ABSTRACT
In recent years the quality of river water has been affected due to anthropogenic, agricultural and industrial activities. These poses threat to human health and aquatic lives. This study was carried out to assess the water quality of the Osse River, Edo State, Nigeria. Sampling was carried for three months during the wet season on three stations (Station 1-3) upstream to downstream. A total of 23 physical and chemical parameters were measured and comparison made with FMEnv (2002). From this study, parameters such as air temperature (25.5 – 27.5 oC), flowrate (17.26 – 25.925cm/sec), depth (2.675 – 3.22 mg/l) transparency (0.5675 - 0.6125m), pH (7.00 – 7.10), turbidity, (1.2829 – 1.4653 NTU), DO (5.79 – 6.1 mg/l), BOD5 (3.23 – 3.57 mg/l), Na (5.05 – 5.1075 mg/l), K (3.092 – 3.1275 mg/l) and sulphate (5.964 – 6.7435 mg/l) showed no significant difference (P>0.05), while parameters such as, EC (181 uS/cm), TSS (16.4 – 18.75 mg/l), TS (106.4 – 109.25 mg/l), TDS (90 – 90.5 mg/l), alkalinity (26.35 – 27.5 mg/l), salinity (39.91 – 43.305 mg/l), Ca (10.2605 – 10.581 mg/l), and hardness (40.032
– 51.073 mg/l) showed high significant difference (P<0.001 and P<0.005). Mg (3.3065 – 3.6955 mg/l) and water temperature (23 – 25.5 oC) showed significance (P<0.05) or. Seasonal comparison for the measured parameters showed that parameters such as air temperature, flow rate, depth, pH, EC, TDS, TSS, TS, DO, BOD5, K, Ca, hardness, sulphate and nitrate were higher during the wet season compared to dry season, while the others showed higher values during the dry season. All the parameters measured were below the FMEnv maximum permissible limit. This study showed that the Osse River is not polluted.
