The hazard map, which spans Shizuoka and Yamanashi prefectures and assumes the eruption of Mt. Fuji, which is visited by many climbers every year, has been revised for the first time in 17 years.


It was estimated that the amount of lava flowing out from a large-scale eruption would be about double that of the past, and could extend to areas more than tens of kilometers away, such as Uenohara City and Sagamihara City in Yamanashi Prefecture.


The council will revise the wide area evacuation plan based on the map.

The "Mt. Fuji Volcano Disaster Prevention Measures Council" created by the three prefectures of Shizuoka, Yamanashi, and Kanagawa and the national government created a new hazard map based on the latest survey results and the results of examinations based on topographical data, and on the 26th. I reported at the meeting.



According to this, the range of the assumed crater will expand to the southwest, and the amount of lava that will flow out in the event of a large-scale eruption will reach 1.3 billion cubic meters, which is about twice as much as before.



As a result, the range in which lava flows down is wider than expected in the past, not only in local governments around the mountaintop such as Fujiyoshida City in Yamanashi Prefecture and Gotemba City in Shizuoka Prefecture, but also in Uenohara City and Sagamihara City in Yamanashi Prefecture, which are more than 40 km northeast. , Odawara City, Kanagawa Prefecture on the southeast side, Shizuoka City Shimizu Ward on the south side, and 7 cities and 5 towns in 3 prefectures.



In addition, the case where lava reaches the JR Chuo Main Line and the Chuo Expressway was also considered.



It can also have a significant impact on the movement of people and logistics.



In addition, in some areas of the foothills, lava flows are expected to take less time to reach the city.



In addition, the amount of pyroclastic flow ejected is estimated to be 10 million cubic meters, which is more than four times as much as before, and the reach on the northeastern and southwestern sides is estimated to be about 2 to 4 kilometers longer than previously expected.



In this report, the results of studies on the "snowmelt-type lahar" where the accumulated volcanic ash erupts and melts the snow and flows down as a mud flow, and the reach of large volcanic stones are also shown.



Regarding the assumption of the eruption of Mt. Fuji, last year, a national study group released a simulation when volcanic ash concentrated in the metropolitan area, but the hazard maps for lava flows and pyroclastic flows have been revised for the first time in 17 years.



"96% of past eruptions are small and medium-sized eruptions, but the next eruption could be a large, infrequent eruption," the report said.



The council will revise the wide-area evacuation plan based on the published map, and each local government will also review the disaster prevention plan.

Governor Kawakatsu of Shizuoka Prefecture "Making an evacuation plan based on correct knowledge"

Governor Kawakatsu of Shizuoka Prefecture, who chairs the council, said that the addition of the assumption that lava flows will spread farther and reach urban areas in a shorter time is "4% of large-scale eruptions in the last 5600 years. Only. I would like to make an evacuation plan based on the correct knowledge that I fear correctly including such numbers. On the other hand, since this is an assumption, I would like to prepare for responding flexibly. " I did.



Regarding the assumption that ash will continue to accumulate over a wide area of ​​the Tokyo metropolitan area, "For example, in Kyushu, we have experience of ash fall due to the eruptive activity of Sakurajima, but in Kanto, we have little experience. The damage of ash fall is expected to be enormous. Therefore, it is important to share cases such as Kagoshima with Shizuoka, Yamanashi, Kanagawa, etc. and prepare for them. "

Kanagawa Prefecture Expected to reach lava flow for the first time

This time, in Kanagawa Prefecture, it was assumed that the lava flow would reach the eruption of Mt. Fuji for the first time.



Seven cities and towns are expected to be newly designated as volcanic disaster warning areas in the future, and Kanagawa Prefecture will proceed with reviewing disaster prevention plans in cooperation with cities and towns.



Yojiro Takemura, director of the Prefectural Disaster Prevention Department, said, "I think there are concerns about the areas that are said to be affected, so first of all, we hold briefing sessions in cooperation with the municipalities and provide accurate information on the damage assumptions. I want to go. "

"Fear of arrival" Yamanashi Uenohara City

In Uenohara City, Yamanashi Prefecture, where new lava flows may arrive, there are voices of confusion about the results of this revision.



Uenohara City is located on the easternmost side of Yamanashi Prefecture, and until now it was said that lava flows would not reach even if Mt. Fuji erupted.



However, depending on the scale of the eruption, the lava flow that flowed along the river could reach the city and reach the JR Chuo Main Line and the Chuo Expressway.



Uenohara City has a hazard map for sediment-related disasters, but not for the eruption of Mt. Fuji.



In addition, Uenohara City was one of the evacuation destinations for residents of Oshino Village, Yamanashi Prefecture, when Mt. Fuji erupted.



However, this time it became necessary to consider their own evacuation destination.



The city wants to prepare stockpiles in preparation for the eruption in the future.



Kyoichiro Watanabe, Deputy Chief of the Crisis Management Office of Uenohara City, said, "I was frankly surprised that I was really here. It may be, and I think that various reviews will be necessary. Protecting the lives and property of the residents is the most important mission, and we have been wondering how we will respond in the future, including disseminating information to the residents. I would like to devise solid measures while listening to the plans and opinions of local governments that have been wary of volcanoes. "

Municipalities that are predicted to reach a new "lava flow"

▽


　Sagamihara City,

Kanagawa Prefecture

Odawara City Minamiashigara City Oi Town Matsuda Town Yamakita Town Kaisei Town


▽ Yamanashi Prefecture


　Otsuki City Uenohara City


▽ Shizuoka Prefecture


　Shizuoka City Shimizu Ward Numazu City Shimizu Town