A theoretical analysis was made of the reflected and transmitted waves which were produced when a water-hammer pressure wave encountered a tee in the pipeline. The analysis included the fact that a hydraulic loss existed across the tee. Relationships were developed for determining the magnitude of the reflected and the transmitted waves. However, these relationships were only suitable for the case of instantaneous valve closure, due to the relative magnitudes of the terms involved. An experimental analysis was made in order to verify the theoretical relationships. However, due to malfunctions of the equipment and the ill designed pipeline configuration, very little of the information that was desired could be obtained. Hence, the theoretical analysis could not be verified. / Master of Science