Assessment of Physicochemical Parameters of Surface Water of Karnaphuli River in Bangladesh Towards Identification of Potential Sources

Abstract

In this study, water samples collected from Karnaphuli River, Chittagong, Bangladesh, were analyzed to assess physicochemical parameters to identify the possible potential sources of pollutants. Physicochemical parameters such as pH, alkalinity, acidity, conductivity, TDS, turbidity, total hardness, BOD, COD, ammoniacal-nitrogen, and sodium and chloride were varied from 3.05 to 9.34, 36.50 to 182.50 mg/L as CaCO₃, 0.00 to 78.00 mg/L as CaCO₃, 9.75 to 13.11 mS/cm, 6.36 to 10.40 g/L, 6.70 to 150.30 NTU, 1.37×10³ to 1.95×10³ mg/L as CaCO₃, 5.50 to 45.50 mg/L as O₂, 10.00 to 185.00 mg/L as O₂, 0.00 to 12.60 mg/L as NH3-N, 2.27×10³ to 2.92×10³ mg/L and 3.12×10³ to 4.60×10³ mg/L in the water samples, respectively. Acidity, TDS, turbidity, total hardness, BOD, COD, and sodium were all very high near the TSP fertilizer factory’s point source (site-2), while pH, alkalinity, NH₃-N, and chloride were very high at KAFCO (site-11). At site-11, BOD and COD levels were also elevated. The results indicate that untreated fertilizer effluents contaminated river water significantly. Pearson correlation matrix for physicochemical parameters and sodium and chloride was also calculated to confirm the potential sources of pollutants in the river water. TSP plant effluent has been shown to cause acidity, TDS, turbidity, BOD, COD and sodium in river water, whereas ammonia-urea plants are found to cause high pH, alkalinity, NH₃-N, as well as BOD and COD in the Karnaphuli River