2025 Expo Osaka: High Levels of Legionella Bacteria Detected at Water Plaza; Fountain Shows Cancelled on Thursday and Friday

The Yomiuri Shimbun

13:48 JST, June 5, 2025

OSAKA – The Japan Association for the 2025 World Exposition announced Wednesday that Legionella bacteria had been detected at very high levels in the Water Plaza, a water feature at the Osaka-Kansai Expo site. The association has decided to cancel the fountain shows scheduled for Thursday and Friday.

According to the announcement, the bacteria were detected during a routine inspection conducted by the Osaka city health center on May 26. The association conducted another water quality inspection after cleaning the pipes and taking other measures starting on Saturday, but on Wednesday night they were detected again, at 20 times ordinary levels.

The association decided to cancel the fountain shows after receiving advice from the health center.

The association has stated that it is not in a position to evaluate the impact on human health. No one has complained of health problems at this stage, it said.