Fukushima Prefecture significant event Aftermath of the 2011 Tōhoku earthquake and tsunami
In the aftermath of the earthquake and tsunami that followed, the outer housings of two of the six reactors at the Fukushima Daiichi Nuclear Power Plant in Ōkuma exploded followed by a partial meltdown and fires at three of the other units. Many residents were evacuated to nearby localities due to the development of a large evacuation zone around the plant. Radiation levels near the plant peaked at 400 mSv/h (millisieverts per hour) after the earthquake and tsunami, due to damage sustained. This resulted in increased recorded radiation levels across Japan. On April 11, 2011, officials upgraded the disaster to a level 7 out of a possible 7, a rare occurrence not seen since the Chernobyl disaster in 1986.
Several months later, officials announced that although the area nearest the melt down were still off limits, areas near the twenty kilometer radial safe zone could start seeing a return of the close to 47,000 residents that had been evacuated.
Landmark event Key happening Pivotal occurrence Momentous incident Notable episode