Title : Impacts of the discharges of the oil refinery "SONATRACH" on the surface water of Oued Saf Saf Skikda (Algeria)

Water is one of the essential elements for sustainable development because of its importance in life. Without this element, life would be impossible because it has been a preponderant factor in any socio-economic activity since the dawn of humanity. The last decades are characterized by intense and galloping industrialization, which affects the north of Algeria in a general way. This study aims to experiment with a working protocol based on surface water sampling of Oued Saf Saf to establish water quality and databases related to water pollution in Algeria. In this context, the analysis of physico-chemical parameters such as T°, pH, EC, BOD5, NO-3, NO-2, Cl-, SS, and fatty oils is necessary along the entire length of Oued Saf Saf (upstream, center, and downstream), which is located in the North-East of Algeria in the wilaya of Skikda, in the wet period (January–2021). The results obtained show that at the level of the stations where the wastewater of the wilaya of Skikda and the industrial rejections of the oil refinery (SONATRACH) are discharged, the leaching of the excesses of the agricultural products of the plains of the study area leads to an increase in nitrates, nitrites, and chlorides content, as well as the hydrogen potential and electric conductivity. All these last ones lead to the contamination and the increase in the pollution of the waters of this wadi, which become polluted and require adequate treatment to be usable by the population.