Physico-chemical and bacteriological characteristics of groundwater in peri-urban areas of Cameroon, Central Africa: towards a new water management strategy including human-water interface

Three distinct localities experiencing different dynamics in peri-urban zones where there is coexistence of significant demographic growth, intense agricultural activity and absence of drinking water supply for populations have been investigated. In these sites, the populations rely informally on groundwater and rivers to meet their daily needs. Based on physicochemical and bacteriological parameters (electrical conductivity, pH, temperature, total dissolved solids, Ca²⁺, K⁺, Mg²⁺, Na⁺, NH₄⁺, Cl⁻, HCO₃⁻, NO₃⁻, SO₄²⁻, Escherichia coli and Salmonella typhi), this study aims to evaluate the origin of mineralization of these waters and their quality for human consumption. Results show that the water sources are weakly mineralized and acidic. The mineralization is controlled by alteration of silicates. In addition, the mineralization is also influenced by anthropogenic factors, supported by several indices, namely detection of bacteria in all water types, NH₄⁺ concentrations above those expected for natural aerobic groundwater and surface water (< 0.2 mg.L⁻¹) and high variability of facies from one water type to another and from one season to another. Based on the Water Quality Index, water resources are unsuitable for human consumption. This is affirmed by the presence of bacteria in all water samples and high content of NO₃⁻ above World Health Organization standards.