The Japanese government announced on Tuesday (July 1, 2025) that it has updated its disaster preparedness plan for a potential megaquake along the Nankai Trough, aiming to reduce the estimated death toll by about 80%—from up to 298,000 people. The original 2014 earthquake preparedness strategy also targeted an 80% reduction in projected fatalities from a powerful quake near the seismic zone stretching from western to central Japan. However, officials admitted that measures taken since then have only reduced casualties by approximately 20%.
The revised plan, released by the Central Disaster Management Council, emphasizes actions to be implemented over the next decade to accelerate seismic readiness in designated areas. These include dike installations and investments by both national and local governments to reinforce infrastructure resilience. The goal of halving the number of buildings potentially destroyed by the quake or subsequent fires—from the current estimate of 235,000—remains unchanged.
In addition, 16 new municipalities across six prefectures have been added to the designated disaster prevention zone, bringing the total to 723 towns. Authorities aim to ensure all municipalities conduct regular evacuation drills by fiscal year 2030 in tsunami-prone regions. Expert consultations and annual inspections will also be carried out to monitor the implementation of preventive measures.
The plan further proposes tsunami countermeasures for petrochemical complexes and encourages individuals and businesses to take precautions such as furniture anchoring. ‘A Nankai Trough earthquake appears more imminent compared to when the previous plan was formulated and could even occur while these measures are being implemented,’ warned Kyoto University professor Norio Maki.
The government’s worst-case scenario envisions a magnitude 9.0 Richter earthquake striking on a winter night, with Shizuoka Prefecture expected to suffer the highest death toll—over 100,000 lives. The Nankai Trough is among the world’s most dangerous fault lines, experiencing catastrophic quakes every 100 to 200 years—the last being in 1946.
With social media amplifying rumors and a popular manga predicting biblical destruction on July 5, 2025, panic is rising. It’s no coincidence that foreign tourists are avoiding Japan—flights are being canceled, and arrivals from Hong Kong dropped 11% within a month. Some travelers refer to an ‘invisible threat’ looming over the islands.
The ghost of Fukushima still haunts the country. The 2011 magnitude 8.9 quake triggered 48-meter-high tsunamis, killed 15,500 people, melted nuclear reactors in Fukushima, and contaminated entire regions with toxic waste. Experts warn that the next megaquake could surpass even that nightmare. ‘No one can say exactly when it will happen,’ says Ryōichi Nomura of the Japan Meteorological Agency. ‘But we must prepare—and avoid unnecessary panic. If we don’t, the cost will be incalculable.’