More Effective Front-End Decision-Making for Pipe Renewal Projects

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors This article reviews the definition and project model of pipeline renewal projects, and compares them with the typical characteristics of other infrastructure projects. Some comments and suggestions are as follows: 1.The abstract does not summarize the key findings of the review or the specific features of the proposed project model. 2.Please do not include references in the abstract. 3.The authors should clearly define "Pipe Renewal" on to specify whether it includes replacement, rehabilitation, trenchless technologies, and new installations. 4.The description of the "mixed methods" approach in Section 3 is vague. The authors state they use observations and professional experience, but the core of the study is a systematic literature review. The flowchart in Figure 3 is helpful, but the authors need a more rigorous explanation of the literature search strategy, including the specific databases searched, exact search strings used, inclusion/exclusion criteria, and the number of papers identified, screened, and included. 5.The authors use many acronyms without always defining them upon first use. For example, when DSS first appears in line 72, there is no corresponding full term or definition. 6.The review lists various existing project models (Governmental, Next Step, RIBA) but provides only a superficial comparison. A more critical discussion is needed: Why are these models unsuitable for pipe renewal projects? What specific characteristics of pipe projects？ 7.The authors state that a model was developed for pipe renewal but does not succinctly summarize how it improves decision-making, which was the central research question. 8.The paper structure is missing, the authors can add a paragraph in Introduction to illustrate the main work of each section. 9.Adding a discussion part is suggested to explain your method limitations and future directions for related studies.

Author Response

Thank you for your constructive comments. They have been taken into consideration and answered point-by-point in the attached document. The manuscript has undergone a major revision. Changes in the manuscript is marked with blue font text.

Best regards,

Bjørn S.Skaar

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

The paper is relevant as it tackles the important challenge of improving decision-making in pipe renewal projects through a tailored project model that links planning, execution, and asset management. The study addresses a topic of practical importance for utilities and infrastructure managers; however. The following comments should be addressed:

Comment 1: Abstract imrpovement

The abstract could be improved by making it clearer and more concise. References should not be included in the abstract, as it should focus on summarizing the problem, aim, method, findings, and contribution. A common and effective structure is: context of the problem, research objective, method used, main results, and finally a statement of relevance. Ending with for whom the study is most relevant (e.g., municipalities, utilities, policymakers) would strengthen its practical impact and readability.

Comment 2: Novely of the work

The unique contribution of the study could be made more explicit. I recommend that the authors clearly state, both in the abstract and conclusion, that the novelty lies and what was never done before.

Comment 3: Redundancies

The manuscript contains some redundancies in both the text and figures that could be streamlined to improve readability. Certain concepts, such as the role of front-end planning and the links between asset management and project models, are repeated in several sections, which makes the paper denser than necessary. In addition, one figure appears to be reused with only minor additional details, which may confuse readers and reduce the overall impact. Consolidating overlapping explanations and merging or differentiating figures would strengthen the clarity and flow of the paper.

Comment 4: The concept of a project

The discussion on conceptual development is highly relevant but would benefit from clearer framing. Currently, the term is applied across different contexts (front-end planning, project step models, and asset management) without a consistent definition of a “project,” which makes comparisons difficult. I recommend that the authors provide a concise definition of what constitutes a project in the context of pipe renewal, covering scope, expected costs, and other key parameters, what is the minimal requirement to call something a pipe renewal project, and explain how conceptual development fits within this definition. This would reduce ambiguity and strengthen the positioning of their proposed model.

Comment 5: Methodological issues

The methodology is described in detail, but it could be made clearer and easier to follow. While the authors explain the steps of the review, it is not fully clear why a mapping review was chosen instead of a full systematic review. It would also help to explain more about how papers were selected or excluded, and how possible biases were handled. Adding these points would make the study’s approach stronger and easier for others to repeat.

Comment 6: Project management context

A general weakness of the paper is the limited attention to established project management techniques. While the focus on decision-making models and asset management is valuable, the study does not sufficiently integrate methods such as risk management, scheduling, cost control, or stakeholder engagement that are central to project management practice for the addressed infrastructure. Including or at least discussing how these techniques could complement the proposed model would strengthen its practical applicability and make it more useful for implementation.

Comment 7: Discussion and conclusions

The discussion offers useful comparisons with existing models but is somewhat repetitive and would benefit from a sharper focus on what the proposed project model contributes beyond current frameworks, particularly in terms of practical value for municipalities and utilities. The conclusions, while covering the main points, could be shorter and more impactful by clearly stating the unique contribution, offering concrete recommendations for practice, and suggesting directions for future research.

Good luck with the revision, and best regards,
Reviewer

 

 

Comments on the Quality of English Language

The manuscript is clear overall, but it contains long and dense sentences, some redundancies, and awkward phrasing that reduce readability. Shorter, more concise sentences and smoother transitions would make the arguments more accessible, especially for an international audience.

Some examples that should be simplified:  

Developing new and effective methods for the planning and execution of pipe network renewal is necessary to help close the infrastructure gap.

The results of the research reflect the distinctive nature of the pipe renewal projects, narrowing the observations from overarching organizational processes to operational distinctive project phases.

Furthermore, the utility of adding information is the highest early in the projects where the space of opportunity for solving the problem is the largest, while the cost of changes to the concept is the lowest.

Author Response

Thank you for a thourough review and constructive comments. Based on your comments we have made a major revision to the manuscript. Answers to your comments are done point-by-point in the attached document.

Best regards,

Bjørn S. Skaar 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have addressed the previous feedback. I therefore recommend accepting the manuscript for publication.

Author Response

Dear Reviewer,

Thank you for recommending the article for publication. There has been a minor revision to the manuscript. However, the changes have not impacted on your previous comments. 

 

Best Regards,

Bjørn S. Skaar

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

Thank you for the careful and substantial revision of the manuscript. The paper is clearly improved, though a few points would still benefit from further refinement.

Comment 1:
The revised abstract is much clearer but could still be tightened. Consider adding a sdtrong short sentence that highlights the main outcome / contribution.

Comment 2:
The originality of the proposed model remains quite implicit. Please specify more clearly what differentiates your framework from existing models such as RIBA, QA1/QA2, or ISO-based project systems.

Comment 3:
The relationship between conceptual development, front-end planning, and asset management could be more sharply defined. A brief paragraph summarizing how these layers interact would make the paper easier to follow.

Comment 4:
A few sections remain slightly dense. Light editorial polishing for flow and conciseness would improve the overall readability of the manuscript.

The paper was substentially improved.

Best Regards,
Reviewer

Comments on the Quality of English Language

The overall quality of English is satisfactory and clear, with consistent terminology and professional tone. However, several sentences are overly long and could be simplified to improve readability. 

Author Response

Dear Reviewer,

 

Thank you for the constructive comments. The authors have replied in the attached PDF-file. 

 

Best Regards,

Bjørn S. Skaar

Author Response File: Author Response.pdf