Dear authors,

I thank you for the detailed answers given to referees of your paper. I consider these answers acceptable, except for one concern that I suggest you to adress in a minor revision of the paper.

Reply 25 (and also response 41). "Generally speaking, modern modeling does not look as highly as in the past on validation. e.g. Anderson et al. (2015) Applied Groundwater Modeling P. 19 . The terms model verification, code verifi-cation, and model validation are not in the workflow because verification and validation, as historically used, are no longer critical elements in groundwater modeling". Validation remains a necessary step in any modelling study. Research should be evidence based. If no validation is needed, than our hydrological science practice reduces to speculation. Of course, in many cases validation is difficult, if not empirical impossible. In such cases, this flaw should be addressed in the discussion and should be described as a clear hypothesis on which the conclussions are drawn. I therefore suggest to revisit this statement.

I recommend to prepare and upload the revised version of your paper, taking into consideration the suggested modifications in your referee reply reports and the my above mentioned suggestion.

Sincerely yours,

Congratulations with this nice contribution to hydrological sciences.