Tsunami inundation assumption at the time of a huge earthquake Local governments review disaster prevention plans one after another

Tsunami inundation assumption at the time of a huge earthquake Local governments review disaster prevention plans one after another October 15, 5:05

According to the assumption of a tsunami in the event of a huge earthquake in the "Kuril Trench" and "Japan Trench" announced by the national study group, it has been shown that the government buildings of 38 local governments nationwide may be flooded. According to NHK's interview, nearly half of them are deciding facilities to replace the government building and reviewing evacuation plans in case of a disaster.

Following the Great East Japan Earthquake, the national study group reported on the earthquakes that occur along the "Kuril Trench" from the Kuril Islands to the offshore of Hokkaido and in the "Japan Trench" from the south of Hokkaido to the offshore of Iwate Prefecture. We examined the assumptions of the largest earthquakes and tsunamis, and announced in April this year for areas other than Iwate Prefecture and last month for Iwate Prefecture.

According to it, it was shown that the government buildings of 38 local governments from Hokkaido to Ibaraki prefecture could be flooded by the tsunami and the center of the city could be damaged.

When NHK interviewed these 38 local governments, it was found that nine local governments, including Aomori Prefecture and Kamaishi City, Iwate Prefecture, are considering new designations and changes to alternative government buildings in the event of a disaster.

In addition, in Noboribetsu City, Hokkaido and Kazamaura Village, Aomori Prefecture, it was found that the planned site for the new government building could be flooded, and the plan has to be revised.

Since the central city area may be damaged, the evacuation plans of residents are also affected.

Thirteen local governments, such as Hidaka Town in Hokkaido and Miyako City in Iwate Prefecture, are considering revising their plans, such as changing some evacuation sites.

On the other hand, some local governments have difficulty responding to new assumptions.

At the government building in Samani Town, Hokkaido, which is expected to be flooded at the highest level of 10.6 meters, we are seeking financial support from the government because we cannot relocate the government building or install an alternative government building due to financial resources.

Assuming a tsunami that exceeds the great earthquake, review measures for Kamaishi in the disaster area

In some areas, the municipalities in Iwate Prefecture, which were affected by the Great East Japan Earthquake, have announced that the largest tsunami along the Japan Trench will exceed the disaster, and we will be forced to review the disaster prevention measures that we have taken after the earthquake. I am.

According to the country, it is estimated that the government buildings of five local governments will be flooded in Iwate Prefecture, and four local governments such as Kamaishi City and Kuji City will consider changing or newly designating alternative government buildings.

In addition, since inundation of the central city area is expected, all five local governments are considering reviewing some of the evacuation sites.

In Kamaishi City, where 1064 people were killed in the Great East Japan Earthquake, more than 180 billion yen was invested in the construction of seawalls and the relocation of residential land to higher ground, and the prefecture and city have been promoting reconstruction projects.

In addition, when the city hall was flooded by the tsunami and a large tsunami warning was issued at night or on holidays, we have taken measures such as setting up a disaster response headquarters with the fire department building built inland as an alternative government building.

However, this time, the assumption of a tsunami that exceeds the earthquake has been shown, and there is a risk that the tsunami will inundate the fire department building and even inland residential areas.

In response to this, the city changed the location of the alternative government building and decided to designate the public hall, which is about 5 km from the sea, as the alternative government building.

In addition, Kamaishi City holds briefing sessions for each district in order to convey detailed information to the residents of the newly flooded district.

The city hopes to hold briefings in all districts and then change or add evacuation sites during the year.

Toru Sasaki, Crisis Management Supervisor of Kamaishi City, said, "I would like to make the best use of the lessons learned from the Great East Japan Earthquake and call on the residents to regain their consciousness to evacuate and work to prevent the victims of the tsunami." ..

Review of relocation plan for Aomori Kazamaura Village Office

If a huge earthquake occurs in the "Kuril Trench" and "Japan Trench" from off Hokkaido to off Iwate Prefecture, it was found that the relocation destination of the government office in Kazamaura Village in Aomori Prefecture may be flooded by the tsunami, so the relocation plan I have to review it.

In Kazamaura Village, Aomori Prefecture, which faces the Tsugaru Straits, the government office building was built 84 years ago in 1945, and it is aging. In addition, the prefecture indicated that it would be 1 meter to 2 meters. Since it was said that it would be flooded by about a meter, we are proceeding with a relocation plan from the beginning.

The relocation destination was the site of an elementary school about 6 meters above sea level, and it was planned to relocate at the earliest four years later, but the huge earthquakes of the "Kuril Trench" and "Japan Trench" announced by the national study group in April. Assuming a tsunami caused by the earthquake, it was found that the area around the site of the elementary school could be flooded by about 2 to 5 meters.

For this reason, the village return the plan to the white paper, but looking for a new transfer destination, there is no public land with a size that can build a government office building is on a hill in the village, it is that the prospect of the transfer has not been set.

In addition, the relocation cost of about 2 billion yen will be covered by utilizing the "emergency disaster prevention / mitigation business bond", which the government will substantially bear 70% of the cost when relocating the government office for disaster prevention reasons. However, since the system is said to end in March next year, which is 10 years after the Great East Japan Earthquake, the financial burden on the village is expected to increase even if a relocation destination is found.

Hiroshi Tomioka, the mayor of Kazamaura Village, said, "The announcement of the new tsunami assumption coincided with the spread of the new coronavirus infection, which is a double pain, but we will secure a safe place even if it takes time and proceed with the relocation. I want to go. "

Expert "Development and training of alternative government buildings based on new assumptions"

Professor Emeritus Hiroaki Yoshii of Tokyo Keizai University, who is familiar with the disaster prevention plans of local governments, commented on the local government's response to the new inundation assumption. It will be difficult to do so. It is necessary to prepare for alternative government buildings and conduct training based on new assumptions. "

On the other hand, responding to new assumptions will be a heavy burden for small-scale local governments, so it is necessary to support the national and prefectural governments and promote effective planning.

In addition, Professor Emeritus Yoshii said, "We must not repeat the tragedy that the government building was damaged and many staff members died as in the case of the Great East Japan Earthquake. It is important to make a solid evacuation plan for staff members by reviewing this assumption." He pointed out that it is necessary to take measures not only to deal with the residents but also to protect the lives of the staff.