This study assessed the efficiencies of removing constituents of emerging concern (CECs) with ozone and ozone in combination with hydrogen peroxide in a bench‐scale flow‐through system designed to predict full‐scale removals. Five CECs were selected for evaluation: atrazine, caffeine, carbamazepine, primidone, and tris (2‐chloroethyl) phosphate. Two modeling compounds, 2‐methylisoborneol and geosmin, were used to establish bench‐scale operating conditions that mimicked previous pilot‐ and demonstration‐scale removals. The study demonstrated that CEC removal efficiencies in bench‐scale systems are generally consistent with removals in full‐scale systems. Thus, the bench‐scale system can be used to predict full‐scale removals. Additionally, bench‐scale results showed that CEC removal efficiencies were generally higher in State Project water (SPW) than in Colorado River water (CRW) or the SPW/CRW blend. These results were likely a consequence of the rapid formation of hydroxyl radicals in SPW.