GIS-BASED PEDESTRIAN ACCESSIBILITY ASSESSMENT IN TOD CATCHMENT AREAS: THE CASE OF KIM MA UNDERGROUND STATION, HANOI

Abstract

Pedestrian accessibility to public transport is not only a primary concern in urban planning but also a core element of the Transit-Oriented Development (TOD) model, which promotes public transit usage and reduces reliance on private vehicles. This study utilizes GIS-based network analysis to assess accessibility within the TOD catchment area of Kim Ma underground station in Ngoc Khanh Ward, Hanoi, Vietnam. The catchment area is defined within a 400–1200 m radius, corresponding to a 5–20 minute walk, in alignment with TOD principles and residential unit theories. The analysis reveals that effective accessibility within a 5-minute walk (400 m radius) accounts for only 55–60% of the theoretical TOD area, while accessibility within a 10-minute walk (800 m radius) reaches approximately 75–80%. This highlights a significant discrepancy between theoretical and actual accessibility. Field surveys indicate that these gaps stem from discontinuous pedestrian networks, widespread sidewalk encroachment, construction barriers, and traffic conflicts at major intersections, all of which increase actual walking time by approximately 1.0–1.3 times compared to ideal conditions. These findings demonstrate that GIS-based network analysis provides a more precise evaluation than traditional buffer-based methods, offering a robust scientific basis for TOD implementation at Kim Ma and other metro stations in Hanoi.