Latest news with #OsakaBay
The Independent
23-06-2025
- The Independent
Why the world's best airport for luggage handling is sinking into the sea
The Kansai international airport, built on a pair of manmade islands in Japan's Osaka Bay, was once celebrated as a marvel of engineering. Now it's sinking into the sea. The airport is grappling with subsidence problems because it is built on soft clay that cannot adequately support its immense weight. This ongoing sinking threatens the airport's future, as rising seas and natural forces slowly pull down the engineering wonder closer to the depths. The Japanese airport was hailed as a landmark solution to overcrowding – it was meant to alleviate congestion at the nearby Osaka airport – and a model of regional economic competition when it opened in 1994. It was originally estimated to sink 13 feet in 50 years but has outpaced that prediction by going down over 42 feet since construction. '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,' Yukako Handa, former communications director for Kansai Airports, which managed the artificial islands as well as the original Osaka Itami airport on the mainland, told Smithsonian magazine in 2018. He said engineers were astonished by the discrepancy between laboratory predictions of soil consolidation – the process whereby newly added soil layers solidify into a stable base – and the much faster settling that occurred after thousands of tons of fill were deposited into the bay. Last year, the Kansai airport recorded 169,774 flight arrivals and departures and handled 25.9 million passengers, just shy of the pre-pandemic peak of 29.4 million. It was recognised as the world's best airport for luggage handling, according to The Straits Times, maintaining its record of no lost luggage for over a decade. The Kansai airport was conceived as a solution to overcrowding at the Osaka international airport, which was hemmed in by dense urban development. Finding no room for expansion on land, planners opted for an ambitious offshore site in the Osaka Bay, far enough to avoid disturbing local communities, yet close enough to serve the region effectively. This entailed pulling off the engineering feat of building artificial islands on a seabed over 60 feet deep, with Japan 's seismic risks in mind. The runways were specifically designed to flex during earthquakes, reducing the risk of cracks and structural damage. The project cost around £14bn. The airport was constructed atop a seabed composed of soft alluvial clay, which engineers knew would compress under the immense weight of the artificial islands. To accelerate and control this expected sinking, they installed sand drains. However, the subsidence proved far more severe than anticipated. By 1990, just three years into construction, the site had already sunk 27 feet, far surpassing the projection of 19 feet. Despite efforts to manage the sinking with advanced techniques like sand drains, the forces beneath the surface proved too powerful and unpredictable. This dramatic early subsidence revealed just how fragile the airport's foundation truly was. At its core, the Kansai airport's ongoing sinking stems from the very nature of its foundation: soft, loose clay and silt beneath the seabed that naturally compresses under immense weight. The enormous landfill used to create the artificial islands put relentless pressure on this unstable ground, and construction moved forward before the sediment had fully settled, setting the stage for continuous and unavoidable subsidence. To reduce the airport's rapid sinking, engineers invested around £112m to reinforce and raise the seawall around it. They also installed 2.2 million vertical sand-filled pipes deep into the clay seabed to help drain excess moisture and stabilise the ground. These efforts slowed the rate of subsidence. In 1994, the airport was sinking more than 19 inches a year, but by 2008 that had dropped to 2.8 inches. By 2023, the sinking was down to 2.3 inches annually. Despite this progress, the airport remains at risk. Engineers warn that parts of the airport may fall below sea level by 2056 if subsidence continues. Climate change adds another layer of risk to the airport, already vulnerable to storm surges and seismic activity. In 2018, Typhoon Jebi underlined these dangers when it struck Osaka Bay, flooding the runway and forcing a two-week shutdown. High seas flooded one of its two runways, while strong winds sent a 2,500-tonne tanker slamming into the side of a bridge connecting the airport to the mainland. Some 5,000 passengers stranded at the airport were transported to the mainland by boat, according to the daily Japan Times. In response, authorities raised the seawall around the airport by an additional 2.7m to better withstand future flooding. While such engineering solutions implemented over the years have bought precious time, the battle against subsidence and rising seas is far from over for the airport. The bleak prediction from experts has sparked anger among some members of the Japanese engineering community. 'It's irresponsible,' Professor Yoichi Watabe from Hokkaido University's engineering faculty told The New York Times in 2018. Prof Watabe, who has studied the Kansai airport's issues extensively, however did acknowledge that the forecast wasn't completely without merit. Still, he pointed out that the predictions assumed Japan 'will simply stand by and watch it sink without taking action'. He added: 'We definitely will not.'
South China Morning Post
16-06-2025
- South China Morning Post
Japan's sinking airport: how much lower can Kansai International go?
Japan 's Kansai International Airport (KIX) has won international awards for its architectural design, efficiency and staff, and was recognised last year as the best airport in the world for baggage delivery after not mislaying a single item of luggage for a decade. Despite all the plaudits, KIX has a major drawback: it is sinking. Built on a man-made island in Osaka Bay, KIX was one of the largest construction and engineering projects ever undertaken in Japan. Made up of two islands, one covering 510 hectares (1,260 acres) and the second over 1,055 hectares, it was built to ease overcrowding at the nearby Osaka International Airport and welcomed its first passenger flight in September 1994. Since then, it has grown into a major hub for both domestic and international flights, with around 30.6 million passengers linked to 91 cities in 25 countries in 2024. While the numbers are impressive, it is hard to get past the fact that the airport has already sunk into the clay layers beneath the bay more than engineers initially expected, and it continues to inch lower every year. According to operator Kansai Airports, the surface of the airport's first island is today about 3.84 metres (12.6 feet) lower than when it opened in 1994. Since landfill began for its construction, the airport has experienced an average settlement of 13.66 metres (45 inches). The operator is keen to point out that some 'settling' of the surface level was always expected. The average subsidence measured just 6cm (2.4 inches) across 17 points on the artificial island last year, according to the latest data released in December.
CTV News
09-06-2025
- Health
- CTV News
Japan's Osaka Expo temporarily suspends water shows after high levels of bacteria detected
A view of 'Water Plaza' at the site of the World Exposition in Osaka, on June 4, 2025.(Atsuhiro Maeda/Kyodo News via AP) TOKYO — Popular daily fountain shows and a shallow pool area at Expo 2025 in Osaka have been temporarily suspended due to bacterial contamination that required cleaning and safety checks, the event organizers said on Monday. The aquatic show at the Water Plaza has been suspended since June 4 when legionella bacteria of up to 20 times the legal limit was detected in the water, a week after lower levels of contamination had been found. Another water area, called the Forest of Tranquility — a shallow reservoir over 2.3 hectares (5.7 acres) where visitors can soak their feet and relax — has also been closed for cleaning due to the legionella contamination, which can cause pneumonia. The bacteria contamination is the latest problem hitting the Expo site, where swarms of midges have been bothering visitors for weeks. The venue, built on a former industrial waste burial site in the Osaka Bay in western Japan, where methane gas was detected days before the opening in April. The use of insecticides have so far not effectively blocked the midges. Organizers say they now believe the source of the midges is the Water Plaza and that additional measures are under way, such as installing an insect screen. Organizers have also taken anti-bacterial measures at the water areas, including increased sanitation, cleaning drainage pipes and increasing water circulation, to improve water quality at the reservoir and get approval for a reopening from the health authorities. Hiroyuki Ishige, secretary general of the Japan Association for the 2025 World Exposition, said the organizers should have acted more quickly to close down the water area after detecting increased levels of contamination. 'We deeply apologize over the inconveniences we have caused to the visitors who were looking forward to the (water) shows,' Ishige told a media briefing on Monday. Organizers says there has been no reported health issues. The Osaka Expo involves participants from more than 160 countries, regions and organizations who are showcasing their futuristic exhibits. Organizers had expected 28 million visitors through mid-October. Mari Yamaguchi, The Associated Press
The Independent
09-06-2025
- Health
- The Independent
Japan's Osaka Expo temporarily suspends water shows after high levels of bacteria detected
Popular daily fountain shows and a shallow pool area at Expo 2025 in Osaka have been temporarily suspended due to bacterial contamination that required cleaning and safety checks, the event organisers said on Monday. The aquatic show at the Water Plaza has been suspended since June 4 when legionella bacteria of up to 20 times the legal limit was detected in the water, a week after lower levels of contamination had been found. Another water area, called the Forest of Tranquility — a shallow reservoir over 2.3 hectares (5.7 acres) where visitors can soak their feet and relax — has also been closed for cleaning due to the legionella contamination, which can cause pneumonia. The bacteria contamination is the latest problem hitting the Expo site, where swarms of midges have been bothering visitors for weeks. The venue, built on a former industrial waste burial site in the Osaka Bay in western Japan, where methane gas was detected days before the opening in April. The use of insecticides have so far not effectively blocked the midges. Organizers say they now believe the source of the midges is the Water Plaza and that additional measures are under way, such as installing an insect screen. Organizers have also taken anti-bacterial measures at the water areas, including increased sanitation, cleaning drainage pipes and increasing water circulation, to improve water quality at the reservoir and get approval for a reopening from the health authorities. Hiroyuki Ishige, secretary general of the Japan Association for the 2025 World Exposition, said the organizers should have acted more quickly to close down the water area after detecting increased levels of contamination. 'We deeply apologize over the inconveniences we have caused to the visitors who were looking forward to the (water) shows,' Ishige told a media briefing on Monday. Organizers says there has been no reported health issues. The Osaka Expo involves participants from more than 160 countries, regions and organizations who are showcasing their futuristic exhibits. Organizers had expected 28 million visitors through mid-October.
Yahoo
06-06-2025
- Yahoo
Bacteria cancels water shows at Japan's World Expo
The discovery of high levels of bacteria has led the World Expo in Japan's Osaka to suspend daily water shows and use of a shallow play pool, organisers said. It comes after visitors also complained that swarms of tiny flying insects had invaded the vast waterfront site where Expo 2025 runs until mid-October. Nearly six million people have visited exhibits from more than 160 countries, regions and organisations since it opened in April. Although polls showed that public enthusiasm for the Expo was lukewarm before its opening, organisers say crowds have been growing, especially in recent weeks. But concerns were raised over environmental conditions at the reclaimed island site in Osaka Bay, which was once a landfill. Organisers said Thursday that high levels of legionella bacteria had forced them to close an area with shallow water where visitors, including children, could cool off. That followed a statement released Wednesday saying daily fountain shows with music and lights at an artificial pond had been suspended for the same reason. They said they were cleaning the affected areas, adding that a decision would come on Friday on whether the shows could resume. Days before the Expo opened, a level of methane gas high enough to potentially ignite a fire was detected at the site. More recently, organisers sprayed insecticide to deter swarms of non-biting midges bothering guests. Also known as a World's Fair, the Expo phenomenon, which brought the Eiffel Tower to Paris, began with London's 1851 Crystal Palace exhibition. It is now held every five years in different global locations. hih/kaf/fox
