This paper examines the potential of high resolution UAV-data for surveying sediment dynamics. For this purpose, a test area (Langgriesgraben, NP Gesäuse, Austria) was selected in a channel with episodic discharge and high morphodynamics. High resolution UAV images (mean GSD 2-3 cm) from three survey dates were used to derive digital point clouds, digital surface models and orthophotos using the SfM-MVS method. The processing was performed with Agisoft Photoscan Professional 1.2.4. Ground control points, measured with a dGPS, were used for georeferencing. The height accuracy from the raster terrain models and the planar accuracy of the orthophotos were estimated from dGPS measured check points using different statistical parameters. The achieved accuracy (e.g. height accuracy DTM: 4-7cm RMSE) is in the expectable accuracy range found in literature. Shadow areas in the aerial images are leading to areas with higher uncertainty in the derived DTM. The digital point cloud and the DTM were compared with TLS data on three selected test sites. The deviation between UAV and TLS is 6-12cm (percentile 95 of the deviation) depending on the method used for the comparison and test site. It was possible to estimate the surface change in the channel with the derived UAV-terrain models. The DoD method with a minLOD was used to accomplish that task. Based on the calculated minLOD (14cm) a significant change could only be estimated at 12% of the total area. In the observed period (53d) the deposition (295m) predominates the erosion (163m) of sediment. The results show that the used method SfM-MVS in combination with an UAV is able to detect bigger rates of change. Smaller changes, however, are not detectable due to the reached accuracy.