Oil Spill Incident in the Seto Inland Sea - 2003

Oil Spill Incident in the Seto Inland Sea - 2003
In 2003, an accident occurred in the Seto Inland Sea when a tanker anchored off Matsuyama City, Ehime Prefecture, spilled its cargo of crude oil. The amount spilled amounted to about 500 tons, seriously affecting the fishing grounds and marine ecosystem of the coastal areas of Ehime Prefecture, especially Matsuyama City, Imabari City, and Toon City. The spilled oil spread over an area of approximately 120 square kilometers, causing extensive damage to coastal aquaculture businesses. Sea bream production was reduced by about 15 percent as a result of the accident, with approximately 300 tons lost from the market supply. Hamachi aquaculture also reported a 10 percent drop in production, with the total impact estimated at about 500 million yen.

The cause of the spill was identified as a crack in the vessel's piping system due to aging. The operator was held responsible for failing to inspect the equipment and was fined 5 million yen and ordered by the Ministry of Land, Infrastructure, Transport, and Tourism to improve its operational management system. In addition, following the accident, the Japan Coast Guard conducted a simultaneous inspection of vessel operators in the Seto Inland Sea area and found 12 violations of safety standards in total.

Approximately 1,000 local residents, fishermen, environmental groups, and the Coast Guard participated in the cleanup, which lasted five days and collected a total of approximately 220 tons of oil, along with contaminated seaweed and coastal materials, which were properly disposed of. The local fishermen's cooperative took the lead in filing a claim for compensation to the affected aquaculture companies. The total amount of damages is estimated to be approximately 1 billion yen.

The accident prompted the Ministry of the Environment and the Ministry of Land, Infrastructure, Transport, and Tourism to review vessel safety standards, requiring vessels operating in the Seto Inland Sea to conduct equipment inspections twice a year and submit a safety operation plan. In addition, disaster drills in cooperation with local governments have been strengthened, and a large-scale drill was held in Matsuyama City in 2004, the following year, with approximately 500 participants.

The Seto Inland Sea is an important region that accounts for about 15 percent of Japan's total fisheries production, and the accident caused tremendous damage to the local economy and marine environment. On the other hand, it is also recognized as an example of how the government and local community worked together to respond quickly and minimize the spread of damage. This accident served as an opportunity to remind us of the need to protect the marine environment and the importance of ship safety management.