The contrast couldn’t be greater. One moment I am in the Iwate Tsunami Memorial Museum in Rikuzentakada, Japan, watching videos of The Great East Japan Earthquake and Tsunami in which towering waves wipe out town after town. I couldn’t help but feeling that the water was a living beast, malevolent and determined as it ripped through buildings, surged up streets, and wreaked unimaginable havoc, death, and destruction. The next moment, I am a five-minute walk from the Museum standing on a 41-foot-high, concrete seawall, watching six-inch waves wash onshore, their susurrating sound calming and benevolent.

For the week leading up to this point, Marjorie and I had been hiking the Michinoku Coastal Trail, which runs for 600 miles along the east coast of the northern part of Honshu, Japan’s main island. Our trip, led by WalkJapan, covered parts of the trail from its northern point of Hachinohe to Kesennuma, about 150 highway miles south. It was an amazing adventure along the coast with steep cliffs, ridge walking, rocky beaches, small towns, a blowhole, lush forests, and verdant ravines, as well as good food and revivifying onsens.

Part of the reason we chose to walk this trail and a main reason it exists, is that all of it passes through areas devastated by the March 2011 earthquake and tsunami, which killed more than 20,000 people (more than 2,500 are still missing). One goal of the trail is to help introduce visitors to this region, known as Tohoku, which totals about 18% of the country with about 7% of the population; it is seldom visited by foreigners.

The tsunami that hit the coast was generated by a 30-foot rise of the sea floor during the magnitude 9.0 earthquake. That land shift displaced the water that created the tsunami that hit the coast. The same thing occurred in 1700 with the Cascadia Subduction Zone, except this tsunami traveled at 500 mph across the ocean.

Some of the most striking aspects of our hike were the extensive seawalls, such as the one in Rikuzentakada, which had been built in response to the destruction. Every town, large and small, and even every little fishing port, that we passed through had a seawall or other similar protective structure. The concrete, which could be 20 to 40 feet tall, stretched for miles in larger bays, wrapping the shoreline in a protective cocoon. Smaller areas might contain only a finger or two of concrete, helping to ameliorate the effects of a wall of water. In these locations, additional protection came from massive (up to 10 feet wide) hollow, concrete tetrahedrons and tetrapods.

We also passed through several valleys where the seawall stretched from valley wall to valley wall. At one, we passed through a tunnel in the wall, large enough for a big truck to pass through. A thick steel door blocked the seaward end of the tunnel though there was also a human-sized door that you could pass through to reach the sea.

A significant challenge of the seawalls is how these great behemoths of concrete separate the sea from the land. The desire for protection seems to have won over the desire to be connected to the water, often leading to communities with historical maritime livelihoods having to adapt their lifeways, and I would imagine, how they define themselves. And then there are the many animal species, now effectively prisoned on one side or another of the wall.

The immense seawalls are not simply the product of the 2011 destruction; they also result from tsunamis that have struck Japan relatively regularly (more than a dozen since 1900). Because such events occur within human memory and in oral and written records, they form a collective consciousness of a community, which guides actions. Despite this information, sadly, people didn’t react by getting to higher ground in 2011, but that quake and subsequent tsunami were also unprecedented as the largest in recorded history. Some people worry, too, that the new higher seawalls are no guaranty of safety and may, in fact, provide a false sense of security.

Despite the extensive seawalls, as I walked along the coast, I found it hard to realize the destruction because of the extensive rebuilding. In a way that was a sign, that so many buildings were so new; it was rare to see pre-2011 structures. But the videos and photographs we saw at the museum, which showed many areas we had walked through in the previous week, clearly illustrated the unprecedented and previously-unimaginable power and devastation caused by the tsunami. It was truly sobering and sad to see and imagine.

Where this hit me most was at a cemetery near Jodogohama Beach, one of the most beautiful spots on our trip. When the tsunami struck the coast, not only did the water kill the living, but in many places it unearthed the dead, completely washing away cemeteries. In the years since, people have collected many thousands of uprooted tombstones, which have been relocated to the nearest cemetery, where they remain, orphaned from their original location because there is neither time nor money to try and figure out where they came from and to return them. Seeing this small testimonial, I couldn’t help but weep for the dead, for the survivors, for the communities.

I feel incredibly fortunate to have spent a week spent hiking the Michinoku Coastal Trail. So many amazing sights, locations, tastes, and new experiences. It was truly humbling to walk by the seawalls and to think about the devastation and tragedy, as well as the unbridled forces of nature of the earthquake and tsunami. On one level it’s hard to walk past the massive encasements of concrete and not wonder about what is being lost as the walls sever the connection between land and sea but watching the videos of the tragedies, it’s easy to understand why the walls have gone up. We all want to protect our homes and businesses and families.

I often celebrate geology and the geological links between people and place but I also recognize its potential to change people’s lives. It is important to be reminded of this fact and the awesome power that always lurks below and to not think that we have dominion over the planet. Thinking otherwise is a sure way to disaster; nature always bats last.

If you have missed my mellifluous voice, here’s a link to new podcast produced by HistoryLink, which is an interview with me about Douglas firs.

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