Impacts of Anthropogenic Activities on Water Quality of Ouangolodougou Dam, Côte d'Ivoire

The population growth, the expansion of villages and towns and several human activities put an increased pressure on water resources, leading to an exponential deterioration in the water quality of these resources. The main objective of the present study was to assess the impact of human activities on water quality of the Ouangolo dam. This study firstly investigated the characterization of water quality of the dam, through the analyses physicochemical parameters and determination of water quality and organic pollution indices. The sampling and analyses were carried out during rainy season in September 2021 and the second during dry season in January 2022. Then a survey was carried out in the dam’s environments in order to identify and localize human activities which are supposed to pollute the water of this resource. The results revealed the average values of following parameters: pH (6.9), electrical conductivity (124.83 µS/cm), iron (1,4 mg/L), arsenic (0,11 mg/L), BOD₅ (8,8 mg/L), NH₄⁺ (0,67 mg/L), pesticides POP (0.002 mg/L) and POH (0.001 mg/L). The water quality indice indicates values of 94.81 and 147.66 respectively for rainy and dry season, while organic pollution indice has values of 3 and 3.33 respectively for rainy and dry season. Results also showed that Agricultural practices in dam immediate perimeters are the main source of pollution (49%), followed by artisanal activities (27%) and households (24%). This study has shown that human activities (precisely agriculture) represent the most important source of pollution of the water from the dam of Ouangolo. It is thus important to raise awareness among the population around the dam on dangers about this situation.