Underneath Norrköping: An Urban Mine of Hibernating Infrastructure

This study examines the subsurface infrastructure in the Swedish city of Norrköping from an urban mining perspective. Urban mining is a broadly defined term for different strategies that regard the built environment as a resource base for materials. In this study, the focus is on three base metals that exist in large quantities in infrastructure parts: iron, copper and aluminium. A special focus is given to the parts of Norrköping’s infrastructure that are not in-use and thus constitute a ”hibernating stock” that contains recyclable metals. The main results of this study are twofold. First, a quantitative assessment of the hibernating stocks of urban infrastructure gives answers to how large the stocks are and where in Norrköping they are located. This was performed using a spatially informed Material Flow Analysis to arrive at a recycling potential in terms of weight and spatial concentration. Second, a qualitative assessment was made regarding how these hibernating stocks of urban infrastructure come into existence. An infrastructure studies perspective was used to outline three patterns with their own sets of ”hibernation” logics. These logics give rise to different prerequisites for the implementation of urban mining in practice. A main argument of this study’s cover essay is that both of the above outlined kinds of knowledge are needed to engage in urban mining with confidence. Thus, the main focus of the cover essay text is to describe how the two different perspectives of Material Flow Analysis and infrastructure studies were combined into a coherent research approach.