“Vocational Service Month” Meeting
Development of the Kanjo 2 Line
October 8, 2014
Mr. Ryoichi Yokomizo
Executive Advisory Engineer
(Chief of the Construction Bureau),
Tokyo Metropolitan Government
The Kanjo (loop) 2 Line is an urban planning road connecting between Kanda Sakumacho and Ariake. A part of this Line is called the Sotobori-dori. The Shinbashi-Toranomon section of the Line just opened on March 29th, while further construction work is under way in the bay-area from Tsukiji to Ariake. As the Line is planned to run by the Olympic Stadium, the Olympic Village and the press center set up in Ariake for the 2020 Games, there are suggestions to name the Line the “Olympic Road.”
A new Tsukiji Ohashi bridge is being constructed. A 3,000-ton-vessel was used to hang and place successfully an enormous bridge component that measured 120 meters long within the error range of merely 5 mm on each side. As you can see, the construction is based on advanced technology and skills of our country.
The Kanjo 2 Line is unique in utilizing the Multi-Level Road System that allows for the construction of roads and buildings in the same place by making the road run through the building or run underground beneath the building. The main road of the Kanjo 2 Line runs through the high-rise Toranomon Hills building, partly contained within the underground tunnel which allows highly efficient use of land space. The Toranomon district is being redeveloped, where two more high-rise buildings will be constructed to house 942 property owners in the vicinity.
The urban planning was conceived back in 1946 and has been revised several times. The Kanjo 2 Line was initially planned to be 100 meters wide. Due to financial constraints, the road width was changed to 40 meters in 1950. In 1998, it was further revised to construct a two-layer road, which circulates both above and below street level.
The Tokyo Metropolitan Government implements the “Tokyo Champs-Elysées Project,” which aims to develop an international promenade equivalent to the Champs-Elysées in Paris by developing fashionable storefronts and outdoor cafés along it. A 13-meter-wide sidewalk and the bicycle-lane constructed in Toranomon area are expected to attract many visitors and tourists and serve as a relaxing oasis amidst the congested metropolis. It is also envisioned that the Project will make it easier for merchants to set up outdoor recreational facilities on roads and/or river banks. In Japan, there are strict regulations for the occupation and use of roads and rivers, which have discouraged effective utilization of public spaces so far. I believe we must enhance our future urban development projects towards creating an enjoyable town by making good use of public spaces to respond to the changing times. The Project also aims to maintain and improve the town with reduced use of taxpayers’ money. One initiative is to collect occupancy fee from the merchants and use it for road maintenance.
Now, let me highlight some concrete measures taken for the maintenance and safety of the Kanjo 2 Line. You might recall the tragic ceiling collapse at the Sasago Tunnel. The accident may have been caused by inadequate inspections and maintenance that had failed to detect irregularities, including superannuated bolts and metal rods that suspended the ceiling. After this accident, the Tokyo Metropolitan Government reviewed the basic principles of its maintenance work and has been trying to make the work easier or not even necessary. For example, we have installed lightings and ladders for easier inspection. The new Tsukiji Ohashi bridge is installed with a passage that allows inspection by walking and not by traditional suspended scaffolds or special vehicles. We have also applied corrosion-resistant paint to the bridge. There are plans to introduce a new inspection system that utilizes the latest ICT technology.
The ventilation tower of the Kanjo 2 Line is covered with a glass wall and looks beautiful at night reflecting illuminations. Its surface is coated with photo-catalytic paint. This self-cleaning material has excellent dirt repellent properties, enabling rainfall to clean the glass. The ventilation tower contributes to maintain the scenery as well as to reduce the cost and burden for its maintenance.
It took as long as 68 years to open the Shinbashi-Toranomon section of the Line. We are grateful for the patience, understanding and collaboration of the people in the area. Construction work is currently underway in the bay-area to make the Kanjo 2 Line.the axis of transportation by the time Tokyo hosts the Olympic and Paralympic Games. I sincerely hope the Line will be loved by the people in Tokyo with its facilities and amenities.