The availability of adequate water in terms of quality and quantity is essential to human existence. Safe drinking water is vital for the general public's health. This study examined the physico-chemical parameters and the level of bacterial contamination in water samples randomly obtained from hand-dug wells in Ondo City, Southwest, Nigeria. The physicochemical parameters of the water samples were determined by standard methods. The concentrations of the metals were evaluated using an Atomic Absorption Spectrophotometer (AAS), and bacteria contamination was quantified via the membrane filtration method. The results of the physicochemical analysis showed that the temperature values ranged from 27.1 to 29.8 °C, and pH (6.1–7.8). The mean values of BOD (1.493 ± 0.17 mg/l), DO (7.088 ± 0.70 mg/l), total alkalinity (70.71 ± 14.72 mg/l), total hardness (77.06 ± 11.28 mg/l) and redox potential (615.8 ± 153.5 mV) were all within the limits of WHO guidelines for drinking water. However, the values of conductivity ranged from 0.07 to 1.26 uS/cm, TDS (59–907 mg/l); and the mean values obtained for COD (60.97 ± 12.16 mg/l), Ammonia (16.54 ± 10.85 mg/l), Nitrite (9.648 ± 1.25 mg/l), Nitrate (51.85 ± 6.25 mg/l), Fluoride (1.95 ± 0.49 mg/l), Chloride (19.74 ± 6.83 mg/l) and Manganese (0.2708 ± 0.12 mg/l) were all slightly above the set limit of WHO standard. The occurrence of metals is in order of Cu ˃ Cr ˃ Pb > Cd > As in positive water samples with Arsenic (14.63%), Cadmium (15.85%), Lead (19.51%), Chromium (20.73%), and Copper (29.28%). Arsenic, Cadmium, and Lead were slightly above the upper limit set by WHO in some sampling units. All water samples investigated were contaminated by microorganisms, and each water sample tested had at least one parameter above the benchmark limits, hence the poor quality of the water sources. The provision of potable pipe-borne water supplies to the population in the study area is therefore recommended.
Tiamiyu et al. (Wed,) studied this question.