Evaluation of Pipe Materials in Water System Networks Using the Theory of Advanced Multi-Criteria Analysis
Round 1
Reviewer 1 Report (Previous Reviewer 1)
This paper used a multi-criteria analysis method to identify the most optimal pipe material in a water distribution system. The reviewer thinks this is important and timely research. The literature review has covered rich information. The proposed multi-criteria analysis is useful for the utility's decision-making process. The limitations and future works are well discussed in the Conclusion. The draft is well-organized and written. The reviewer thinks it is ready to be published after minor revisions.
(1) The authors should briefly discuss how table 1 is determined. Is it identified by questionnaires or expert opinions?
(2) The following references should be discussed as they are related to the recent progress in water pipe and water system failures.
https://doi.org/10.1016/j.ress.2021.108185; https://doi.org/10.1016/j.ress.2023.109088
Author Response
Dear reviewer,
Thank you for evaluating Pipe Materials in Water System Networks Using the Theory of Advanced Multi-Criteria Analysis for sustainability. I appreciate your thoughtful comments and time spent reviewing my work.
I incorporated your suggestions into my manuscript. I took your suggestions into account and worked to improve my manuscript. I hope you like these changes.
I appreciate your time and effort reviewing my manuscript. I am waiting for your comments and suggestions as they improve the quality of the manuscript.
Could you please see the attached file.
Author Response File: 
Author Response.docx
Reviewer 2 Report (Previous Reviewer 2)
This article investigated the evaluation of pipe materials in water system networks using advanced multi-criteria analysis theory. Although the topic chosen within the scope of the study is productive, the author should reevaluate the following points;
1. Please write the full name of the abbreviation in your first mentioned abbreviations. (For example line 60 CI, DI, Ac etc.)
2. The “%” expression used in cost comparisons in the title (1.2.3.1) cannot be understood. It would be misleading to use a percentage expression when comparing costs with each other. Also pipe diameters are an important factor in cost comparisons. Low-cost HDPE pipes in lower diameters can be more costly than DI pipes in large diameter and pressure classes. Therefore, it is not possible to make an accurate analysis with the reference diameter of 305 mm.
3. When the failure rates given in the references in the title (1.2.3.5) are examined, it is seen that the “%” approach has been used. However, in calculating the frequency of failure, the number of failures per km should be used instead of the total number of failures. Since the usage percentage of the pipe lines in the current network is not known, the calculation of the failure percentages is not applicable. It is also unclear that how the scores were calculated.
4. As mentioned in the results section, pipe diameters are chosen mainly based on hydraulic design principles, not "environmental impact and cost". I do not find it appropriate to make this evaluation over a fixed diameter, since the mentioned scoring and advantages/disadvantages vary for different pipe diameters.
5. The author should also mention the reasons for pipe rehabilitation and the factors that complicate the decision-making process in the introduction part of the article. In the introduction, it should be clearly stated why the study is needed.
6. The most important factor affecting the results in such comparisons is the scores given by the experts to the evaluation matrices. In the FRISCO method used within the scope of the study, it gains its success according to the accuracy of the scoring. In this context, it should be determined whether there is any scoring quality control for the relevant method, and if there is, whether this process is carried out (consistency calculation). Again, the number of people who made the scoring and the level of expertise of these people were not specified in the study. Also the regional conditions where the experts work will also affect the scoring as stated in the study. If the experts were selected in the same environment, the universality of the study will also be questioned.
7. Grammar used in the study should be reviewed.
Author Response
Dear Reviewer,
Thank you for evaluating Pipe Materials in Water System Networks Using the Theory of Advanced Multi-Criteria Analysis for sustainability. I appreciate your thoughtful comments and time spent reviewing my work.
I incorporated your suggestions into my manuscript. I took your suggestions into account and worked to improve my manuscript. I hope you like these changes.
I appreciate your time and effort reviewing my manuscript. I am waiting for your comments and suggestions as they improve the quality of the manuscript.
Could you please see the attached file.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report (Previous Reviewer 2)
Accept
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
This study used a multi-criteria analysis to find the optimal material of water pipes for water systems. The paper used FRISCO for calculating the criteria weights and ranking the considered types of pipes. Five different types are considered using 22 criteria. The considered criteria covered economic, environmental, and pipe properties. The results showed that FRISCO method could be used for decision-making in water systems. However, the relative importance of considered criteria and pipe scores are subjectively assigned. Therefore, the conclusions may not be suitable for a real-world problem. Some detailed comments are provided below.
(1) The introduction provides a review of the current literature. However, the paragraphs of this section need to be thoroughly reorganized. The introduction part should clearly state at least three things: (1) what is this study’s research topic and why this topic is important, (2) what are the gaps in existing studies, and (3) what are the main contributions of this study.
(2) Line 146, as the author mentioned, the real water network is often a mixture of several materials, but the proposed method can only identify one appropriate material. The author should provide a discussion about why this assumption is reasonable and how this assumption will impact real-world water network design.
(3) Table 1, how did the author get this table? How reliable are the values of this table?
(4) Again, in table 3, the values assigned to the table seem subjective.
(5) The main contribution of this study should be highlighted better. If the main contribution of this study is using FRISCO method, the author should highlight why the FRISCO method is more suited for solving decision-making problems in water system management than the other methods. If the main contribution of this study is the considered 22 criteria, the author should highlight it in the introduction part and discuss why these 22 criteria are important in decision-making.
Overall, this paper needs major revision before considering for publication. Please highlight your research impact and main contributions in both the Introduction section and Conclusion section. The draft could be valuable for specific areas if the criteria and relative importance were reasonably identified.
Also, the draft has a large room for improvement. Some words are incorrectly capitalized. And there are many sentence fragment errors.
Reviewer 2 Report
This article investigated the comparison of pipes used in potable water and sewerage networks with each other by using multi-criteria decision making methods. Although the topic chosen within the scope of the study is productive, the author should reevaluate the following points;
1. Within the scope of the study, pipes used in potable water and sewerage networks were examined together. However, potable water and sewage networks cannot be evaluated together as they have different hydraulic principles. When comparing the different criteria selected in the study with each other, it will be expected that the same criteria will get different scores according to potable water or sewerage networks.
2. The author should also mention the reasons for pipeline improvement and the factors that make the decision-making process difficult in the introduction part of the article. In the introduction, it should be clearly stated why the study is needed (The concept of non-profitable water). The introduction is too long.
3. In Title 2.1, pipe types chosen based on what? For example, why is the most used corrugated pipe in sewerage networks not on the list? It should be explained in detail.
4. In Title 2.2, chosen criterias based on what? For example, how did the author take into account the cost differences that will occur in different pipe diameters while evaluating the cost item? (Small diameter steel pipe is more costly than polyethylene pipe, while the opposite may be the case for large diameters)
5. At line 188, 232 and 239, header numbers are incorrect.
6. Previous studies on the FRISCO method used in the article should be cited. In addition, although multi-criteria decision-making methods are a very broad spectrum, why the relevant method was chosen should be clearly stated by the author. If necessary, the results can be compared by applying different methods.
7. In line 136, a thousandth separator should be used.
8. How was the comparison matrix given in Table 1 filled? Who determined the superiority of the determined criteria with each other? If it was filled in by taking expert opinion, it should be stated how many people made the relevant analysis. If literature studies are referenced, the referenced publication should be specified for each variable. The table filled in this state only states the author's own opinion and does not represent an academic value on its own.
9. Figures 1 and 2 present the same data. One should be removed.
10. Grammar used in the study should be reviewed. There are very long sentences. For example (Line 7-17, 60-68). There are very long paragraphs. (Line 23-83)
Reviewer 3 Report
This manuscript presents a comparative study on different pipe materials. There are some questions needing further explanation or revision
1. The language needs extensive revision, such as punctuation, grammar, capitalization.
2. The conclusion section needs to be enhanced. Please provide the recommendations for future work and discussion of limitations.
3. Please elaborate on the source of the data used in the study.
