Introduction: The consequences of rapid urbanization and the expansion of impervious surfaces include disruption of the natural hydrological cycle, increased flash floods, the development and intensification of urban heat islands, pollution of water and air resources, loss of biodiversity, and a decline in urban functional indicators. With the ever-growing population in urban areas, the concept of green infrastructure has emerged as a new approach in civil engineering and urban management. This approach seeks to combine natural spaces and engineered structures to simultaneously meet infrastructural needs while preserving ecosystem functions. Given the high potential of this approach, this paper aims to develop an practical framework for semi-arid regions by integrating the findings of a comprehensive land use planning study in West Azerbaijan Province with green infrastructure design principles.
Materials and Methods: This research, emphasizing spatial analysis based on official land use planning documents, combines engineering perspectives (structural design, hydrology, environmental management) with spatial planning. The case study focuses on West Azerbaijan Province, which faces challenges including the Urmia Lake crisis, spatial-economic imbalances, uneven urban growth, and corridor isolation. The land use planning analysis systematically evaluates spatial structure, settlement distribution patterns, water resource status, land use conflicts, and technical components of green infrastructure including permeable surfaces, rain gardens, green roofs, and artificial aquifers. Each component has been assessed for implementability in the province's semi-arid climate, characterized by water resource limitations and regional characteristics.
Results: The land use planning analysis reveals that the province's spatial structure, influenced by topography and hydrographic networks, has led to the concentration of settlements in fertile plains and overexploitation of groundwater resources, with critical deficits in the Khoy plain (11 MCM), Urmia, and Miandoab. The province suffers from low economic equilibrium and corridor isolation, with two structural discontinuities dividing it into three zones: northern, central, and southern. Green infrastructure systems not only serve as replacements for gray infrastructure but also function as effective complements, enhancing urban resilience. Based on conceptual models and studies in similar climates, implementing a combination of rain gardens and permeable surfaces in critical sub-watersheds can reduce runoff volume significantly. Adaptive solutions include using permeable surfaces with subsurface drainage in clayey soils, irrigating rain gardens with greywater, and using salt-tolerant plant species. International evidence shows runoff reduction of up to 88 percent (blue-green roofs) and peak flow reduction of up to 40 percent (permeable pavements).
Discussion: Spatial analysis reveals that green infrastructure serves distinct functions across the province's three zones: the northern and southern zones require connective interventions (green corridors and waterway restoration), while the central zone requires absorptive interventions (artificial aquifers, rain gardens, and permeable surfaces). This spatial differentiation represents a significant innovation in regional studies. Implementation challenges in Iran include institutional fragmentation, tender systems based on lowest cost, water stress, and weak social capital. Since green infrastructure as a decentralized system depends on continuous citizen cooperation, the proposed strategic framework combines four dimensions: institutional integration with social participation, efficient water management, context-based design, and continuous monitoring with IoT. In this regard, policy recommendations may include establishing a joint technical committee at the provincial level, implementing pilot projects, educational reform, and launching participatory campaigns.