A GIS-based Method for Prioritizing Brownfields Transformation into Multifunctional Urban Green Infrastructure: The Case of Rouen Metropolitan Area, France

Abstract

Cities spatially expand as the global population increases. This brings significant environmental challenges and growing demand for enhanced residents’ well-being. The EU has therefore declared its policy of No Net Land Take by 2050, which France adopted in its national law with the policy “Zéro Artificialisation Nette” (ZAN). Both policies encourage the reuse of developed lands. In Rouen Metropolitan Area, more than 400 brownfield sites were identified (CEREMA, 2023), which is subject to regenerate brownfield measures. Influenced by the 19th-century industrial expansion of textile production, which took advantage of the hydraulic power provided by the rivers, the area experienced the emergence of brownfields after the closure of textile factories in the 1960s (Rouen Metropolitan Area, 2020). The aim of this study is to present a practical tool for decision-makers and researchers aimed at transforming brownfields into multifunctional urban green infrastructure. It involves moving beyond random allocation in green infrastructure planning and propose a systematic assessment of land suitability and urban demands to prioritize brownfield sites. In response, this study was conducted for the Rouen Metropolitan Area, France, using a GIS-based multi-criteria evaluation method to calculate the coupling coordination degree between site attributes and urban functional demands (Feng et al., 2023). Large volumes of spatial data and multiple criteria were assessed to rank the site suitability (Aburas et al., 2015). Furthermore, urban demands (Korkou, Tarigan and Hanslin, 2023), including local temperature regulation, flooding reduction, habitat connectivity improvement, and air purification, were taking into account to carry out spatial priority areas towards green infrastructure planning. According to obtained results, despite some sites displaying high value independently in either site suitability or urban functionality, the new approach identifies sites with a high coupling coordinate degree, indicating their high value in both site suitability analysis and multifunctional urban demands. Through this method, sites were categorized into high, medium and low priorities. This approach is in line with the principles of sustainable development, as the implementation of urban green infrastructure not only addresses various environmental challenges, but also provides significant social and territorial benefits. The presented GIS-based analysis technique can be used as part of a spatial planning process, applicable to any city that faces similar problems. It provides support to identify suitable areas for green infrastructure expansion.