Photo/Illutration A Cabinet Office report released on Dec. 21 said the Yufutsu district of Tomakomai, Hokkaido, home to many large industrial plants, would be entirely submerged in a tsunami generated by an earthquake hitting along the Japan Trench east of northern Japan. (Asahi Shimbun file photo)

Up to 199,000 people would be killed by a devastating tsunami if a maximum-scale earthquake strikes off the Pacific coast from Hokkaido to the northern part of the Tohoku region, according to recently released government estimates.

Staggering as the figure is, we should prepare ourselves on the understanding that down-to-earth basic precautions can save many lives.

The Great East Japan Earthquake, which triggered a powerful tsunami and the Fukushima nuclear disaster on March 11, 2011, has led to a review of the scale estimates of potential earthquakes to prevent a repeat of an “unanticipated” disaster.

Geological studies have shown that major tsunami have recurred in the areas in question once in 300 to 400 years.

The risk of another giant quake and tsunami was evaluated as “imminent” because the last ones occurred in the 17th century.

The government report said a magnitude-9 class earthquake would send tsunami waves with a maximum height of nearly 30 meters to coastal areas of Hokkaido and the northern Tohoku region.

The death toll, mostly from the tsunami, was estimated at between 6,000 and 199,000 for a quake hitting along the Japan Trench east of northern Japan, and between 22,000 and 100,000 for a temblor striking along the Chishima (Kuril) Trench east of Hokkaido.

The estimates carry wide ranges because the extent of damage could vary wildly depending on the time of the year and the time of the day.

Under the worst-case scenarios, a quake and tsunami would occur in the dead of night in winter.

Survivors of such a disaster would have to put on cold weather clothing and flee along roads already made dangerous by snow and ice. The ground would continue shaking for a long time, including from aftershocks.

Still, simulations released with the report showed that preventive measures could reduce the death toll by around 80 percent.

To achieve such a reduction, local governments would be required to build tsunami evacuation towers, designate tsunami evacuation buildings, seismically retrofit public facilities and take other steps.

They would also have to work out community evacuation plans and timelines for individual residents while organizing a system to support elderly and other vulnerable citizens.

The government and the Diet should create a system to provide financial assistance for these projects, including setting aside necessary budgets. And they could consider revising relevant laws and regulations.

The government report also said measures should be taken that could prevent up to 42,000 people from dying of hypothermia outdoors after managing to flee from a tsunami.

Authorities should ensure that proper checks and updates are made for stockpiles of cold weather gear and other supplies at evacuation shelters.

The 3/11 disaster showed that a tsunami repeatedly hits the coast with drift articles, such as debris and automobiles.

People cannot hope to stay afloat in a tsunami and wait for rescuers. Their only way to avoid the waves is to live on safe elevated ground or take flight immediately to higher ground.

Residents should ensure they know the evacuation routes and where to take shelter in a disaster. They should also join emergency drills that cover disasters hitting at different times of the year and the day.

A megaquake could strike anywhere on the Japanese islands.

The latest report should prompt all residents of this country to refamiliarize themselves with precautionary measures, such as seismically retrofitting houses, physically securing furniture, preparing emergency survival kits, and confirming how to get in touch with family members in the event of a disaster.

--The Asahi Shimbun, Dec. 29

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