Experimental determination of free surface levels at open-channel junctions

The Author is acknowledged for extending knowledge of open channel confluences by providing additional experiments. More specifically, the Author's research offers a dataset with inclined channels, including not only fully subcritical flows (Type I flow), but also flows with supercritical flow in one upstream branch (Type II flow) or upstream and downstream branches (Type III flow) of the confluence. Moreover, the experimental data are used to assess the accuracy of Taylor's model for predicting the increased water levels over a confluence. In this Discussion, we would like to address some issues that are not fully covered in the paper. First, the Author's experimental data will be compared with existing datasets available in the literature. Secondly, it will be verified whether the hypotheses on which Taylor's model is based are met in the Author's experiments, in order to allow a fair comparison between the model and experiments. The Discussion is focused on the Type I and II flows