Multivariate analysis of groundwater quality in parts of Lagos - Nigeria
AbstractThe quality of twenty-six groundwater sources in Lagos state was evaluated. Data on physico-chemical parameters (Hydrogen ion, Electrical Conductivity, Total Dissolve Solids, Calcium, Chloride, Total Hardness, Magnesium, Sodium, Potassium, Bicarbonate and Sulfate) were collated from the database of Lagos Water Corporation. The result shows
that all the parameters are within the maximum permissible limit of WHO, while Mg and HCO3 exceeded the SON limit of 0.2 and 3.0mg/L, respectively, for drinking water. The co-efficient of variation shows that all the groundwater parameters examined are highly variable except pH (10.92%).The factor analysis employed indicates that of the two Factors I and II, Factor I, which explains 62.73% of the total variance, has a strong positive loading on EC, TDS, TH, Na, Cl, Ca, K and SO4 . Factor II explains 17.43% of the total variance and has a strong positive loading on pH and
HCO3. The computed WQI value ranges from 1.41 to 261.48. The high value of WQI at these sampling locations has been found to be mainly from the higher values of TH, pH, TDS, Cl and Ca in the study area. The study demonstrates the effectiveness of factor analysis and water quality index in evaluating the hydrochemical processes of groundwater and the determination of the suitability of groundwater for drinking purpose, respectively, in the study area.