The reservoirs of Taabo, Kossou and Fae receive agricultural and domestic wastewaters which may impact their microbial quality, while the reservoir waters are used for fish farming, irrigation and other domestic purposes. This study aimed to evaluate the microbiological quality of these reservoirs by assessing the spatial and temporal distribution of the faecal indicator bacteria (FIB) abundances (Escherichia coli (E. coli) and Intestinal Enterococci (IE)). Thus, water samples were collected throughout a year at different sites of each reservoir. The FIB abundance (10 × 10⁰ to 1.53 × 10⁴ CFU E. coli.100 mL^-1; 10 × 10⁰ to 2.67 × 10³ CFU IE.100 mL^-1) were recorded, with high level values observed during the rainy season. The areas near the shore were more affected by faecal contamination than deepest areas due to the direct domestic wastewaters’ releases. According to EU directive, the 90^th percentile of the concentration of E. coli and IE in Taabo and Kossou reservoirs were lower than the level required for bathing indicating that the bathing could be possible. In contrast, the concentration of E. coli and IE in Fae reservoir were higher than the reference values, thus limiting uses of water for domestic purpose and irrigation and fish farming.

Keywords: Water Quality; Waste Water; Faecal Contamination; Reservoir;