Japan one year on: A journey through a world shaken to the core

''The world is heavy on us," says Katsunobu Sakurai, recalling the day that its weight almost crushed the life out of his city. On the morning of 11 March last year, Minamisoma and its mayor were struggling with the same mundane problems as many other small rural cities across Japan: a declining, greying population, creaking public services and a faltering local economy. By nightfall, an existential disaster had engulfed Mayor Sakurai's office, one from which it has yet to re-emerge.

It began with the huge quake that struck off the coast of the city of 71,000 at 2:46pm. Less than an hour later, Mr Sakurai was on the roof of the city office, squinting toward the sea about six miles away. "We could see this huge cloud of dust rising into the air from the Pacific. I asked someone, 'Is that a fire?' Then we realised it was the tsunami." Even as he spoke, the deluge was inundating homes, drowning old people and children alike, sometimes whole families. By evening, bodies were being brought to a makeshift morgue in a local college.

The 11 March quake and tsunami took 630 lives, including 100 children, in Minamisoma. For days, Mr Sakurai wondered if his elderly parents were among the casualties. But instead of looking for them he was dealing with the crisis that would define his city. On 12 March, 23km south of his office, an explosion blew apart the building housing reactor 1 at the Fukushima Daiichi nuclear plant. Operator Tokyo Electric Power and the central government were silent on what was happening. Public television said there was no need for panic. Minamisoma's citizens made up their own minds and fled after rumours of radiation.

Within a few days, the town had almost emptied of people. Twenty-seven thousand – a third of the population – have yet to return a year later. "They're scattered all across Japan," says Mr Sakurai. "We know of some families in America, too. Who knows if they will ever come back?" About 150 of his city's 830 employees are expected to quit this year, what he calls a 'municipal meltdown' brought on by the stress of last year's calamity. "We had to work everything out for ourselves because there was no help from central government. We're seeing the results of that now."

Minamisoma's agony was replicated all along the northeast coast, where the tsunami at some points topped 40 meters. Nineteen thousand people were left dead or missing. Among the terabytes of digital footage from Japan's disaster, one of the most heartbreaking shows fleeing refugees from Rikuzentakata, up the coast from Minamisoma, impotently watching from a hill as a huge muddy wave slowly swallows up their picture-postcard town. Voices behind the shaky handheld camera record the emotions of the crowd, from initial incredulity to horror, then keening despair. Old and young, male and female, weep. An elderly man, possibly the camera operator, keeps repeating "tomete kure, tomete kure" (stop it, please stop it). Afterwards, they were surely thankful to have survived. But in the moment captured on film, the overwhelming reaction was disbelief and for some, perhaps, déjà vu.

Memory and forgetting were life-or-death issues. Akio Komukai, a factory worker, recalls speeding away from the coast in the town of Ofunato after the earthquake struck and meeting children on their way home from school.

"They were walking toward the sea and I rolled down the window of my car and shouted: 'Tsunami tendenko' There's a tsunami coming! You need to run away!'" The youths looked at the 61-year-old and kept walking, an episode one imagines being repeated through the centuries.

Tsunami warnings are as common as muck in the north-eastern Tohoku region – there had been one a few days before 11 March. Mr Komukai, who remembers a 1960 tsunami washing away houses, still wonders who among the children survived. "They didn't believe me," he says. "We forget that the sea is close because we build next to it. Then the tsunami comes and washes away the houses and you can see the sea again. And we're reminded."

The tsunami roared through a huge floodgate in Rikuzentakata, sweeping away 45 young firemen trying to shut the gate, tearing the town of 23,000 people from its roots and leaving behind a gaping landscape that reminded survivors of post-war Hiroshima and Nagasaki.

Journalists who arrived in the town found car navigation systems still directing them to the post office, hospital and other washed-away landmarks. Survivors could be seen picking through the mud for belongings, especially photo albums. In makeshift refugee centres, pictures plucked from the deluge were painstakingly laid out near the entrances in the hope that their owners might claim them – if they had survived.

Today, only the skeletons of steel-structured buildings stand in many of these coastal towns in Iwate, Miyagi and Fukushima prefectures. Two-roomed prefab homes have sprung up in public spaces, housing the roughly 340,000 people displaced by the disaster. The lucky ones, such as Makoto Mikamori and his wife Megumi have already started to rebuild. "It's tough but our community has pulled together so we're managing," says Yoshiko Oikawa, who lost her home near the coast in Ofunato. It will be several years before she gets a new house but she considers herself fortunate because her children are safe: "Some of their friends were not so lucky."

History has repeatedly shown that these communities can rebuild, often with remarkable speed. In 1933, waves up to 28 metres tall demolished much of this coastline, leaving more than 3,000 people dead or missing.

Another huge tsunami up to 38 metres high crashed ashore in 1896, killing 22,000. Ofunato, Minamisoma, Rikuzentakata and other towns have always bounced back, erecting stone monuments at the highest point of the tsunami that stuck their homes, then forgetting their lessons; their faded stone lettering a metaphor for collective amnesia. Recovery this time, however, is less easy to predict.

- The Independent