Assessment and characterization of groundwater quality under domestic distribution using hydrochemical and multivariate statistical methods in Bafia, Cameroon

Abstract

The best knowledge of physico-geochemical content of water helps to cope with adequacy between water availability and its importance. Thus, in BAFIA where groundwater is used in households, it is mandatory to evaluate and characterize the quality of that water. BAFIA is an important area of Cameroon due to its geographical position, growing population and associated needs. Located between an equatorial climate in the western region and a humid tropical climate in the eastern region, this area contains an aquifer system that represents sequences of shales, mica quarry, biotite gneiss, post-tectonic granites, and ortho-amphibolite. Groundwater flows aquifers recharge areas and provides base flows to supply drinking water to study area. The objective of this work was to assess the physicochemical and bacteriological quality of groundwater, to explain the phenomena that cause its mineralization in and around the BAFIA area and to correlate these different ions. We only included boreholes that had a good flow rate to meet the need to supply a large number of populations with water for domestic use. We conducted an analytical study of the physicochemical and bacteriological parameters of the elements collected from the water samples. The results were processed using hydro-chemical methods (Piper diagram, distribution maps of chemical elements) for a study of water typology and multivariate statistical analysis techniques. Principal component analysis (PCR) and ascending hierarchical classification (CHA) analysis were used to determine the phenomena causing water mineralization and the links between these waters, respectively. Our results showed that: the waters analyzed in the study area were slightly basic and moderately mineralized. Chemical parameter grades were below the world health organization (WHO) standard; except for iron. Most of the water was chlorinated and sulfated calsic and magnesic. Three phenomena have been at the origin of water mineralization: anthropogenic activity, recharge of groundwater (soil infiltration) and water-rock contact (main ion production mechanism).