Current Status of Yokohama City Recycled Materials Artificial Reefs Development Project (2020s)

Current Status of Yokohama City Recycled Materials Artificial Reefs Development Project (2020s) In the 2020s, the recycled materials artificial reefs development project has expanded further, centered around Yokohama City. Efforts to protect marine environments and regenerate marine resources are seen as crucial steps toward realizing a sustainable society. This project has become particularly important in coastal areas affected by climate change and environmental issues. ### Advances in Technology and Materials In addition to the conventional use of coal ash, waste concrete, and scallop shells, the project now incorporates **marine plastic** waste and **recycled metals**. The reuse of marine plastic is a key effort in reducing ocean debris, particularly around Japan, while simultaneously contributing to the restoration of marine resources. The new technology enables these recycled materials to function effectively as part of the ecosystem. ### Expansion of Participating Companies Initially, **Hitachi Zosen Corporation**, **Taiheiyo Cement Corporation**, and **Hazama Corporation** were the core companies, but in the 2020s, **Kajima Corporation** and **Taisei Corporation**—two of Japan's leading construction firms—joined the project. This has facilitated further technological innovation and expansion, including the consideration of deploying the project overseas, such as in the coastal regions of **the Philippines** and **Indonesia**, where the installation of artificial reefs is underway through international cooperation. ### Environmental Impact and Data Since the project's inception, approximately **50 artificial reefs** have been installed along the coasts of Miura Peninsula, Kanagawa Prefecture, and the Boso Peninsula, Chiba Prefecture, covering a total area of over **200 square kilometers**. As a result, marine resources have increased by about **15%**, providing stability for the incomes of local fishermen. High-value marine products such as abalone and sea urchins have particularly benefited from this initiative, boosting the local economy. According to data from Japan's Ministry of the Environment, the water quality and biodiversity in the areas where the reefs have been installed have improved significantly. The proliferation of marine plants, which can absorb CO2, has been promoted, contributing an estimated **100,000 tons** of CO2 absorption per year, aiding in efforts to combat climate change. ### Legal Framework and Regional Cooperation In the 2020s, the Japanese government enacted the **Marine Ecosystem Restoration Promotion Act**, establishing a system where companies and local governments cooperate on marine restoration projects, including the use of recycled materials. Yokohama City and Miura City have partnered with local fisheries and businesses to further develop these initiatives. Yokohama City, in particular, has taken the lead by designating a part of Yokohama Port as a model area, using the success of the artificial reefs project there as a basis for expansion to other regions. Thus, the recycled materials artificial reefs development project in Yokohama City in the 2020s continues to achieve greater results, driven by advancements in technology, participation from leading companies, environmental improvements, and the establishment of supportive legal frameworks.