Prioritization Blue-Green Infrastructure Strategies: Developing a Hybrid Quantitative Approach Model for Sustainable Urban Water Management

Blue-Green Infrastructure (BGI) is critical in protecting natural and cultural landscapes, managing urban water resources, and mitigating agricultural, urban, and industrial pressures. BGI aims to implement nature-based solutions across various scales, from planning to design, to reduce surface runoff and enable rainwater collection and reuse. This study focuses on Ayvali Creek in Bursa, a significant urban stream impacted by agricultural, residential, and industrial activities, along with inadequate technical infrastructure, degrading water quality and the natural landscape. This study aims to identify BGI solutions suitable for Ayvali Creek and formulate planning and design strategies for sustainable and effective rainfall management. The methodology of this study included a SWOT (Strengths-Weaknesses-Opportunities-Threats) analysis for identifying the current conditions of the study area and a multi-criteria decision-making (MCDM) method known as the best and worst method (BWM) conducted with experts and stakeholders to rank BGI strategies according to their priority. Among the main criteria and sub-criteria, the “water/soil” (0.41) and “land-use/land-cover” (0.32) criteria, which contribute to the overarching ecological protection criterion (0.71), emerged as the highest priority strategies for effective BGI solutions. This finding underscores the paramount importance of ecological protection for Ayvali Creek. The methods and results of this quantitative research can serve as a framework for BGI, offering insight into successful strategies for sustainable water resource and rainfall management, not only for the region under study but also for other developing countries facing similar challenges with their water resources.