Megaquake Alert: 520,000 Evacuate Order Issued
Japan Prepares for Potential Megaquake: Over 520,000 Face Evacuation Orders
Table of Contents
Published August 20, 2024, 19:06 JST
Overview
More than 520,000 residents in Japan could be urged to evacuate for up to a week if a megaquake alert is issued for the nankai trough, a seismically active zone off the country’s Pacific coast. This figure, revealed in a recent government survey, surpasses the number of evacuees following the devastating 2011 Great East Japan Earthquake adn Fukushima nuclear disaster (approximately 470,000).
The Threat: Nankai Trough and Tsunami Risk
The Nankai Trough is capable of generating earthquakes with magnitudes exceeding 8.0. A major rupture along this fault line is expected to trigger a large tsunami that could reach coastal communities within minutes, leaving little time for traditional evacuation procedures. This necessitates pre-emptive evacuation plans,notably for vulnerable populations.
The government is actively working with municipalities to identify and designate “advance evacuation areas.” these areas are categorized based on resident needs: those requiring full evacuation and those prioritizing the elderly and individuals with mobility challenges.
survey Findings: Regional Breakdown
The survey, conducted by the Cabinet Office between June and August, encompassed 707 municipalities across 29 prefectures designated for disaster preparedness as of May. 103 municipalities in 16 prefectures have already designated advance evacuation zones.
| Prefecture | Residents for Advance Evacuation |
|---|---|
| Kochi | 92,100 |
| Miyazaki | 79,900 |
| Shizuoka | 70,200 |
| Total (across 16 prefectures) | 520,000+ |
Specifically, 245,600 residents are in areas requiring complete evacuation, while 274,800 are in areas focused on assisting those needing more time to relocate.
The Alert System: Advisory vs. Alert
In 2019, Japan implemented a two-tiered emergency data system for the Nankai Trough megaquake: a “megaquake alert” (requiring immediate advance evacuation) and a “megaquake advisory” (providing information but not mandating evacuation).
The system was first tested in August 2023 with the issuance of a megaquake advisory. This initial deployment caused some unintended consequences, including beach closures and hotel booking cancellations, highlighting the need for clear public interaction and understanding of the alert levels.