Bechar, a typical Saharan city with an arid climate, receives an average annual rainfall of around 72 mm. Two resources ensure the supply of drinking water to the city of Bechar; the first comes from a catchment field consisting of eight boreholes, and the second comes from the Djorf Torba dam located in the west at about 45 km where is located the drinking water treatment plant. Water scarcity and water supply disruption have caused residents of Bechar city connected to the water supply system to invest in relatively expensive storage and pumping facilities to meet their domestic needs. The survey was conducted on a sample of 20% of the population of Bechar city in a period of 4 months. Through the survey, we have reached that 74% of citizens of Bechar city are not satisfied with the quality and quantity of water and 59% of respondents are not satisfied with the water pressure and are therefore forced to use the pumps.

In arid areas, the pressure on water resources and in particular on groundwater resources is on the rise, mainly due to increasing demand and the deterioration of water quality. In this context, the present work aims to follow the annual evolution, between 2009 and 2019 of the physicochemical parameters, and to evaluate the quality of groundwater of the region of Mougheul, by determining the data of pH, TDS, conductivity and the concentrations of major ions ( Ca+2, Mg+2, Na+, K+, Cl−, HCO3−, SO4−2, NO3−) of 07 water points. The results revealed that all the levels of the physicochemical parameters do not exceed the WHO potability standards, except high values were observed at the level of well W6 which exceeds the limits recommended by the WHO (50 mg /l). The diagram of Schöeller and Berkaloff shows that the groundwater has the bicarbonate magnesium facies. The representation of the data on the Piper triangular diagram shows that W6 has the facies chlorinated and calcium sulfate and magnesium and the other water points have the facies bicarbonate calcium and magnesium. SAR values show that the groundwater of Mougheul is excellent for irrigation. The classification according to the Wilcox diagram shows that the groundwater of Mougheul in general is good quality, but the well of W6 water is suitable for irrigation and requires monitoring the evolution of salinity.

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The conservation of natural non-renewable water resources is an important part of the expectations of the Algerian population, especially in the south of the country. Groundwater is provided in the southwest of Algeria, and the demand for water is high including agriculture. Studies have shown that the quality of these resources has changed after many years of continuous exploitation. To meet the satisfaction and the need for drinking water, for the city of Bechar, located in southwest Algeria, technicians and decision-makers have sought additional water resources, namely in the Jurassic groundwater located at the region of Mougheul (Sahara Algerian). The intense use of pumping at Mougheul has led to serious local problems (rapid drawdown and drying up of the source). The obtained results reveal that the piezometric charts, established in October 2001 and November 2009, show that the main flow of water is from north to south, exactly to the source of Mougheul. The flow rates of the drillings made are very varied, and between 6 and 30 l/s, this amounts to the heterogeneity of the medium. The pumping tests give low transmissivity values varying between 3.22 10–5 and 5.49 10−3 m2/s.