Within the framework of meeting one of its mandates related to water quality monitoring, the Rwanda Water and Forestry Authority (RWFA) has commissioned a study aiming at establishing water quality baseline of some selected 36 water bodies in Rwanda. The study was conducted at the nine catchment level one. A set of sixteen (16) parameters were selected for this monitoring activity for each sampling site. These are: Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), Potential in Hydrogen (pH), Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Turbidity, Chloride (Cl^-), Sulfate (SO₄^2-), Nitrate (NO₃^-), Total nitrogen (TN), Total Phosphorus (TP), Total Dissolved Inorganic Nitrogen (DIN), Total Dissolved Inorganic Phosphorous (DIP), Faecal coliform (F.C) and Escherishia coli (E.coli).