Investigating the Impact of Recent and Future Urbanization on Flooding in an Indian River Catchment
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1. The essential question of the work is to what extent the floods in the urbanizing area pose a threat in the future. For this, a hydrological model calculates its value and the potential danger of the affected areas.
2. It is a useful approach that the basis of the investigation is not political but a natural unity. The theoretical problem is the joint management of socio-economic data linked to the political unit and natural data that can be linked to the natural units. From now on, data production based on the network can only be estimated results, despite the demanding methods.
3. The problems arise from the severe lack of data, the loosely handled scale, and the use of methods that barely analyze the degree of uncertainty.
4. The basic issue is the increase in flood risk, partly the cause and partly the victim of urbanization. In the test area of 800 km2, its values and confronting them with building complexes is not a realistic undertaking.
5. The results based on 2x2 kilometer square grid data are difficult to handle (it doesn't matter if the grid is 50x50 or 200x200) and if I understand correctly, this is where the data of the hydrological models come from. In my opinion, these average values cover the extreme data. How were the pixel values entered?
6. If we would like to use a hydrological model, is important to predict the land cover data. It is a good idea to use TerrSet for this. Formally, this is fine, but based on data from 2005, 2011, and 2015, the 2100 estimate is problematic (because TerrSet works this way) and political decisions and the integration of changing climate information may be missing (in principle, their inclusion in the Land Change Modeler is possible).
7. I consider the question of scale to be one of the most serious problems. The SRTM data or the data of the received maps (e.g. soil map) have very different data densities, they can only be analyzed with a common scale. This presumably requires less precise data, e.g. in DEM. Eg. the automatic device probably gives this, the 26 and 52-degree or percentage slope angle seems strange, or I don't see the basic data of the LULC, but the precise surface cover data (and not land use) seems unnecessary.
8. Reduction of the growing flood risk (perhaps despite the annual rainfall of 3000 mm, these can be considered flash floods), reconstruction of the traditional vegetation structure, the forest, and water transport management. At the same time, it would have been more appropriate to make the thesis more concise.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis manuscript (sustainability-3005016) tries to perform hydrological modelling using SHETRAN and hydraulic modelling using HEC-RAS, which predicted that an extreme event will produce a 105% rise in flood depth in 2100 compared to 2005. A consequence of this urbanization has been extensive flooding in many locations within the India. Although this study is a complete one, its novelty and contribution to sustainability and flood research needs to be highlighted throughout the manuscript. More detailed suggestions and comments are presented as follows:
- . The title of this manuscript is problematic and confusing, what does it mean by saying "Investing"? I suppose to be "Investigating".
- . It is uncommon that the authors directly mentioned the conditions of the country and what they did in the very first part of the Abstract. Most contents in the Abstract are related to this country only, which lacks broader international implications.
- . The authors mentioned that "only few studies have attempted to attribute changes in the water balance and flooding issues to LULC and associate them with catchment planning", which I do not agree. Some studies have already done so.
- . Actually, the literature review part is really not enough. There are some studies that have considered land use and land cover in flood and waterlogging research. Please refer to below for examples.
Assessing the scale effect of urban vertical patterns on urban waterlogging: An empirical study in Shenzhen, 2024, 107486.
Participatory Framework for Urban Pluvial Flood Modeling in the Digital Twin Era. 2024, 108: 105496.
- . What are the accuracies of the LULC maps of 2005, 2011, and 2015? And why they were taken from different data sources? Are they consistent?
- . The manuscript did not detail how future land use data are obtained in this study. In fact, the landscape-driven patch-based cellular automaton (LP-CA) model helps simulate and predict future land use changes.
- . The authors used the SHETRAN for hydrological modeling and HEC-RAS for hydraulic modeling, but did not discuss the model calibration and verification processes in detail.
- . Although the models predict an increase in flood depths under future extreme events, the study provides few evidence in terms of model validation.
- . Coordination issues between different administrative boundaries is a factor hindering future development of basin responses. However, the authors did not delve into how to overcome this challenge.
- . The feasibility, cost-effectiveness and possible ecological impacts of nature-based solutions were not explored in depth.
- . A comprehensive discussion of flood risk management strategies is lacking. For example, how to combine early warning systems, emergency response measures, disaster recovery and reconstruction to reduce the social and economic impacts of floods.
- . The planning recommendations provided in the manuscript are also too general and lack specific implementation steps.
Comments on the Quality of English LanguageModerate editing of English language required.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsI accept after the correction.
Author Response
Dear Reviewer,
Thank you for taking time and suggesting changes to make the manuscript more readable. We have made some more amendments from the previous version.
Reviewer 2 Report
Comments and Suggestions for AuthorsAlthough this is a revised manuscript, a number of major serious problems remain unsolved. In particular, the reviewer has the following comments and concerns:
- . The authors did not answer what are the accuracies of the LULC maps of 2005, 2011, and 2015.
- . The paper only considers the impact of future land use and land cover changes on floods, but does not fully consider other potential influencing factors, such as climate change, population growth and migration, water resource management. These factors may have a significant impact on flood events and should be considered in the analysis.
- . The MOLUSE plug-in in QGIS is not the current state-of-the-art method for future land use and land cover change modelling.
- . Flood risk management usually involves multiple stakeholders, including government, community, private sector, etc. The article did not consider the views and needs of these stakeholders in the research process, which will affect the effective implementation of the research results.
- . The authors said that they have included the studies suggested in the manuscript. However, I am missing this part in the revision.
- . The study did not conduct a sensitivity analysis of different model parameters or assumptions to assess the extent to which these conditions affect the flood prediction results. Such an analysis would increase the robustness and credibility of the research results.
- . The uncertainty of these scenarios is not fully discussed in the paper. Many factors in the urbanization process (such as policy changes, population migration, economic development, etc.) are unpredictable, which may lead to increased uncertainty in future scenarios.
- . Lack of consideration at the local or community level. Different communities may face different flood risks and challenges, requiring more specific and customized planning strategies.
Comments on the Quality of English LanguageCan still be enhanced.
Author Response
Dear Reviewer,
The response is put together in a document format and is attached here.
Regards,
Corresponding Author
Author Response File: Author Response.pdf
Round 3
Reviewer 2 Report
Comments and Suggestions for AuthorsThe author has thoroughly edited the work and incorporated the points I recommended. I am pleased to accept this research for publication.
Author Response
Dear Reviewer,
Many thanks for taking your time and giving us the suggestions to bring out the best version of this work.
