eng Science and Education Publishing American Journal of Water Resources 2333-4819 2026-02-04 14 1 27 31 10.12691/ajwr-14-1-4 AJWR20261414 article Assessment of Water Quality from the Mani River, the Water Source of the Yalenzou Water Supply System in N'Zérékoré Prefecture, Guinea Richard Adande adanderich@gmail.com 1 2 3 Michel Mathurin Kamdem 4 5 Herman L¨¦once Zinsou 5 Mamadouba Sylla 5 Lancei Koivogui 5 Aboubacar Ciss¨¦ 5 Oumar Alpha Bald¨¦ 6 Edmond Sossoukp¨¨ 6 Department of Hydrology, Faculty of Science and Technique, University of N¡¯Z¨¦r¨¦kor¨¦, P.O Box 50, N'Z¨¦r¨¦kor¨¦, Guinea Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of the Free State, Private Bag ¡Á13, Phuthaditjhaba 9866, South Africa Department de Mathematiques, Centre Universitaire de Z¨¦r¨¦kor¨¦, BP: 50, N¡¯Z¨¦r¨¦kor¨¦, Guinea High concentrations of chemical elements and bacteria (enteropathogenic bacteria) in water can cause waterborne diseases that are potentially dangerous to humans without prior effective treatment. The aim of this study was to evaluate the physico-chemical and bacteriological quality of the water from the Mani River and the Yalenzou water supply system in order to establish the occasional presence of contaminants. Water was sampled from March to May 2025 (towards the end of the dry season and the beginning of the rainy season), which corresponds to the increase in surface water. Results showed significant differences (P<0.05) in conductivity, total dissolved solids (TDS), salinity and biological oxygen demand (BOD5) among the two sampling sites. Mani River recorded the highest mean value of BOD5 (191.33±1.52 mg/L versus 189±3.00 mg/L). Fecal coliforms in the Mani River and raw water of Yalenzou water supply system were 332.33±17.61 and 165±5.00 CFU/100mL respectively. These values were far above the minimum standards set by the World Health Organization (3 coliforms/100 mL of water). Iron, turbidity, nitrite, temperature and salinity characterized the raw water from the water supply system, whereas conductivity, turbidity, salinity, BOD5, fecal and total coliforms characterized water from the Mani River. This study highlights the level of contamination of the Mani River and the questionable quality of water consume in households of the forest region, Guinea. https://pubs.sciepub.com/ajwr/14/1/4/ajwr-14-1-4.pdf Water quality physico-chemical characteristics fecal coliform Mani River N'Z¨¦r¨¦kor¨¦