By: Isuru Parakrama
April 01, World (LNW): The Japanese government has released a sobering report warning that a massive earthquake in the Nankai Trough could result in up to 298,000 deaths, primarily due to tsunamis and building collapses.
The Nankai Trough, a 900-kilometre-long submarine trench off Japan’s Pacific coast, has a history of generating powerful earthquakes. Experts estimate an 80 per cent probability of a magnitude 8 to 9 quake occurring in this region within the next 30 years.
This latest projection marks a slight decrease from the 2012-2013 estimate of 323,000 potential fatalities.
The reduction is attributed to advancements in seismic retrofitting and the development of tsunami evacuation facilities. However, updated terrain and ground data suggest that flooded areas would expand in the event of a tsunami.
Economic repercussions are also expected to be severe, with potential damages estimated at 292.2 trillion yen (approximately $1.81 trillion). This figure represents an increase from the previous estimate of 237.2 trillion yen, reflecting current economic conditions and higher prices.
In a worst-case scenario, the earthquake could trigger tsunamis up to 20 metres high, causing widespread devastation. The timing of such an event could exacerbate its impact; for instance, a winter evening occurrence would pose additional challenges due to colder temperatures and increased indoor activity.
The government report underscores the importance of preparedness and continued investment in disaster mitigation strategies. Whilst improvements have been made since the 2011 Tōhoku earthquake and tsunami, which resulted in over 15,000 deaths and a nuclear disaster, the potential for significant loss of life and economic damage remains a critical concern.
Authorities are urging residents, particularly those in high-risk areas, to familiarise themselves with evacuation routes and to participate in regular disaster drills. The emphasis is on reducing casualties through proactive measures, community awareness, and infrastructure resilience.
References:
https://www.reuters.com/business/environment/japan-estimates-feared-megaquake-could-cause-18-trln-damage-kill-300000-people-2025-03-31/
https://japantoday.com/category/national/up-to-298-000-could-die-in-japan-in-nankai-trough-megaquake-gov%27t
https://www.japantimes.co.jp/news/2025/03/31/japan/japan-nankai-trough-quake-damage-estimate/
https://www.ft.com/content/9528718b-2808-4a09-9198-a65171c6fe65
https://www.the-independent.com/asia/japan/megaquake-japan-warning-when-casualties-damage-b2724411.html
