Spatial analysis of metro station areas in the Tehran using transit-oriented development (TOD) principles

Transit-oriented development (TOD) has become an influential concept in urban planning, aimed at fostering more sustainable urban environments through the integration of land use and transportation systems. TOD encourages higher density, and mixed-use development within walkable distances of public transport nodes, reducing reliance on private vehicles. In the context of rapidly expanding urban regions, this approach is particularly relevant. The Tehran metropolis—having experienced a population increase of nearly twentyfold over the past century—faces mounting challenges related to urban sprawl, unbalanced land use distribution, inefficient transportation systems, and increased intra-city travel distances. These dynamics highlight the urgent need for transit-integrated urban development models. This study investigates the spatial potential of TOD implementation across Tehran by focusing on the station areas surrounding public transport infrastructure. Unlike previous research, which often concentrates on isolated case studies of individual stations or lacks comprehensive classification, this study provides a citywide spatial assessment of TOD readiness. The primary objective is to evaluate the suitability of station catchment areas—defined by an 800-meter walkable distance—for TOD criteria and to classify these areas based on spatial and functional attributes. The methodological framework of the study centeres on the integration of spatial analysis with statistical modeling. Using Geographic Information Systems (GIS), 137 transit stations located within the municipal boundaries of Tehran were selected as the spatial units of analysis. A network-based service-area analysis was conducted to delineate the actual walking distance of 800 meters around each station, ensuring more accurate urban spatial representations than simple Euclidean buffers. Subsequently, a set of TOD-related indicators was measured within each station area. These indicators encompassed variables such as residential density, access to commercial centers, availability of urban services and infrastructure, connectivity to public transport modes, land-use mix, and the presence of green and open spaces. The data were compiled from multiple urban and transportation datasets and standardized for comparability across all station areas. To reduce dimensionality and uncover latent structures among the indicators, Exploratory Factor Analysis (EFA) was applied. This statistical technique enabled the identification of six principal components representing the core dimensions of TOD performance: (1) access to dense residential areas, (2) access to commercial/business centers, (3) availability of urban services and infrastructure, (4) proximity to other modes of public transport, (5) diversity of land uses, and (6) access to green and open space. Following the EFA, cluster analysis was employed to classify the 137 station areas into typologically distinct groups based on their factor scores. Six TOD station typologies were identified, reflecting varying degrees of readiness and potential for TOD-oriented transformation. These typologies capture the heterogeneity of Tehran’s urban form and transport integration, from highly connected and dense central areas to peripheral zones lacking critical TOD features. The analysis revealed that while certain clusters possess favorable conditions for TOD implementation, others fall significantly short of the minimum requirements, particularly in terms of mixed land use and connectivity. These findings underscore the necessity for differentiated planning strategies at both citywide and district levels. In areas with high TOD potential, policies should support mixed-use infill development and improved transit services. In less developed areas, foundational infrastructure and land-use rebalancing are essential preconditions for TOD success. By leveraging spatial and statistical methodologies in a complementary manner, this research offers a robust analytical framework for assessing TOD opportunities and challenges in large metropolitan regions. The results contribute to a broader understanding of how spatial typologies of station areas can inform transit-integrated urban development strategies, with specific implications for Tehran’s future urban and transportation planning agendas.