The discharge of flows into a waterway, e.g. from industrial, power plants, and storm water collectors, may affect passing ships depending on the induced transverse momentum acting on a ship in front of an outfall structure. In this study, the effect of the angle of inclination of the outlet was investigated along with its opening angle, depth of water, and the magnitude of the velocity in a rectangular flume. Cross current velocities at the outlet of the introduction construction were measured and then compared by the designer, in which the maximum cross current velocities of the water introduction construction were estimated specially a state-of-the-art theoretical approach, to determine if that design was safe or not. The results are presented by curves and equations which can be used for the design of the water intruded construction to provide operational traffic safety for the passing ships in inland waterways.