Determination of Chemical Constituents and Trace Elements in Ground Drinking Water Around Chiro Town, West Hararghe, Ethiopia

This study evaluated the physicochemical quality of two drinking water samples collected from the Addis Ketema borewell and Arba Rakkatte, and designated as AK and AR, respectively, to evaluate their compliance with the World Health Organization (WHO) and Ethiopian Compulsory Standards (ECS) for potable water. Thirteen parameters were analyzed, including pH, total dissolved and suspended solids (TDS and TSS), chemical oxygen demand (COD), total hardness (TH), calcium (Ca), magnesium (Mg), alkalinity, and selected trace metals (Mn, Ni, Fe, and Zn). The results showed that the pH values (6.92–7.01) were within the permissible range, while TDS (470–560mg/L) and TSS (0mg/L) indicated good mineral balance. The COD values were zero, suggesting the absence of organic pollution. However, total hardness values (382.08–418.56mg/L) slightly exceeded the Ethiopian limit (300mg/L), primarily due to high calcium and magnesium concentrations. All trace metal concentrations (Mn, Ni, Fe, Zn) were well below permissible limits, indicating negligible contamination from metallic sources. Overall, both samples met the essential WHO and ECS requirements, except for hardness, which categorizes the water as <i>very hard</i> but not harmful to health. The findings confirm that the water is safe for drinking and household use; nevertheless, mild softening treatment is recommended to improve domestic suitability.