GIS-based framework for assessing priority locations for blue-green infrastructure implementation in urban areas

• The GIS-based method to identify suitable locations for BGI has been developed. • The method uses: land use, imperviousness, building height and density, exclusions. • The method supports planning in medium-sized cities facing rapid urban change. Progressing urbanization has significantly altered urban landscapes, leading to changes in land use and the structure of surface permeability. This study introduces a novel Geographic Information System (GIS)-based framework for assessing spatial changes and identifying priority locations for the implementation of blue-green infrastructure (BGI). We have developed the LUSIA (Land Use Indicator Analysis) method, employing user-defined mathematical algorithms in Python to compute five indicators: I_LU (Land Use), I_IMP (Imperviousness), I_BH (Building Height), I_BD (Building Density), and I_EX (Low-priority Areas). These indicators aim to delineate essential characteristics of land use patterns, sealing density, building density, and areas excluded from development. Applied to Olsztyn, NE Poland, LUSIA proved its capacity to identify short-term shifts in the urban landscape conducive to BGI application. The analysis highlighted a reduction in surface permeability driven by urban expansion from 2006 to 2018. Advocating for the integration of BGI solutions—such as rain gardens, green roofs, green walls, and permeable pavements—to bolster urban resilience, LUSIA identified prime locations for deploying specific BGI components. The findings suggest that BGI implementation could potentially “unseal” and green about 23% of the Olsztyn area, especially within residential zones. Our research indicates that strategic BGI placement can markedly aid in stormwater management, biodiversity enhancement, and the overall improvement of urban life quality. This study emphasizes the critical role of sustainable urban planning in mitigating the impacts of climate change and ongoing urbanization.