Overbank flooding is a ubiquitous condition in natural rivers that modifies floodplain sediment dispersal and impacts channel mobility. While variable discharge is a critical component driving these processes, fluvial landscape evolution is typically modeled by simplifying the hydrograph to an equivalent steady discharge; namely, the channel-forming discharge. In this framework, changes in the hydrograph only affect landscape evolution if they modify the channel-forming discharge, but different formulations for the channel-forming discharge can generate a range of predictions from the same input hydrograph. Here, we investigate how hydrographs with different flood intensities affect channel mobility, sediment accumulation patterns, and alluvial morphology using a suite of physical experiments where a fan delta grew by dispersing a cohesive sediment mixture into a basin. Flood intensity (\(Q_v \)) was defined as the ratio of the maximum discharge to the minimum discharge, i.e. \(Q_v = Q_{max} / Q_{min}\). The experiments spanned three levels: no flooding, low-intensity flooding, and high-intensity flooding, while the time-averaged discharge was equivalent between all flooding regimes. This dataset is an HDF5 dataset, which is a general format. The data largely consist of a set of 3D arrays that contain 2D topography and imagery data, where the third dimension is time. Each data object is paired with a 1D vector that links datasets across the time dimension, since data were collected at different intervals. The appropriate linking datasets are also included as CSVs.