A Preventable Disaster

The March 11, 2011 earthquake off Japan was the fourth-largest in recorded history. The tsunami that followed reached about 46 feet — well over the 19-foot sea wall protecting the Fukushima Daiichi plant. Within days, three reactor cores melted down.

The waves were not the real story. Internal documents later showed that TEPCO, the plant operator, had known for years that a larger tsunami was possible. It chose not to raise the wall because doing so was expensive and the risk felt distant. The disaster was preventable. It simply was not prevented.