Assessment of Groundwater Quality in a Selected Residential Area of Ibadan

Groundwater is a vital source of drinking water in Nigeria, particularly in peri-urban areas where public water supply is limited. This study evaluated groundwater quality in Awotan Asunle, Ibadan, for domestic use by analysing physicochemical parameters and selected heavy metals (Fe, Cu, Zn) from ten sampling points consisting of five wells (W1–W5) and five boreholes (B1–B5). Key parameters analysed included pH, turbidity, alkalinity, hardness, chloride, sulphate, dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand (COD), and the results were compared with standards established by the World Health Organization (WHO), Nigerian Standard for Drinking Water Quality (NSDWQ), and the European Union (EU).Most parameters were within permissible limits, indicating generally good water quality with minimal organic and metal contamination. Low turbidity confirmed effective natural filtration, while low BOD and COD suggested negligible organic pollution. Metal concentrations were below guideline values, indicating no significant health risk. However, pH values (5.65–6.65) revealed slightly acidic conditions that may corrode plumbing systems, and elevated chloride in one well suggested localized anthropogenic influence. Dissolved oxygen levels were generally acceptable with minor variations among sampling points. The study concludes that groundwater in Awotan Asunle is largely suitable for domestic use but remains vulnerable to localized contamination and acidity. Regular monitoring, improved sanitation, and appropriate treatment measures are recommended to safeguard water quality and support sustainable groundwater management in rapidly developing peri-urban communities.