Fukushima Disaster Timeline

On 20 March 2011, the radioactivity of vegetables produced in six prefectures in the Kanto and Tohoku regions exceeded provisional regulation values, prompting concerns about food safety.

On 21 March 2011, the first restrictions were placed on the distribution and consumption of contaminated items in areas affected by radioactive releases from the plant.

As of late 2011, measurements of both the seawater and the coastal sediments suggested that the consequences of the accident for marine life would be minor, despite caesium concentrations being 10 to 1000 times above pre-accident levels.

The number of residents displaced due to the accident peaked at 164,000 in June 2012, and stood at around 119,000 in January 2015.

In April 2014, studies confirmed the presence of radioactive tuna off the coasts of the Pacific U.S., after researchers tested albacore tuna caught before and after the 2011 accident.

In June 2016, the advocacy group International Physicians for the Prevention of Nuclear War asserted that 174,000 people had been unable to return to their homes, and reported ecological damage including malformations in trees, birds, and mammals.

In February 2018, Japan renewed the export of fish caught off Fukushima's nearshore zone. According to prefecture officials, no seafood had been found with radiation levels exceeding Japan safety standards since April 2015, and Thailand became the first country to receive fresh fish from Fukushima prefecture in 2018.

In January 2022, six patients who were kids at the time of the accident sued TEPCO for 616 million yen after developing thyroid cancer.

In August 2011, several top energy officials were fired by the Japanese government, including the Vice-minister for Economy, Trade and Industry; the head of the Nuclear and Industrial Safety Agency; and the head of the Agency for Natural Resources and Energy.

On 5 July 2012, the NAIIC found that the causes of the accident had been foreseeable, and that TEPCO had failed to meet basic safety requirements such as risk assessment, preparing for containing collateral damage, and developing evacuation plans.

Image source: National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission

The investigation committee, supported by public prosecutors and government experts, released its final 448-page investigation report on 23 July 2012.

On 12 October 2012, TEPCO admitted that it had failed to take necessary measures for fear of inviting lawsuits or protests against its nuclear plants.

In 2016, three former TEPCO executives — chairman Tsunehisa Katsumata and two vice presidents — were indicted for negligence resulting in death and injury. They pleaded not guilty, and in September 2019, the court agreed they should not be convicted.

In December 2016, the government estimated decontamination, compensation, decommissioning, and radioactive waste storage costs at ¥21.5 trillion ($220 billion inflation adjusted), nearly double the 2013 estimate. By 2022, ¥12.1 trillion had already been spent.

In March 2017, a Japanese court ruled that negligence by the Japanese government had led to the Fukushima accident by failing to use its regulatory powers to force TEPCO to take preventive measures.

On 30 September 2020, the Sendai High Court ruled that the Japanese government and TEPCO are responsible for the accident, ordering them to pay $9.5 million in damages to residents for their lost livelihoods.

In March 2022, Japan's Supreme Court rejected an appeal from TEPCO and upheld the order for it to pay damages of ¥1.4 billion ($12 million) to about 3,700 people whose lives were harmed by the accident.

On 17 June 2022, the Supreme Court acquitted the government of any wrongdoing regarding potential compensation to over 3,700 people affected by the accident.

On 13 July 2022, four former TEPCO executives were ordered to pay ¥13 trillion ($95 billion) in damages to the operator of the power plant, in the civil case brought by TEPCO shareholders.

In 2013, TEPCO installed additional filters, vents, and other safety systems at Kashiwazaki-Kariwa Nuclear Power Plant in response to lessons learned from the Fukushima accident.

Image source: Kashiwazaki-Kariwa Nuclear Power Plant

TEPCO completed the removal of 1535 fuel assemblies from the Unit 4 spent fuel pool in December 2014, a major milestone in the decommissioning effort.

On 10 September 2015, floodwaters driven by Typhoon Etau prompted mass evacuations in Japan and overwhelmed the drainage pumps at the stricken power plant.

In 2018, tours to visit the accident area began, allowing visitors to see the effects of the disaster firsthand.

In September 2020, The Great East Japan Earthquake and Nuclear Disaster Memorial Museum was opened in the town of Futaba, near the power plant, preserving the memory and lessons of the disaster.

TEPCO completed the removal of 566 fuel assemblies from the Unit 3 spent fuel pool in February 2021. It plans to remove all fuel rods from Units 1, 2, 5, and 6 pools by 2037 and molten fuel debris from Units 1–3 by about 2050.

In July 2022, Japan's Nuclear Regulation Authority approved discharging the treated water into the sea, following a 2020 government committee conclusion that the purified water should be released to the sea or evaporated. Tanks used to store the water were expected to be filled in 2023.