Osaka Expo temporarily suspends water shows

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 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. Organisers 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.

Organisers 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 organisations who are showcasing their futuristic exhibits. Organisers had expected 28 million visitors through mid-October.

Agencies