photo by kajima.co.jp
Japan enjoys its abundant water resources, which, on the other hand, means that people have to come to terms with its wet and humid climate. Heavy rain can cause a severe disaster with rivers flooding the neighbouring areas. A burst in the embankment of the Kinugawa River in September 2015 is still fresh in our memory. “Metropolitan Area Outer Underground Discharge Channel” is created as a sturdy guardian that helps us get along well with the water resources which occasionally can become a threat to our life. And this channel is now attracting people’s attention. The stories of a gigantic temple emerged underground have gradually spread among people, which now attracts many curious minds all across Japan. The true identity of this “gigantic temple” is a huge underground discharge channel. Built at the depth of 50 metre underground, it is the crystallisation of the best engineering technologies in Japan. This architecture is worth seeing once in a lifetime – you will surely be awed by its overwhelming presence.
A Gigantic Temple Underground
This huge underground water infrastructure is built in Kasukabe, Saitama. The channel would store flooded water from small and mid-scale rivers until it is discharged into a larger river. By doing do, the channel mitigates flooding disasters and prevents an embankment from bursting.
The main water tank made of concrete extends 6.3 kilometres and it is built even deeper in the ground than subway lines. You will be awed into silence at the sight of its mindboggling scale. This other-worldly place far away from the everyday life may look like a huge cave yet to be explored by a man or a subterranean shelter to protect human being from the end of the world. It is different from any historic ruins you might have seen. This main water tank, which can only be described as “a subterranean temple”, proudly presents the size of a large athletic stadium; moreover, the height of the ceiling is 18 metres. The entire space is sustained by 59 columns which overall weigh 500 tons. The columns might remind you of the oldest and largest cryptomeria tree in Yakushima Island. Visitors are certainly impressed by its other-worldly atmosphere this space offers.
The shaft even accommodates the Statue of Liberty?!
Another highlight of this underground discharge channel is the shafts which swallow the flooded water. Each of them is 30 metres in diameter and 70 metres in depth. It is fair to describe them as massive cavities in the earth. It can accommodate the Statue of Liberty or a space shuttle, let alone a building of a regular size. You might feel dizzy just by looking down inside. The tank is equipped with five of such shafts that lead flooded water to the channel.
The Brilliant Capacity which Promises the Watertight Defence
The underground discharge channel is not only proud of its size but also its capacity. It can accommodate 670,000 square metres of water at maximum, which is equivalent to the half volume of Tokyo Dome. The water collected in this tank will be discharged in the Edogawa River at the rate of 200 square metres per second. It is equipped with a massive turbine with a capacity of 14,000 horsepower that is capable of discharging huge amount of water at a time. These figures may not be easy to grasp, but it means that this facility can discharge a large amount of water that is equivalent to a full 25-metre swimming pool in a second. Doesn’t that sound reliable enough to protect the population in the Metropolitan area from flooding?
Do pay a visit!
The main tank of the Metropolitan Area Outer Underground Discharge Channel is open for visitors for free. It is open between Tuesday and Friday and there is no minimum number for the visitors. Please note that you will be climbing down more than 100 stairs as part of the tour. Be prepared to explore the subterranean world – avoid wearing sandals or heels. Of course, the tour into the main tank is not available when it is in use due to the heavy rain. In such occasions, you can visit “Underground Exploration Museum RyuQkan” to experience what it is like to be in underground. If you wish to see the gigantic temple that protects the life of residents in the Metropolitan area, then do plan a visit!
Contact:
Metropolitan Area Outer Underground Discharge Channel
