Assessment of surface water quality: Case study of Oued Fez catchment areas (Morocco)

Under sustainable development conditions, water quality and quantity play a crucial role in meeting basic human needs. To meet the growing demand for water, surface water quality management is an important aspect. Consequently, water quality must be monitored and assessed via the use of innovative techniques, such as water quality index (SEQ-Water).For that purpose, water quality of Oued Fez catchment areas was evaluated according to Moroccan water quality guidelines by using the weighted quality index (SEQ-Water), physicochemical parameters, trace elements and bacteriological characterization. Five Sites were chosen after a diagnosis based on different criteria such as activity and density of population. These sites were Amont oued Fez (S1), Oued Fez (S2), Oued Ljawahir (S3), Oued Tgat (S4) and Oued Ain Smen (S5). Physicochemical quality was determined by evaluating Chemical Oxygen Demand (COD), total Kjeldhal nitrogen (NTK), suspended solids (SS), nitrates (NO3-), nitrites (NO2-), ammonium (NH4+), sulphates (SO42-), total phosphorus (TP) and trace elements (Cr, Cd, Cu, Ni, Co, Pb and Zn). Bacteriological analyses were carried out by testing enumeration of total coliforms (TC) and fecal coliforms (FC).Except Oued Ain Smen, physico-chemical parameters exceed by far the Moroccan standards of surface water quality. High concentrations of Se, Cd, Pb and As were detected. Fecal and total coliforms were also present at all sites, and varied from 1150 CF/100 mL to 100,000 CF/100 mL. All results were statistically validated with a p value