SubCity: Planning for a sustainable subsurface in Stockholm

Abstract

With an expected increase in urbanisation and low-carbon transition efforts, the planning of cities is becoming more challenging, and societies need to rethink how urban infrastructures will be constructed in the future. There is a growing recognition that the use of space below the city will need to be significantly enhanced. However, once transformed, underground space becomes a permanent feature, and major metropolitan areas worldwide are gradually acknowledging the subsurface as a valuable, non-renewable resource, emphasising the necessity for long-term, comprehensive, and sustainable planning of its utilisation. Sweden, including the Stockholm region, has favourable geological conditions for building underground facilities and a long tradition of subsurface engineering. Despite these advantages, Stockholm lacks a comprehensive, long-term underground plan or strategy. For years, major subsurface projects have been driven by short-term needs, potentially hindering the optimal use of space below the cityscape. The overall purpose of this paper is twofold. First, we explore the nascent area of scholarly work concerned with the case of Stockholm’s subsurface. We do so by evaluating the current status and potential of urban underground planning in Stockholm municipality. Second, we seek to advance existing planning knowledge and practices concerning Stockholm’s subsurface by identifying several distinct but interrelated gaps and challenges that impede the immediate integration of urban underground space into strategic decision-making for the future of underground planning in Stockholm. We suggest that further research is necessary in several key areas to facilitate the effectiveness and sustainability of long-term urban underground use and planning in Stockholm City and its metropolitan area.