As an island nation with roughly 30,000 kilometers of coastline, Japan¡¯s connection to the sea is as deep as the ocean itself.
This relationship is one of both of dependence, with most of the country¡¯s population living in coastal areas, and fear, as tsunamis and storm surges periodically threaten communities.
A constant reminder of this complex interplay are the concrete structures that line more than 40% of Japan¡¯s jagged coastline. From seawalls and embankments to wave-dissipating blocks and breakwaters, concrete has been used as the principal line of defense against the forces of the sea throughout the postwar period.
In fact, ¡°Japan¡¯s spending on physical coastal defense has few equals around the world,¡± researchers from Tohoku University wrote in a 2021 paper titled ¡°Social lives of tsunami walls in Japan.¡±
On the island of Amami Oshima in Kagoshima Prefecture, a campaign against the construction of a seawall on Katoku Beach is a rare example of opposition to this kind of infrastructure in Japan.
Standing atop the sand dune that separates the beach¡¯s seaward side from the village of Katoku, views of the ocean are unimpeded.
This stretch of sand, unique in its biodiversity, is nicknamed ¡°Jurassic Beach¡± because its nature recalls that of a prehistoric time. It is the only beach in Japan where a leatherback sea turtle has been recorded laying eggs.
Here, the mouth of the Katoku River, Amami Oshima¡¯s last free-flowing river, shifts naturally, creating a channel that flows parallel to the dune for several months a year and redistributes sand along the beach following a seasonal rhythm.
The beach¡¯s appearance was transformed in October 2014 by two typhoons that uprooted the pandanus trees covering the dune and eroded part of it, leaving the beach thinner and creating a scarp 7 meters from Katoku¡¯s cemetery, which faces the sea.
Residents of Katoku appealed for action to protect the village from future typhoons and a 530-meter-long, 6?-meter-tall seawall was proposed by Kagoshima Prefecture in 2016.
Following a review, the planned structure was shortened to 180 meters. However, the decision remains hotly contested.
Among its fiercest critics is Jean-Marc Takaki, who visited Katoku for the first time in 2010 and moved there two years ago. Takaki is one of 10 plaintiffs engaged in a legal battle with the prefecture to stop the seawall¡¯s construction.
Backed by the conservation group he founded in 2017, Takaki asserts that the beach is the village¡¯s biggest asset and that building a seawall would cause its destruction.
He claims the project also violates Japan¡¯s obligation to...
With your current subscription plan you can comment on stories. However, before writing your first comment, please create a display name in the Profile section of your subscriber account page.