Another earthquake caused a tsunami that hit the Fukushima area.

Fortunately it was small and did not affect the nuclear plants. But what about the next one? The cleanup will take decades. If a big tsunami comes in the coming year, it will wash away the used fuel that remains on the site. It could even cause a fission reaction if it pushes the used fuel rods, stored in a pool, together and causes criticality.

Have they built a tsunami defense dam to protect against this?