Fudai Floodgate, Flood control structure in Fudai, Japan

The Fudai Floodgate is a concrete barrier 15.5 metres high and 205 metres wide, standing about 300 metres from the mouth of the Fudai River in Iwate Prefecture. It has large metal gates that are closed remotely or by hand to block tsunami waves. A prefectural road and a school access road pass through the structure via dedicated gates.

After the 1933 tsunami killed many people along this coast, the village mayor at the time, Kotoku Wamura, began pushing for a permanent barrier. The gate was finally completed in 1984, after decades of negotiations and opposition over its cost.

The gate's name is used locally as shorthand for the village's decision to stay rather than relocate: when the barrier was planned, moving the whole settlement was considered and rejected in favour of building it. The structure is also a meeting point in the village's disaster memory, cited by mayor Hiromu Fukawatari after 2011 when he credited earlier residents' efforts with saving the village.

The floodgate can be seen from the outside at any time by walking along the coast road, and no admission is required. Clear weather makes it easier to take in the full scale of the structure and its position at the water's edge.

The gate's 15.5-metre height was not arbitrary: Mayor Kotoku Wamura, born in 1909, remembered a tradition that a 15-metre wave had struck in the Meiji era. He overrode planners who called the height excessive, and in 2011 the tsunami overtopped the gate by about 2 metres without breaching it.