The Japanese government announced on Tuesday (01.07.2025) that it has updated its disaster prevention plan aimed at reducing the estimated death toll by about 80% — from a current projection of up to 298,000 — in the event of a massive earthquake hitting the Nankai Trough. The original 2014 disaster preparedness plan also aimed for an 80% reduction in projected fatalities from a strong quake around the seismic zone stretching from western to central Japan. However, officials have admitted that measures taken so far may only reduce casualties by about 20%.
The revised plan by the Central Disaster Management Council emphasizes actions needed over the next decade to accelerate earthquake readiness in designated areas, including dike installations and investments by national and local governments to strengthen infrastructure resilience. The goal of halving the number of buildings potentially destroyed by the quake or subsequent fires — currently estimated at 235,000 — remains unchanged.
Sixteen additional municipalities across six prefectures have been added to the designated disaster prevention zone, bringing the total to 723 towns. The government also aims for all municipalities to conduct regular evacuation drills by the 2030 fiscal year in areas likely to experience large tsunamis. It will seek expert opinions and carry out annual inspections to ensure targeted preventive measures are being implemented.
The plan also proposes tsunami countermeasures for petrochemical complexes and encourages individuals and the private sector to take precautions, such as securing furniture. “A Nankai Trough earthquake appears more imminent compared to when the previous plan was drawn up and could even occur while measures are still being applied,” said Norio Maki, a professor at Kyoto University’s Institute for Disaster Prevention Research.
The government’s deadliest scenario involves a magnitude 9 Richter earthquake occurring on a winter night, with the central Japanese region of Shizuoka expected to suffer the highest death toll, exceeding 100,000.
Nankai Trough is considered one of the most dangerous fault lines on Earth, experiencing mega-quakes every 100 to 200 years. The last major quake struck in 1946. With information overflowing on social media today, rumors are rampant. A popular manga re-released in 2021 predicts a biblical-scale disaster on July 5, 2025 — fueling panic.
It’s no coincidence that foreign tourists are avoiding Japan: flights are being canceled, and arrivals from Hong Kong have dropped by 11% within a month. Some travelers refer to an ‘invisible threat’ looming over the islands.
The ghost of Fukushima continues to haunt the nation. The 2011 magnitude 8.9 earthquake triggered 48-meter tsunamis, killed 15,500 people, caused nuclear meltdowns in Fukushima, and contaminated entire regions with toxic waste. Experts warn that the next mega-earthquake could surpass even that nightmare.
“No one can say exactly when it will happen,” says Riouichi Nomura of the Japan Meteorological Agency (JMA). “But we must prepare — and avoid unnecessary panic. If we don’t, the cost will be incalculable.”