The damage from a deadly large-scale mudslide that occurred in the central Japan city of Atami in Shizuoka Prefecture on July 3 may have been exacerbated by an embankment at the top of the mountain, it has emerged.
Shizuoka Gov. Heita Kawakatsu said at a press conference that his government intends to fully look into the matter: "Almost the entire embankment went down with the mudslide. We will thoroughly investigate just who piled up this soil, and for what purpose."
Embankments are manmade structures comprising hardened soil. According to Shizuoka Prefectural Government estimates, of the around 100,000 cubic meters of material that came down in the mudslide, soil from the embankment is thought to represent about 54,000 cubic meters of it. It appears the embankments were constructed in 2010 or earlier.
It is expected that experts will go ahead with investigations, but Hirofumi Ota, head of the prefectural government's crisis management department, spoke reservedly on July 6: "We are keeping in mind that the unambiguous cause of this was destructive, irregular weather conditions. Even if there was a development, making assumptions including that private-sector projects are one of the causes could lead to individuals being targeted for defamation."
Regarding the embankment, workers and others have been sighted disposing of excess soil in the area around it before the disaster, and nearby residents had also voiced their concern over its existence. At a July 6 press conference, Atami Mayor Sakae Saito only went as far as saying: "The establishment of a causal relationship is dependent on investigations by experts."
In response to this mudslide disaster, the Ministry of Land, Infrastructure, Transport and Tourism has decided to inspect embankments nationwide for safety. Jurisdiction over embankments is covered by a number of state ministries and agencies, and the land ministry intends to partner with its counterparts including the Ministry of Agriculture, Forestry and Fisheries and the Ministry of the Environment to carry out the survey.
Because of assertions that the embankment increased the damage in this latest case, the land ministry decided it is necessary to hold investigations as to whether similar sites exist across the country. Specific methods will be decided at a later date.
At a July 6 press conference, Minister of Land, Infrastructure, Transport and Tourism Kazuyoshi Akaba said, "We are aware that we must consider moving toward comprehensive checks of embankments across the country, in tandem with ministries and agencies concerned."
(Japanese original by Hideyuki Yamada, Shizuoka Bureau, and Kunihiro Iwasaki, Tokyo City News Department)