Bacterial Contamination Suspends Water Shows at Osaka's Expo 2025

On April 24, visitors to Osaka's Expo 2025 enjoyed the sunset from the Grand Ring, but recent developments have cast a shadow over the event. The Expo organizers announced on Monday that the enjoyable daily fountain shows and shallow pool areas have been suspended due to the discovery of bacterial contamination requiring extensive cleaning and safety inspections.

Since June 4, the aquatic show at the Water Plaza has been on hold after tests revealed the presence of legionella bacteria at levels as much as 20 times higher than the legal limit. This comes just a week after lower levels of the bacteria were identified, prompting immediate action. Additionally, another area known as the Forest of Tranquility, where guests could relax and soak their feet in a shallow reservoir, has also been closed for necessary cleaning as a result of the legionella findings, which can lead to serious health issues such as pneumonia.

These water-related issues add to a series of challenges faced by the Expo site, which has been plagued by swarms of midges that have inconvenienced visitors for weeks. The venue, situated on a former industrial waste burial ground in Osaka Bay, also experienced methane gas detection shortly before the Expo's opening in April. Attempts to control the midges with insecticides have not yielded satisfactory results, leading organizers to suspect the Water Plaza as the source of the problem. In response, preparations are in motion to install insect screens along with enhanced sanitation measures, such as cleaning drainage systems and boosting water circulation to improve the reservoir’s water quality and obtain necessary health authorities' clearance for reopening.

Hiroyuki Ishige, the secretary general of the Japan Association for the 2025 World Exposition, expressed regret for not acting swiftly to close the water area upon discovering the elevated contamination levels. He publicly apologized for the disruption caused to the visitors who were anticipating the water shows. Despite the contamination issues, the organizers have stated that there have been no reported health incidents linked to these problems. The Expo is expected to attract 28 million visitors from over 160 countries, regions, and organizations, showcasing numerous futuristic exhibits until mid-October.