The impact of the flood took out most of the emergency generators that were being used to cool the reactors and spent fuel.

Soon after the earthquake, a tsunami wave of over 14 metres (46ft) in height hit Fukushima Daiichi, overwhelming a defensive seawall and flooding the plant. The impact of a huge wave led to a nuclear meltdown Map showing the location of Fukushima Daiichi nuclear power plant Emergency generators were turned on to cool the remaining decay heat of the reactors and spent fuel. The plant’s systems did their job, detecting the earthquake and automatically shutting down the nuclear reactors. On 11 March 2011 at 14:46 local time (05:46 GMT) the 9.0 MW Great East Japan earthquake (also known as the 2011 Tohoku earthquake) struck Japan, 97km north of the Fukushima Daiichi nuclear power plant. The Fukushima accident was the worst nuclear disaster since the meltdown at the Chernobyl nuclear plant in Ukraine in 1986.

The nuclear incident triggered a mass evacuation, the setting up of a vast exclusion zone around the plant, several hospitalisations due to the initial explosion and ensuing radiation exposure, and a clean-up operation costing trillions of yen. The impact of that terrifying moment is still being felt. Situated in the town of Okuma in Fukushima prefecture, on the northeast coast of Japan, the Fukushima Daiichi nuclear power plant was battered by an enormous tsunami on 11 March 2011, causing a perilous nuclear meltdown and a mass evacuation.

Nuclear reactor meltdown japan 2011