Copper, lead, iron and manganese in the Sebou drainage basin; sources and impact on surface water quality

Water samples and samples of suspended solids (SS) were collected along the Sebou and its tributaries. Results of analyses of both dissolved and particle phase constituents revealed high levels of Cu (0.25 mg/L dissolved Cu, 0.55 mg/g particulate Cu), Pb (0.23 mg/L, 0.35 mg/g), Fe (27 mg/L, 50 mg/g) and Mn (2.5 mg/L, 1 mg/g) pollution in the basin. These results drew attention to the significant input from man-made sources (industry, farming, landfills). Comparison of Fe and Mn levels against Moroccan standards shows that the water in the basin is not appropriate for irrigation purposes. Conversely, Pb and Cu levels are below standard values. Concentrations of Fe, Mn and particularly Pb also make the waters in most areas of the basin unsuitable for the production of drinking water.