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Non-hysteretic numerical codes are often used to design store-and-release (SR) cover systems. Hysteretic and non-hysteretic predictions were compared using field measurements with instrumented column tests, consisting of fine-grained SR material (phosphate limestone waste) with high hysteretic behavior (hysteretic ratio a parts per thousand 11) placed over a capillary break layer. Transient unsaturated water flow was then predicted using a one-dimensional code (HYDRUS-1D) under semi-arid climatic conditions over 1 year. Non-hysteretic simulation based on the main wetting curve of the SR material and hysteretic simulation were validated with the measured data. The compared results showed better agreement between measured and predicted values for non-hysteretic simulation during wet periods, whereas the hysteretic scenario showed better agreement with field measurements during dry periods. The influence of hysteresis effects on the complex transient unsaturated water flow of the tested scenarios and conditions is considered minor.