22nd February 2025 – (Tokyo) The recent 4.6-magnitude earthquake that struck the eastern region of Yamanashi Prefecture on the evening of 20th February this year has reignited concerns about the potential for a catastrophic eruption of Mount Fuji, Japan’s iconic and dormant volcanic peak. While the Japan Meteorological Agency has not issued any warnings suggesting an imminent eruption, the quake’s proximity to the Fuji Five Lakes area, just 20 kilometres from the volcano’s summit, has sparked widespread discussions and anxieties among the public.
The Hoei eruption, which occurred during the Edo period, remains etched in Japanese historical memory as a testament to the destructive force of nature. For two weeks, volcanic ash rained down upon what is now the bustling metropolis of Tokyo, blanketing the city in a thick, choking shroud. The impact of a similar event in the present day would be nothing short of apocalyptic.
According to internal government data on eruption countermeasures, a Hoei-like eruption could potentially cut off supply lines to approximately 60% of the 44.33 million residents of the Tokyo metropolitan area within two weeks. The consequences would be far-reaching and devastating, with an estimated 27 million people left without electricity and a staggering 26.7 million individuals forced to evacuate as the weight of the ashfall threatens to collapse even wooden houses.
Professor Emeritus Toshitsugu Fujii, who served as the chief of a government working group on ashfall countermeasures, highlights the gravity of the situation: “Three centuries have passed since the Hoei eruption, and it is possible that magma is accumulating. So, there is no surprise that it could erupt at any time.”
Tokyo, the beating heart of Japan and a global economic powerhouse, would find itself in the crosshairs of this volcanic onslaught. The government’s Central Disaster Prevention Council has estimated that a violent eruption could blanket parts of the metropolitan area with up to 10 centimeters of ash, crippling transportation networks and disrupting vital infrastructure.
Overground trains, the lifeblood of Tokyo’s intricate transit system, would grind to a halt as ash accumulates on railway tracks across seven prefectures, including Tokyo, Ibaraki, Saitama, Chiba, Kanagawa, Yamanashi, and Shizuoka. Even the city’s extensive subway network would be rendered inoperable, as power outages caused by ash adhering to transmission facilities bring the underground arteries to a standstill.
The impact on logistics and supply chains would be catastrophic, creating vast swaths of the city where residents would struggle to obtain essential supplies, exacerbating the already dire situation. Communication failures could further compound the crisis, as ash clinging to the antennas of base stations threatens to sever vital lines of information and coordination.
Water, a fundamental necessity for life, could become a scarce commodity as volcanic ash contaminates and clogs water treatment facilities, rendering tap water undrinkable or even causing outages. The weight of the ash, made heavier by rainfall, could even cause the collapse of aging wooden structures, adding to the potential for loss of life and property damage.
In the aftermath of such a cataclysmic event, Tokyo would be faced with the daunting task of disposing of nearly 500 million cubic meters of volcanic ash – a staggering amount roughly ten times the volume of disaster waste generated by the Great East Japan Earthquake of 2011.
The paralysis of transportation and logistics, coupled with the disruption of essential services and the potential for widespread structural damage, would undoubtedly have ripple effects extending far beyond the confines of the Tokyo metropolitan area, reverberating throughout Japan and potentially impacting global markets and supply chains.
As the nation grapples with the looming threat of a Nankai Trough megaquake, which experts have warned has an 80% probability of occurring within the next 30 years, the spectre of a simultaneous volcanic eruption could prove to be a devastating one-two punch for Japan’s resilience and preparedness
AloJapan.com