Concrete walls could ultimately stretch 140 miles along Japan's tsunami-damaged northeast coast. The project's breathtaking scale and cost – as well as doubts about its effectiveness – are drawing ire.
Fear of a giant tsunami prompted Masahito Abe to rebuild his family home on higher ground 20 years ago. In March 2011, his caution paid off when towering waves ripped into the northeast coast of Japan, killing almost 19,000 people, including 40 of Mr. Abe’s neighbors in the picturesque village of Koizumi.
Like tens of thousands of other survivors whose lives have been put on hold for more than three years, Koizumi’s 1,800 residents know that in the coming decades, they and future generations will again be confronted by potentially fatal tsunamis. Yet Abe and other residents in the country’s disaster-prone northeast are now questioning the wisdom of a grand, five-year plan that the government says will protect them and their livelihoods: hundreds of concrete walls stretching 230 kilometers (about 140 miles) along the coast, at a cost of $8 billion.
“It’s madness,” says Abe, a local schoolteacher who points out that the 14.7-meter (about 48-ft.) wall proposed for Koizumi will be lower than the tsunami that inundated the village three years ago. Besides, he adds, villagers now spread out among temporary housing units will begin moving into new homes built on high ground about 1-1/2 miles from the coast later this year.
“We want the government to change the shape of the wall so it suits our needs, not just put up a giant wall with no consideration for local people’s wishes,” he says.
At stake is the pace and shape of the recovery of the tsunami-hit coast: construction cannot begin on sites considered vulnerable to tsunamis until each community decides how, exactly, it wishes to be assimilated into what critics deride as the Great Wall of Japan. And even taking into account Japan’s postwar addiction to protecting its coastline against typhoons, erosion, and giant tsunamis, the scale and cost are staggering.
Under the government plan, hatched within months of the disaster when emotions over the human cost were running high, 440 walls have been or will be built in the three worst-hit prefectures of Fukushima, Miyagi, and Iwate.
The wall proposed for Koizumi alone will cost $230 million and do little more than protect rice paddies, even though local farmers have expressed little interest in replanting their fields.
“The region hit by the 2011 tsunami includes areas that are also regularly hit by typhoons, so historically, from Miyagi to the north the sea wall heights were calculated for tsunami, and to the south for typhoons,” says Yoshiaki Kawata, a professor at Kansai University and one of Japan’s leading experts on disaster prevention and management. “In cases like the last tsunami, the best approach is to evacuate people. And in areas that are used exclusively for agriculture, barriers aren’t necessary.”
Prof. Kawata advocates a multilayered approach that would combine quicker, easier evacuation routes and procedures, along with physical barriers comprising forests and greenbelts, with elevated areas carrying roads and railway lines. In cases where evacuation would be difficult, he believes that whole residential areas should be built on elevated ground.
“The goal is how to build more vibrant towns and cities than before,” he says. “We’re not saying that people just move to a higher place and build a huge breakwater. The most important thing is for residents to discuss sea walls, but not to assume that they are their only option.”
The sheer scale of the destruction caused by the 2011 disaster shook public confidence in the effectiveness of concrete barriers. In the village of Fudai, a 50-ft.-high wall spared the lives of 3,000 locals; but in Kamaishi city, whose huge sea wall crumbled on impact with the tsunami, and most other locations, simple barriers proved no match for the power of the ocean.
"Sea walls have the potential to save lives wherever they are built, provided the tsunami does not exceed the simulated height and run-up pressures,” says Christian Dimmer, an assistant professor in the urban studies department at Tokyo University. “The problem is that you can’t predict how high the next tsunami will be, so sea walls can never give you 100 percent security. There will always be a risk.”
While Prime Minister Shinzo Abe and local leaders push for construction of sea walls and the much-needed economic activity they will create, campaigners accuse the authorities of ignoring local people when coastal defense was first discussed in the wake of the disaster.
“People who experienced the tsunami learned that they could not defeat nature,” says Akihiko Sugawara, chairman of the Kesennuma chamber of commerce and industry and founder of the Kesennuma city sea wall study group.“They learned that the best chance of survival is to evacuate quickly, but still the government told us that we’d be protected in [the] future by sea walls – even against tsunamis of the size that come along only once every 100 years or so.
“We pushed the government to design evacuation routes and procedures and to put them into place as quickly as possible, but we were ignored.”
Skeptics say that they are not opposed to sea walls per se, but insist that differences in size, location, and topographical features in each affected community militate against the government’s one-dimensional solution.
But more than three years after the disaster, and with 230,000 people still displaced, time to consider more imaginative approaches is running out, says Satoko Seino, a professor in the graduate school of engineering at Kyushu University.
“Regardless of the need for more discussion, the urgent nature of the project and the interests of the construction industry will suppress criticism so that firms can get the job finished on deadline,” Ms. Satoko says. “We relied on the usual Japanese way of doing things, which meant there was no room for innovation.”
In Koizumi, the debate is chipping away at the villagers’ enthusiasm to put their community back on the map from which it physically disappeared just over three years ago. For every sea wall skeptic, there are households that have already sold their land to make way for construction of the concrete barrier.
“I don’t want the sea wall issue to divide people,” Yoshitaka Oikawa, a local councilor, told a recent public forum on the issue. “I can see the debate is already weakening their determination to rebuild their village together.”
Koizumi resident Abe, meanwhile, says the indiscriminate construction of sea walls will only strengthen Japan’s international image as a “concrete fortress.”
“The tsunami was a force of nature, so I can forgive it for the destruction and misery it caused,” he says. “But for humans to ruin their own environment.… I can never forgive that.”