Towards Holistic, Multifunctional and Sustainable Stormwater Management: making Sense of Criteria, Indicators, and Evidence for Stormwater Decisions in Existing Urban Areas

Cities are shifting toward holistic, multifunctional, and sustainable stormwater management (SSWM), increasingly relying on nature-based solutions (NbS) that retain, convey, infiltrate, and treat water while delivering ecological quality, public value, and climate resilience. Given that NbS are spatially distributed and institutionally shared, their long-term delivery depends not only on hydrological performance but also on governance arrangements, including responsibilities, mandates, ownership, and maintenance, that shape legitimacy and outcomes. Critical challenges arise early, when goals are translated into criteria, indicators, and evidence that can be justified and used in planning and implementation.This thesis examines that decision space through a sequential mixed-methods design. It traces how governance and other long-term delivery conditions are (1) represented in global decision-support tools, (2) articulated by practitioners as decisive factors in two Swedish cities, and (3) operationalized as context-anchored indicator prompts in two contrasting catchments. The findings reveal a persistent asymmetry: technical evidence is often rendered decision-ready, whereas governance and context-sensitive conditions remain under-specified, even though they are central to achieving holistic, multifunctional SSWM.The thesis responds by applying a governance-aware sense-making step that makes these “silent” conditions and their assessability explicit. This approach provides a transparent basis for early-stage justification and for prioritizing what evidence is available now, what requires resourcing, and what demands coordination or mandate changes. By bridging technical evidence with institutional feasibility in early-stage assessment, the work supports more defensible decisions and more calibrated decision confidence for SSWM in existing urban areas.