This paper has now been reviewed by two reviewers and the authors have responded to the reviewers’ comments.

I am generally happy about the comments made by both reviewers. One suggestion by reviewer 2, i.e. to make the results section more concise, was in fact not honoured the authors, as I could not detect any significant shortening of the results section.

This I find this rather problematic, because although the manuscript is generally well written, the manuscript at the same time was for me tedious to read, mainly because of the complex abbreviations and terminologies used. In that sense it is not a very appealing paper, which may affect the readership. So it is in interest of the authors to try to make this paper better accessible.

This not only holds for some of the acronyms used but also for some of the figures that are not easily read nor understood. I explain this below.

Acronyms used: Normally in this type of papers, comparing scenarios is among the more interesting aspects. This requires the scenarios to be clearly identifiable and understandable. But in this paper the scenarios are many, and cannot be easily understood because of the use of codes (what scenarios are meant with, e.g. S1-0-4-c and S2-1-p-c?). The make things even more complex, the text is ridden with LRR1, LRR2 and LRR3, but the meaning of n is only declared somewhere in brackets (line 306 in the original manuscript, whereas the concept of LLR is introduced much earlier, in lines 206-212).

Figures: Graphs of findings that need to be compared would benefit from graphs with identical scales. E.g. comparing Figs 7 and 8 is not easy, as their Y-scales (I mean the scales for e.g. Fig 7a-1, 7a-2, 8a-1 and 8a-2, same for 7b-1,7b-2, 8b-1,8b-2) differ. They should be identical, so that you can better compare them. And why not include in both graphs what the a, b, c scenarios (the columns) are, and what the 1 and 2 scenarios (the rows) mean? I understand that the rows mean without and with IWD, and the column mean a = S priority, b = H priority and c= E priority. This is not even written in the caption

To confuse matters further, Figure 9 uses columns to distinguish with and without IWD, and rows to distinguish the priorities for S, H and E.

And figure 10 I found even more confusing. I really failed to deduce anything interesting from it. That is either my own failure or the failure of the authors to effectively communicate their findings.

For the figures 10, 15, 16 and 17 I couldn’t decide whether it is critical to use identical colour units/scales, which I normally would favour. I therefore ask the authors to explain why they decided to use different scales.

To come back to my initial point: the results section could focus on only two of the three result schemes: monthly, seasonal and annual. Decide on which two of these three are the most pertinent and clear. And present the third one as supplementary material. The result session should therefore be reduced by one third from 330 lines to only 220 lines.

In addition, and this is a completely separate comment, and aligns with reviewer #1: you now have called section 4 “Results and discussion”, but there is hardly any discussion. I would recommend you to include a new “Discussion” section, in which you (critically) discuss the value of your work by referring to what other experts have done. That can be perhaps be done in half a page.

I have some further (rather detailed) comments that both reviewers did not (bother to) mention (line numbers refer to the original manuscript):
It would be useful to mention somewhere in the beginning of the paper that the concept of IWDP is identical to what many other authors call inter-basin water transfers (IBWTs).

Line 107-109: you write “It has been widely application in runoff simulations across various basins worldwide, consistently yielding outstanding results.” Give references

Line 119: PBLAS Do you mean PBIAS?; see also lines 126 and 127

Line 163: the parameter EF is introduced, with without any definition. What does EF mean? In what unit is it expressed?

Eq. 13: the factors g (gravitational acceleration) and rho (density of water) are missing

Lines 191-192: “ … and ecological water supply for the outside of the river)… ???? I do not understand this sentence

Figure 2: 1) what about precipitation on the lake; is that ignored? 2) what does “abandoned water” mean? Why are releases for other uses than hydropower and “abandoned water” apparently excluded?

Line 206: “quantization method”: explain

Line 209-210: you write ”rn is the value of the nth index, and rc(n) is the value of the nth index need to be compared. ” This is an unintelligible sentence.

Lines 210-211: Can you explain better what the value of LRR mean? If they are positive, what does it mean if values differ from e.g. 0.5 to e.g. 15?

Lines 219-224: the priority for S is expressed by simply increasing it by 20%. But that is in my view not a normal or conventional way of dealing with prioritization of water allocation. Please justify this approach.

Lines 227-230: you write “Thus, the differences between Nexus Ⅰ and Nexus Ⅱ can figure out the impacts of IWDPs on the SHE nexus. To identify the SHE nexus with different clusters of IWDPs (i.e., the feedback loops of Nexus Ⅲ as shown in Figure 1.), the differences between S2-m-p-c and S1-0-4-c scenarios are determined. Thus, the differences between Nexus Ⅰ and Nexus Ⅲ can figure out the impacts of IWDPs on the SHE nexus.”

The above text consists of three sentences of which the first and the last are identical. There must be something wrong here.

Table 2: Explain the difference between scenarios S1-0-4-1, S1-0-4-2 and S1-0-4-3; and between S2-3-4-1, S2-3-4-2 and S2-3-4-3

Table 2: You could simplify the scenario number by one level by simply removing the first digit of the scenario name (1-0 becomes 0, 2-1 becomes 1, 2-2 becomes 2 and 2-3 becomes 3). For me simpler and therefore clearer.

Line 238: acronym HR not explained

Figure 5: The IWDPs are not very clear in this figure.

Fig 5 and Table 3: The link between Fig 5 and Table 3 is not easy because of the naming of the reservoirs. Try to make things easily understandable for the reader, if you want your paper to have impact!

Table 3: 1) why haven’t you included the year in which each reservoir was put into operation?
2) What is the unit for hydropower generation efficiency?
3) What is the unit for regulation ability: residence time? If so, the unit is time

Results section: you give many values for LRRn, and all with three decimals, suggesting a very high accuracy, although you have only in a very summary way (lines 210-211) explained what these values really mean. Improve this.

Lines 614-615: you conclude: “All feedback loops are strengthened in low flow periods accompanied by their greater or smaller values of LRRn than other periods. If there was only water donation, all values of LRRn for the reservoirs are lower than those without IWDPs, while all values of LRRn for reservoirs are greater than those without IWDPs.”

A very straightforward conclusion, but as I do not know what the value of LRR means, it doesn’t resonate with me and I will not remember what it really means. So it would be much better to simply state what these changes in value imply in the real world.

Thanks to the improvements made, the manuscript now reads much better, although it is still hard work to read the paper, and there remain many minor grammar weaknesses, which I do not have time to address. (But if the authors would share the word manuscript, I could make an attempt to edit it.)

Also I suggest that the following needs to be clarified:

1. At several instances the paper refers to “reservoirs group” (e.g. lines 15, 47, 84, 205, 207, 215, 217 etc.), which nowhere is defined. This definition is needed because “reservoirs group” is not an established concept.

2. At several instances the paper uses the term “collaborative states” (lines 14, 85, 101, 597, 615). Is this the same as “synergies”? I am not sure whether “collaborative state” is a felicitous term, as it may suggest that there is a “volition” of working together, but that’s not what this is about. In practice there is either a synergy or a trade-off or an absence of interaction.
It is in my view noteworthy that in a nexus paper the word “synergy” is nowhere mentioned. Similarly, equally surprising is that the concept of trade-off is nowhere mentioned in the text.

3. Why not call NEXUS I -> NEXUS SH; NEXUS II -> NEXUS SE, and NEXIS III -> Nexus HE (see e.g. Fig 1, line 223, 258, 259, 260, 261, 262, 263, 265). Reads much more easily, as it is more intuitive.

4. Table 3:
- Usable storage: why not use the more convention unit 10^6 m3 rather than 10^8 m3?
- “Annual generation” -> “Energy generation”
- Correct unit: billion kWh/yr (not billion kWh)

5. Typos / minor grammar issues in the manuscript:
a. Line 133: lager -> larger
b. Line 245: denoated -> denoted
c. Line 263: “can figure out” -> “show”
d. Line 279: “15 cascade reservoirs” -> “a cascade of 15 reservoirs”
e. Line 588: “in consisted with that in Hutuo River Basin” -> “consistent with those of the Hutuo River Basin” OR “inconsistent with those of the Hutuo River Basin” [I do not know which one of the two is meant. Carefully check!]
f. Lines 617-618: “will be figured out” -> “can be elaborated”

I appreciate the improvements made. There are however still a few remaining issues that require clarification.

One is the use of the term "collaboration" that I understand to mean, in the specific context of this paper, synergy.

Another is the statements referring to the positive or negative impacts of feedbacks. Such formulations remain unclear, as what is a negative impact for one, may be a positive impact for another. So this requires a more neutral (I mean non-normative) description.

I also feel that one finding of your study, which I find the most important finding, is not featuring in the conclusion nor in the abstract. It is written in the discussion section as follows: "The persistent feedback polarity with IWDPs suggests that simply increasing water supply (e.g., via compensation donations like Three Gorges-to-Hanjiang) cannot resolve inherent SHE conflicts." This conclusion is important for me, because inter-basin transfer schemes are often portrayed to solve such water conflicts.

Furthermore there are still many minor editorial issues, which I have indicated (in track changes) in the word file that I received from the authors, and which I will return to them via email (as this copernicus environment doesn't allow me to attach word files, while a converted pdf would obscure certain editorial details). Therein I also make several suggestions for editorial improvements.

I trust the authors will be able to address the above in a hopefully final round of revisions.

I am happy with the final touches that the authors made to the manuscript. In my assessment, the paper is now ready for publication in HESS.