Physicochemical Water Quality and Heavy Metal Pollution along the Maniyari River, Chhattisgarh, India

Abstract

This study investigates the physicochemical characteristics and heavy metal contamination of the Maniyari River in the Takhatpur region of Chhattisgarh, with the objective of assessing the extent of anthropogenic influence and ecological risk. Water samples were collected from three sites upstream (Lormi Pathar), midstream (Maadi Chok, Chelligahat road), and downstream (Badghat, Bathri Road) and analyzed for temperature, pH, electrical conductivity, turbidity, total solids, alkalinity, hardness, chloride, phosphate, nitrate, dissolved oxygen, biochemical oxygen demand, and chemical oxygen demand. Concentrations of Fe, Mn, Cu, Zn, Pb, and Cr were determined using Atomic Absorption Spectrophotometry. The results revealed pronounced spatial and seasonal variations, with elevated biochemical oxygen demand (up to 6.9 mg/L) and chemical oxygen demand (up to 68.5 mg/L) in downstream regions, indicating significant organic pollution. Heavy metal analysis showed that lead and chromium posed the greatest concern, with maximum concentrations reaching 0.11 mg/L and 0.18 mg/L, respectively. These values exceeded the WHO/BIS permissible limits by approximately 11-fold for Pb and 3.6-fold for Cr, particularly in the downstream stretch during the summer season. The observed correlations between physicochemical parameters and metal concentrations suggest that cumulative inputs from industrial effluents, domestic sewage, and agricultural runoff are significantly altering the river’s chemical balance. The study highlights the urgent need for periodic monitoring and effective pollution control strategies to mitigate heavy metal contamination and maintain the ecological integrity of the Maniyari River ecosystem.