Spatial pattern and environmental implications of automobile mechanic workshops in Birnin Kebbi metropolis, Nigeria using geographic information systems

This study employed Geographic Information System (GIS) techniques to examine the spatial distribution and proximity-based environmental risk of automobile mechanic workshops in Birnin Kebbi metropolis, Northwestern Nigeria. A census-based field survey was conducted, during which the geographic coordinates of 35 operational automobile mechanic workshops across five wards were captured using handheld GPS devices and complemented with secondary spatial data obtained from local planning authorities. Spatial analyses, including Nearest Neighbour Analysis (NNA), hotspot analysis, and buffer-based proximity assessment, were performed using ArcGIS software (version 10.7). The results indicate a statistically significant clustered spatial pattern of automobile mechanic workshops, with concentrations occurring along major transportation corridors and established service clusters such as Mechanic Village and the General Sani Abacha Bypass. In contrast, several wards exhibit low workshop density, reflecting the uneven spatial distribution of automobile repair services within the metropolis. Proximity analysis further reveals that approximately 49% of the identified workshops are located within a 30-m buffer of water sources, a distance commonly applied as a screening threshold in environmental risk assessments. Although this study does not measure contamination levels, the observed spatial overlap identifies locations where environmental monitoring and regulatory attention may be warranted. In general, the findings demonstrate the effectiveness of GIS-based spatial analysis for identifying service clustering, spatial inequality, and environmentally sensitive locations associated with informal automobile repair activities. The study recommends the integration of geospatial evidence into urban zoning and environmental regulation to support safer and more spatially organised vehicle servicing practices in Birnin Kebbi. The methodological framework presented offers a transferable approach for spatial assessment of informal urban service activities in comparable urban contexts.