Water pollution scenario at river uramurukwa flowing through owerri metropolis, Imo state, Nigeria
Verla Andrew Wirnkor, Verla Evelyn Ngozi, Amaobi Collins Emeka, Enyoh Christian Ebere
Pollution scenario of water from River Uramurukwa was investigated. In both rainy and dry season, 5 water samples each taken from different points were analysed to determine physico-chemical parameters and heavy metals (using Atomic Absorption Spectrophotometer). The investigated physico-chemical parameters for both dry and rainy season respectively ranges from: temperature (32-32.4oC, 29-29.8oC), electrical conductivity (15.67-2.00 µS/cm, 7.31-61 µS/cm), pH (5.2-5.7, 5.9-6.7), total dissolved solids (2.67-3.98 mg/L, 3.29-5.33 mg/L) and TSS (4.43-6.64 mg/L,4.88-5.84 mg/L). The analysed major ions were: sodium (Na+)(1.30-1.67 mg/L, 1.76-2.38 mg/L), potassium (K+)(0.819-0.898 mg/L, 0.08-1.89 mg/L), magnesium (Mg2+)(1.13-2.78 mg/L, 1.23-2.86 mg/L), calcium (Ca2+)(22.92-24.6 mg/L, 13.9-43.9 mg/L), nitrate (NO3-)(0.91-0.96 mg/L, 0.56-0.97 mg/L), phosphate (PO43-) (0.34-1.65 mg/L, 1.07-2.17 mg/L) and sulphate (SO42-)(23.4-24.8 mg/L, 21.02-29.18 mg/L). The investigated heavy metals were: lead (Pb), zinc (Zn)(1.2-2.63 mg/L, 1.60-3.33 mg/L), copper (Cu)(0.13-0.79 mg/L,0.001-0.61 mg/L), iron (Fe)(0.091-0.19 mg/L,0.017-1.97 mg/L), cadmium (Cd)(0.002-0.180 mg/L, 0.002-0.025 mg/L), manganese (Mn)(0.08-1.02 mg/L, 0.008-0.091 mg/L). Temperature, Ec, DO, TDS and TSS were found to compile with WHO guidelines for domestic drinking water except for pH. Cu, Mn, Fe, in the water samples were all within the recommended guidelines of FEPA and WHO for domestic water use. High concentrations of Cd, Mn and Fe were observed at point 2 while all points for Zn and Pb exhibited high concentration. Water quality Index showed the area is unpolluted and safe for use. No ecological risk was observed except for Cd and Pb. PLI was all within recommended limit except for point 2 during the dry season. It should be observed that the River is polluted with Cd and Pb, this are highly toxic metals which can cause serious health damages even at low concentration.