how is it going?
Elimination of utility poles in Tokyo March 10, 16:36
A utility pole that collapses on the road and blocks the way of cars and people.
In the Great East Japan Earthquake 11 years ago, 28,000 trees collapsed, hindering rescue operations.
In preparation for an earthquake directly beneath the Tokyo metropolitan area, which is expected to be even more serious, the Tokyo Metropolitan Government is promoting the elimination of utility poles.
Governor Koike is also focusing on this measure, but when I interviewed the site, I could see the challenges for its realization.
(Kazuyuki Ogaki, reporter of the Tokyo Metropolitan Government Building)
The scenery of the town that you often see, in the event of a disaster ...
Utility poles and electric wires lined up on narrow roads.
Houses are approaching on both sides of the road, and many cars pass by avoiding utility poles from daytime.
This is a densely populated area of wooden houses in Arakawa Ward, Tokyo, the so-called "wooden area".
This kind of scene is often seen not only in Tokyo but all over the country.
Imagine that a utility pole has collapsed, and I feel that not only will fire engines not be able to enter, but it will also hinder the evacuation of people.
"Undergrounding" is also a pledge of the governor
"Eliminating utility poles" by eliminating these utility poles and burying electric wires in the ground.
Governor Koike is focusing on that policy.
In the 2016 Tokyo Governor's election, we made "zero utility poles on the road" one of our pledges, and we have continued to do so even after we were elected.
One of the reasons for focusing on "no utility poles" is that utility poles are vulnerable to disasters.
In the Great East Japan Earthquake 11 years ago, about 28,000 utility poles collapsed nationwide, causing power outages and further hindering fire extinguishing and rescue.
An earthquake directly beneath the Tokyo metropolitan area is expected to cause even more serious damage in the "tree-dense area."
Of the 23,000 deaths in the worst case, 70% are expected to be damaged by fires mainly in these areas.
For these reasons, Governor Koike has been trying to accelerate the utility pole-free project that Tokyo has been conducting since 1986.
Tokyo is a "top runner", but ...
How far has the elimination of utility poles progressed?
The clue is the data of the Ministry of Land, Infrastructure, Transport and Tourism's "Undergrounding Rate" at the end of 2020.
Comparing the special wards and ordinance-designated cities, Tokyo's 23 wards are the most advanced, albeit 8.2%.
This is followed by Osaka City at 5.6% and Nagoya City at 5.1%.
It can be said that it is more advanced than other cities in the country.
On the other hand, when you look at the comparison with overseas, the impression changes.
In London, Paris, Hong Kong, and Singapore, the utility pole-free rate is 100%, which means that the city is far behind the fact that there are no utility poles.
Subsidize the "full amount" of construction.
Nevertheless…
According to the person in charge of Tokyo, measures have been relatively advanced in the last few years on "national roads" and "prefectural roads", that is, wide arterial roads.
As of the end of 2019, about 60% of the construction work has been completed in the 23 wards of the metropolitan roads that are planning to eliminate utility poles.
On the other hand, it is the countermeasures for "ward, city, town, and village roads", especially "tree-dense areas", that all the issues are addressed.
Since 2019, three years ago, the Tokyo Metropolitan Government has been cooperating with the national government to subsidize the "full amount" of the work to bury electric wires for the "no utility poles" carried out by the municipalities in Tokyo.
However, there still seems to be a big challenge.
What is the reason why even if you "subsidize the full amount", it will not proceed?
The bottom of the road is full
It is another ward road in Arakawa Ward.
It is a typical "wooden area" with densely populated houses and narrow roads.
"Under this road, it's already full." The
person in charge showed me the condition that I wouldn't broadcast it, which is a cross-sectional view under the road.
Gas pipes and water and sewage pipes were buried in the basement.
In order to promote "no utility poles", it is necessary to bury electric wires under the roads that have become "stuffed".
It's not so easy because it puts in a wide variety of cables such as wires, communications, and television.
In addition, this concrete box, called the "special part", holds the connection between these cables and the lead-in to the house.
It is said that it is indispensable for maintaining the strength of weak connections, but even a small type has a width of about 2 meters.
It is said that it is extremely difficult to get under a narrow road.
Construction was completed in 6 years, 630 meters
On the ward road that I was guided to, I was able to fill the electric wires by combining it with the construction to widen the road for disaster prevention.
This is because the width of the road has been widened to 6 meters, and there is a space under the road for electric wires to pass through.
However, it took more than 10 years to acquire land to widen the road and have the houses on both sides retreat from the road.
In addition, construction work was also carried out to investigate the underground situation.
The burden on road managers is said to be about 350 million yen per kilometer, but it cost nearly twice as much.
Therefore, the burden on the ward is also incurred.
Arakawa Ward is considering eliminating utility poles on ward roads of about 20 km, mainly in densely wooded areas.
However, it took about 3 kilometers to complete the construction over 6 years.
Construction was completed at 630 meters.
How does Arakawa Ward view this situation?
Arakawa Ward Disaster Prevention Urban Development Department Infrastructure Development Section Chief Akihiko Morokaku
"Residents are saying,'Please do it with a sense of speed.' I have a strong consciousness, but it is not easy to speed up the construction. Also, if you repeat the construction of digging and burying, the burden will be heavy, and it would be helpful if the country and the capital could help a little more. Is the real intention. "
Development of new technology to promote the elimination of utility poles
While the problems of construction period, construction cost, and space were confronted, new technology was being developed as a clue to the solution.
The underground "visualization" technology was developed by an infrastructure equipment company in Ota Ward, Tokyo.
By simply moving a special machine on the road, the positions of gas pipes and water pipes in the ground can be grasped by electromagnetic waves and expressed in 3D.
By making it 3D, it is not necessary to repeat prospecting to grasp the underground situation, which leads to shortening of construction period and cost reduction.
In addition, because it can be seen three-dimensionally, it is possible to design to fill the electric wires while dodging other lifelines up, down, left and right.
Infrastructure equipment company "Geo Search" Chairman Hiroshi Tomita
"In the wooded area, pipes whose lifelines and uses are unknown are complicated like" spaghetti. " I think that we can steadily lead to disaster mitigation by prioritizing the selection of places where we can do smoothly. "
The person in charge in Tokyo is ...
How does the Tokyo Metropolitan Government perceive that it takes time to eliminate utility poles, especially in the "undergrounding area"?
I asked the person in charge.
Mikio Okabe, Manager, Utility Pole-Free Project, Tokyo Metropolitan Government Bureau of Construction
"It is certainly a difficult problem to eliminate utility poles on narrow roads. We also hold technical study meetings with wards, cities, towns and villages, so we will proceed with technological development with the help of the private sector. , I want to introduce it to the ward, city, town, and village. "
Experts ...
Experts point out that in order to promote the elimination of utility poles on narrow roads such as "underground areas," it is necessary to consider methods that are easy for local governments to use.
Tetsuo Yai, Vice-President of Tokyo Institute of Technology
"With the conventional construction method, if the burden of the electric wire company is added, it will be 500 million yen per kilo, and even if consensus can be reached with the residents, it will take 7 to 8 years, so from the viewpoint of disaster prevention. That's still difficult. It can be achieved by changing the means depending on the location, so the national government and the capital must consider more schemes that expand the options of local governments. "
Eliminating utility poles Searching for all means
"Measures for prefectural roads are not enough." The
Tokyo Metropolitan Government is considering expanding the scope of subsidies not only to municipalities but also to private roads, and it is a fact that I feel the "seriousness".
However, in the process of interviewing, it became clear that there are problems that cannot be solved by cost alone.
Disasters such as the earthquake directly below the capital do not wait for countermeasures.
I think it is necessary to explore every possible method and take measures.
Kazuyuki Ogaki , a reporter for the
Tokyo Metropolitan Area , joined the
station in
2017 after working as a newspaper reporter.