History and current status of village road paving project using scallop shells - 2001 to 2020s

History and current status of village road paving project using scallop shells - 2001 to 2020s

In the early 2000s, a project to reuse scallop shells began in Hiradate Village, Aomori Prefecture. The village is known for its abundant scallop fishing, but behind the scenes, approximately 5,000 tons of scallop shells were discarded annually, creating an environmental problem. To solve this problem, a technology was developed to recycle scallop shells and reuse them as road pavement material.

In the initial stages of the project, technology was established to crush scallop shells, process them into fine granules, and mix them into asphalt to create an environmentally friendly pavement material that is still durable. The lime quality contained in the shells also enhances the strength of the pavement material, and this technology was introduced into the pavement construction of the village road in Hiradate Village. As a result, the recycling of shells, which used to be waste, was promoted, and the project was expected to simultaneously achieve environmental conservation and waste reduction. The village-wide effort was also strengthened through collaboration with local companies.

In the 2020s, this scallop shell recycling project took a further step forward. The recycling technology spread throughout Aomori Prefecture and was adopted by other municipalities. Scallop shells now account for about 20% of pavement material, and about 80% of shell waste is effectively utilized. This initiative has greatly reduced the environmental impact, and the recycling technology has spread beyond the village.

In Hiradate Village, a local recycling company, Hiradate Recycle Co., Ltd. played a central role in this project, partnering with major construction companies Obayashi Corporation and Shimizu Corporation to successfully mass produce pavement materials made from scallop shells. Thanks to this cooperation, more than 100 km of roads are paved with scallop shells each year, and the material is now used not only on village roads but also on prefectural roads and highways.

In addition, the project has expanded beyond road paving materials into the agricultural sector. The lime quality of scallop shells is also effective as a soil conditioner, and farmers in Aomori Prefecture are using fertilizers mixed with scallop shells to prevent soil acidification and improve crop productivity. The reuse of scallop shells is expanding in the agricultural sector as well.

This project is attracting attention both at home and abroad as a successful example of balancing environmental protection and the local economy, and similar technology is being introduced in other regions as well. The scallop shell recycling initiative goes beyond mere waste reduction and is an important step toward building a sustainable resource-recycling society.