I believe that, if the authors incorporate the changes noted in their response, that the major comments of the reviewers will be resolved. However, because the revisions are substantial (adding of new tables and text), the manuscript will be reconsidered after these major revisions.

Both reviewers note that the research is sound but that the presentation of the results needs to be improved for clarity, particularly because of the number of methods being compared. I believe the author's responses to revisions related to further justification of the impact of this research will also clarify the contribution of this work.

I have read the revised manuscript carefully as well as the reviewer comments. I agree with the second-round review that the manuscript has been improved and many of the original reviewer comments have been addressed; however, I still feel major revision is required to accept the manuscript for HESS.

The work itself is relevant as the paper provides the first global comparison of ecological flow methods. For this reason, I believe the topic and the work itself merits publishing. However, the manuscript still contains too many grammatical and editorial errors still apparent after revision and the readability of the manuscript, especially the results, discussion and conclusions, needs further improvement before the manuscript can be accepted.

I list several places where these changes need to be made but the manuscript requires a full review for clarity, consistency and grammar. It is very difficult to still interpret your results until these aspects of the manuscript are resolved.

Also, please take special note of the manuscript preparation guidelines for HESS to ensure your manuscript follows the Textual and Visual Conventions: http://www.hydrology-and-earth-system-sciences.net/submission/manuscript_preparation.html.

1. Use of quotes around the names of the flow methods is not necessary. For example, in the abstract (line 4) and Section 2.1 (p. 5, line 7). Please remove.

2. Clarify the difference between ER and EFR in the text. They appear to be used interchangeably and this makes the manuscript confusing to read. Either choose one term or make explicit note as to the differences in meaning between the two terms.

3. When referring to the environmental flow methods later in the text, be consistent in the usage of the categories described in Section 2. This adds confusion to the reader in the later sections about how the various hydrological methods and locally calculated methods are different. Why not organize section 2 into sections titled “Hydrological methods” and “Locally-calculated methods”? You say you are going to use hydrological methods but then in Section 3.1, you state that, in the case studies, you use habitat simulation models or a holistic model, which are in different sub-sections of Section 2 than hydrologic models. This is very confusing for the reader.

4. In some cases you choose to create abbreviations for site names or methods and in other cases you do not. Be consistent. For example, Section 2.4, you define the acronym DRIFT but do not use one for the Building Block Model or Desktop Reserve Model. Similarly, in Section 3.4, the Bill Williams River is abbreviated BWR but the Sharh Chai River is not. Be consistent.

5. Equations 1 and 2 are not in the proper format required by HESS.

6. You need to make a stronger case for why you are comparing local EFRs to global. One way to do this is to explicitly state the assumption in the earlier sections that you are assuming the local EFRs are the best estimate of the ecological needs of the river and using that best estimate to compare against the global EFRs. This connection is very difficult to see in the current version of the manuscript.

7. You seem to contradict yourself in Section 3.6.2. You state that it is “essential to define EFRs at shorter timescales than annual timescales…” (lines 29-31) but then later state that you use a method based on annual quantiles (line 5). This is quite confusing. Also, the use of “should” needs to be removed. State what you did for your analysis and why you did it; do not make a blanket statement about what should or should not be done outside of this analysis.

8. In Section 3.6.1, when assigning all rivers as “fair” does this mean that you used the corresponding Q values that Smakhtin et al 2004 used?

9. Please proofread carefully. There were grammatical errors throughout the manuscript.

I thank the authors for their persistence in improving the manuscript and taking the review comments seriously. I believe this paper will represent an important contribution to the ecohydrology community. The paper should be published as is, subject to one very minor change: please add the text in section 5.7 to the end of section 5.6 and delete the heading for section 5.7. I do not think there is enough text in 5.7 to support having its own section.

I wish the authors all mthe best on their future research endeavors and thank them again for their time in revising the manuscript.