Assessment of underground water quality in Okobo local government area of Akwa Ibom State, Nigeria

Abstract The ground water quality of Okobo Local Government Area was investigated. Sixteen boreholes (BHs) samples were collected from four zones (Okopedi, Ekeya, Ukwong and Okiuso) in Okobo. Standard analytical procedures used to analyze the physicochemical, bacteriological heavy metal parameters results compared Nigerian standard for drinking (NSDWQ). some physicochemical investigated within acceptable limits set by NSDWQ except pH (5.99 ± 0.37), DO (0.31 0.06) mg/L, BOD5 (6.26 0.4) mg/L Nitrate (62.53 5.96) mg/L. Bacteriological parameter like fecal coliform (128.69 31.40) MPN/100 mL total (287.63 40.31) also above implying organic pollution due contamination. Heavy metals limit Lead (0.1 0.1) Chromium (0.4 0.2) Manganese (0.16 which slightly all zones. Water index calculation grouped BHs into; BH7 (26–50) very good; BH1, BH3, BH4, BH8, BH11, BH14, BH16 (51–75) poor; BH2, BH5, BH6, BH9, BH12, BH13 BH15 (76–100) poor BH 10(> 100) unsuitable drinking. Pearson coefficient correlation, principal component analysis (PCA) cluster (CA) establish interrelationship among parameters, common sources pollutants grouping affected these pollutants. PCA extracted six components (PCs) BHs, with either natural mineral or anthropogenic source. CA sixteen into three clusters various levels contamination pollutant sources. Consequently, polluted require treatment using high test hypochlorite (HTH) as is mostly bacterial pollutant; moreover, should be sited 15 m away septic tank latrine reduce coliform.