STUDIES ON PHYSICO-CHEMICAL PARAMETERS OF A TROPICAL RIVER IN THE RAINY SEASON

Abstract

The physico-chemical parameters of Okhuiahe River, Nigeria were investigated during the rainy season months (May to October, 2011) to assess the water quality of the river. Samples were collected from four stations and a total of eighteen physico-chemical parameters were determined using standard methods. The mean concentrations of these parameters in the river ranged from 24.0oC – 26.3oC for air temperature, 21.7oC -24.0oC (water temperature), 24.3 – 37.4 CTU (colour), 84.4 – 146.3cm (transparency), 5.50 – 7.40 NTU (turbidity), 1.0 – 2.17mgl-1 (TSS), 11.8 – 14.4 mgl-1 (TDS), 13.33 – 15.36 mgl-1 (TS), 3.95 – 4.18 mgl-1 (DO), 3.18 – 3.86 mgl-1 (BOD5), 15.8 – 19.1?s/cm (conductivity), 6.35 – 6.50 (pH), 26.5 – 31.4 mgl-1 (chloride), 5.83 – 11.0 mgHCO3-1 (total hardness), 15.9 – 19.3mgl-1 (alkalinity), 0.73 – 1.87 mgl-1 (calcium), 0.97 – 2.02 mgl-1 (magnesium), 2.72 – 3.47mgl-1 (sulphate), 0.18 – 0.25 mgl-1 (nitrate) and 0.08 – 0.12mgl-1 (phosphate). With the exception of water temperature and transparency which were significantly different (P<0.05), all other physico-chemical parameters were not significantly different (P>0.05) in the study stations. The impact of anthropogenic activities on the water was insignificant as all parameters were homogenous across the study stations, and were under the maximum permissible levels of WHO guidelines for domestic usage.