Japan’s concrete seawalls may protect the coastline from tsunami, but villagers say it feels like jail


Concrete is cheap and strong, but even locals who have been through many disasters say they hate the walls between them and the ocean

Reuters |

Latest Articles

Covid-19 could cost students close to US$17 trillion in lifetime earnings

Hong Kong Paralympic athlete calls for more education, support for disabled people

White House confirms boycott of 2022 Beijing Olympics

Scientists discover new dinosaur with slashing tail weapon

Explainer: What does it mean to be transgender, and how can you support your trans friends?

Shinkawa Town, Miyako, Iwate during the 2011 tsunami. The moment the "black wave" rushed over the concrete breakwater and hit the city.

The Pantheon and Colosseum in Rome show how strong concrete is. It is made from sand, small stones, water and clinker, a lime-based binder that has to be baked in very hot ovens. The most widely used cement today is Portland cement which was patented as a form of “artificial stone” in 1824 by Joseph Aspdin in Leeds, Britain. This was later combined with steel rods or mesh, known as rebar, to create reinforced concrete, the basis for skyscrapers such as the Empire State Building.

Rivers of cement were poured after the second world war, when it offered a cheap and simple way to rebuild cities ruined by bombing. It was used in an ever-growing number of dams, bridges, ports, city halls, university campuses, shopping centres and uniformly grim car parks. In 1950, cement production was equal to that of steel; in the years since, it has increased 25-fold, more than three times as fast as steel has.

While some people think it is ugly, concrete is seen as a way to make style, size and strength affordable for the masses.

Escape from concrete jungle fever in Hong Kong's best urban parks

The classic example is Japan, which used concrete in the second half of the 20th century with such enthusiasm that the country’s government was often described as the doken kokka (a construction state).

At first it was a cheap material to rebuild cities damaged by fire bombs and nuclear warheads in the second world war. Then it provided the foundations for a new model of super-rapid economic development: new railway tracks for Shinkansen bullet trains, new bridges and tunnels for elevated expressways, new runways for airports, new stadiums for the 1964 Olympics and the Osaka Expo, and new city halls, schools and sports facilities.

But there is only so much concrete you can usefully lay without ruining the environment. People began to realise this in the 1990s, when even the most creative politicians struggled to justify the government’s stimulus spending packages. This was a period of very expensive bridges to sparsely inhabited regions, multi-lane roads between tiny rural communities, cementing over the few remaining natural riverbanks, and pouring ever greater volumes of concrete into the sea walls that were supposed to protect 40 per cent of the Japanese coastline.

In his book Dogs and Demons, the author and longtime Japanese resident Alex Kerr complains about the cementing over of riverbanks and hillsides in the name of flood and mudslide prevention. Runaway government-subsidised construction projects, he told an interviewer , “have wreaked untold damage on mountains, rivers, streams, lakes, wetlands, everywhere — and it goes on at a heightened pace. That is the reality of modern Japan, and the numbers are staggering.”

He said the amount of concrete laid per square metre in Japan is 30 times the amount in America, and that the volume is almost exactly the same. “So we’re talking about a country the size of California laying the same amount of concrete [as the entire US]. Multiply America’s strip malls and urban sprawl by 30 to get a sense of what’s going on in Japan.”

Test how changing the proportions of cement, water and other elements affects its properties

Traditionalists and environmentalists were horrified – and ignored. The cementation of Japan ran contrary to classic ideas of beauty – ideals of harmony with nature and an appreciation of mujo (impermanence). But Japan lives with the constant danger of earthquakes and tsunamis. Everyone knew the grey banked rivers and shorelines were ugly, but nobody cared as long as they could keep their homes from being flooded.

Which made the devastating 2011 Tohoku earthquake and tsunami all the more shocking. At coastal towns such as Ishinomaki, Kamaishi and Kitakami, huge sea walls that had been built over decades were swamped in minutes. Almost 16,000 people died, a million buildings were destroyed or damaged, town streets were blocked with beached ships and port waters were filled with floating cars. It was a still more alarming story at Fukushima, where the ocean surge engulfed the outer defences of the Fukushima Daiichi nuclear plant and caused a level 7 meltdown. The Liberal Democratic party announced it would spend 200 trillion yen (US$1.8 trillion) on public works over the next decade, equivalent to about 40 per cent of Japan’s economic output.

Earthquake and tsunami fears erupt on social media in Japan as 'bad omen' oarfish spotted

Construction firms were ordered to hold back the sea, this time with even taller, thicker barriers. But not everyone thinks they will work. Engineers claim these 12-metre-high walls of concrete will stop or at least slow future tsunamis, but locals have heard such promises before. The area these defences protect is also of lower worth now the land has been largely depopulated and filled with paddy fields and fish farms. Environmentalists say mangrove forests could provide a far cheaper form of protection. Even elderly locals who have been through many tsunami hate the concrete between them and the ocean.

“It feels like we’re in jail, even though we haven’t done anything bad,” an oyster fisherman, Atsushi Fujita, told Reuters. “We can no longer see the sea,” said the Tokyo-born photographer Tadashi Ono, who took some of the most powerful images of these massive new structures. He described them as an abandonment of Japanese history and culture. “Our richness as a civilisation is because of our contact with the ocean,” he said. “Japan has always lived with the sea, and we were protected by the sea. And now the Japanese government has decided to shut out the sea.”

Edited by Doris Wai