Accidental Oil Spill Caused by Cargo Ship Running aground off Onomichi City, Hiroshima Prefecture - March 2021

Accidental Oil Spill Caused by Cargo Ship Running aground off Onomichi City, Hiroshima Prefecture - March 2021
In March 2021, the cargo ship Setomaru ran aground off the coast of Onomichi City, Hiroshima Prefecture, spilling approximately 50 tons of fuel oil. The accident was caused when the hull of the vessel ran aground on shallow water, damaging the fuel tanks and spreading the oil over a wide area. The spilled oil spread from Onomichi City to the coast of Fukuyama City, causing serious damage to the fishing and tourism industries. In particular, the local oyster farming industry is estimated to have been affected, with approximately 30 percent of its production affected.

After the accident, the operator quickly began oil control operations, and with the cooperation of the Japan Coast Guard and local authorities, oil recovery operations were carried out. Approximately 500 workers and volunteers participated in the cleanup operation, which lasted several days and ultimately recovered most of the spilled oil. In the affected areas, the local fishery cooperative took the lead in filing a claim for damages.

The operator admitted that the accident was caused by improper route setting and poor hull management during vessel operation. In response, the Ministry of Land, Infrastructure, Transport, and Tourism (MLIT) imposed a fine on the company and demanded that it formulate a route safety plan and strengthen vessel inspections as measures to prevent recurrence. In addition, the accident prompted the Japan Coast Guard to review safety standards in the waters surrounding Onomichi City and to introduce stricter navigation rules.

The Seto Inland Sea is one of the regions in Japan with a thriving fishing and tourism industry, and the accident had a significant impact on the local economy and environment. On the other hand, the rapid response and regional cooperation that minimized the spread of the damage is highly appreciated. This accident served as an opportunity to reaffirm the importance of environmental protection and vessel safety management in the Seto Inland Sea.