Reclaiming Skies Above Nihonbashi to Cost ¥320 Billion


Nihonbashi is one of Tokyo’s most historic landmarks, but an expressway built directly overhead has long made this famous bridge a much less impressive sight. Some citizens state that they want to “take back the sky” above the renowned bridge; the cost of moving the offending road underground has been revealed to be at least ¥320 billion.

Sky-High Costs for Giving Nihonbashi a View of the Sky

At a July 18 meeting, officials from the Ministry of Land, Infrastructure, Transport, and Tourism (MLIT) and other parties announced that they had reached a funding agreement on a project to move an expressway in the city of Chūō, Tokyo, underground, opening up the famed bridge Nihonbashi to the sky for the first time in decades. Metropolitan Expressway Co., the company that manages and maintains the expressway in question, would cover ¥240 billion worth of the budget, while the governments of Chūō and the Tokyo metropolis would cover ¥40 billion. The remaining ¥40 billion is to be borne by companies involved in redevelopment of the surrounding area.

They are aiming to start construction after the 2020 Tokyo Olympic and Paralympic Games have concluded.

Nihonbashi is a landmark of considerable historical significance, marking the beginning of all major roads from the capital to other regions of the country. But views of the bridge are marred massively by the hulking elevated expressway lanes that keep it in perpetual gloom.

Back in 2002, a group led by Transportation Minister Ōgi Chikage began proposing that the Shuto Expressway, which runs over the bridge, be relocated. Four years later, Prime Minister Koizumi Jun’ichirō echoed similar sentiments when representing another group, this time calling for the road to be moved underground. Now, another 12 years later, the budget for such an undertaking has finally been settled upon, but as parties close to the project have pointed out, “We still don’t have the full picture of what this will entail.”

The meeting on July 18.

“We Still Don’t Have the Full Picture”

To move the 1.2-kilometer portion of the Shuto Expressway running over Nihonbashi underground, the committee devised a plan to help mitigate costs by routing part of it through the existing Yaesu Tunnel on the Shuto Yaesu Route. In order to do that, however, the committee needed to take into account one other road: the Tokyo Expressway, colloquially known as the KK Route.

The KK Route, which connects to the Yaesu Tunnel, is a toll-free road that runs approximately 2 kilometers from Shiodome and Shinbashi up through Yūrakuchō and Ginza. The space below it is lined with bars and tiny restaurants that have become almost synonymous with that part of the city.

The KK Route running through Ginza.In order to move the Shuto Expressway underground, the one-lane sections of the Yaesu Route would need to be increased to two-lane roads, its entrances and exits would need to be rebuilt, and other changes would be required to allow larger vehicles to travel on the KK Route.

However, the elevated KK Route is structurally unable to bear the weight of large size vehicles, and its twists and turns make it ill-suited to truck traffic. The committee indicated a need to discuss whether to retrofit the KK Route for larger vehicles or to build an entirely new road. Neither of these choices, though, is included in the ¥320 billion figure.

A source close to the project tells FNN, “The cost of redoing the KK Route would be substantial. We still don’t have the full picture of what this will entail,” ringing the alarm that despite a proposed budget of ¥320 billion, costs could balloon still more.

Putting the expressway underground comes down to how the KK Route will be revised.

The Danger of Budget Expansion

Another source close to the committee states that reconstructing the KK Route could end up costing tens of billions of yen as a project of its own, pointing to still more stratospheric costs for the Nihonbashi scheme overall.

The same source points out that even excepting the KK Route from calculations, there is no proof that the cost of moving the expressway into a tunnel would stay within that ¥320 billion figure. Nihonbashi and the river it crosses lie above all sorts of electrical, sewerage, and other infrastructure, not to mention the labyrinthian web that is the Tokyo subway network.

MLIT and other organizations believe that Japan has the technological chops it would take to stitch all of these various elements together over the course of construction, but a complex, massive project like this comes with no guarantee that it will stay within budget—before even considering the potential costs associated with redoing the KK Route or building a new road altogether. What is more, automobile ownership in Japan is set to decline in the coming years, meaning there will be fewer vehicles on the roads to pay the tolls that help defray costs. To cover the colossal budget of moving the road underground, the taxpayers of Tokyo and Chūō in particular would be called on to pitch in.

Are the costs associated with “taking back the sky above Nihonbashi” really worth it? With at least a preliminary budget having been released, it seems the next step in the process will be to make further investigations into the project and secure the understanding and consent of Tokyoites.

(Originally published in Japanese on FNN’s Prime Online on July 20, 2018. Text by Fuji TV City News Department and MLIT correspondent Aizawa Kōta. Translated by[© Fuji News Network, Inc. All rights reserved.]

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