Spatial and Temporal Variation of Faecal Indicator Bacteria in Three Reservoirs of Ivory Coast (Taabo, Kossou, and Fae)

Abstract

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 × 10 0 to 1.53 × 10 4 CFU E. coli.100 mL-1 ; 10 × 10 0 to 2.67 × 10 3 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.

Trophic diversity and ecological balance of ichtyofauna in three lentic ecosystems of Côte d’Ivoire: Kossou, Taabo and Faé Lakes

“…That reflects ecosystems in ripe age and less disturbed (Frontier and Pichod-Viale, 1991;Surya et al, 2018). These results are consistent with those of Aka (2020), Camara (2023) and Tiémoko et al (2020) who asserted that although eutrophic, Kossou, Taabo and Faé lakes are still less disturbed.…”

“…Invasive aquatic plants are present and occupy a large part of the surface of different water bodies (Tiémoko et al, 2020).…”