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2020 July 1 - 7 TOP3 [POLITICS]

Experts: Planned seawalls for new base in Henoko will probably collapse even with weak quake

A group of geological experts on July 1 published the results of its analysis indicating that seawalls to be built for a new U.S. base in Okinawa’s Henoko district will most likely collapse even with a weak earthquake.

The expert team since 2019 has conducted investigations into technical problems regarding the Henoko base project, including an extremely soft seafloor and the existence of active faults under the construction site. Niigata University Professor Emeritus Tateishi Masaaki, who heads the team, said, “It is totally reckless of the government to ignore these problems and push forward with the U.S. base construction in Henoko. The Defense Ministry should carry out an analysis and publish the findings.”

According to the geological experts, at an observation point near the construction site in Henoko, between 2010 and 2020, earthquakes categorized as level 1 or stronger under the Japanese seismic intensity scale were recorded 60 times. Of them, 13 quakes registered 2 or higher and three quakes marked 3 or more on the ten-level Japanese seismic scale. Given this, an earthquake with at least a level 1 intensity will certainly occur while the Henoko reclamation work is being conducted and a level 2 earthquake will most likely occur, the experts believe.

Based on a computer analysis of the planned seawalls in Henoko with the use of software for designing harbor structures, the geologists warn that if hit by a level 1 earthquake after completion, the seawalls in the construction area designated as C-1-1-1 will collapse; a level 2 earthquake will cause the seawalls in all areas but the C-2 construction area to collapse and a level 3 quake during the construction will result in the collapse of the unfinished seawalls in the C-1-1-1 area.

Past related articles:
> US House expresses concern about mayonnaise-like seafloor in Henoko [June 26 & 27, 2020]
> Geologists: Active faults may be beneath US base construction site at Henoko [March 5, 2019]