Assessment of Amuruto River Water Quality Using Weighted Arithmetic Water Quality Index (WAWQI), Rivers State, Nigeria

Water quality assessment is critical for monitoring environmental health, human safety, and aquatic life sustainability. This study evaluates the water quality of Amuruto River using the Weighted Arithmetic Water Quality Index (WAWQI) model for both wet and dry seasons. Various physicochemical and biological parameters were analyzed, and their impact on water quality was assessed. The wet season recorded a higher WAWQI score, indicating more severe pollution due to flooding and runoff, while the dry season showed increased chemical pollution due to reduced dilution. This study highlights the impact of agricultural runoff, petroleum spillages, timber processing, and sand mining on overall water quality. Results indicate a significant deterioration in water quality during the dry season, with a WAWQI of 27934.04, categorizing the river as "unsuitable for drinking." The wet season exhibited comparatively better conditions, with a WAWQI of 412.43, though still falling into the "very poor" category. Correlation analysis between individual parameters and overall water quality showed that Total Hydrocarbon Content (THC), TDS, Phosphates, Nitrates and Chemical Oxygen Demand (COD) were the most influential pollutants, due to anthropogenic activities and runoff and flooding. The findings emphasize the need for season-specific pollution control strategies. The strategies include industrial and domestic effluent control, wastewater treatment and public awareness, are recommended to restore water quality.