From Flood Risk Assessment to Blue-Green Infrastructure Evaluation in Urban Built Environments: A Holistic Workflow Definition

Urban areas face increasing flood risks due to climate change and urbanisation. A comprehensive approach is needed to assess flood vulnerability and enhance urban resilience. This study presents a holistic flood risk assessment workflow that integrates the assessment of blue-green infrastructure (BGI) as a mitigation strategy. The proposed methodology is developed within the framework of the CLIMRES project and consists of three key components: (i) flood vulnerability mapping, (ii) tactical flood management planning, and (iii) resilience-oriented recommendations for urban environments. The workflow uses the identification of flood-prone areas, measures to protect citizens and buildings, climate change projections, data collection and possible BGI measures to provide vital and clear information to stakeholders at district and building level. Two pilot studies: Ljubljana, Slovenia, and Senigallia, Italy - demonstrate the applicability of the approach in diverse urban settings with different environmental challenges. The pilot implementations provide critical insights into the integration of BGI in flood management, the role of real-time data processing, and the need for user-friendly decision support tools for stakeholders, including researchers, urban planners, and policy makers. The developed workflow is designed to be flexible and adaptable, allowing its application in different urban environments with varying levels of data availability and infrastructure complexity, thus ensuring its replicability in different urban contexts. The results highlight the need for flexible and scalable flood assessment frameworks that accommodate local conditions and data availability while supporting climate adaptation strategies. The workflow developed enhances the ability of decision makers to identify vulnerable areas, assess the impact of mitigation measures, and develop forward-looking flood resilience strategies.