Computational Model of Water Distribution Network Life Cycle Deterioration
Round 1
Reviewer 1 Report
Dear Authors,
In my opinion this paper is very interesting, the english is good but I would like to comment/suggest the following:
Some citations are not correct. In my opinion, lines 58-59 should be: .. “leakages tend to increase as the WDN ages, as observed by Engelhardt et al [22] and supported by the findings of Lambert [23], who …”. There are much more in the introduction that are not cited correctly.
Equation 1 is so easy and logical – remove
Equation 3 – variables and parameters units should be indicated.
Equation 3 – significant digits (s.d.) are correctly indicated for a, b, c and d numbers? How is it possible “a” has only 4 s.d. and “d” has 11 s.d.? Please remove digits that are significant.
Equation 5 to 10 – I would like to ask you to review all the calculus or improve the references of the variables and parameters and their units. The units should be consistent and in same equation you mix units like meter, millimeter, and liter(=m^3) or hour and second (see eq 8). How do they cancel? I am not saying that everything is wrong but I not used to see that in engineering equations.
Equation 8 is one that looks to me very strange and units are not consistent. Can you please include the units you did not mentioned? and check if they are ok?
Line 249 and table 5 – again numbers without units
Results section – re-write again including what other authors found to compare with your results.
Author Response
Dear reviewer, I forward responses to the considerations made and thank you for the review.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Authors presents a computational model for simulating the deterioration of Water Distribution Networks (WDN) throughout their lifecycle. It investigates how various factors impact the operation, including population-driven water demand growth, pipe deterioration due to increasing internal roughness, changes in network leakage influenced by population size and network parameters, and the aging of pumps. The study underscores the critical importance of maintenance services for optimizing WDN performance, highlighting that leaks exert the most significant impact on operating costs.
1. Can authors explain the rationale behind using a third-degree polynomial adjustment for population forecasts (Equation 3) in SC1?
2. Provide a more detailed explanation of the pump deterioration mechanisms mentioned (cavitation, corrosion, fouling, misalignment, excessive vibration).
3.Elaborate on the practical implications of different parameter change rates in Table 5. How do varying rates of ?? and ? impact the performance and maintenance requirements of pumps over time?
4.While it's mentioned that scenarios SC1D3, SC2R3, and SC4P4 have similar total annual costs, it would be beneficial to provide the actual numerical values to enhance clarity and enable readers to understand the cost differences more precisely.
Best,
Author Response
Dear reviewer, I forward responses to the considerations made and thank you for the review.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Dear authors
I agree with the changes introduced. I consider that the article was improved and is now ready to be published, although the units cause some confusion (for example, millimeters and meters in the same equation). But I accept that these types of models may be developed in this way and I also verified that they really have dimensional consistency.
Reviewer 2 Report
Authors have addressed my comments, and I have no further questions. I recommend accepting this paper。
