A major eruption of Mount Fuji would displace 470,000 people due to ashfall while up to 238,000 residents at the foot of Japan’s tallest peak would be forced to flee from lava, officials warned.
The Yamanashi, Shizuoka and Kanagawa prefectural governments drew up an evacuation plan for a possible Mount Fuji eruption similar in scale to its last major eruption in 1707. The central government and other parties were also involved in charting the plan, which was released Feb. 6.
The contingency plan covers the three prefectures nearest to the 3,776-meter mountain.
“We also need to forecast damage for the entire Tokyo metropolitan area,” Toshitsugu Fujii, a member of the commission that compiled the plan and chairman of the central government’s coordinating committee for prediction of volcanic eruptions, told a news conference.
The evacuation plan also does not discuss how to deal with tourists to the popular World Heritage site.
According to the plan, an eruption comparable to the 1707 Hoei eruption would blanket a large area covering Tokyo and Chiba, Saitama, Kanagawa, Yamanashi and Shizuoka prefectures with 2 centimeters or more of ash, which could affect human health.
Large cities such as Tokyo, Yokohama and Kawasaki would be among those affected.
In areas with an ashfall of 30 cm or more, wooden housing could collapse if it rains. A total of 470,000 residents in the three prefectures would have to evacuate to sturdier buildings or outside their communities. Nearly 90 percent, or 406,000, would be in Kanagawa Prefecture.
Fourteen municipalities in Shizuoka and Yamanashi prefectures, home to 750,000 people, could be affected by lava flows, depending on the direction of the molten rock.
The plan specified 17 areas along major ridges of the volcano where lava flows are expected, and determined when and where residents would have to evacuate based on the Japan Meteorological Agency’s eruption warning levels.
Up to 238,000 residents would have to evacuate if the lava flows to Shizuoka Prefecture, while 84,000 would be displaced if it heads toward Yamanashi Prefecture.
A Mount Fuji eruption could also cause major disruptions in transportation, utilities and other public infrastructure.
According to a report compiled by a central government expert panel, roads would be rendered unusable with a daily ashfall of 5 cm under dry conditions and even 5 millimeters under rainy conditions.
An adverse impact is also expected on train rail wheels, airport runways and aircraft engines. Closures of transportation arteries such as the Tomei Expressway, the Tokaido Shinkansen Line and Haneda Airport would paralyze the flow of people and goods across the country.
Experts also say gas turbines at thermal power plants would stall if ash clogs anti-dust filters, and power lines could be shorted out by wet ash.
In a past eruption of Sakurajima in Kagoshima Prefecture, power went out in areas with an ashfall of 1 cm or more.
There are concerns that a similar situation could lead to a disaster of national proportions in the Tokyo metropolitan area, where central government ministries and corporate head offices are concentrated.
sumber: asahi.com