Based on the reviews we received for this paper, I recommend a major revision before the paper can be accepted for a regular issue of the HESS journal. The two most important reasons for this decision are:
1. The paper mentions an experimental set-up / study area, but reports no true monitoring data (it lacks detail statistical assessment of how well do the theoretical models match real data). There is no actual proof that the theoretical assumptions (significantly) match ground observations.
2. The paper needs a serious re-writing (see Anonymous Referee #2 comments) both (a) to justify a need for this research, (b) and to explain what are the consequence of the research results to the wider hydrological community (who and how could make benefit from your research?).

Unfortunately, I have no choice but to advise the authors to consider the reviewer comments and produce a major revision of the article and then resubmit to HESS or similar journal. It could also very well be that this article would be more suited for a journal that covers mathematical aspects of geometry or similar, i.e. not as applied scientific field such as geomorphometry and/or hydrology.

The paper has been significantly improved. Most importantly, the authors have (a) added a comparison / evaluation of their model using a real data set, and (b) responded to all detailed comments and implemented requested changes. I would recommend publication of this article in this special issue.