Kansai International Airport (KIX), inaugurated in 1994, was hailed as an engineering feat, being the only truly floating airport in the world. Constructed at a staggering cost of over $20 billion, it has become a vital hub for both passenger and cargo airlines, serving nearly 70 passenger carriers and over 20 cargo airlines as of 2025. Despite its success, the airport faces a significant challenge: it is sinking into the sea at an alarming rate.
Current Status and Statistics
- Airport Codes: IATA: KIX, ICAO: RJBB
- Operator: Kansai Airports (Orix-Vinci consortium)
- Runways:
- Runway A: 3,500 meters
- Runway B: 4,000 meters
- Passenger Traffic (2023): 25.9 million
- Airline Hubs: Includes major carriers like ANA, Japan Airlines, and FedEx Express.
In 2023, Kansai recorded 169,774 aircraft movements, serving 25.9 million passengers, a recovery from the pandemic but still below pre-pandemic levels of 29.4 million.
The Sinking Dilemma
Kansai Airport was built to alleviate congestion at Osaka’s Itami Airport (ITM) by creating an offshore facility. However, the construction posed significant challenges due to the deep alluvial clay seabed, which was prone to settling. Engineers anticipated some sinking, but the actual rate exceeded their estimates. By the time the airport opened, it had already sunk 27 feet, significantly more than the projected 19 feet.
To combat this issue, approximately $150 million has been invested in reinforcing the airport’s seawall and employing hydraulic jacks to raise the foundation. While the sinking rate has decreased from over 19 inches per year at its opening to about 2.3 inches in 2023, the uneven sinking across the site complicates maintenance efforts.
Future Projections and Risks
Despite the ongoing sinking, Kansai Airport is not expected to become unusable in the near future. Current projections suggest that the sinking will continue to decelerate, but climate change poses additional risks. The airport is located in a region vulnerable to storm surges, typhoons, and earthquakes, as evidenced by the severe flooding caused by Typhoon Jebi in 2018.
Engineers predict that certain sections of the airport could be below sea level by 2056 if current trends continue. However, the airport’s management is optimistic, planning expansions to increase capacity to 40 million passengers annually.
Conclusion
Kansai International Airport remains a critical asset for Japan’s aviation sector, despite its sinking predicament. The ongoing investments in infrastructure and adaptation strategies are essential to ensure its operational viability for decades to come. As the airport navigates these challenges, it serves as a reminder of the delicate balance between human ingenuity and the forces of nature.