Hydrokinetic devices have lately reemerged as a promising solution for harnessing energy from renewable sources such as rivers, tidal currents, or artificial channels. This paper describes a customized test flume that is capable of conducting tribological related experiments on sliding components (bearing, shaft, and generator seals) commonly used in hydrokinetic devices. Often while deployed, wear on bearing, shaft, and seal assemblies introduces undesirable clearances between contacting surfaces, which potentially can affect the performance of hydrokinetic devices. In order to investigate wear occurring specifically in bearing-shaft assemblies under conditions similar to those expected in the field, a flume was developed. The flume has the ability to recreate the hydrodynamic, salinity, sedimentary, and mechanical loading similar to field deployment. The wear rate data collected after 60 h of clear-water tests on four different types of bearings is presented. In addition, an approach is described whereby the coefficient of friction occurring within the bearing assemblies is estimated as a function of applied load.