Water quality appraisal of selected farm provinces using integrated hydrogeochemical, multivariate statistical, and microbiological technique

Abstract

With increasing use of agrochemicals, inorganic and organic fertilizers in the selected rural farm provinces in Nigeria, the need to assess the quality of their water resources for various purposes became compelling. This research, therefore, investigated the quality and geochemistry of groundwaters and surface waters in the area using integrated physicochemical, hydrogeochemical, multivariate statistical and microbiological approach. Most values from physicochemical analysis were generally below maximum allowable limits. However, some samples are contaminated, with some obtained parameter values beyond allowable limits. The pH, NO₃, NO₂, PO₄, K, and Mn values ranged from 4.1 to 6.9, 0–33 mg/l, 0–0.08 mg/l, 0–19.91 mg/l, 0–7.92 mg/l and 0–0.07 mg/l, respectively. Based on pH, many of the samples are slightly acidic. The dominant water type is Ca-HCO₃, with few Ca-Cl types. Hydrogeochemical investigations further showed that the supply of major ions in the waters and the geochemical evolution are mainly controlled by rock–water interactions, silicate weathering and ionic exchanges. However, multivariate statistical analyses showed that the variations in chemistry and quality of the waters are due to combined influences of geogenic processes and human activities. Microbial analysis revealed that many samples are contaminated with Escherichia coli, Klebsiella, Salmonella, Shigella and Staphylococcus species. Treatment of contaminated water before use is, therefore, advised.