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Maglev tunnel construction faces delays over river concerns in Shizuoka Pref.

The Oi River system is seen near its headstream in Aoi Ward, Shizuoka, on Aug. 2, 2018. (Mainichi)

SHIZUOKA -- There are no prospects that construction of a tunnel through the Southern Alps here in Shizuoka Prefecture for a high-speed magnetically levitated (maglev) train line will start anytime soon because the prefectural government is concerned about the project's impact on water resources.

Central Japan Railway Co. (JR Central) is set to start preparations to build the tunnel as early as the end of August. However, the Shizuoka Prefectural Government, which will not benefit directly from the superexpress line because no maglev train station will be built in the prefecture, does not appear ready to make any compromises.

The Southern Alps Tunnel, which will be about 25 kilometers long, will pass through the three central Japanese prefectures of Yamanashi, Shizuoka and Nagano. However, construction work on a section in Shizuoka extending about 8.9 kilometers has not been started. The area is situated near the upper reaches of the Oi River system. Spring water that will be generated as a result of excavation work will flow toward Yamanashi Prefecture through the tunnel.

JR Central estimates that the amount of water flowing through the Oi River and its branches will decrease by up to 2 tons per second as a result of the construction work. The company presented a plan to build a channel to direct the same amount of water back into the Oi River to the prefectural government in January 2017.

In June this year, the Shizuoka Municipal Government agreed to cooperate with JR Central over the construction of the tunnel -- which would run through the city of Shizuoka. Under the accord, the railway operator will fully foot the cost of building a tunnel for construction work, through which ordinary vehicles will be allowed to pass. The municipal government apparently agreed to the plan because the tunnel would increase convenience in areas along the upper reaches of the Oi River, where depopulation is progressing.

A prototype train is seen on the experimental line for high-speed magnetically levitated trains in Tsuru, Yamanashi Prefecture in this file photo taken on Nov. 13, 2017. (Mainichi)

Meanwhile, residents of areas further downstream where the population is greater use water from the river for their daily lives and for farming, and cannot get over their concern that the tunnel construction could decrease the volume of water in the river. Skeptics have pointed out that the basis for the railway operator's estimate that the water volume will decrease by 2 tons per second is unclear.

In July, JR Central said that the amount of spring water generated though excavation may be greater than the decrease in river water, and offered to use electric pumps post-construction to divert the necessary amount of spring water into the river.

On behalf of residents of areas downstream, the prefectural government has stayed tough in demanding that JR Central promise to permanently pump "the full amount" of spring water back into the river and sign agreements with land improvement districts and other bodies that may utilize water sources.

JR Central is apparently puzzled at the prefectural authorities' demand, with one official saying, "What does 'the full amount' mean?"

The prefectural government set up a panel of experts in August to analyze the impact of the tunnel construction on the environment, such as water in the Oi River system, stepping up its confrontation with JR Central.

Noting that the water issue could affect one-sixth of the prefecture's population, Gov. Heita Kawakatsu said, "It'll be difficult to reach an agreement by the end of this fiscal year, when the panel is scheduled to draw a conclusion."

Contributing to the prefectural government's persistence are prefectural residents' discomfort with the fact that trains on the new maglev line between the capital and the major western city of Osaka will not stop in the prefecture.

JR Central, which also operates the Tokaido Shinkansen bullet train line, intends to increase the number of trains that will stop at stations on the line in Shizuoka Prefecture after the maglev line opens. However, an official of a municipal government located downstream on the Oi River remains skeptical.

A JR Central official said in a meeting with those utilizing water from the Oi River system, "There are no rules stipulating that we can't begin construction without signing an agreement with you. We'd like to provide explanations of our project whenever necessary."

(Japanese original by Nobuyuki Shimada and Daichi Matsuoka, Shizuoka Bureau)

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