and the land ministry. With JR Tokai, Kawakatsu’s attitude was probably understandable, since the company, according to Asahi’s investigation, never really acted in good faith during its negotiations with the prefecture, always responding to Kawakatsu’s requests with vague data and loopholes. 

The land ministry wasn’t much better. In 2019, a representative of the ministry’s railway bureau met privately with Kawakatsu to talk about an expert panel the ministry had formed to oversee the water issue. Kawakatsu initially agreed to listen to the panel but later rejected their involvement because he had come to suspect the members lacked “neutraility,” a situation that caused friction between Kawakatsu and the central government and which was pretty much at the bottom of Kawakatsu’s demonization in the mainstream media. Perhaps more damning was the governor’s alleged two-faced approach to the project: to other governors whose prefectures the maglev would affect, he insisted he was in favor of the project, but to the land ministry he was always suggesting they change the route to avoid Shizuoka. 

As it turns out, JR Tokai didn’t trust the land ministry either, since the maglev project’s initiator, the late JR Tokai President Yoshiyuki Kasai, was angered by the way the Japan National Railways was privatized in the late 80s and the resulting debt. It’s why he wanted to carry out the project without any government involvement. 

In the end, according to Asahi, this lack of trust between the three main players has been the greatest obstacle to completing the Shizuoka section, but in a sense the problems incurred apply to other sections of the tunnel construction. It’s just that these problems haven’t been openly reported by the media. One expert told Asahi that he has come to admire Kawakatsu because, unlike other governors, he addressed the obvious environmental risks involved. The problems Kawakatsu pointed out could very well remain problems in the future. 

In the third Asahi installment, published July 28, these other problems were brought up, including a loss of ground water along the Gifu section of the maglev tunnel that has negatively affected local farmers; subsidence surrounding the Shinagawa section of the tunnel that caused a surface roadbed to rise by 13 centimeters; and arsenic-contaminated soil that exceeds safety standards from the Sanchi Tunnel section in Nagano Prefecture that is being used for landfill in surrounding communities. 

The reason these problems haven’t been publicized as openly is that the prefectures themselves have more of a stake in the maglev since they are building stations along the route. Shizuoka will not have a station within its sector, which is why it can prioritize environmental concerns. So the main problems with these other prefectures is not the environmental ones involving ground water and removal of soil and bedrock that residents actually care about, but rather the economic ones caused by the delay in the opening of the line. JR Tokai shareholders are getting fidgety about the constant delays and added costs.

So Asahi’s coverage is significant in that, as a pillar of the mainstream media, its questioning of the project shows that it may be bucking the authorities. Usually, the media all fall in line in supporting large civil engineering projects, but the maglev’s problems have been apparent for too long. 

Coincidentally or not, the day before the Asahi series started, the paper published a letter to the editor from a 54-year-old company employee who drew parallels between the maglev and the supersonic Concorde passenger airplane, which was developed decades ago as the future of commercial air travel but due to feasibility issues has mostly been abandoned. “All the aircraft are now retired,” said the letter writer, “and there is no ‘next generation’ of airplanes.” Which just goes to show that once a major project like the maglev is launched, it’s impossible to stop, even if the demand for such a project evaporates over time. By the time the maglev is actually in operation, it may not have much of a purpose. It may even be obsolete.