GIS Mapping of Solid Waste Dumpsites in Port Harcourt Metropolis

Indiscriminate solid waste disposal poses significant environmental and public health risks in Port Harcourt, Rivers State. This study maps the spatial distribution of formal and informal solid waste dumpsites across Port Harcourt metropolis using GIS and high-resolution imagery from Google Earth. Field surveys using GPS devices geo-reference 214 waste disposal points, categorised by type (open dumpsite, controlled landfill, illegal roadside dump) and proximity to sensitive receptors including residential areas, water bodies, and schools. Spatial analysis examines clustering patterns using kernel density estimation and the Nearest Neighbour Index. Buffer analysis quantifies the population exposed within 500-metre risk zones around each site. Results reveal a high concentration of informal dumpsites in densely populated low-income communities including Diobu, Rumuola, and Mgbuoba. Only three formal disposal facilities serve the entire metropolis, reflecting a critical infrastructure deficit. The study recommends designating additional engineered landfill sites in peripheral zones identified through the spatial analysis. Findings are intended to support the Rivers State Waste Management Authority in developing a comprehensive waste infrastructure plan. Keywords: solid waste, GIS mapping, Port Harcourt, dumpsite, spatial distribution