Nested Recharge Systems in Mountain Block Hydrology: High-Elevation Snowpack Generates Low-Elevation Overwinter Baseflow in a Rocky Mountain River
Round 1
Reviewer 1 Report
The manuscript water-1320328 concerns on the use of the isotope hydrology (δ34SSO4 and δ18OH2O) to separate the different streamflow components in an Alpine-type case study drainage basin (Elbow R. basin, Alberta, Canada). In the Elbow R. basin, characterized by carbonate and terrigenous units, the streamflow originates from snow melt and warmer or colder rainwater depending on the altitude. Baseflow contributions from each of the carbonate and terrigenous units were differentiated by using sulphate and silica content, while water isotopes composition was used to estimate relative temperature and/or altitude of the original precipitation. Baseflow in the upper reaches of the basin was generated from lower elevation and/or warmer precipitation primarily stored in the terrigenous unit. Conversely, baseflow generated at the lower elevation reaches originated from higher elevation and/or colder rainwater stored in the carbonate aquifer. The results show that at higher elevation snowmelt infiltrates through the fracture network of carbonate aquifer, moving to the lower elevation valley through intermediate flow systems, while winter baseflow in local flow systems of the terrigenous valleys reflects more influence from warmer precipitation.
I think the manuscript is very interesting, and it can be useful for all the scientific community involved in the Isotope Hydrology of the Alpine-type basin. So, after having carefully read the manuscript, I think it can be accepted with minor revisions.
Main comments
Fig. 2: are you sure that the groundwater of sampling point 13 comes also from a deep and long flowpath. Can that groundwater flows transversally to the section? Explain please
Results and Discussions paragraph: please I warmly suggest adding also a schematic cartoon illustrating the groundwater flowpath and the interaction between the stream water and groundwater during time. The cartoon could be more or less similar to the graphical abstract.
Conclusion paragraph: reword the conclusions with the bullet point approach evidencing the main results of your study.
Minor comments are reported in the attached pdf file.
Comments for author File: 
Comments.pdf
Author Response
Please see the attachmentAuthor Response File: 
Author Response.docx
Reviewer 2 Report
The work is interesting, relevant and complements the research done by other researchers.
Notes -
1. There is no clearly stated aim of the work.
2. In the introductory part of lines 109-112 this is the methodology, further to lines 117 already the results.
I recommend to finish the part of the commander for the stated aim of the work.
3. No sampling schedule is provided. Are samples taken only once? This is not enough, because seasonal variation is not estimated.
4. Have quality standards (ISO or other) been applied to the analysis of the samples?
5. What mathematical data processing methods have been applied? It should be a separate part of the methodology.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
I think it is possible to print the article. The article has been corrected after the comments
