Flood Season Staging and Adjustment of Limited Water Level for a Multi-Purpose Reservoir

Round 1

Reviewer 1 Report

This work has used statistical analysis on rainfall and runoff data to evaluate the different scenarios for optimizing the functioning of a multi-purpose reservoir located at Hongshui River, China.

Here are some of the comments for the authors to improve this manuscript

1. Introduction lacks the global perspective of the research problem. For the international audience, this work needs to be structured with its relevance to other parts of the World, specifically the Himalayas. It looks like a local study. Start from global, then regional, then local then describe the methodology and the novelty of the work. This is how the introduction for an international audience is supposed to be written.
2.  Methods lack the fine details. How the data has been processed, which program/ software has been used. Simply defining the variables of the equations without referring to what they mean in the current study is a huge knowledge gap in the present work. The parameters of the equations need to be referred to what they from the data used.
3. The results section needs to be started with a section what are the prospective aims and how they have been achieved in the present study. It looks like we are just reading a statistical report without any inferences to the problem statement.
4.  The discussion is too short. There is a substantial amount of information in the results section that can be shifted to the discussion section. Moreover, a separate last paragraph in the discussion is necessary to conclude the overall work.
5. Research gaps and limitations of the present work need to be added as a separate section 
6. A lot more can be discussed regarding the influence of the changing river water discharge under climate variability scenarios in the study area
7. Revise the study area map and show the reference of it to China.

Author Response

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Reviewer 2 Report

This study investigates the flood season segmentation in a reservoir to optimize the flood water level. The topic is interesting and well suited for the journal Water. However, I have several comments on the manuscript that I would like the authors to address before the manuscript can be accepted for publication.

• I feel the authors used the terms “hazard” and “disaster” synonymously in the manuscript, which is incorrect. For instance, in line 33, it should be “flood hazard” not “flood disaster”.
• Line 33-42: multiple references are expected.
• The introduction section should be reorganized. Since this study is focused on a form of flood intervention, I feel, the authors should review various alternative flood risk reduction measures and report them in the manuscript. The literature should be based on different regions of the world. The following studies could help improve the background of the study:

https://doi.org/10.1016/j.scitotenv.2020.138747

https://doi.org/10.1016/j.crm.2019.04.001

• Line 74: “In summary, though interesting results have been obtained …”. Such an expression should be avoided. The term “interesting” is not measurable.
• Lines 75-80: Each of these statements should have multiple citations. Besides, the authors need to explain why such challenges exist.
• Section 2.1: The authors need to justify the selection of the study area.
• Section 2.2: The authors only explain the “Seasonality index method” and “Fractal method”. But it is not clear how these methods helped to achieve the objectives of this study. Besides, they need to clearly write the type of data used, as well as their sources.
• How did the authors validate the simulated flood processes?
• How are the uncertainties in the results treated?
• The discussion section needs further elaboration to justify the validity of the findings.

Author Response

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Reviewer 3 Report

Review of the manuscript entitled "Flood Season Staging and Adjustment of Limited Water Level for a Multi-purpose Reservoir"

General comments: This study analyzes the flood season segmentation and optimizing the staged flood limit water levels (FLWLs) for a multi-purpose reservoir-the Longtan Reservoir, China. To evaluate the feasibility and rationality of the flood season staging the rainfall seasonality index and the runoff seasonality index were used. The fractal method is then applied to divide the flood season and the design flood is carried out to optimize the staged FLWLs. Results show the SI is an effective indicator for judging the feasibility of staging and verifying the rationality of staging. The FLWLs in the main flood and the post-flood season can be increased by 2.05 m and 3.45 m, respectively.

Opinion: I think this is a good manuscript focusing on a highly relevant topic although the study is not new.

Introduction: The introduction provides useful information for the readers. But the literature is not adequate and I recommend that you consider incorporating key references as well. Also, the flow in the introduction is not smooth and I recommend the authors revise this section.

Materials and Method: The methodology is clear and transparent, and the research procedures and techniques used are standard and reproducible. I recommend authors state the study limitations as well.

Result and Discussions: I have few issues with the presentation of the results. The figures are well presented to help in clear visualization (see detailed comments below). The discussion section supports many aspects of the findings and is done within previous studies.

Minor comments:

Line 180-181: Figure. 2 The variations of the SI_p and the SI_R. I suggest to avoid confusion the use same color of the trend line as the points (i.e., SI_p point as red squares and SI_R as circles. Alternatively maintain black color for all.

Line 183: Figure. 3 Percentage of each level of the SI_p and the SI_R. for the entire flood season. Remove gap for <0.19. Why have large gaps between the categories? Reduce to them.

Conclusion: The section is well written and supports the findings. Study shortcomings statement was provided and made recommendation for further studies

Other minor comments

Line 344: Delete 7.Patents

Line 362: replace “application” with “applicable”

Tables placed in the supplementary list should be labelled as Table S1 etc. Revise

The overall contribution of your research could be greatly strengthened by considering a few comments raised. However, English language editing is required. I strongly recommend that you engage the language editing services or a native English speaker to improve the manuscript.

Recommendation: Accept with minor revision

Comments for author File: Comments.pdf

Author Response

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Reviewer 4 Report

The title of this paper is “Flood Season Staging and Adjustment of Limited Water Level for a Multi-purpose Reservoir”. The title of this study is interesting. However, there are many contents that need to be corrected. Therefore, I recommend a major revision in this paper.

Comments for author File: Comments.pdf

Author Response

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Round 2

Reviewer 1 Report

Thanks for incorporating the suggestions.

Reviewer 2 Report

The authors have adequately addressed my comments. I recommend "accept" of the revised manuscript. 

Reviewer 4 Report

The title of this paper is “Flood Season Staging and Adjustment of Limited Water Level for a Multi-purpose Reservoir”. This paper has been well revised taking into account all comments. Therefore, I recommend an accept in this paper.