For decades, Kotoku Wamura was ridiculed for his insistence on constructing a massive floodgate to protect his village. As mayor of Fudai, a small Japanese town with just over 3,000 residents, he championed a project that cost ¥3.56 billion (approximately $30 million in 2011) and took over a decade to complete. Many saw it as an unnecessary expense — until a 9.1-magnitude earthquake triggered a devastating tsunami in 2011.

The wave wiped out entire towns along Japan’s coastline. But in Fudai, where Wamura’s floodgate stood, the village remained untouched.

“However you look at it, the effectiveness of the floodgate and seawall was truly impressive,” current Fudai Mayor Hiroshi Fukawatari said in 2011.

Here’s the longer story.

A man on a mission

Kotoku Wamura’s political career spanned over 40 years, beginning in the post-war period. He was elected mayor ten consecutive times, leading Fudai through an era of change and growth. The village, nestled about 320 miles from Tokyo, relied on fishing and tourism — both of which depended on the sea. But Wamura knew better than most how dangerous the sea could be.

He had been born in 1909 and witnessed the harrowing 1933 tsunami, which reached a height of 28.7 metres (94 ft). He had also heard stories of the 1896 tsunami, which was even worse. In Fudai, these tsunamis killed hundreds of people.

From an early age, Wamura resolved that Fudai would not suffer the same fate again.

“When I saw bodies being dug up from the piles of earth, I did not know what to say. I had no words,” Wamura wrote of the 1933 tsunami in his book about Fudai, “A 40-Year Fight Against Poverty.”

As a boy, Wamura says, he’d heard from an elder in his village that giant waves had consumed the village in the past. The elder even mentioned that there used to be a stone up a hill showing how high the water level was.

This story seems very plausible as Japan is riddled with warning stones showing previous tsunami levels. Wamura swore this wouldn’t happen again. So, he made it his mission to ensure the village would be safe from tsunamis.

A controversial floodgate

In 1967, he got the local government to build a 51-foot seawall to protect the homes from the village’s fishing port. The height seemed excessive to some, but in the end, it was deemed acceptable.

But then, Wamura moved on to the more important part of his plan: a floodgate, as tall as the seawall, for the cove where most people lived.

Building any large structure on the coast is a challenging endeavor, both financially and logistically. But, for a tight-knit community with limited resources, investing a large sum and over a decade’s work in a project that might never be “tested” by a major tsunami understandably drew skepticism.

But Wamura insisted. He never forgot how much damage the sea could cause.

It wasn’t that people were against the idea of a floodgate, it was just the size. It was too big. Officials first pushed for 20 feet, then 30 feet, then 35 feet. Wamura wouldn’t budge, and in the end, he got his way.

Construction began in 1972, although many weren’t convinced. The plan was derided, especially when it took until 1984 to complete. By then, Wamura was close to the end of his political career and retired in 1987. It was his last major project.

As he retired, Wamura gave a small speech. “Even if you encounter opposition, have conviction and finish what you start. In the end, people will understand,” he said.

He died in 1998, as political adversaries mocked him and his floodgate.

But he was vindicated in 2011.

Villagers now visit his grave to pay respects

If there’s a country that’s prepared for earthquakes, it’s Japan. Japan lies at a dangerous tectonic edge and routinely has major earthquakes. But the 2011 earthquake shattered all forecasts. It came in as a triple whammy, with the earthquake itself, the tsunamis it caused, and the radioactive danger that came from damaging the Fukushima nuclear plant.

Fudai, too, was in the tsunami’s path. Waves rushed toward the village, leveling everything outside the floodgate. Trees fell, homes near the coastline were destroyed, and ships were swept away. But when workers activated the floodgate’s remote system, the massive steel panels closed. One fireman even had to manually shut a jammed panel.

When the tsunami hit, the village behind the floodgate was completely spared.

No buildings suffered major damage. The only fatality was a person who had gone to check on his boat in the port — outside the wall’s protection.

Wamura didn’t get to see how his floodgate protected the village. But he saved hundreds of lives. Years after his passing, villagers still honor him for refusing to compromise on what he believed was necessary to protect them. Some visit his grave to pay respects.

His legacy endures as a reminder that careful planning can avert disaster, and that conviction — and the will to act on it — can outlast the skepticism of an entire generation, echoing through the decades to safeguard the future.