Aftermath of the disaster
- Also called:
- Great Sendai Earthquake or Great Tōhoku Earthquake
- Date:
- March 11, 2011
- Context:
- earthquake
- tsunami
- Fukushima accident
- On the Web:
- CORE - Implications of the 2011 Great East Japan Tsunami on sea defence design (PDF) (Dec. 16, 2024)
Casualties and property damage
Initial reports of casualties following the tsunami put the death toll in the hundreds, with hundreds more missing. The numbers in both categories increased dramatically in the following days as the extent of the devastation—especially in coastal areas—became known and rescue operations got under way. Within two weeks of the disaster, the Japanese government’s official count of deaths had exceeded 10,000; more than one and a half times that number were still listed as missing and presumed dead. By then it was evident that the earthquake and tsunami constituted one of the deadliest natural disasters in Japanese history, rivaling the major earthquake and tsunami that had occurred off the coast of Iwate prefecture in June 1896. As the search for victims continued, the official count of those confirmed dead or still missing rose to about 28,500. However, as more people thought to be missing were found to be alive, that figure began to drop; by the end of 2011 it had been reduced to some 19,300.
Coastal cities and towns as well as vast areas of farmland in the tsunami’s path were inundated by swirling waters that swept enormous quantities of houses, boats, cars, trucks, and other debris along with them. As the extent of the destruction became known, it became clear how many thousands of people were missing—including, in some cases, half or more of a locality’s population. Among those who initially were unaccounted for were people on a ship that was washed away by the tsunami and passengers on several trains reported as missing in Iwate and Miyagi prefectures. The ship was later found (and the people on board rescued), and all trains were located as well.
Ultimately, the official total for the number of those confirmed dead or listed as missing from the disaster was about 18,500, although other estimates gave a final toll of at least 20,000. Of those, fewer than 100 were from prefectures other than Iwate, Miyagi, and Fukushima. Miyagi prefecture suffered the greatest losses, with some 10,800 killed or missing and another 4,100 injured. The great majority of those killed overall were drowning victims of the tsunami waves. In addition, more than half of the victims were age 65 years or older.
Although nearly all of the deaths and much of the destruction was caused by the tsunami waves along Japan’s Pacific coastline, the earthquake was responsible for considerable damage over a wide area. Notable were fires in several cities, including a petrochemical plant in Sendai, a portion of the city of Kesennuma in Miyagi prefecture, northeast of Sendai, and an oil refinery at Ichihara in Chiba prefecture, near Tokyo. In Fukushima, Ibaraki, and Chiba prefectures thousands of homes were completely or partially destroyed by the temblor and aftershocks. Infrastructure also was heavily affected throughout eastern Tōhoku, as roads and rail lines were damaged, electric power was knocked out, and water and sewerage systems were disrupted. In Fukushima a dam burst close to the prefectural capital, Fukushima city.
Northern Japan’s nuclear emergency
Of significant concern following the main shock and tsunami was the status of several nuclear power stations in the Tōhoku region. The reactors at the three nuclear power plants closest to the quake’s epicentre were shut down automatically following the temblor, which also cut the main power to those plants and their cooling systems. However, inundation by the tsunami waves damaged the backup generators at some of those plants, most notably at the Fukushima Daiichi (“Number One”) plant, situated along the Pacific coast in northeastern Fukushima prefecture about 60 miles (100 km) south of Sendai. With power gone, the cooling systems failed in three reactors within the first few days of the disaster, and their cores subsequently overheated, leading to partial meltdowns of the fuel rods. (Some plant workers, however, attributed at least one partial meltdown to coolant-pipe bursts caused by the earthquake’s ground vibrations.) Melted material fell to the bottom of the containment vessels in reactors 1 and 2 and burned sizable holes through the floor of each vessel, which partially exposed the nuclear material in the cores. Explosions resulting from the buildup of pressurized hydrogen gas in the outer containment buildings enclosing reactors 1, 2, and 3, along with a fire touched off by rising temperatures in spent fuel rods stored in reactor 4, led to the release of significant levels of radiation from the facility in the days and weeks following the earthquake. Workers sought to cool and stabilize the damaged reactors by pumping seawater and boric acid into them.
Because of concerns over possible radiation exposure, Japanese officials established an 18-mile (30-km) no-fly zone around the facility, and an area of 12.5 miles (20 km) around the plant was evacuated. The evacuation zone was later extended to the 18-mile no-fly radius, within which residents were asked to leave or remain indoors. The appearance of increased levels of radiation in some local food and water supplies prompted officials in Japan and overseas to issue warnings about their consumption. At the end of March, seawater near the Daiichi facility was discovered to have been contaminated with high levels of radioactive iodine-131. The contamination stemmed from the exposure of pumped-in seawater to radiation inside the facility; this water later leaked into the ocean through cracks in water-filled trenches and tunnels between the facility and the ocean.
In mid-April Japanese nuclear regulators elevated the severity level of the nuclear emergency at the Fukushima Daiichi facility from 5 to 7—the highest level on the scale created by the International Atomic Energy Agency—placing the Fukushima accident in the same category as the Chernobyl accident, which had occurred in the Soviet Union in 1986. Radiation levels remained high in the evacuation zone, and it was thought that the area might be uninhabitable for decades. However, several months after the accident, government officials announced that radiation levels in five towns located just beyond the original 12.5-mile evacuation zone had declined enough that they could allow residents to return to their homes. Although some people did come back, others stayed away, concerned about the amount of radioactive materials still in the soil. Attempts were made in several of those areas to remove contaminated soil. In December 2011 Japanese Prime Minister Noda Yoshihiko declared the Fukushima Daiichi facility stable after the cold shutdown of its reactors had been completed.
In the years following the accident, numerous leaks at the facility occurred at the site where contaminated reactor cooling water was stored. A significant leak occurred in August 2013 that was severe enough to prompt Japan’s Nuclear Regulation Authority to classify it as a level-3 nuclear incident.