Fukushima Daiichi decommissioning and water release

The decommissioning and water management operations at the Fukushima Daiichi Nuclear Power Plant continue amid technical challenges and international scrutiny. After three years of discharging treated water into the ocean, Tokyo Electric Power Company (TEPCO) has released approximately 173,000 tonnes across 22 rounds.

As of late August 2026, the facility has commenced its 23rd release of treated water. This 19-day operation aims to discharge approximately 7,800 tons of water diluted with seawater, with an estimated total tritium content of 1.2 trillion becquerels. These releases are intended to reduce the number of on-site storage tanks to facilitate decommissioning activities, such as constructing facilities for fuel debris retrieval.

Despite these efforts, the total volume of stored water has decreased by only 7% to 7.6% because new contaminated water is continuously generated by groundwater and rain contacting melted fuel debris. While the International Atomic Energy Agency (IAEA) reports no unusual radioactivity in the marine environment, international tensions persist. China, Hong Kong, South Korea, and Russia maintain import restrictions on Japanese seafood due to safety concerns.

Technical assessments have revealed structural damage within the facility, including a 3-meter hole at the bottom of the Unit 3 reactor pressure vessel. TEPCO intends to begin large-scale removal of debris as early as fiscal year 2037. Additionally, repairs have been completed on an expanded solid waste incineration facility that had been offline since February 2024; it is expected to resume operations in August. The long-term decommissioning plan is targeted for completion by 2051.