Photo/Illutration A rendering of the Osaka-Kansai Expo 2025 venue (Provided by the Japan Association for the 2025 World Exposition)

Organizers of the Osaka-Kansai Expo 2025 have updated their emergency policies to include detailed evacuation and rescue plans in preparation for earthquakes, typhoons or other natural disasters.

In the event of a major natural disaster, up to 150,000 people could be stranded at the Yumeshima venue, according to plans published on Sept. 2 by the Japan Association for the 2025 World Exposition.

The association anticipates a total of 28.2 million visitors during the six-month event period starting on April 13 of next year, with daily attendance peaking at 220,000 on the busiest days.

There are three access routes to the artificial island in Osaka Bay: roadways across the Yumemai bridge and the Yumesaki tunnel, and Osaka Metro’s Chuo Line—which also runs through the Yumesaki tunnel.

If these routes are cut off, organizers will request municipal and prefectural authorities to send ships to the container ship dock on the eastern side of the island to evacuate visitors. Helicopters will also be deployed for medical emergencies.

If land routes remain open, visitors will be asked to use buses or walk off the island to return home.

Visitors can also take shelter at the expo venue if necessary. Temporary evacuation sites will be set up in the pavilions, beneath the large ring-shaped wooden roof—the symbol of the expo—and other buildings.

For this situation, emergency supplies for three days will be stocked at the venue, including 600,000 servings of food. Separately, municipal and prefectural governments will have an additional 300,000 meals ready on the island.

Estimates predict that if the long-expected Nankai Trough earthquake struck during the expo, it would register a seismic intensity of lower 6 on the Japanese scale of 7 at the venue.

Such a quake would be expected to trigger a tsunami with a maximum height of 5.4 meters, but organizers believe that the venue, elevated 11 meters above sea level, would be safe.

However, they predict that the earthquake would destroy the routes to and from the island, stranding a massive amount of visitors.

In the event of an approaching typhoon, organizers will decide a couple of days beforehand whether to close the venue or shorten opening hours.

To simulate potential responses, organizers have studied past typhoon disasters, including the one that hit Kansai International Airport in 2018, another artificial island in Osaka Bay.

If there is a risk of lightning, visitors will be urged to evacuate from the upper part of the large roof ring and the grove of 1,500 trees at the center of the ring.

To ensure these plans function as intended, disaster drills will be conducted repeatedly until the event’s opening.

(This article was written by Shinji Hakotani and Tatsuya Harada.)

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