Modern technology has made the impossible possible.
Through the sheer ingenuity of advanced innovations,
man has traveled to the moon,
built skyscrapers,
purified poisonous water
and created safe living sites in regions that were unlivable just a few decades ago.
However, it is not every time man gets it right. Sometimes, he gets it wrong and when he is wrong, things go bad…..really bad.
In a classic case of Mother Nature reasserting her dominance and will over the ecosystem that is called planet Earth,
a $20 billion airport appears to be sinking.
That airport is none other than Kansai International airport, adjudged to be one of the most sophisticated airports in the world.
Hello and Welcome to yet another exciting video on our Channel. In this episode,
we will relay to you what went wrong with the Kansai International airport
and how modern technology and human ingenuity can go wrong with potentially disastrous consequences. Let us begin!!
The Issue
The Kansai International airport was built on two artificial islands in Osaka Bay.
These islands are called artificial
because they are not natural but man made runways to allow for the landing and take off of flights.
Opened in 1994 to reduce the congestion on other airport facilities
like the one in Itami Airport in Tokyo,
when it was unveiled, it was hailed by local and international observers as a modern technological wonder.
Little did we know that decades later, the airport that cost billions of dollars is on borrowed time.
Borrowed time because the sprawling airport started sinking and sinking really fast at that.
Other Airports built on top of water
Kansai is not the only airport resting on an artificial Island,
though it was one of the first ever airports to be built on top of one. Not too long ago,
a new one was opened in Northern Istanbul, Turkey. This airport is built over a marshland somewhere in the Black Sea.
en there is the gigantic airport built on the Maldives Archipelago in the middle of the Indian Ocean .
What about the new runway that was opened last year?
The runway was built on top of an estuary in Brisbane River in Australia.
So Kansai is not the only one
but out of this list, it is the oldest and many other airports resting on artificial lands or waterways got their inspiration from Kansai
which is a worry for observers. But what actually went wrong?
The runway is sinking
Since 1994 when it was opened for commercial flights, reports have it that it has sunk 38 feet. I
mages of water invading the runway have sent observers into delirium
as the implication of the situation is becoming clearer by the day.
From all indications, it appears that the engineers who built the airport miscalculated, or simply just got it wrong.
At the time, they predicted that the island on which the airport was built would settle at some point at 13ft above sea level. This projection was billed the minimum gradient level to prevent flooding.
However in just 6 years, the 13ft above sea level projection was breached.
To prevent a further breach, millions of dollars has been spent and more money has been budgeted to stop the sinking of the airport.
However, many experts fear that the seawall will be breached by 2056 latest
and that the airport will sink by at least 13 more feet. If this were to happen regardless of what the engineers do,
that will lead to the flooding of the runway, and eventually it will be overrun by the Pacific Ocean leading to the eventual sinking of the airport.
The sinking of Kansai will be a technological disaster with environmental and economic consequences.
The Projections were wrong
According to the communications director of Kansai International airport, when Kansai was built,
The soil volume required to reclaim the land was estimated by experts based on soil subsidence timeline over half a century after the construction.
However what caught engineers by surprise was the difference between the actual rate of soil consolidation
and the estimated rate of consolidation. In layman’s terms, consolidation refers
to the rate at which new soil layers harden to form a stable consolidation after the soil has been deposited into a foundation. In the case of the Kansai airport, thousands of tons of soil was dumped into the foundations but from the look of things, it did not harden as well as it should have,
leading to a weak foundation that is threatening to collapse anytime soon.
How was Kansai airport built?
The airport was built on artificial land with a heavy runway and heavy buildings standing on the land. W
hat was once a water plain was transformed into a dry, sense foundation. To achieve this, engineers laid 5ft of sand on top of the clay seabed
after which they installed roughly 2.2 million vertical pipes nearly 16 inches wide.
Once the pipes have been drilled into the clay seabed
they loaded them up with sand to absorb moisture from the soil layers.
Then, fabrics were pushed into the pipes to soak up more moisture.
Some of the fabrics used included vertical drains and wicks. After some time, the pipes were removed but the drains were left in place.
The next step they took was to add new soil to the sand layer which they dredged from
Osaka Bay and from nearby mountains.
Some more were sourced from Korea and China to build up more layers.
As more soil was added to the foundation, moisture was absorbed
by the soil, wick and dense sand making the layers below the new soil layer non porous.
This system made the layers stronger and less likely to lose form. Furthermore,
a seawall was constructed to protect the construction area with 48,000 concrete rubble and blocks. The wall was anchored with heavy steel chambers and as the construction work continued,
more soil and sand layers were added to take the ground above 65ft of sea level.
Then and Now
When Kansai airport construction started in 1987,
constructors told the public that there was no cause for alarm and that the foundation would hold.
Three years later, by 1990, the Island had sunk by 27ft,
not the 19ft that was predicted. That was a further 8ft than was predicted.
To slow the sink rate, the region below the passenger terminal was excavated
and iron plates were inserted below hydraulic jacks to raise the columns. Unfortunately, these measures had very little effect.
They planned to readjust the jacks every 24 months where necessary but the expert could still not give an estimated shelf life of the airport.
Some experts like Gholamreza Mesri, an engineering professor at the University of Illinois Urbana Champaign
said that the airport may reach a danger point of 13ft above sea level as early as 2023.
He also believes that if a typhoon or a hurricane were to strike Kansai Island directly, the effect will be catastrophic since the waves will breach the sea wall, overrun the runways and airport buildings and sink them all.
Another thing that’s a cause for concern for engineers is the unevenness of the ground because areas of the foundation are sinking while other parts remain firm and in place. For example, at
the center of the passenger Terminal in location 1,
the basement level is sinking much faster than the areas where the terminal building is resting.
And unfortunately, paving the runways with asphalt to level the gradient has not been very successful.
Repairs cost more than the construction
In a classic tale of being penny wise and pounds foolish, the Japanese government and engineers are learning the hard way. W
hen the project was completed in 1994, the total cost was $8 billion.
However, by 2008, the cost of repairs had raised the budget to $20 billion,
more than the required cost to build another brand new airport. For all the value of having an airport that is close to sea, the valid question many have asked is why did the airport had to be built on reclaimed land?
The answer is anybody’s guess but the general commentary at the time was that the transport ministry wanted a land that was very close to the city so travelers could take advantage of the transport routes.
In addition, the high cost of acquiring an inland property to build the airport was too much for the ministry to bear
in addition to the negative environmental impact such a move would have on residents.
For these reasons and more, planners decided to sand fill the area where the airport currently lies and
they creates extensions for the runways.
Unfortunately, the airport has become very expensive to maintain, but one thing everyone can admit is that it has done its job andcontinues to do so. So far so good,
Kansai remains one of the busiest airports in Asia with more than 26 million passengers passing through the airport every year.
In 2001 it received a special honor from the American Society of Civil Engineers for its monumental technological features.
What the future holds
No engineer can say for sure what will become of Kansai.
Is it salvageable? Will it sink into the Pacific Ocean? If it will, how many more productive years does Kansai have?
The flawed projections were wrong from the outset and so far, a lot has been said about the future of the airport
Billions of dollars have been spent in repairs and more than half a billion was reinvested into repairs starting from 2019.
Since then, 3 separate repairs have been conducted
and engineers hope the sinking of the runway will stop, at least for the foreseeable future.
However, if Kansai becomes unsalvageable and there is a need to evacuate the airport, it will be a sad end to a monumental structure
that captured the imagination of the entire world for close to three decades.
Do you think Kansai airport is on borrowed time or can the ingenuity of the Japanese engineers prevent the impending catastrophe? L
et us know what you think by leaving a comment in the comment box. Thanks for watching the video and don’t forget to subscribe to our channel and like the video. Cheers