Japan’s tsunami and nuclear disaster unleashed a $ 300 billion effort to rebuild a hinterland

The country has expanded its reconstruction budget four times in a decade and has released the equivalent of $ 2,400 for each person in Japan to revitalize Tohoku, the northeastern region hit by the tsunami, and to reduce the radiation at the nuclear power plant Reduce. Even as sea walls rise and houses are rebuilt, many people have not returned.

Most of the money was spent rebuilding houses, adding seawalls and repairing other damaged infrastructure with the aim of bringing people back and reviving major industries such as fishing, agriculture and tourism.

Home to about 7% of Japan’s population, the Tohoku region has seen a population decline for over a generation as young people move to larger cities. Half of the tsunami victims were 65 or older.

In the three prefectures most affected by the tsunami, Iwate, Miyagi and Fukushima, the collective population has decreased by 6% since the disaster.

Hundreds of miles of seawalls, some as high as 50 feet (15 meters), have risen along the coast and cost about $ 13 billion. About 80% of the planned 268 miles of seawall has been completed.

In Ishinomaki, waves as high as 10 meters traveled more than 3 miles inland, killing more than 3,000 people, including 74 of the 78 children who attended Okawa Elementary School that day. The city is now protected by sea walls that are as long as 32 feet.

The tsunami crashed over 1,000 miles of the coastline and engulfed some communities up to 6 miles inland. In some cities, houses were extensively destroyed, such as Rikuzentakata in Iwate, where 99.5% of the houses were damaged. In Ishinomaki, 4,000 people died or are still unaccounted for and 76.6% of all houses in the city are at least partially destroyed.

When the earthquake hit, Fukushima Daiichi’s reactors were automatically shut down. Backup diesel generators operated the cooling pumps until two tsunami waves flooded the factory and shut down the generators. In the days that followed, the hydrogen build-up caused explosions in reactors 1, 2 and 3; a fire broke out in 4. Radiation levels reached up to 400 millisieverts per hour (humans are normally exposed to 2.4 millisieverts per year). The government declared an evacuation zone with a radius of 20 kilometers.

Now a forest of steel tanks with more than a million tons of water with radioactive elements grows outside the plant. Water flows through the plant every second and keeps the reactors cool, adding to the problem. The Japanese Government and Tokyo Electric Power Co.

, the owner of the plant, is investigating the release of water containing radioactive tritium in the Pacific Ocean. They say it is safe and other countries are doing the same at their nuclear power plants, but people in fishing are concerned.

Officials estimate that 30 years of work remain before Fukushima Daiichi is completely decommissioned. The biggest task, yet to begin, is to remove molten fuel from reactors 1, 2 and 3. Because the inner parts of the reactors are too radioactive for humans and often inaccessible to robots, they are not yet fully mapped brought or photographed.

Remembrance of what is sometimes called the “triple disaster” – earthquake, tsunami and nuclear meltdowns – is an annual event in Japan. On March 11 this year, the government will hold a ceremony commemorating the 10th anniversary of the disaster at the National Theater in Tokyo, with a minute of silent prayer at 2:46 p.m., the time the earthquake struck. Emperor Naruhito and Empress Masako will be in attendance.

—Alex Newman contributed to this article.