Located in the southeastern region of Morocco, the Zagora area mainly relies on groundwater as a source of water supply. However, this groundwater is often of concern, due to the limited recharge and unfavorable geological conditions for the development of the aquifer. Despite this, private wells in the Zagora ditch reveal relatively rich water resources. Geochemical and isotopic studies were conducted in the area to understand the origin of the groundwater and its salinity, aiding in informed water management strategies to assist in better planning and regulation of well construction, as well as in mitigating the impacts of high salinity on local water supply and agricultural systems. The results show that the water quality varies, with some wells having conductivity values in excess of 5 mS/cm. Most groundwater samples have high salinity and low pH due to the CO₂ dissolved in groundwater. Geochemical analysis indicated two chemical facies: chloride–sulfate calcic/magnesic and bicarbonate calcic/magnesic. The presence of Na⁺ and Cl⁻ indicated that the origin of these two elements in these waters was the dissolution of halite, with some samples showing an enrichment of Na⁺ compared to Cl⁻. This could be attributed to cation exchange. The concentration of Ca²⁺ and HCO₃⁻ suggested that their origin is the dissolution of calcite and the weathering of calcium silicate minerals such as plagioclase. The isotopic analysis showed that the δ¹⁸O values ranged from −10.98‰ to −8.54‰, and δ²H values ranged from −75.9‰ to −62.3‰. This indicated that the groundwater originated from the High Atlas with a recharge altitude between 2600 m and 2800 m. The groundwater flows into the graben through fissures and regional fault networks.

In the Marrakech region of Morocco, where water resources are particularly limited, excessive salinity has been measured in the water from some wells intended for human consumption and irrigation. Moreover, the start-up of a mine for the exploitation of a polymetallic sulfide deposit and the progress of the exploitation work have revealed the existence of very saline deep groundwater with a total mineralization of over 80 g/L. The hydrogeochemical study using conservative elements has helped to understand the origin of the groundwater salinity in the Draa Sfar mine and to assess the contribution of the deep salinity source to the high salinities observed in the mine. The groundwater of the shallow aquifer shows almost constant Br⁻/Cl⁻ and Na⁺/Cl⁻ ratios, independent of the chloride content. The constant ratios of these conservative elements indicate a single autochthonous origin of Cl⁻, Br⁻ and Na⁺, and groundwater salinity is diluted by recharge water containing low concentrations of these elements. Regarding the mine groundwater, the high Li⁺/Cl⁻ ratio and Br⁻/Cl⁻ ratios in the range measured on the leachates of the rocks extracted from the mine indicate that the pore water is the reservoir for dissolved chloride and the salinity of the mine’s groundwater results from a mixture between these pore waters and fresh meteoric water that seeps in from the surface and recharges the entire aquifer. This porewater would be a remnant of the hydrothermal fluids that formed the sulfide deposit.

Groundwater management presents a challenge for open-cast phosphate mining within the Beni Amir deposit, Oulad Abdoun Basin, Morocco, where future mining operations are progressively reaching deeper saturated phosphate layers. This study integrates six Electrical Resistivity Tomography (ERT) profiles, eleven Magnetic Resonance Sounding (MRS) measurements, hydrostratigraphic modeling, 690 borehole logs, 580 piezometric measurements, and pumping-test results from 14 production wells to characterize the multilayer aquifer system. The comprehensive interpretation identifies three water-bearing zones: a shallow Eocene aquifer located within the Lutetian–Ypresian succession at depths approximately between 2 and 20 m, an intermediate Danian–Thanetian to Maastrichtian phosphate-bearing aquifer situated at depths ranging from 20 to 60 m, and a deeper Senonian marly limestone aquifer occurring below 60 m. Saturated zones are generally associated with low resistivity values, commonly below 28 Ω·m, and MRS-derived mobile water contents ranging from 0.3% to 4.4%. The hydraulic conductivity derived from MRS data exhibits a range of one and a half orders of magnitude across the majority of soundings, from 1.5 × 10⁻⁶ to 5 × 10⁻⁵ m/s. A comparative analysis with pumping tests shows that MRS-derived hydraulic conductivity is generally greater than well-test estimates, with localized discrepancies that may reflect scale effects, lithological heterogeneity, inversion uncertainties, and the necessity for localized calibration. As a working hypothesis, areas spatially associated with ephemeral streambed channels may represent potential zones of localized recharge or inflow, possibly where erosional truncation reduces the continuity of confining layers. The resultant hydrostratigraphic framework constrains saturated zones and hydraulic heterogeneity, thereby establishing a foundation for forthcoming groundwater flow modeling and mine dewatering evaluations.