Physicochemical and Hydrogeological Characteristics of Water Obtained From Borehole and Rivers in Okada and Environs, Edo State, Nigeria

The consumption of unsafe water is detrimental to human health. It is therefore important to ascertain the quality and purity of water set out for drinking purpose. This paper therefore investigates the physicochemical and hydrogeological properties of water obtained from boreholes and rivers located at various sites in Okada town and environs, Edo State, Nigeria. The physicochemical parameters were analyzed using standard methods. Results obtained for the physicochemical properties showed that the concentration of phosphate, sulphates, nitrates and manganese in the samples range between (0.0310-0.450) mg/L, (0.05-1.01) mg/L, (0.021-1.0) mg/L and (0.01-0.41) mg/L respectively. The maximum concentration of calcium and sodium in all the samples analyzed was 1.27 mg/L and 8.65mg/L. Comparison of the pH value of the samples shows they are all acidic in nature, with pH values which ranges from (4.3 – 6.0). In all the samples analyzed, it was observed that no trace of heavy metal (lead) was found except in Iguvinyoba River (down-stream) with a concentration of 0.001 mg/L. The biological oxygen demand (BOD) and chemical oxygen demand (COD) values from all the water samples are below the WHO standard while the dissolved oxygen (DO) values are above the WHO standard. The results revealed that physicochemical parameters were slightly below WHO and NAFDAC standards for drinking water, except for the high iron (Fe) content at Usen. Thus from established standard, the borehole and river water in the study area will need some treatment to render it suitable for drinking.

Keywords
physicochemical; hydrogeological properties; quality; drinking purpose; borehole; river water