Water Study of Physical, Chemical and Heavy Metals Parameters in River Indus and its Tributaries, Sindh, Pakistan

Abstract

This study was conducted to investigate the water quality of the Indus river, Sindh, Pakistan. A total of 41 locations were selected along the Indus river and its tributaries for the collection of surface water samples. Twenty-one physico-chemical parameters and heavy metals were analyzed and the data were interpreted through different statistical techniques. In the current study, eleven parameters including iron, copper, zinc, electrical conductivity (EC), total dissolved solids (TDS), pH, potassium, sodium, nitrate, sulfate, and chloride with an average value 0.13 mg/L, 0.04 mg/L, 0.16 mg/L, 733 µS/L, 211.2 mg/L, 7.6, 8.9 mg/L, 107.4 mg/L, 8.01 mg/L, 102 mg/L, 140 mg/L respectively and were within permissible limits set by the World Health Organization (WHO) for drinking water. Whereas, average values of cadmium, mercury, lead, total alkalinity (TA), chemical oxygen demand (COD), total hardness (TH) and turbidity were found 0.004 mg/L, 0.007 mg/L, 0.02 mg/L, 920 mg/L, 103 mg/L, 262 mg/L and 186.2 NTU respectively, higher than permissible limits. Pearson correlation matrix and cluster analysis were used to understand similarities and differences between variables. The variation in the correlation of different parameters shows the complexity of the water quality.