This paper aims to evaluate the process of erosion and sedimentation in alluvial channels in three winding sections of the channel of the Marinilla stream, to identify its mobility conditioned by human intervention and base level fluctuations in the Negro River. This mobility is evaluated using the CCHE2D numerical model to simulate processes of aggradation and degradation on the channel and its morphological changes. According to the results, bridge structures implemented on the bed of the Marinilla stream and fluctuations in the level of the Negro River can modify and limit the mobility of the channel in time.