The Moroccan Mediterranean Coastline: A Potential Threatened by the Urban Discharges

摘要

The Mediterranean coastline of Morocco is an exceptional and ecologically fragile marine area. It ischaracterized by a large diversity of living aquatic resources, and subjected to pollution, originated by industrial activities,domestic discharges, coastal touristic installations, etc., drown through drainage channels, emissaries, rivers, etc. Theimpact of this pollution on the hydraulic network and consequently on the coast, is harmful and may involve water qualitydegradation. The pollutant discharges to the Mediterranean coast is very high. The effluents generated by Tangier sea portand iseveral rivers such as Mghogha, Souani, Lihoud, F’nideq, and Martil can be considered as important pollutionsources based on its anoxic and reductive potential, the low dissolved oxygen contents and high oxydable matter rates.The performed study showed that Tangier and Tetouan marine areas are the two highest affected areas in theMediterranean coastline of Morocco. More than 232 tons/day (t/d) of SS are discharged in their coast. The total oxydablematters drained to the sea exceed 100 t/d. The total hydrocarbons spilled in coast is estimated to be higher than 5.15 kg/d.Metal pollution is also important and caused by high load of, among others, lead, cadmium, chromium, and nickel,exceeding the standards in some locations. Daily drained quantities of these heavy metals to the coast are estimated to be23.15 kg/d for Pb, 12.65 kg/d for Cd, 10.85 kg/d for Cr, 17.45 kg/d for Ni, 21.50 kg/d for Cu and 47.50 kg/d for Zn. Thissituation could be related to the importance of size of Tangier and Tetouan cities; which together represent about 75% ofthe total population of Moroccan Mediterranean coastline, and contain more than 75% of the industrial facilities. Thesetwo cities generate a total wastewater volume of 130,500 m3 /d, representing about 70% of the total wastewater volumeproduced by all the Moroccan Mediterranean cities.The situation becomes more critical if we consider the important occurrence of commercial traffic. Impacts are potentiallyrelated with deterioration of coastal degradation, of the quality of its resources. In view to preserve the marineenvironment and to ensure the sustainability of its natural health, Morocco is trying hard to translate gradually itsinternational commitments in national legislation level. This effort is further required that these engagements haveinvolved in specific programs participation, particularly in the Mediterranean. These programs often result in theimplementation of resolutions or recommendations targeted to complete a rigorous policy of sustainable development ofmarine coastal environment.