2011 Tohoku Earthquake and Tsunami

Published November 29, 2019

There are some places on the Earth which are more prone to disaster than others. Whether that’s due to geology, meteorology, or any other factor, those who live in such places have to understand the risks, and prepare accordingly.

However, when nature’s fury is unleashed, even the most well-prepared people can face devastation.

Sitting on the Pacific Ring of Fire, Japan is amongst the world’s most seismically active countries. With around 1,500 earthquakes a year, they are simply a matter of fact, and modern buildings are designed with this in mind. Japanese phones have an earthquake alert system built in to them, and an annual Disaster Prevention Day sees widespread preparation drills with over a million people taking part.

Although most of these quakes are small, many barely noticeable, there have been occasions when they have wreaked havoc across the country. In 1923, Tokyo was rocked by the 7.9 magnitude Great Kanto earthquake; in 1995, the 6.9 magnitude Great Hanshin earthquake brought destruction to the city of Kobe.

Both were overshadowed in 2011 by the Tohoku earthquake, also known as the Great East Japan Earthquake.

It was preceded by a number of foreshocks; one, on the 9th of March, was itself larger than the Kobe earthquake at a magnitude of 7.2, but seismologists were still taken by surprise when the main earthquake hit at 2:46pm on Friday, the 11th of March.

The earthquake struck in the Japan Trench, an offshore area where the Pacific tectonic plate meets the Okhotsk microplate, upon which Japan’s northern island of Hokkaido and the Tohoku region of the larger island, Honshu, sit. This is a subduction zone, so-called because the Pacific plate slides, or subducts, beneath the Okhotsk plate. This motion causes the plates to bend and flex against each other; when pressure builds up, and eventually snaps, it causes a megathrust earthquake.

There was some initial confusion about the magnitude of the Tohoku quake. Tomoaki Ozaki of the Japan Meteorological Agency told a Discovery channel documentary, “The magnitude which was shown on the monitor was pretty big, so I thought it might be wrong, the readings must be calibrated incorrectly.”

They were not. Although initially reported to be a 7.9 magnitude quake, it was upgraded more than once; the USGS finalised its magnitude at 9.1.

The epicenter was 130 km, or 80 miles, east of Sendai, and 373 km, or 231 miles, northeast of Tokyo. Despite the distance, and despite the fact that many buildings there are built specifically to withstand earthquakes, it was still felt strongly in the capital city.

Dr Satoko Oki, a seismologist at the University of Tokyo, told filmmakers,

“My office is in a base isolation building, so it should not move, but still I couldn’t even stand up. That was the biggest and longest earthquake I’ve ever experienced. This earthquake is one of the top five in largest earthquake, ever. I mean, on Earth.”

Closer to the epicenter, it was even worse.

Futoshi Toba had been elected mayor of Rikuzentakata, a city in Iwate prefecture, just a month before, and was in his office when the earthquake struck. In his book, “Let’s Talk About It: What Really Happened in the Disaster Area”, Toba wrote:

“The shaking was unlike anything I’d ever experienced before. “This is going to be bad…” I tried to leave my office to give instructions to the employees, but with the neverending shaking, bookshelves began toppling and soon the television fell from the shelf. As we tried to leave the room, we had to hang onto something in order to stay upright.”

Although most earthquakes last only a few seconds, this one lasted for several minutes – three to five, although many survivors said it felt like much longer.

When an employee reported that a floor had collapsed almost beneath his feet, Mayor Toba decided to evacuate City Hall, gathering his employees outside.

People frantically calling to check on relatives quickly found out that the mobile phone network had failed; electricity supply was also down in many areas, so access to vital information was crippled.

Toba continued:

“It was then that a large aftershock hit followed by an announcement warning of an impending large tsunami… As we were in the parking lot we were able to receive information from a car radio, the only mode of communication left. Even now I do not really believe that many of the citizens thought a tsunami would really hit. Only a year before, the Japanese Meteorological Society had issued a warning of a two-meter high tsunami after the earthquake in Chile, prompting extraordinary measures. Highways were closed and we were on alert for a whole day. The tsunami never came. Some of the public felt they had been tricked, and many were heard to say, “Well, that was stupid.” With this false alarm fresh in our memory, people still evacuated but probably thought somewhere, “It won’t come this time either.”

Taeko Kanno also lived in Rikuzentakata. She later told her story to her friend Yachiyo Nakazawa, who recorded it in her book “Tsunami: The Stories of my Friends in Rikuzentakata.” Ms Kanno recalled that, after the earthquake, the toilet at her hair salon had overflowed. She started to clean it, until she heard a crowd of people moving down the street.

“They did not look in a hurry, so she went outside in sandals. One of her neighbours told her, “A tsunami is coming! Evacuate!” She went back into her house, changed into shoes and locked the door. Then with the car key and a handbag she headed toward the Civic Center designated as an evacuation site.”

Ryoichi Usuzawa lived In Otsuchi, another town in Iwate Prefecture. He, too, felt calm.

“When the shaking finally stopped, my wife called from downstairs, “Otosan, a tsunami is coming, let’s run for it!” Neither the TV nor the lights were working. I switched on the radio, and they were saying the tsunami would be three meters high. We had lived on the same land since my father’s generation, and I thought, “It would never make it up here.” I told myself, “Calm down, calm down,” and I continued tidying up all the mess. Then I started fixing the TV. My eldest son ran home from work, and he also told me the tsunami was coming and we should run. But even then, I told him, “Calm down -there is no way the tsunami will come this far.””

And Yoko Yamakage, another Otsuchi resident, also took her time. She left her office to check on her elderly mother at home, then returned to her office to collect valuables before going back home to collect her mother and evacuate. But by then, it was too late.

“When I got home, my mother was still sitting on the sofa. I don’t remember why, but I went upstairs. As I was about to walk back down the stairs, I took a look at one of the rooms upstairs. Through the window of that room I saw a big house drifting from the south.”

When the earthquake struck, the action of one tectonic plate snapping over the other displaced the ocean above it – like slapping the bottom of a basin of water. And it wasn’t just a little “slap” either; the fault was about 450km long and 200km wide, and the shift was measured at 24m east-southeast, thrusting up by 3m.

The resulting waves spread out, like the ripples from dropping a stone in a pond. Unless they reached land, there was little to slow them down, and they reached as far as Antarctica, California and Chile. Naturally, however, the waves reached nearby Japan first.

A computer model of the tsunami’s wave height. Source: Wikimedia Commons.

Although relatively small out at sea, as the sea bed became shallower closer to land, the front of the wave slowed down. This caused the water behind to catch up, and the wave accordingly became taller and taller.

In addition, the shape of the Sendai coast in many areas focussed the wave, so it grew even larger still.

The early alerts – where people were able to hear them – often reported that a 3m wave was expected. But what arrived was much worse.

Just after the tsunami, the Japanese Meteorological Society reported that the height of the tsunami was recorded at 4.1m at Kamaishi, 4.2m at Oarai, and 7.3m at Soma. However, in many places the recording equipment itself was destroyed and the tsunami wave was in fact even higher than that; assessments afterwards recorded inundation heights as high as 12.2m at Sendai Airport and 14.8m at the port of Onagawa.

At Rikuzentakata, Mayor Toba made it to the roof of the four-storey City Hall. Elderly people who used wheelchairs and walkers were carried by younger people – until fire shutters came down at emergency exits. Then those who needed to be carried had to be left on a landing.

Toba recalled that some younger staff members had run back down to the ground.

“They were determined to carry on the rescue of others. None of them came back. They wanted to help as many citizens as possible. However the ravaging waves came crashing in not allowing even the kindest of acts to be rewarded.”

From the roof, Toba saw the waves crashing across his town; local people had always said that there had never been a tsunami large enough to go past the railroad tracks, but he saw the water destroy both the train tracks and the station, and keep going. He described the noise of the buildings being torn apart as sounding like screams echoing.

Footage taken at Rikuzentakata City Hall. From 2:16 onwards, the footage is from the roof during the tsunami.

The 127 people on that roof were lucky; the tsunami was not quite high enough to wash them away. Many others in Rikuzentakata were not so lucky. Hairstylist Taeko Kanno had evacuated to the Civic Center, along with about two hundred other people, expecting to be safe at the top of the three-storey building.

“Everyone believed they would be safe there. However, as soon as she reached the third floor, suddenly a black wind blew in. Then, without warning the wall crumbled and the black waves rushed over people from the windows and ceilings… Taeko-san, too, was slammed to the floor and smashed against it. While desperately struggling under the water, she somehow surfaced herself… She tried to look for something to hang on to and her fingers found a rocker floating near the ceilings… Being tossed about by the waves, she was barely breathing what little air remained close to the ceiling. Pain on her back, legs, face, arms… she fought to endure the tsunami’s torture.”

When the water receded, Ms Kanno was one of only eleven survivors from the Civic Center. She was eventually rescued by helicopter and taken to hospital.

This experience was not as unusual as it should have been. In the three prefectures which were hit hardest, more than a hundred designated evacuation sites were destroyed by the tsunami.

Others did not make it to their designated evacuation points. Katsuko Takahashi, in Otsuchi, was supposed to go to the community centre there. With a friend, she had driven over and was looking for somewhere to park her car when she realised that there was no time left.

“I’m not sure from where exactly but it was nearby, I heard a rasping sound. Even inside the car, you could hear it. We were wondering what it was when, looking through the front windshield, all you could see were houses -houses everywhere. On the roofs, there was a mixture of something rusty, and blue and other things… It didn’t look like a wave. I didn’t know what it was. It may have been a mixture of soil and mud I guess. My friend said, “Let’s get out of the car.” She had already got out from the driver’s side and closed her door by the time I reached for the door handle. I did see her standing there, but didn’t see her again after that. I was frantic. I got out of the car and didn’t even turn around. Even now, I really regret that I didn’t turn around. If I had, I would know exactly what had happened, but as it is I have no idea now, none at all. Now I guess I will have to carry that around with me for the rest of my life. In the end, we were too late.”

Ms Takahashi made it up the hill; her friend was among the missing.

Yoko Yamakage and her mother sheltered in the upstairs hallway of their home as it was carried away by the tsunami.

“The water level rose up to above my chest. About 30 minutes later, the water went down a little, but it rose back up again. There was a dresser in the closet right next to where we were standing, and I made my mother step up on it to keep herself higher above the water. Earlier when I had come home, I opened the closets and also opened all the doors in the house. A fallen glass door was on the floor, so I stepped up on to the frame of it, to keep my face above the water. I held on to the door-frame of the closet with both hands to prop up our bodies while the water had risen up to my chin. It was almost like I had superhuman strength.”

Before they left, Ryoichi Usuzawa’s family shouted to him, “Look after Taro!” While they were able to evacuate, he and the ten-year old Shiba Inu dog were too late. With Taro under one arm, Usuzawa climbed to the roof of his house.

“From there, I could see the whole scene. Otsuchi was a giant washing machine. Round and round the whirlpool spun. Cars and houses that had been swept away came smashing into my house, with a grinding sound. The volume was incredible. Amid the noise, I heard voices saying, “Please help—!” and hissing sounds from leaking propane tanks. Car horns were beeping from alarms that had short-circuited. Although I could hear people calling out, “Please help! Please help!” I couldn’t see anyone. Then there were others who were trapped like I was, being swept away on their rooftops. I could see them being swallowed into the vortex, one by one…
At times, Taro’s leash and collar would come loose, and time after time I contemplated how much easier it would be for myself if I left him behind. But when I saw his whimpering face… We’d shared joys and sorrows over the years, and he used to sleep beside me. When I saw him trembling, I was determined to save him too.”

Across the affected area, footage of the tsunami was taken; on CCTV cameras, from news helicopters, on mobile phones by those fleeing. It is disturbing and often surreal; in many cases, you can see people, either on foot or in vehicles, who are obviously unaware that the tsunami is about to overtake them. A black tide swept across fields, highways, and homes, carrying with it masses of debris and even blazing fires on the water. And then, eventually, the tide turned, carrying much of that debris back out to sea with it.

But the disaster did not end when the water receded. Those who had survived were left with nothing; many were soaked through, and then had to endure the freezing cold weather.

Usuzawa and his dog made it to safety, and were reunited with the rest of the family, but they had a hard night ahead.

“It was very, very cold in the Community Hall. Within 30 minutes, two elderly people passed away right in front of us, and they were carried off to where the partition had been set up. I thought, ah, I might die too. A public health nurse brought me some newspaper, and when I wrapped myself with that, it was so warm. How can a little bit of newspaper be this warm, I wondered… Next morning at about 6 a.m., a fire started at the nearby elementary school, and the blaze spread to the Community Hall. So we moved to the Ogakuchi Meeting Center. When I walked in, saying, “Hello—” there were five people lying down. I called out to them a couple of times, but there was no response. I thought, “Are they…?” They had already passed. Around the nearby embankment, several more poor souls washed up. In the midst of the black mud, there was a light sprinkling of snow. When you witness one person die, you feel pity for them, but when you see dozens of people, it becomes part of the scenery. I couldn’t find words to describe it.”

Yukari Kurosawa worked at the hospital in Otsuchi, and survived the tsunami on its roof.

“The next morning we looked outside again, and just as we suspected -the town had been destroyed by the tsunami. Although we were staring real devastation in the face, it felt like seeing it in a movie. It’s really weird, but I felt calm and detached. I felt like, “what the…” And then the person next to me spoke. “We’re all disaster victims now, aren’t we,” they said. “Huh…” I thought. I couldn’t grasp the reality of it.”

Seizo Sasaki had led a group of people up to Otsuchi’s city hall, on higher ground.

“That night I slept on cardboard. It was freezing… I had nothing to eat for two days, but I had a lot to do, because the water wasn’t working, neither were the toilets…On the third day, finally I got to eat one small ball of rice, and after that we got emergency food supplies from the Self-Defense Forces, so we had no problems getting food.”

After a week, his daughter was able to reach Otsuchi and take him to stay with her in Morioka.

“But my daughter says that every night I had nightmares. Shouting things like “Run!”, “I’ll pull you up, I’ll save you!” I remember seeing people being swept away in my dreams. In reality there was nothing I could do to save them, but in dreams I was trying to help them, shouting. It was horrible.”

Toshikazu Abe, in Otsuchi, was one of the fortunate few who survived actually being engulfed by the tsunami.

“I was so stunned, soaked through and I couldn’t move; and I didn’t have socks on anymore. Then the fires started. We use LPG bottles around my town, and these began to explode. The first one blew up about twenty meters away, sending a column of fire into the air. It was just like one of those Godzilla movies; it felt just like that. Fires started in at least five or six places. A fire broke out near the Kobyou Bridge and spread all over the center of town, soon becoming a sheet of flames. People may think that when you are hit by a tsunami, things won’t burn, but there was kerosene everywhere.”

Emergency response was crippled by the extensive damage to the infrastructure – not only were roads, train tracks and stations destroyed, but in places like Rikuzentakata so were all the landmarks by which anyone would have navigated. Worse still, those who should have been responding were often victims themselves. Mayor Toba wrote:

“I was told one fourth of City Hall employees, and many police officers and fire fighters who were helping people evacuate were missing. It seems immediately after the earthquake, many members of the fire department struggled to help those who were left, and they too were taken. They lost their own lives helping protect the lives of the citizens. If they had just called out to them to get to higher ground they would have likely survived. The same can probably said for the police. My chest felt tight, knowing that now I can only bow my head to these people.”

Rikuzentakata after the earthquake and tsunami. Source: Wikimedia Commons.

For those who had survived, there was a heavy workload. Mayor Toba and his colleagues immediately set about trying to restore some kind of infrastructure. A generator truck brought back power four days after the disaster, telephones were quickly restored, and the water system was prioritised and recovered by the end of June. They set up a temporary City Hall facility to co-ordinate efforts, and it was common to see people sleeping there at their desks because their homes had been swept away.

Reuniting families was one of the big issues in the first days after the quake and tsunami. Because it had happened on a Friday afternoon, children had been evacuated from the schools, parents from their homes and offices, ending up in different places with no idea who had survived and who had not. Getting a definitive answer to that question sometimes took a long time.

Mayor Toba himself dedicated his efforts to the people of Rikuzentakata, feeling that was his duty as their elected leader. He was told the day after the disaster that his two sons were safe – but had not heard any news of his wife. Their eldest son filed the paperwork to add her name to the list of the missing, but it would be almost a month before her body was found.

The Japanese Self Defense Force undertaking search efforts.
Source: Wikimedia Commons

Across the damaged area, thousands of bodies were being uncovered and brought to temporary mortuaries; thousands of townspeople came to those same facilities searching for their loved ones. Once bodies were identified, they would normally be cremated in a traditional ceremony, but in the areas which now needed them most many crematoria had been destroyed too; the families had to find one that was still working and take their loved ones there. There was a limit to how many could be cremated in a day, and issues with finding enough fuel.

There were also bodies who could not be identified; those who were too badly damaged, and those who had no surviving family to look for them. At Rikuzentakata alone, around three hundred such bodies were claimed by the city and taken away for cremation.

The search for bodies, and the effort to identify them, would continue for years. Even now, more than two and a half thousand people are still unaccounted for; it seems likely that these unfortunate victims were washed away into the Pacific Ocean. The dead totalled 15,898.

Japan had suffered the impact of tsunamis before – they gave us the word itself – and there were defenses in place. They had breakwaters built offshore, to deflect and break up waves, and many parts of the shoreline were protected by seawalls and floodgates. So why didn’t they work?

In Rikuzentakata, the scenic shoreline was a tourist attraction – Takata-matsubara, a forest of some seventy thousand pine trees and a nationally designated Place of Scenic Beauty, lay along the beach. There, the seawall was built only 21 feet high (about six and a half metres) so that it wouldn’t obscure the view. The trees themselves were supposed to be part of the tsunami defense, as they would help to break up and slow the wave. However, in the end, the tsunami easily overtopped the seawall, and swept away all but one tree. The rest became part of the tsunami’s battering ram, helping to destroy buildings as it swept inwards.

In some places, the floodgates were little protection because they weren’t able to be closed in time. In Oginohama, four volunteer firefighters were supposed to lock the floodgates. On that day, Masafumi Saito was the only one there. Closing the four gates would take him about twenty minutes, but the tsunami was already in sight by the time he reached the third. Powered by sheer adrenalin, he managed to run to higher ground and escape. The wave reached 32 feet, or 9.7 metres there; the seawall was only about thirteen feet, or just under four metres, high.

According to the Guinness Book of Records, Kamaishi had the world’s deepest breakwater. It had only been finished in 2009, after more than thirty years of construction, and stood nearly 20 feet – about six metres – above the water. Despite this, over a thousand residents were listed as killed or missing after the tsunami.

Full footage of the tsunami at Kamaishi Port, beginning shortly after the earthquake.
The wave can be seen coming over the breakwater just after 18:00.

The problem was that the defenses were simply not built with something of this scale in mind, even though it had happened before – tsunamis of similar height had hit the Sanriku coast in 1896 and 1933. Practically speaking, building defenses that would have worked would, in many places, have been impossibly expensive. The only sure defense against a tsunami of that size would be not being there.

With sufficient notice and appropriate evacuation sites, the people of the coast could be saved even if their homes could not, but again the procedures in place were insufficient. Many evacuation sites were themselves engulfed and washed away.

Choosing an evacuation site for a tsunami is not always easy. The obvious choice is to go to higher ground, where you will be safely above the inundation. However, with limited time to evacuate, not everyone will be within reach of natural high ground. For those people, it’s necessary to construct places of refuge. The roofs of buildings make good refuges, if they’re accessible enough and tall enough. This requires advance planning; making sure that access is available by putting emergency stairs on the outside of buildings, and that there is enough space and that people know where to go. Again, in this case, underestimation of the tsunami’s height meant that people went to evacuation sites that didn’t protect them.

The problem is that a tsunami can’t accurately be predicted in advance, any more than the earthquakes or other events that trigger them. Once the earthquake has occurred, a computer model can be used to predict the tsunami height based on the seismic data, but this is not easy to do quickly enough to beat the waves racing towards shore. It’s also not always accurate – as mentioned earlier, Rikuzentakata had had a false alarm before, so people did not always take the alarm as seriously as they should.

There were also many survivors who said that they hadn’t heard any tsunami alarm. The earthquake disrupted the power and communications networks, so they couldn’t hear any alerts being broadcast on television or radio, or receive any warning phone calls. Naturally, any warning system can only help those who can receive it.

Rikuzentakata’s temporary main street, 2012. Source: Wikimedia Commons

In Rikuzentakata, recovery efforts began quickly, with construction of the first temporary housing starting just a week after the disaster. However, they were often hampered by strict government regulations.“We did finally receive gasoline, but… The instant the Self Defense Forces tried to pump the gas, there was an order from above saying, “This gasoline was given from another government agency so the Self Defense Forces cannot pump it. They can deliver, but don’t let the Self Defense Forces touch the nozzle!” We finally got the gasoline we so desperately needed. That it couldn’t be pumped was idiotic.”

However, he [Mayor Toba] had soon put into place a recovery plan; the city would be rebuilt on higher ground, and a line of cherry trees – called sakura in Japanese – would be planted to mark the extent of the tsunami’s damage. A memorial park would be built for people to pay their respects and learn about the disaster.

It would not be easy; in an interview earlier this year Toba said,

“There’s not a lot to be happy about because recovery is painfully slow. It’s tedious and everywhere, every day there are reminders of loss, of what was, what used to be. There’s also a general undercurrent of dissatisfaction with me, the government and how slow the process is. I said before that no one can prepare for something like this, and I truly believe all manuals and handbooks on recovery policy are useless in the face of such a catastrophe. I’ve done the best I could as mayor over the past eight years, but I know many in the town are not happy; and this pains me.”

Rikuzentakata is, of course, not alone in their troubles; across the damaged coastline the earthquake and tsunami left around 25 million tons of debris that needed to be cleared up, processed, and recycled.

As of March 2017, the Japanese Reconstruction Agency reported that they were still supporting 123,000 evacuees; relocation projects were 60% complete, and public housing developments 78% complete. 83% of farmlands had recovered, 91% of seafood processing facilities had re-opened, and tourism in the Tohoku area had reached 127% of its pre-earthquake numbers.

Source: Unsplash

However, what I’ve told you so far is still only part of the story. The other part, a part which has a huge impact not just on the recovery of the area but the future of the country as a whole, concerns events at the Fukushima Daiichi nuclear power plant. Join me next time for that story.

Thanks this episode go to:

I’d like to say a special thank you to Patreon supporters:

Suzanne Morley
Skeleheron
Okamifan1
Michael Fay
MJ
detectiverj
Amanda
Lesley Slaney
LouLi
Mish Liddle
Missa
Scott RC
Shana Gitnick
Teddy Gingerich
Will Friedrichs

and to all of you for listening and reading. Supporting the Great Disasters podcast on Patreon can give you access to exclusive content, and helps the show keep going.

You can also support the show by buying me a coffee on Ko-Fi.