The start date of the new high-speed maglev train that will run from Tokyo to Nagoya has become increasingly uncertain, as long-running environmental disputes with the Shizuoka prefectural government leave the project at a stalemate.

Central Japan Railway Co.'s Linear Chuo Shinkansen project is planned to link Tokyo and Osaka with trains traveling up to 500 kilometers per hour. But a small area on the section between the capital and Nagoya has proved a stumbling block for the major project, due mostly to opposition by Shizuoka Gov. Heita Kawakatsu.

The Nagoya to Osaka section is penciled in for completion in 2037, while the Tokyo to Nagoya portion was initially targeted for 2027 but is now officially "2027 or later" following the prolonged schism between the train operator and the local government.

Photo taken on Jan. 15, 2024, shows a maglev train tunnel work site in Kawasaki near Tokyo, shown to the media ahead of full-fledged drilling beginning around September. Central Japan Railway Co.'s Linear Chuo Shinkansen bullet train service will link between Tokyo and Osaka for about one hour. (Kyodo) ==Kyodo

If the over 9 trillion yen ($60 billion) project is completed, it is expected to trim journeys from Tokyo's Shinagawa terminal to Nagoya to 40 minutes, and 67 minutes from the capital to Osaka -- under half the fastest current times by shinkansen bullet trains.

Using superconducting magnetic levitation technology, maglev trains run about 10 centimeters above the track. During a manned test run on an experimental track in Yamanashi Prefecture in 2015, a prototype reached 603 kph.

JR Central's President Shunsuke Niwa maintains the new line can serve as a vital backup between the country's three major metropolises in the event of major disasters such as a powerful earthquake involving a potential tsunami. The project "could bring about significant benefits and developments for the Japanese economy," he said.

Unlike the largely above-ground Tokaido Shinkansen that runs a similar but more coastal route, 86 percent of the maglev line's 286-kilometer course between Tokyo and Nagoya would be in tunnels, necessitating significant excavation work. Just 8.9 km of the tunnels are set to pass through Shizuoka Prefecture.

Amid controversy over the line's tunnels passing through the prefecture, Kawakatsu has, along with local communities, pushed back over environmental issues including what is known as the "water problem" involving the effects of construction on the Oi River.

Opposition in Shizuoka Prefecture emerged from fears the planned tunnel construction for the line could adversely affect the overall volume of water that passes through the river.

JR Central has not yet been able to start tunnel construction despite the approach of the initial targeted start date.

Signs the impasse over the issue could be overcome raised the prospect the maglev shinkansen project may be able to go ahead. The catalyst in overcoming the disagreement was a JR Central-led proposal to work with the prefecture's Tashiro Dam.

Under the agreement, the dam would, for a fixed period, control the amount of water it holds to ensure the normal flows out of the prefecture are secured. The plan was welcomed by local communities and subsequently approved by the prefectural government in November.

But as one door opened, another shut in the form of a report from a Ministry of Land, Infrastructure, Transport and Tourism panel in December that acknowledged the development could damage the ecology of mountain ranges known as the Minami Alps, or Southern Alps, which run from central Nagano Prefecture and down through Yamanashi and Shizuoka prefectures.

Kawakatsu, who has been governor since 2009, had once described himself as a major supporter of the maglev train project. But the panel's report has only strengthened his opposition.

"The proposed route passes through the Minami Alps, a biosphere reserve recognized by the United Nations Educational, Scientific and Cultural Organization. The government panel report says there will be damage to the environment, so the issues are clear," he said.

Although the Linear Chuo Shinkansen's route is planned to pass through Shizuoka Prefecture, services will not stop in the area, while other prefectures on the route -- Kanagawa, Yamanashi, Nagano and Gifu -- will have stations.

In a bid to encourage Kawakatsu to drop his opposition, the central government issued an estimate in October showing that there could be 1.5 times more regular shinkansen services that stop more frequently, including in Shizuoka Prefecture areas, if the maglev line goes ahead.

Tokaido Shinkansen services have six stations in Shizuoka Prefecture.

But Kawakatsu snubbed the calculations as "poor, the kind of estimate even a grade schooler could do."

On Dec. 28, the transport ministry approved a submission from JR Central to change the Nagoya leg's completion date to "2027 or later," citing opposition in Shizuoka as the reason for the delay.

But Kawakatsu dismissed the suggestion that his prefecture is responsible for the project being pushed back from its 2027 open.

"Can they complete construction on other parts of the line by 2027? It appears the Shizuoka section is being used as a scapegoat to say they can't do it. I'd like to see JR Central offer some clarity on the situation," the governor said.

Kawakatsu has previously called on the train operator to prioritize work to enable it to open part of the line, a stance he has pushed more forcefully in recent years.

His remarks prompted JR Central to hold a press conference in January, in which the company said the governor's remarks were off the mark.

"We are moving ahead with the project as existing shinkansen infrastructure has aged, and to safeguard against future disasters. We are not considering opening only a section of the line," it said.

While all other prefectural governments on the planned maglev train route are pushing for the launch, Shizuoka's position not to allow the tunnel construction is leaving the cutting-edge project's future uncertain.

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