TITLE:
Physicochemical and Bacteriological Characterization of Drinking Water Points in Urban Areas of Kandi, Northern Benin
AUTHORS:
Zawdjatou Tahirou, Roufaï B. Djibril, Sissou Zakari, Henri Sourou Totin Vodounon, Irénikatché P. B. Akponikpe
KEYWORDS:
Kandi, Water Quality, Water Quality Index, Hydrogeochemical Processes, Chemical Composition
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.17 No.4,
April
23,
2025
ABSTRACT: Freshwater constitutes only 2% of the world’s water resources, and its quality has been compromised by anthropogenic pollution and natural contamination. This research aims to appreciate the physicochemical and bacteriological quality of various drinking water sources in the city of Kandi. Thirty water samples were collected from wells, boreholes (private and public), and the national water distribution network of Benin (SONEB). Six microbiological parameters and 19 physicochemical parameters were analyzed. The Water Quality Index (WQI) was calculated based on 11 physicochemical parameters. Hydrochemical processes were examined using Piper and Gibbs diagrams. Contamination was found in 100% of the well water samples for the six microbiological parameters; only two microbiological parameters were detected in 40% of the borehole samples and 40% of the SONEB samples. Turbidity, potassium, iron, and nitrates exceeded WHO standards in 50%, 80%, 20%, and 65% of well water samples, respectively. The temperature of all water sources was above the normal standard. The WQI was rated as excellent for 100% of the borehole water samples in dry season and for 80% in rainy season. In contrast, the WQI was poor and very poor for well water samples (50% and 5%, respectively, in dry season; and 55% and 20%, respectively, in rainy season). Piper’s diagram showed heterogeneity in water type: bicarbonate calcium and magnesium facies (Ca2+-Mg2+-HCO3−) occurred in 40% and 28% during the dry and rainy seasons, respectively; chloride sulfate calcium and magnesium facies (Ca2+-Mg2+-Cl−-SO42−) in 28% and 32%; chloride sodium and potassium or sulfate sodium facies (Na+-K+-Cl−-SO42−) in 20% and 12%; and bicarbonate sodium and potassium facies (Na+-K+-HCO3−) in 12% and 28%. Lastly, the Gibbs diagram indicates that water-rock interactions and rock weathering were the primary factors influencing the chemical composition in the Kandi area. The results could help control sources of pollution in the city’s drinking water.