Sustainable Urban River Space Transformations: An Interdisciplinary Spatial Agenda for Research and Practice

Riverfront regeneration increasingly features in current sustainable urban transformations worldwide. However, this phenomenon is not yet grasped in its full complexity, which challenges our understanding of what constitutes a sustainable transformation. In this paper, we argue that adopting a morphological approach that treats rivers and cities equally is essential for understanding urban river spaces and their transformations. Drawing on 17 worldwide cases of river space transformation, we identify recurring challenges and opportunities, including climate adaptation, land-use change, data availability, context sensitivity, and knowledge transfer. We inventory current methods, datasets, and tools to assess their suitability and sufficiency for answering current research questions and enabling new ones. We also posit that integrated and scalable approaches are needed to combine qualitative and quantitative methods, support cross-case comparison, and remain adaptable to local conditions. As a first foundational step towards local integrated and global cross-case analyses, we introduce urban river space delineation as the basis for comparable analysis and present rcrisp, an open-source tool for automated and scalable morphological delineation of urban river spaces. Finally, we emphasise that advancing this agenda requires community and capacity building across disciplines and sectors, so that methods and tools can be shared, refined and extended. By connecting cases, methods and communities, the paper calls for collective action to build a common language and evidence base for sustainable urban river space transformation.