Photo/Illutration Construction of public housing is under way near the town hall building in Kuroshio, Kochi Prefecture, in December. Kuroshio is ahead of many other local governments in Japan in moving public facilities to elevated ground to prepare for tsunami spawned by a mega-quake. (Tatsuya Chikusa)

Bracing for a tsunami unleashed by the anticipated Nankai Trough mega-quake off Japan's Pacific coast, more than 40 percent of vulnerable municipalities have either relocated or plan to relocate public facilities to higher ground for safety.

A survey by The Asahi Shimbun showed that 62 of 139 cities, towns and villages that are in high-risk areas when the earthquake strikes have already relocated public facilities such as local government offices, fire stations, schools and hospitals, or are planning to do so.

The Nankai Trough is a submarine trench on the Pacific side of the Japanese archipelago stretching from the eastern part of the main island of Honshu to waters east of Kyushu island in southern Japan.

The central government projects a 70-80 percent likelihood that a Nankai Trough mega-quake will strike the region within 30 years.

When the Great East Japan Earthquake and tsunami devastated the northeastern Tohoku region in 2011 many local government buildings were inundated, rendering them impossible to use for command centers to deal with the catastrophe.

That experience has led the central government to recommend the relocation of such buildings in vulnerable areas.

The central government is providing funds for the relocation projects to lessen the financial burden on municipalities.

The Asahi survey, conducted by questionnaire this month, covered the 139 municipalities in Tokyo and 13 other prefectures from Chiba Prefecture to Kagoshima Prefecture, with all municipalities providing responses.

A similar survey in 2015 reported 43 municipalities saying they had relocated or planned to relocate 129 facilities.

The number rose to 62 local governments and 191 facilities, as of December this year.

Compared with the previous survey, 13 more fire stations were moved to higher ground.

The facilities that saw the biggest increase were elementary and junior high schools, surging to 22 from eight.

The survey also found that 77 local governments do not have plans to relocate.

Of the 77, 23 replied that there are no facilities that needed to be relocated, while 17 cited a lack of sufficient funds for relocation.

Eleven said no suitable land exists for relocation within their jurisdiction. Two said they have not gained public support for relocation.