Groundwater quality in the Zurbatiyah sub-district, eastern Iraq, was assessed using the Arithmetic Water Quality Index (AWQI) and the Canadian Water Quality Index (CCME-WQI). Field data were collected from six wells over a five-month period, and twelve physico-chemical parameters were analyzed. AWQI scores ranged from 5.46 to 84.77, classifying water quality from “Excellent” to “Poor”, depending on the well and season. In contrast, CCME-WQI scores ranged from 49.5 to 58.6, with all wells classified under the “Marginal” category, indicating frequent exceedances of permissible limits. The findings reflect high spatial and temporal variability, with parameters such as EC (1,750–6,120 µS/cm) and TDS (805–4,590 mg/L) often exceeding national and international guidelines. These results suggest moderate to severe salinization, particularly during peak irrigation months. Overall, CCME-WQI was found to provide a more conservative and realistic assessment of water quality risk, while AWQI tended to overestimate quality under certain seasonal conditions. The study highlights the need for continuous groundwater monitoring and sustainable water management in semi-arid regions. Based on Iraqi and FAO standards, none of the wells were suitable for drinking, while only two were deemed conditionally suitable for irrigation purposes.