This $19 Billion Airport Is Slowly Sinking Into the Ocean

The airport, which serves Japan’s second-largest city, Osaka, was built on top of the water over three decades ago. However, it has sunk over 38 feet since then, and experts surmise parts could be fully submerged by 2056.

Many were quick to say it was affecting the trade of the region. So, to compete with locations such as Tokyo, a new airport would need to be built. However, there was one problem: the local Kansai airport lacked any space to extend.

Construction began in 1987, and following seven years of work and £15 billion ($19 billion), the new Kansai airport officially opened to the public in 1994.

However, the airport was soon subject to Japan’s harsh weather, and many natural disasters came one after another. Just one year after opening, it was partially damaged by the Great Hanshin Earthquake. In 2018, seawater flooded the runways after a typhoon swept through the area.

Ordinary life in Japan is often interrupted by natural events both large and small. While people have adjusted to the frequency of these disasters, they can still have profound negative impacts.

Japanese residents experience around 1,500 earthquakes yearly, which equates to around four per day on average.

These are a tropical storm that impacts Japan mostly between August and October. Residents experience a deluge of rain and high-speed winds. They cause significant damage to homes and injure tens of people every year.

It has a high concentration of active volcanoes spurred on by tectonic activity in the region. Experts consider Japan’s active volcanoes relentless, with large eruptions occurring at least once every 30 years. The country has 111 active volcanoes near its land area.

As the earth shifts, it causes flowing mud and land to overwhelm buildings and city streets. Residents have to deal with water supply interruption and roadways being obstructed. Landslides can also affect the foundation of buildings, causing them to sink.

Engineers predicted that Kansai airport would slowly sink over 50 years but eventually stabilize once it reached 13 feet above the level of the Seto Inland Sea. However, if it sank any further than this, its surrounding sea wall would no longer be able to hold back the waves, and the airport would slowly flood and sink under the ocean.

Cities have a large number of buildings, which are difficult to replace when the soil beneath them starts to become weak. Weakened foundations make it easy for heavy buildings to start sinking in the ground.

One solution was to raise the perimeter sea wall at an additional cost of over $120 million. But experts say it’s probably a little too late to save the airport.

Delaying flooding gives residents more time to evacuate to higher ground. It also helps Japanese infrastructure not get overwhelmed quite quickly by a sudden deluge. Japan’s seawalls are notably strong and developed because of the frequency of weather events.

“When the Kansai airport was constructed, the amount of soil to reclaim the land was determined based on necessary ground level and subsidence estimation over 50 years after the construction,” he said.

Next, over 2 million pipes were laid, each around 16 inches in diameter. The pipes were then hammered into the clay seabed before being filled with sand, all of which aimed at creating a solid foundation. Yet it appears to have failed.

If the ground beneath a building becomes weak, it can cause cracks to form which cause damage to the building. Once a foundation has become weak it may be inevitable to abandon the building rather than trying to fix it.

Workers were even instructed to hollow out various sections underneath the terminals and even tried to raise the height of the airport columns using hydraulic jacks.

Land subsidence is difficult to reverse given the the situation in the area. Huge effort would need to be put into replacing groundwater and strengthening the soil underneath the foundation. These efforts would require coordination from the government and maybe ultimately fruitless.

It appears the once thriving airport, which could see over 30 million passengers per year, may soon sink beneath the bay of Osaka.

According to the Japan Meteorological Agency, the sea level rise per year is going up. At the beginning of the 1900s sea levels were going down, but in recent years the sea levels have been rising at a rate of more than 60 mm yearly.

However, problems may arise sooner. The airport is currently sinking in sections, and soon, the runways and other portions of the artificial island may be fairly uneven, possibly resulting in safety hazards.

Now, people can enter Japan and get connected right to popular destinations like Kyoto, Osaka, Nara, and Wakayama. It is currently the third busiest airport in Japan.

Skytrax won the awards for World’s Best Airport Staff, Best Airport Staff in Asian, and World’s Best Airport Baggage Delivery. During 2022, Kansai were awarded first at the World Airport Awards for “World’s Best Airport Baggage Delivery” and “World’s Best Low-Cost Terminal.

The ends of the main building are sinking at a slower rate. As Osaka is Japan’s third-largest city, engineers are running out of time to devise a long-term plan for one of Asia’s busiest airports.