- Kansai International Airport is sinking into Osaka Bay due to subsidence issues
- The airport surface has dropped 3.84 metres, with total sinking of 13.6 metres since 1980
- Engineers are stabilising the structure with $150 million spent on seawalls and sand drains
The Kansai International Airport (KIX) in Japan, built on two artificial islands in Osaka Bay, was once hailed as an engineering marvel. It is currently sinking.
Japan is taking immediate action to stop additional damage to the airport, which is experiencing continuous subsidence issues and sinking into the Osaka Bay.
The surface of the island has dropped 3.84 metres, raising long-term questions regarding the sustainability and storm resistance of the airport, The Straits Times reported. Not just that, the project has sunk about 13.6 metres since the construction began in 1980.
The airport was designed to float on soft seabed clay using sophisticated ground improvement techniques when it opened in 1994. However, early subsidence exceeded predictions, dropping about 12 meters in the first 8 years of operation.
The airport's soft clay foundation is unable to sustain its enormous weight. Rising seas and natural forces are gradually drawing the engineering marvel closer to the depths, posing a threat to its very existence in future.
Having maintained a perfect record of no lost luggage for over ten years, the airport was named the world's best airport for luggage handling in 2024.
The Japanese airport was initially praised as a model of regional economic rivalry and a significant solution to overcrowding, aimed at reducing congestion at the nearby Osaka airport. Since then, KIX has expanded to accommodate both domestic and international travel, growing into an important aviation centre.
KIX has also received international recognition for its staff, efficiency, and architectural design. Approximately 30.6 million passengers travelled to 91 cities in 25 countries in 2024, passing through its terminals.
The 2018 Typhoon Jebi, which brought catastrophic flooding and highlighted the importance of addressing the sinking problem, made the airport's vulnerability evident. It was temporarily closed because of flooding brought on by the storm.
Engineers are concentrating on stabilising the structure to stop additional damage and guarantee the airport's long-term sustainability.
Operators have invested more than $150 million to strengthen seawalls and create vertical sand drains to alleviate water pressure from below in order to counteract the ongoing sinking.
According to the most recent data, published in December 2024, the artificial island's average subsidence, as measured at 17 different locations, was only 6 cm.
On the second island, however, the ground surface has fallen 17.47m since construction started. In 2024, the average subsidence at this island's 54 measuring locations was 21 cm.
