This study explores using probabilistic and deterministic approaches for evaluating the quality of groundwater resources. The proposed methodology first used the probabilistic approach, which included multivariate statistical analysis, to classify the groundwater's physiochemical characteristics. Then, building on the obtained results, the deterministic approach, which included hydrochemistry analyses, was applied for comprehensive assessment of groundwater quality for different applications. To present this multidisciplinary approach, a basin located in an arid region was studied. Considering the results from correlation and principal component analyses, along with hierarchical Q-mode cluster analysis, chloride salts dissolution was identified within the aquifer. Further application of the deterministic approach revealed degradation of groundwater quality throughout the basin, possibly due to the saltwater intrusion. By developing the water quality index and a multi-hazard risk assessment methodology, the suitability of groundwater for human consumption and irrigation purposes was assessed. The obtained results were compared with two other studies conducted on aquifers under similar arid climate conditions. This comparison indicated that quality of groundwater resources within arid regions is prone to degradation from salinization. The combined consideration of probabilistic and deterministic approaches provided an effective means for comprehensive evaluation of groundwater quality across different aquifers or within one.