The research is aimed at assessing groundwater quality of Mayo Belwa area and environs for domestic purposes using multivariate techniques. A total of twelve water samples (seven from boreholes and five from hand-dug wells) were collected for physico-chemical and microbiological analysis. The sampled groundwater were analyzed for major cations: Na+, Ca2+, K+, Fe2+, Mg2+ and anions: Cl-, HCO3-, SO42- and CO32-. The order of abundance of the cations concentration is within the compositional order of Ca2+>Mg2+>K+ >Na+ while those of the anions are HCO3 ->Cl-CO32-. The important physical and chemical constituents influencing water quality for domestic purposes such as Temperature, pH, EC, TDS, Potassium (K+), Calcium (Ca2+), Sodium (Na+), Potassium (K+), Magnesium (Mg2+), Iron (Fe2+), Chloride (Cl-), Fluoride (F-), Sulphate (SO42-), Nitrate (NO3-) and total coliform count were assessed and compared with standard values. The values of Temperature (27.05 31), pH (4.22 6.2), EC (62 141.9 µs/cm), TDS (35.33 101 mg/l), TH (52.13 86.66 mg/l) were found to be within the safe limits and thus suitable for domestic purposes. Similarly, all chemical constituents except some of the coliform are within the WHO permissible standard. All the samples from boreholes falls within the allowable limit of 3.0 cfu whereas the hand-dug wells are slightly higher (4 6 cfu), with little effect on the people in the area. Four of the seven boreholes yielded Grade A WQI of 19.92 to 23.89, depicting an excellent water quality whereas the remaining boreholes and hand-dug wells recorded good quality water of grade B (25.87 43.12). Piper diagram classified the water in area as Ca2+ Mg2+ HCO3- facies, which typically of alkaline group. Multivariate statistical analysis identified salinity, leaching of bed rock, natural mineralization and rock-water interaction and redox reaction involving reduction of ferric ferrous iron as the processes that controls groundwater chemistry. Overall results indicates that the water is save for domestic purposes.
Key words: Groundwater quality; Water Quality Index, Multivariate Statistical Analysis; Mayo-Belwa
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