Simulation of Extreme Hydrographs in Heterogeneous Catchments with Limited Data

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript proposed a novel approach to rainfall-runoff modeling targeting challenges caused by data-scarce, heterogeneous catchments. The study is within the scope of the journal and contains contributions to efficiently capture spatial and temporal variability in runoff generation without the need for extensive parameter calibration. The case study validates its potential for real-world applications in urban flood risk management. However, I suggest major revisions on the issues below for its publication:

1. Please use consistent spacing between paragraphs. Extra spacing was given in Page 3, 6, 7, 12-17, etc.
2. Figure 8: Please improve the quality of the figure by using compass, distance scale, coordinate ticks on map frame, and legends.
3. A more detailed justification of the assumptions, particularly the linear behavior of the system, is needed to clarify their applicability in complex hydrological environments.
4. Discussion on the calibration process, especially for diverse catchments, would strengthen the model’s credibility
5. Model evaluation and comparison should include more rigorous performance metrics such as RMSE.
6. The sensitivity analysis could be expanded to explore a wider range of parameter variations for heterogeneity studies.

Author Response

Dear Reviewer:

Please see the enclosed file.

Kind regards,

The authors.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This study presents a methodology for generating simple hydrographs in heterogeneous urban drainage systems and applies it to a case study in Cartagena de Indias (Colombia). It uses the principles of proportionality and superposition to represent the unit hydrographs of the different sub-basins on which the study basin is divided, a triangular distribution for both the hydrograph for rainfall production and the unit hydrograph for flow transformation, considering only two parameters for their definition, i.e. peak flow and base time. Such methods, together with the determination of the time to peak and the convolution of hydrographs, are both simple and conventional, and so cannot be considered novel. However, in the present study, the authors have derived analytical expressions for the hydrograph and analysed their hydrological effects in theoretical homogeneous and heterogeneous catchments, with general and expected conclusions. Finally, the method is applied to a real case study of a catchment and an event - i.e. the Ricaurte canal on 16 June 2002 - which shows a hydrograph that can be similar to the observed one in terms of peak flow when a 20-minute delay is applied, but with a significant delay in terms of routing time. The topic and approach are considered interesting (as they could be applied to other regions of the world with similar problems) but not relevant, as they are not considered to be really novel. Overall, the paper is well written but lacks novelty and additional test events that could show statistical results. From my point of view, the paper needs to be improved and I suggest a major revision of the manuscript.
A small comment is that the reference list is short and 6, 9 and 21 should be revised.

Author Response

Dear Reviewer:

Please see the enclosed file.

Kind regards,

The authors

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for your revised version.

Please revise the DOIs of some references, as they should not include the "https://doi.org/" initial part. For example, reference [25] should be "doi:10.3390/hydrology12050107" instead of doi:https://doi.org/10.3390/hydrology12050107.