Regional Water Footprint for a Medium-Size City in the Metropolitan Area of Barcelona: Gavà

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear authors. It was a pleasure to read your manuscript. The article is written in good language. The data is presented consistently and logically. The illustrative material is easy for understanding. The manuscript discusses important and actual problems of current water use. The material may be useful for specialists in various fields of science, economics, industry, and agriculture. Some material may be used in the future as educational material for students and schoolchildren. My recommendations: 1) please, explain the choice of colors and the sizes of the blocks in Figure 1 (right one); 2) minor corrections are required through the text (see the attachad file); 3) the text in sections 2 and 3 presents new methods and new data which I would like to see in the Conclusions and Abstract sections; 4) the Conclusions section requires some revision and I recommend you to shorten the text slightly and to present the main specific results more briefly. In general, I believe that the article can be published in the Sustainability journal (MDPI) after minor revision.

Comments for author File: Comments.pdf

Author Response

Thank you for your time and thoughtful review. Your insightful comments have helped us improve the clarity and impact of our study. We appreciate your valuable feedback and the opportunity to refine our work. We now provide our responses to the comments:

Comment 1: "Please, explain the choice of colors and the sizes of the blocks in Figure 1 (right one)."

Response 1: Thank you for pointing this out. We agree with this comment. We acknowledge that the original figure could be complex to interpret, so we have revised Figure 1 to provide a clearer representation of Gavà’s location within Spain. Additionally, we have improved the differentiation of the municipal structure and its land-use divisions to enhance readability and facilitate a better understanding of the figure.

Comment 2: "Minor corrections are required throughout the text (see the attached file)."

Response 2: Thank you for your careful review. We agree with this comment. We have thoroughly reviewed the manuscript and implemented all the suggested corrections to improve clarity, readability, and consistency.

Comment 3: "The text in sections 2 and 3 presents new methods and new data, which I would like to see in the Conclusions and Abstract sections."

Response 3: Thank you for your insightful suggestion. To address this point, we have incorporated a reference in the Abstract to emphasize the methodological advancements related to grey water footprint calculations for livestock facilities. Furthermore, the Conclusions section has been refined to explicitly acknowledge these developments within the RWF framework, ensuring that the study’s key contributions are clearly highlighted.

Comment 4: "The Conclusions section requires some revision, and I recommend you to shorten the text slightly and present the main specific results more briefly."

Response 4: As mentioned in the previous point, we have revised the Conclusions section to better highlight the key advancements of the research while ensuring a more concise presentation of the main findings. Additionally, adjustments have been made to the Discussion section to provide a more complete and structured analysis of the results and their implications. These modifications improve the clarity and impact of the study while maintaining a balanced and informative approach.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This study presents a comprehensive regional water footprint analysis for the city of Gavà, providing valuable insights into water consumption patterns across multiple sectors. The methodology integrating real water demand data with water footprint calculations is innovative and has potential for wider application. Overall, this is a strong study with important contributions to the field of water footprint analysis at the municipal level.

 

To further strengthen the paper:

 

·      Expand the discussion section to more thoroughly analyze the implications of the findings, particularly in relation to urban planning and water resource management.

·      Provide more context on how this approach compares to or improves upon previous regional water footprint studies.

·      Elaborate on potential policy implications or recommendations based on the findings.

·      Consider adding a limitations section to address any constraints of the study.

·      Proofread for minor grammatical and language issues to improve overall clarity.

 

Author Response

Thank you for your time and thoughtful review. Your insightful comments have helped us improve the clarity and impact of our study. We appreciate your valuable feedback and the opportunity to refine our work. We now provide our responses to the comments:

Comment 1: "Expand the discussion section to more thoroughly analyze the implications of the findings, particularly in relation to urban planning and water resource management."

Response 1: We have revised the discussion and restructured it to better highlight the advancements of this methodology and its potential implications for municipalities and water managers. The updated section now emphasizes how the application of the RWF framework can support urban decision-making, improve water resource allocation, and enhance sustainability strategies at the local level.

Comment 2: "Provide more context on how this approach compares to or improves upon previous regional water footprint studies."

Response 2: We agree with this comment and, in line with other reviewers' suggestions, we have expanded the discussion on previous regional water footprint studies to provide a broader contextual background. This addition highlights how our approach builds upon and advances existing methodologies by integrating a multi-sectoral perspective and refining grey water footprint calculations. The revised text can be found on line 65 of the manuscript.

Comment 3: "Provide more context on how this approach compares to or improves upon previous regional water footprint studies."

Response 3: We have revised the discussion to better address how this methodology contributes to solving seasonal planning challenges and provides a forward-looking perspective on climate change scenarios. By integrating a multi-sectoral approach and refining the representation of temporal variations in water demand, this study enhances the applicability of RWF in decision-making processes.

Comment 4: "Consider adding a limitations section to address any constraints of the study."

Response 4: We believe that the Discussion section adequately addresses both the limitations of the methodology and the advancements required to enhance its representativeness for real-world territorial conditions. The revised discussion elaborates on aspects that need further refinement, such as the incorporation of more detailed livestock discharge data, the adaptation of monthly water footprint assessments, and the integration of GIS tools for spatial analysis.

Comment 5: "Proofread for minor grammatical and language issues to improve overall clarity."

Response 5: We have carefully reviewed the manuscript to refine the formatting and language, ensuring that it is clearer and more appropriate for publication. Minor grammatical and typographical errors have been corrected to enhance readability and consistency throughout the text.

 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors of the manuscript entitled "Regional water footprint for a medium-size city in the metropolitan area of Barcelona: Gavà" aims at developing the first comprehensive RWF analysis that considers the main economic and social sectors at the municipal level. It is an important topic about effective urban planning. However, the authors have only been partially successful in achieving their objectives. In fact, I have a few comments, all of them major. 

1. The specific applicability of external models (e.g. CROPWAP 8.0, WFN database) to the City of Gavà has not been fully discussed. For example, do the input parameters of the CROPWAT model (e.g., climate, soil data) match local conditions? It is recommended to supplement the discussion of the local applicability of the model, for example by verifying the influence of key parameters (such as evapotranspiration coefficient) on the results through sensitivity analysis.

2. Failure to specify how the "indirect water footprint" in the agricultural sector, such as imported feed, is deducted may result in double counting or underestimation. Clarify the calculation logic of the "indirect water footprint" in the method section, and provide examples (such as formula derivation or data adjustment steps).

3. The water footprint distribution map in Figure 4 lacks illustration and color differentiation.

4. The effect of reclaimed water on reducing the blue water footprint (232,038 m³) was not proportionate to the total agricultural water footprint (3,741,447 m³), weakening the strength of the policy recommendation.

5. The lack of comparison with similar studies (such as the regional water footprint of other Mediterranean cities) leads to a lack of innovation and diversity.

6. Supplementary materials (Supplementary table 1) are not sufficiently cited in the body.

7. Recommendations to manage grey water footprints (such as pollution from agriculture and livestock) are too general and lack specific measures (such as wastewater treatment technologies or policy incentives).

8. Among the keywords, "Water footprint" appears repeatedly. It is suggested to delete the repeated keywords.

9. While the introduction mentions global warming and water management, it lacks a specific background on Gavà. It is suggested that geographical, economic and climatic background information of Gavà city be included in the introduction so that readers can better understand the background of the study.

Author Response

Thank you for your time and thoughtful review. Your insightful comments have helped us improve the clarity and impact of our study. We appreciate your valuable feedback and the opportunity to refine our work. We now provide our responses to the comments:

Comment 1: "The specific applicability of external models (e.g., CROPWAT 8.0, WFN database) to the City of Gavà has not been fully discussed. For example, do the input parameters of the CROPWAT model (e.g., climate, soil data) match local conditions? It is recommended to supplement the discussion of the local applicability of the model, for example, by verifying the influence of key parameters (such as evapotranspiration coefficient) on the results through sensitivity analysis."

Response 1: In this study, CROPWAT 8.0 was not directly used for modeling. Instead, we relied on the regionalized data for Catalonia provided by the WFN, which is derived from this model. As noted in the Discussion, one of the proposed methodological improvements is to transition towards direct CROPWAT-based calculations using real-time climatic data from a full natural year to enhance the precision of estimations. This advancement is currently being explored in methodological developments applied to other municipalities, aiming to increase the sensitivity and accuracy of RWF calculations.

Comment 2: "Failure to specify how the 'indirect water footprint' in the agricultural sector, such as imported feed, is deducted may result in double counting or underestimation. Clarify the calculation logic of the 'indirect water footprint' in the method section, and provide examples (such as formula derivation or data adjustment steps)."

Response 2: We agree that providing an example would improve clarity. To address this, we have included a specific example in line 189 of the revised manuscript, illustrating how the indirect water footprint from imported feed is accounted.

Comment 3: "The water footprint distribution map in Figure 4 lacks illustration and color differentiation."

Response 3: The color scheme used in Figure 4 follows the standard categorization defined by the Water Footprint Network (WFN), where blue represents surface and groundwater consumption, green indicates rainwater use, and grey corresponds to pollution-related water footprint. This convention ensures consistency with established methodologies and facilitates interpretation for users familiar with the framework. We have decided to maintain this visualization as we believe it remains the most effective way to convey the data clearly and intuitively to methodology users.

Comment 4: "The effect of reclaimed water on reducing the blue water footprint (232,038 m³) was not proportionate to the total agricultural water footprint (3,741,447 m³), weakening the strength of the policy recommendation."

Response 4: We appreciate this observation and would like to clarify that the total irrigation water consumption in Gavà consists of 649,092 m³ of blue water footprint plus 232,038 m³ of reclaimed water, resulting in 881,130 m³. This means that reclaimed water represents 26% of the total irrigation demand, excluding the contribution from green water (rainwater). This percentage highlights the existing contribution of reclaimed water and underscores its potential for further optimization through improved infrastructure and expanded use in agricultural irrigation.

Comment 5: "The lack of comparison with similar studies (such as the regional water footprint of other Mediterranean cities) leads to a lack of innovation and diversity."

Response 5: This comment aligns with observations made by other reviewers, and we fully agree. To address this, we have expanded the discussion on previous regional water footprint studies to provide a stronger comparative context. This additional explanation highlights how our approach builds upon prior research and contributes to the advancement of regional water footprint assessments. These updates can be found in line 65 of the revised manuscript.

Comment 6: "Supplementary materials (Supplementary Table 1) are not sufficiently cited in the body."

Response 6: We have addressed this by expanding the citation of Supplementary Table 1 within the text to ensure clearer reference to its content and relevance to the study.

Comment 7: "Recommendations to manage grey water footprints (such as pollution from agriculture and livestock) are too general and lack specific measures (such as wastewater treatment technologies or policy incentives)."

Response 7: At this stage, the primary objective of the project is not to propose specific solutions but rather to identify and highlight water management challenges that may exist but have not yet been fully detected. The information provided aims to support municipal authorities in recognizing key issues and fostering collaboration with companies, farmers, and urban water cycle managers to develop appropriate operational solutions.

As this falls within the scope of local governance and stakeholder decision-making, we have maintained our focus on presenting the findings in a way that informs and supports future actions rather than prescribing specific measures.

Comment 8: "Among the keywords, 'Water footprint' appears repeatedly. It is suggested to delete the repeated keywords."

Response 8: We agree that the repetition could be redundant. To improve readability and clarity, we have introduced abbreviations where appropriate, allowing for a more concise and streamlined presentation of key terms throughout the document.

Comment 9: "While the introduction mentions global warming and water management, it lacks a specific background on Gavà. It is suggested that geographical, economic, and climatic background information of Gavà city be included in the introduction so that readers can better understand the background of the study."

Response 9: We agree with this comment and have expanded the background information on Gavà in the Introduction to provide a clearer geographical, economic, and climatic context. Additionally, we have included a map in Figure 1 to situate the city within the broader Spanish territory, helping readers better understand the study area in relation to national and regional water management challenges.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Review

Title: Regional water footprint for a medium-size city in the metropolitan area of Barcelona: Gavà

The article deals with an extremely current topic, but it seems chaotic in its structure and requires significant improvements. In addition, there is no appropriate review of previous work in this field (or similar) and discussion with other results. These do not have to be results from Spain, one can also refer to other countries, e.g. with a similar climate.

To facilitate improvements, some important notes are given below.

1. All abbreviations used in the manuscript must be explained (e.g. UWCM, FRW, WFN). Also, the "mysterious" names of institutions should be described (in the first place of occurrence, not after the seventh mentioning them……. cf. Aigües
2. There are dots in the graphs as separators in numbers, and commas in the text – this needs to be standardized. All numbers in the manuscript should be corrected, because at the moment it is totally misleading.
3. The introduction must be definitely expanded. Line 62 – most RWF studies, please exemplified some of them…. Too many references only to the source [7] – are there no other items on this topic and the whole thing is based only on this one textbook? – please add other items. Water footprint is also matched with water use in the each step of the production process of product, please refer to other (more individually) use of water footprint, on the one hand more individual but on the other more often associated with this term.

The background is definitely insufficient. There is no reference to other literature on calculating water footprint in other locations.

4. The structure of the article requires solid organization. Texts concerning the research material are partly in the right place, but also, for example, at the end of the Introduction and at the beginning of the Results. This is unacceptable. Please provide the characteristics of the studied region in the right place. A map with the location of the area is also needed.
5. Please include a real discussion with similar studies, results. Here, the discussion section is off-topic, rather providing information about future research directions than a real discussion;
6. Detailed comments on specific subsections

 

2.2.2.the grey water footprint produced by animal excretions

The animal excretions may contain bacteria, like Escherichia coli. In sanitary engineering, there is a division into grey sewage and black sewage.

Please consider the inclusion of this share and its form; In addition, excretions can be waste.

What specific concentration were used, the source [31-34] is not sufficient form.

This should be given in the table like the previous one because it is one of the innovations of the article.

 

2.2.4. residential meter it is not enough, also there is a problem with losses and it should also be taken into account;

 

2.2.5. Are you sure that industrial activity never use rainwater ?

 

2.2.7. The source about type of accommodation is too less. Please add the table with relevant data and source. Now, this research reminds black box, without sufficient information about input data. And this is the right place to write about it – not Results chapter….

”If the discharge is within the study region, then a grey water footprint would be applied using the methodology established by the WFN

In the case of discharge at sea and considering the WFN methodology, no grey water footprint impact would be observed”

What is the difference between these two above? Please explain in more details the difference.

2.2.9. Theoretical considerations, and what did you do in the research with this? Was it taken into account and how – no information….

Section 3.8. – we are in the section 3.1. this is strange to talk about previous chapters;

“WF per inhabitant shows a consumption of 377.01 litres/inhabitant.day.” How is this data read from the figure???

litres/inhabitant.day – incorrect way of providing the unit;

 

Figure 1 – no information on what it was developed on, no numerical percentage data;

Figure 3 – wasn’t it said at the beginning that only direct will be analysed????

What is grid water? (figure 4)

 

 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Residencial – it is not in English;

 

Author Response

Thank you for your time and thoughtful review. Your insightful comments have helped us improve the clarity and impact of our study. We appreciate your valuable feedback and the opportunity to refine our work. We now provide our responses to the comments:

Comment 1: "All abbreviations used in the manuscript must be explained (e.g., UWCM, FRW, WFN). Also, the 'mysterious' names of institutions should be described (in the first place of occurrence, not after the seventh mentioning them……. cf. Aigües)."

Response 1: We agree that there were inconsistencies in the use of abbreviations, and we have revised the manuscript to ensure that all abbreviations are properly introduced upon their first occurrence. Additionally, we have included a reference to the role of Aigües de Barcelona in the study, clarifying its function and relevance in the context of water management.

Comment 2: "There are dots in the graphs as separators in numbers, and commas in the text – this needs to be standardized. All numbers in the manuscript should be corrected, because at the moment it is totally misleading."

Response 2: We completely agree that there were formatting inconsistencies. We have revised and standardized all numerical formatting in both tables and text to ensure consistency throughout the manuscript. Regarding the figures, the software used does not allow modifications to this specific aspect of visualization; however, we believe that the numerical representation remains clear and understandable both individually and within the overall context of the study.

Comment 3: "The introduction must be definitely expanded. Line 62 – most RWF studies, please exemplify some of them…. Too many references only to the source [7] – are there no other items on this topic and the whole thing is based only on this one textbook? – please add other items."

Response 3: We also agree on the need to expand the explanation of previous regional water footprint calculations. To address this, we have included additional examples of methodologies in line 65, providing a broader context of prior research. Regarding the repeated reference to [7], this is due to the fact that it refers to the WFN methodological manual, which establishes the foundational definitions for all subsequent studies and methodological advancements. As this serves as a core reference for our work, it remains appropriately cited where necessary.

Comment 4: "The structure of the article requires solid organization. Texts concerning the research material are partly in the right place, but also, for example, at the end of the Introduction and at the beginning of the Results. This is unacceptable. Please provide the characteristics of the studied region in the right place. A map with the location of the area is also needed."

Response 4: We have revised the Introduction to provide a more structured and detailed description of Gavà, ensuring that all relevant background information is appropriately placed. Additionally, we have included a map of Spain in Figure 1 to geographically situate the municipality. In the Results section, we have incorporated specific case study data to confirm that the previously developed (and general) methodology is successfully applied in a real-world scenario, reinforcing its validity.

Comment 5: "Please include a real discussion with similar studies, results. Here, the discussion section is off-topic, rather providing information about future research directions than a real discussion."

Response 5: We have slightly reformulated the Discussion section to focus more on previous studies, which are now properly introduced in the Introduction for better contextualization. However, we believe that the Discussion is also the appropriate place to critically evaluate potential methodological improvements that could enhance the effectiveness of the tool. Additionally, we have emphasized its practical applicability within water planning contexts, ensuring that the discussion remains relevant and aligned with the study’s objectives.

Comment on Section 2.2.2: "The animal excretions may contain bacteria, like Escherichia coli. In sanitary engineering, there is a division into grey sewage and black sewage. Please consider the inclusion of this share and its form; in addition, excretions can be waste. What specific concentration was used? The source [31-34] is not sufficient."

Response: We acknowledge that if discharge regulations include bacterial parameters, they should be considered in grey water footprint calculations. However, in the case of Gavà, due to the difficulty in accessing real industrial discharge analytical data, bacterial contamination was not included in the calculations. Instead, our assessment focuses on the primary water quality issues relevant to the region, namely nitrate pollution and organic matter contamination. Regarding specific pollutant concentrations, we recognize that these values vary significantly depending on local conditions. To ensure a more tailored application, we have included this information within the case study exercise, rather than in the general methodology. This clarification has been incorporated in line 323 of the revised manuscript.

Comment on Section 2.2.4: "Residential meter is not enough, also there is a problem with losses and it should also be taken into account."

We appreciate this observation and acknowledge the importance of considering water distribution losses. However, the objective of this study is to reflect the water demand attributed to different sectors, rather than assessing network inefficiencies, which are inherently managed by water utilities and municipal authorities. Water managers and city councils are already actively engaged in monitoring and improving network performance to minimize losses. That being said, we recognize that incorporating a specific metric to evaluate network efficiency could add value to future developments of the methodology. Exploring ways to better integrate this aspect into regional water footprint assessments is certainly an area of interest for further refinement.

Comment on Section 2.2.5: "Are you sure that industrial activity never uses rainwater?"

Response: Yes, we can confirm that, aside from the agricultural sector, there are no industries in the study area that utilize or harvest rainwater as part of their economic activities. In this region of Spain, rainfall levels are not high enough to serve as a significant or reliable water source, particularly for large-scale industrial operations. While rainwater collection may exist at a small scale, it is not a relevant factor in the regional industrial water footprint.

Comment on Section 2.2.7: "The source about type of accommodation is too less. Please add the table with relevant data and source. Now, this research reminds black box, without sufficient information about input data. And this is the right place to write about it – not Results chapter…"

Response: We agree that including the data used adds value to the study. However, similar to the case of livestock water footprint calculations, we believe it is more appropriate to include this information in the case study section (line 371) rather than in the methodology. This approach ensures that the data is contextualized within the specific study area, given that water consumption patterns can vary significantly between regions. Using generalized factors across different territories may lead to misinterpretations, so we consider it essential to present these values in a location-specific manner.

Comment: ”If the discharge is within the study region, then a grey water footprint would be applied using the methodology established by the WFN. In the case of discharge at sea and considering the WFN methodology, no grey water footprint impact would be observed”.What is the difference between these two above? Please explain in more details the difference.

Response: We have refined the paragraph in line 253 to improve clarity and ensure a more comprehensive explanation of the different discharge scenarios. As stated, the impact assessment follows the methodology established by the WFN, which accounts only for the impacts directly affecting the study area. Discharges into the sea are not considered part of the grey water footprint, as they do not impact inland water bodies. Conversely, discharges occurring within the study region are fully accounted for in the RWF. These refinements enhance the readability and consistency of the methodology applied.

Comment on Section 2.2.9: "Theoretical considerations, and what did you do in the research with this? Was it taken into account and how – no information…."

Response: In the Materials and Methods section, we have developed a general methodological framework designed to be applicable across different territories. The specific application of this methodology to the case study of Gavà is detailed in Section 3.8, where we outline how the general framework has been adapted to a real-world scenario. This structured approach ensures that the methodology is both theoretically sound and practically applicable, allowing for replication in other regions while maintaining flexibility for local conditions.

Comment: "WF per inhabitant shows a consumption of 377.01 litres/inhabitant.day. How is this data read from the figure???"

Response: This value is derived from the sum of the three water footprint contributions presented in the figure, divided by the total population of the municipality. The calculation follows these steps:

(6,458,118 m³) / (46,931 inhabitants) = 137.60 m³/cap/year

137.60 m³/cap/year * 1000 L/m³ * (1 year / 365 days) = 377.01 L/cap/day

Comment: "litres/inhabitant.day – incorrect way of providing the unit."

Response: We agree with this observation and have corrected the unit notation to L/capita/day throughout the manuscript to align with standard conventions.

Comment: "Figure 1 – no information on what it was developed on, no numerical percentage data."

Response: We have modified Figure 1 to provide a clearer representation of land use distribution in Gavà, allowing for better visualization of how different sectors occupy the territory. Additionally, we have adjusted the figure to situate Gavà within the context of Spain, ensuring that its geographic location is more evident.

Comment: "Figure 3 – wasn’t it said at the beginning that only direct will be analyzed????"

Response: As discussed in the methodological development, when assigning the livestock sector’s impact, it is essential to analyze the type of farming system—whether extensive, mixed, or industrial—to determine its relative contribution. While the scope of the RWF focuses solely on direct impact calculations, we believe it is valuable to illustrate how the impact is distributed within different livestock contexts. This distinction helps provide a more comprehensive understanding of the sector’s role in regional water consumption and pollution.

Comment: "What is grid water? (Figure 4)"

Response: Grid water refers to potable water supplied through the municipal distribution network, managed by the company responsible for the integrated water cycle. It is not self-supplied by consumers but rather sourced, treated, and distributed by the local water utility to meet domestic, commercial, and industrial demands. To improve clarity, we have included a brief clarification in the manuscript (line 405).

Author Response File: Author Response.pdf

Round 2

Reviewer 4 Report

Comments and Suggestions for Authors

• I still believe that the characteristics of the research area, i.e. the town of Gava, should not appear in the Introduction, because its place is in the Material and methods section;
• Are you sure that industrial activity never uses rainwater? – if you are so sure, please indicate and underline it also in the manuscript;
• Comment on Section 2.2.7: "The source about type of accommodation is too less. Please add the table with relevant data and source. Now, this research reminds black box, without sufficient information about input data. And this is the right place to write about it – not Results chapter…" – I do not agree with the explanation; I as a reader was really confused during reading. It is too late to present this data in the result section;
• Comment on Section 2.2.4: "Residential meter is not enough, also there is a problem with losses and it should also be taken into account." – I do not agree with the explanation, but it is yours study. There is a need to point in the manuscript that the Authors do not take into account losses of water;
• The extension of Introduction and examples of previous studies in other cities is not extended in enough range (concerning contextualization)

Author Response

Thank you for your second review and constructive feedback. We have carefully addressed your comments to further improve the manuscript: 

Comment 1: "I still believe that the characteristics of the research area, i.e., the town of Gavà, should not appear in the Introduction, because its place is in the Material and Methods section."

Response 1: We have followed your suggestion and moved the paragraph describing Gavà from the Introduction to the case study section in Results.

Comment 2: "Are you sure that industrial activity never uses rainwater? – if you are so sure, please indicate and underline it also in the manuscript."

Response 2: We have clarified this point in Section 3.5, explicitly stating that there are no known significant industrial activities in Gavà that utilize rainwater.

Comment 3: "The source about type of accommodation is too less. Please add the table with relevant data and source. Now, this research reminds black box, without sufficient information about input data. And this is the right place to write about it – not Results chapter…"

Response 3: We have addressed this comment by including the specific consumption values used for Gavà along with their corresponding sources in this section.

Comment 4: "Residential meter is not enough, also there is a problem with losses and it should also be taken into account."

Response 4: We have added a clarification in Section 2.2.4, explicitly stating that water distribution losses are not considered in this study, as the methodology is based on billed water volumes.

Comment 5: "The extension of Introduction and examples of previous studies in other cities is not extended in enough range (concerning contextualization)."

Response 5: We have expanded the Introduction to provide a more comprehensive contextualization of the study.

 

Author Response File: Author Response.pdf