DOI: https://doi.org/10.36347/sajb.2025.v13i01.002

Pages: 11-20

This study evaluates the physicochemical state of the Kamagema River and the impact of human activities in its surrounding areas. Seasonal water samples were collected from three sites, selected based on local population activities. Physicochemical parameters were analyzed using standard methods, and the river's organic load was assessed through the Organic Pollution Index (OPI) by Leclercq and Marquet and the Interuniversity Laboratory for Education and Communication in Science (LISEC) index. The findings revealed spatial and seasonal variations in the physicochemical properties and pollution levels of the Kamagema River, with higher pollution levels observed during the rainy season (F=46.34; p<0.05). The pollution sources include domestic waste and effluents from the Hospital of Panzi located at Site 2. Principal Component Analysis (PCA) of the physicochemical parameters indicated significant differences among the three sites. The upstream site had the lowest sulfate concentrations, the middle site (Site 2) was characterized by moderate levels of alkalinity, phosphate, ammonium, and total phosphorus, while the downstream site showed higher levels of total hardness and magnesium hardness. The OPI values (3.1–3.4) indicated moderate organic pollution along the river, while the LISEC index (~10.5) showed moderate pollution at Sites 1 and 3 and heavy pollution at Site 2. The study recommends effective waste management along the Kamagema River to preserve its ecosystem.