Japanese Govt to Revise Nankai Trough Quake Guidelines to Prevent Confusion

Yomiuri Shimbun

3 days ago

The government intends to revise the guidelines that state what actions to be taken by residents, companies and others when a Nankai Trough Earthquake Extra Information advisory is issued.
The move to expand the contents of the guidelines was made considering the confusion over how to respond in various regions when the advisory was issued for the first time in August of last year. The Cabinet Office will launch a committee of experts from relevant fields soon, aiming to revise the guidelines as early as next month.
The Nankai Trough Earthquake Extra Information advisory with the key word Megathrust Earthquake Attention is issued when an earthquake between a magnitude 7.0 and magnitude 8.0 is considered to have occurred in the probable source region of the Nankai Trough. An advisory with the key word Megathrust Earthquake Alert is issued when a quake with a magnitude 8.0 or higher is considered to have occurred.
The guidelines were created to coincide with the launch of the Extra Information advisory system in May 2019. However, they focus on actions to be taken by residents and companies when an advisory with the key word Megathrust Earthquake Alert is issued, and it mentions little for the case of one with the phrase Megathrust Earthquake Attention.
The lack of explanation for an Earthquake Attention advisory led to areas taking different responses on things such as whether to open evacuation centers or cancel previously planned events when such an advisory was issued last August. The local governments of the region where the advisory was released have since called for the central government to compile the guidance of standardized responses.
When revising the guidelines, the government intends to create a new section for local governments that show which measures are to be taken, in addition to the existing sections for residents and companies. Each section will have a list of responses in the event of an Earthquake Attention advisory being issued.
With this revision, the government hopes to ensure that local governments can take measures in accordance with the local situation while maintaining the balance between safety and social activities. Such measures cover securing evacuation places, providing necessary information to residents, holding scheduled events and the operations of schools.
The content regarding the Earthquake Alert advisory will also be expanded. One such example includes advising municipalities to designate areas below sea level subject to evacuation in advance for a week when it is issued. The area below sea level has potential risk of flooding if the embankment is destroyed by a powerful earthquake.