Diagnostic of physicochemical and bacteriological quality of fez wastewaters rejected in Sebou River: Morocco

The high demographic growth of the city of Fez, as well as the implantation of social districts in the periphery of the city, is leading to the deterioration of water quality of the Sebou River. This critical situation has considerable effects on the environment of Fez, where this river has become in its vicinity a sewer leading to various nuisances. The total pollution added by the city rises to 100,000 m³/day, it will reach 120,000 m³/day by 2015. Sebou River represents the main superficial network of Fez region. It is threatened currently by human activities such as urban, industrial and agricultural wastes. To evaluate water quality of this river, a study was carried out to determine the physicochemical and bacteriological parameters during the two seasons: winter (November 2006) and summer (July 2007). Results show a high level of pollution from various sources notably by Fez industrial wastewaters. Downstream discharges of the city and downstream the point of confluence of Fez stream and Sebou River, we note a low content in dissolved oxygen; high contents in suspended matter, nitrites and DBO₅ and high conductivity, high concentrations in phosphates, sulphates and heavy metals (Cd, Hg, Cr, Cu and Zn). This study also presents an evaluation of the bacterial load in discharged wastewaters. The concentrations of fecal coliform and fecal streptococci bacteria exceed greatly the norms recommended by WHO.