Abstract:
This study investigated the effects of effluent discharged from Warri Refinery on the
water quality of Ubeji River, Warri Delta state. Water samples were collected from
upstream, point of discharge of effluent and downstream sections of the river.
Physicochemical parameters (turbidity, pH, electrical conductivity, total dissolved
solid, total suspended solid, turbidity, dissolved oxygen, biological oxygen demand,
chemical oxygen demand, oil and grease), concentrations of polycyclic aromatic
hydrocarbons (PAHS) and heavy metals (Arsenic, Cadmium, Chromium, Nickel,
Lead and Zinc) of the receiving water body were determined and compared with the
WHO standard for drinking water. At the upstream section of the river, some
parameters were higher than WHO standard and these parameters are turbidity, oil and
grease, H2S, Chromium, Lead with the mean values 30.5±0.77, 6.96±1.11, 0.64±0.10,
0.039±0.00, 0.005±0.00 respectively. At the point of discharge, pH, TSS, BOD,
Chromium, Lead with mean values 6.7±0.08, 48.12±0.28, 12.56±0.34, 0.023±0.00,
0.004±0.00 respectively where found to be above WHO standard. At the downstream
section, EC (590.68±2.27), TSS (35.11±0.69), Turbidity (43.22±0.48), DO
(51.45±0.04), oil and grease (8.58±0.29), Phenol (5.99±0.03), H2S (0.58±0.01) and
Chromium (0.041±0.00), Lead (0.005±0.00) were found to be higher than WHO limit
for drinking water. PAHs were found to be higher than the WHO standard at the point
of discharge and downstream sections of the river. The concentration of these
pollutants indicated that the River is polluted and not good for human consumption. It
is therefore recommended that there should be continuous monitoring of refinery
effluent.
