Plunging water jets are used for oxygenation purposes due to their inherent advantages such as simplicity, energy efficiency, and low operational cost. Specifically, these provide an efficient gas-liquid interfacial area for dissolving oxygen in water. Oxygen transfer by plunging jets into stagnant water has received considerable attention; however, the oxygenation capacity of plunging water jets discharging into turbulent cross-flow has received limited attention. The flow characteristics such as volumetric oxygen transfer coefficient and standard oxygen transfer efficiency are evaluated considering water jet to cross-flow velocity ratio, jet fall height, cross-flow depth, and jet impact angle. Two equations are proposed for estimating the oxygen transfer rate for a single plunging jet in a turbulent cross-flow. Moreover, the dynamic behavior of the resulting two-phase air-water flow is investigated with the aid of flow visualization. (C) 2017 American Society of Civil Engineers.