October 22, 2020

Akahata editorial (excerpts)

A city road in Tokyo’s Chofu City under which the tunnel of the “Tokyo Outer Ring Expressway” project was being excavated on October 18 suddenly caved in. The Chofu City government requested the government and the project operators to determine the cause of the accident as early as possible and to take measures to secure residents’ safety. Thorough investigation of the geological formations below the locations where tunnel excavation machines operate is essential.

The Tokyo Outer Ring Road scheme is a plan to construct an 85-km-long ring expressway connecting areas within a 15 km radius of central Tokyo. It is being carried out as a joint project of the Ministry of Land, Infrastructure, and Transport, East Nippon Expressway Company, and Central Nippon Expressway Company. In the current construction area, a tunnel is being built in the deep underground—40 meters below the ground or deeper—to construct the road. The accident site is in the construction area.

After a shield machine used for tunnel excavation on September 14 passed around 50 meters below the accident site, vibrations and noises were reported in houses nearby. Cracks appeared in walls and roads. Japanese Communist Party Dietmembers and local assembly members on October 7 urged the Land Ministry to suspend the construction work and check the condition of the bedrock. However, the construction was continued until the accident occurred. The cave in area is around five meters across and five meters deep. The accident could have been fatal.

The use of the deep underground became possible after the special measures law on pubic use of the deep underground took effect in 2001. As a result, underground 40 meters deep or below can be utilized for public purposes without having to purchase land or obtain landlords’ consent.

In urban areas, there are various networks of subways, water pipes, and other infrastructure under ground. The special measures law is aimed at utilizing deep underground areas where there are usually no artificial structures for large-scale development projects. During Diet deliberation on the law, safety concerns and the lack of a system to reflect local residents’ opinions of development projects became major issues.

Residents living near the outer ring road construction site have filed a lawsuit in order to have the national and Tokyo metropolitan governments retract their approval for the use of deep underground areas to construct the outer ring expressway. The national government should listen sincerely to the concerns of residents. The construction work must not be hastily resumed while the cause of the accident has yet to be determined.