Crushing it…? A first national mapping of the Norwegian construction aggregates system using Material Flow Analysis
摘要
Norway produces and consumes construction aggregates—sand, gravel, and crushed rock—at one of the highest per capita rates in Europe while increasingly challenged by local resource constraints, longer transportation, and inefficient material use. Yet, the national system governing aggregate management has remained largely unexplored. This study applies a national-scale Material Flow Analysis to quantify the production, use, and end-of-life pathways of aggregates in Norway in 2021. Our model draws on diverse data sources and novel estimation approaches to integrate mined crushed and natural aggregates, construction excavation materials (CEMs), and aggregates occurring in manufactured materials and construction and demolition waste. Findings reveal that Norway produced over 90 Mt of mined aggregates—equivalent to 16.7 t per capita—of which 30% were exported. The domestic demand of 12.8 t per capita was largely met by crushed rock, with road infrastructure accounting for the largest share of stock inputs. Excavation in construction generated at least 28.7 Mt of CEMs, yet only 20% substituted mined aggregates in building and infrastructure applications. Less than 10% of end-of-life aggregates re-entered the system, indicating low circularity. Our findings highlight key data gaps, especially regarding CEMs, and underscore the potential of excavation materials to enhance resource efficiency. By providing a comprehensive overview of the Norwegian aggregates system, this study offers essential insights for sustainable resource management. It emphasizes the critical role of robust maps of material systems, information sharing, and project-scale material coordination to reduce environmental impacts and enable circular construction practices. This article met the requirements for a gold-gold JIE data openness badge described at http://jie.click/badges.