Evaluation of Flood Risk Management in Japan through a Recent Case

Round 1

Reviewer 1 Report

In my opinion, the manuscript requires minor revision.
Suggestions are provided in the attached file, which is the manuscript .pdf file edited.
There are some comments, as well as typos corrections in words underlined in green.

Comments for author File: Comments.pdf

Author Response

Thanks for your professional comments. All of your points were addressed.

Reviewer 2 Report

This reviewer finds the updates made to be satisfactory and recommends accepting the manuscript.

Author Response

Thanks so much for your professional comments, which improved the quality of the manuscript significantly

Reviewer 3 Report

The main work of the paper is to evaluate the existing flood risk management measures in Japan, but some problems are lack of in-depth analysis, for example, what are the rules of the inundation range and depth distribution? Why do all shields close to residential areas fail, and why a large number of residents living within a certain distance of the river course did not evaluate as constructed, etc.

The paper puts forward a so-called framework for vulnerability management, but it is more like a guideline, not innovation, and not operability. For example, through better land use planning and regulation, E and S2 can be reduced, but how to do it? On the contrary, some measures need to be improved, but the author does not point out, such as the multi-channel release and timely update of disaster information, the improvement of the government's response ability and post disaster reconstruction ability, etc.

In addition, there are some small problems that need to be modified.

1. It is necessary to simplify “Introduction”.
2. In line 135, Figure 1 should be Figure 2, and the following figure numbers are all wrong.
3. It is suggested to add coordinate and scale in Figure 2, and coordinate in Figure 3, figure 8 and figure 13.
4. The title of Figure 3 may be wrong, in which figure (b) is not the map of 100 years ago, and it is better to keep the same range between figure (a) and figure (b), so as to make a better comparison, and necessary legends should be added to figure (b).
5. It is suggested to modify the name of Figure 6, because the inundation area and different risk areas are not seen from the figure, but only the house distribution in different elevation. The elevation can be re classified according to different risks.
6. It is suggested to add units to the horizontal ordinate of Figure 9, and analyze the figure in this paper.
7. There is no necessary legend in Figure 13, and it can not be seen from the figure that there is any difference in geographical location between the useful and the failed shelters. It is suggested to add some other contents appropriately, such as the distribution of rivers and inundated areas.

Author Response

Thanks for your professional review work

Author Response File: Author Response.docx

Reviewer 4 Report

Dear Authors,

the paper presents a research of understanding flood protection processes on example study area located in Japan. The topic can be considered interesting and original - in research case study of Typhoon flood event were investigated; combine with local and government documents and procedures, all integrated in new conceptual vulnerability reduction framework proposed. Research have a potential practical application on areas where high intensity rainfall events eg. from typhoon. In my opinion presented in paper conceptual model (with strong case study analyses) is a new part in scientific impact of state of knowledge.

Paper have only one weakness – describe of Materials and Methods – please add more information – see below.

I add some comments on different lines of the document.

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Line 57: “Flood Fighting Act” please add reference.

Line 64: Please change “mm/hour” to “mm h-1”

Line 64: “Safety Plan” please add reference

Line 99: Can you add more information about Typhoon No. 19, it means eg. precipitation? It will be show how “big” was the typhoon.

Line 104-108: Number of people died demolished houses, etc. were from flood reason or from other causes? Please complete information.

Line 138: Please change “,” to “ “(space) in “11,900” and throughout manuscript

Line 141: Please change “m3/s” to “m3 s-1” and throughout manuscript

Line 141: What is annual discharge in described gauging station, it should be worth to note it in ms.

Line 152: “974,000,000 JPY” please consider to change to USD

Line 172: Figure2: Please change color of catchment boundary – should by red; scale bar and north arrow is missing – please add; describe name of the Sea; also please add small map with all Japan to show study area.

Line 199: “we investigated the levee structure, you not describe what kind of research you conduct, please add more information.

Line 200: “we… land use along the river course” what kind of classification you use? It was government data or you collect it? Please add more information. And the rest of the metods…

Line 201: “Geographic Information System (GIS)” what kind of software you used? What kind of analyses and tools you use? Please add more information.

Line 202: “map surface elevation distribution, land use, building distribution and shelters in the affected district” what kind of analyses you prepare? Elevation – what kind of topographic numerical model you use? What resolution? It was your data? Land use – look on Line 200 – add more information.

Line 235: Figure 2: Can you have and hydrographs? Because figure data with only max. water depth while flood you can also present in text or table.

Line 237: “186 mm/48h” I suggest to change “186 mm in two days”

Line 275: Figure 3. First of all, please add two maps (a and b) in the same scale! Change a description “Current landform” to year of the map – see reference, and b) to only “1967”; add reference (source) of the map/data! I don’t see “waterways” color on b map? Maybe please change symbol to dot or line? And all remark to figure – legend is missing! I don’t know what color means? Can you unique a and b map?; add North arrow.

Line 282: “Naganuma district, varied from 1m to 2.4 m shown 282 in Fig. 5 as” water damming while flood, especially in urban areas, is related mainly to local conditions (damming by bridges, houses, etc.) and I suggest add information that local damming while flood measured in Naganuma district was varied…

Line 311: Please change “Source: Nagano City)” to “[]” – reference.

Line 325: I suggest delete blue arrows, and add small points on map (a and b) and describe pictures – will be more professional :)

Line 326: Please change “Source: Geospatial Information 326 Authority of Japan)” to “[]” – reference.

Line 329: “building inventory database of the Geospatial Information Authority of Japan” – please add reference in [].

Line 331: “surface elevation in the district” – please add reference.

Line 356: “elevation relative to water level” you want to write “network base level”?

Line 372: Add to description of the figure reference – see above. Please add less decimal places in DTM legend; “Risk zones” are from government / local documents, or you describe it? Why this kind of ranges?

Line 373-397: Can you combine Figure 7 and 8? Please thing about it.

Line 399: “Act on Special Measures concerning Urban Reconstruction,” – please add reference.

Line 424: Figure 9: Please add location of “Tategahana” gauging station to Figure 1; It is water level or water stages in m a.s.l? Please change Time (in hours) to dates of Typhoon No. 19, do you have this data?

Line 447: “recent study [34] indicated that peak flood stages could be decreased by 13–34 cm after the clearance of invasive plants.” Even more, please add more reference about influence of trees on floodplain while flood.

Line 510: Sentence “We interviewed 11 local residents, chosen at random, which revealed that ten of them had insurance of one type or another.” Should be shifted to M&M.

Line 533: Please add year of “Great East Japan earthquake,”

Line 535: “Extreme Disaster Act and the Large-scale Disaster Recovery Act” – please add reference.

Line 570: “Flood warning system of Japan” please add source?

Line 611: Please add on Figure 13 – map with small scale with study area, it will be better show what kind of scale you describe.

Line 655: Please describe on Figure 14: indicators: S, E, C; suggestion: maybe change X axis to “time”?

Kind regards

Author Response

Thanks for your professional comments, which are so helpful

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

This reviewer has no additional comments and recommends accepting the manuscript.

Reviewer 3 Report

I'm sorry that you haven't revised many of the suggestions.But at least you should revise the following.

1. There are still a few wrong figure numbers.
2. It is recommended to add latitude and longitude coordinates to the figures.
3. It is suggested to add some other contents appropriately in figure 12, such as the distribution of rivers and inundated areas.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

This reviewer thanks the authors for efforts invested in the preparation of this manuscript. In it, the authors provide an assessment of disaster preparedness and mitigation techniques, with emphasis on floods, for regions of interest in Japan. This is followed with valid propositions pertaining to coping capacity and a simple operational vulnerability management framework. The paper's subject matter is directly pertinent to Sustainability with detailed explanation and analyses of pertinent aspects of their proposed framework.

This reviewer brings to the authors' attention that in Figure 11, some of the labels are in a language other than English; as not to cause any confusion to the reader(s) the authors are encouraged to revise those, but would otherwise recommend accepting the manuscript.

Author Response

Dear Reviewer

Thanks so much for your constructive and professional comments.

The manuscript was revised following your comments.

Best regards

Guangwei Hunag

Author Response File: Author Response.docx

Reviewer 2 Report

SUMMARY

The paper presents a vulnerability analysis in the framework of the flood risk management in Japan, through a case study analysis of a recent severe weather event. The vulnerability assessment is splitted into two component, a non-life.impact vulnerability and a life-impact vulnerability. The response of the population toward the disaster is mainly investigated from an economical point of view, and some considerations about vulnerability machanisms are given in the discussion and conclusion.

GENERAL COMMENT

The proposed analysis is interesting, as well as some findings given. There are some good food for thoughts that would need to be better addressed, and some informtaion needs to be added in the “Introduction” and “Materials and methods” sections. I also recommend to better narrow and deepen the discussion, which is not clear in some points. I am not able to correct the english, but the paper is very understandeable to me and well organized. Please, find specific coments in the attached file.

Comments for author File: Comments.docx

Author Response

Dear Reviewer

Many thanks for your very constructive comments and professional advice, which helped the revision in so many ways. Really appreciate the time and efforts you spent in reviewing this work.

The manuscript was now improved following your comments and suggestions.

Best regards

Guangwei Huang

Author Response File: Author Response.docx

Reviewer 3 Report

Broad comments:

There are some interesting aspects in this paper, however, there are several problems and flaws related to the article structure/organization, the quality of the maps presented and the goals of the research. The paper is organized in a confusing way, interspersing the description and evolution of the flood management measures with results in the study area, which makes reading the article very difficult. The study area, methodology and conclusions are poorly developed. This is essentially a descriptive paper about flood management in Japan and a flood event that affected a specific area, in which few results are presented and with little relevance. Most of the figures do not support the descriptions made in the text. In addition, the figures are constantly presented in Japanese characters, which is unacceptable and reveals a lack of care when presenting an article in an international journal.

Specific comments:

Line 39 - Showa period – dates of beginning and ending.

Line 102 – Error in Hagibis

‘Site description’ should not be included in ‘materials and methods’. Furthermore, this section describes the study area, the triggering rainfall event, the flood event and its consequences. For this reason, another subtitle should be chosen, replacing ‘site description’.

A map that frames the study area is missing.

Line 118 – When you say “exceeding the historical record”, it is worth to provide additional details. What is the rain gauge? Where is this rain gauge located? How far is this rain gauge from the city of Nagano? What is the period of time available with hourly/daily data?

Lines 128 and 129 – Is there any reference for this definition of disaster?

Line 131 – One or more references should be included here.

Line 150 – It should be mentioned what GIS means because certainly not all readers know the term.

Lines 159 to 161 – This last sentence should be placed at the end of the introduction.

Line 165 – Full stop is wrongly placed before “the Meiji period (1868-1912)”.

Figure 3 must be reformulated:

Maps have no scale and no legend (mainly important in figure 3b).

What does the arrow in figure 3a want to mark?

Are there any built-up areas/buildings/infrastructures located in the floodable area?

Line 181 – Asakawa river was never mentioned before on the text.

Line 182 – “More than 100 years ago” is not enough. It must be said what is the exact year of this map.

Line 184 – Comparing both maps in figure 3, there is a change in the morphology of the river channel. Why is there now a curve in this section? It can just be explained by natural reasons or there was an anthropic intervention?

Line 210 – Didn’t you mean 20 meters, instead of 10 meters? Again, the map (figure 4) and the legend is not clear.

Figure 4 – The map has not the same orientation as the maps in figures 3 and 5. This fact makes it difficult to read the map.

Figure 5 – The map does not provide enough detail to take conclusions. It is not even possible to discern the numbers on the scale and to locate the urban areas mentioned on lines 214 and 215.

Figure 6 – The Hoyasu district should be clearly identified in the previous maps.

Line 277 – It should be mentioned how many buildings/houses were affected during the flood event and how many buildings/houses belong to each class of water depth (figure 5).

Line 280 – The JR railyard should be clearly identified in the previous maps, not only in figure 9.

Figure 7 - Elevation should be replaced by water depths in this figure. It would be much more interesting for the purposes of the research.

Lines 345 and 346 – These stations should have been mentioned in methodology section.

Figure 11 – It is not possible to identify the Nagano Prefecture in this figure. Besides that, there is no legend to identify the meaning of the black and blue lines.

Line 379 – Where is the breaching site?

Line 401 – This depends on the dimension of vulnerability (social, physical/structural, economic, environmental, etc.).

Lines 407 to 412 – In my point of view, this is not a real problem. Farmers and/or the government (that even has the capacity to relocate residents from disaster-prone areas) can clean up rivers to avoid aggravating floods.

The between lines 446 to 470 cannot be considered as results, so it should be included here.

Author Response

Dear Reviewer

Many thanks for your very constructive comments and professional advice, which helped the revision in so many ways. Really appreciate the time and efforts you spent in reviewing this work.

The manuscript was now improved following your comments and suggestions.

Best regards

Guangwei Huang

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

I would like to thank the authors for having addressed my comments. In my opinion, the manuscript has quite complete information and the quality is improved. A better understanding of the site and of the event has been provided and discussion enhanced by the new vulnerability equation proposed.

A few lines need to be re-written, as the English was not very clear to me. I propose some better (in my opinion) sentences, to this aim, in the specific comments, in the attached file.

Comments for author File: Comments.docx

Reviewer 3 Report

This paper has improved substantially with the changes made by the authors when compared to the first version. However, in my opinion, the lack of quality in the figures presented compromises the quality of the work: some of the maps has still no scale; water depth is represented in different color scales on two different maps; legends are not presented uniformly throughout the paper, etc.

The authors' answers to my comments also leave a lot to be desired. The authors say: "At present, we don’t have full raw data of the estimated inundation depths". However, water depths are represented in figures 4 and 5. When I say: Lines 407 to 412 – In my point of view, this is not a real problem. Farmers and/or the government (that even has the capacity to relocate residents from disaster-prone areas) can clean up rivers to avoid aggravating floods. The answer of the authors is: "Thanks for sharing your opinion". This is not an acceptable answer to a reviewer' comment!

Finally, I still believe that there are no relevant methodologies and/or findings in this paper, which means that it is of little interest to other researchers, especially if they are from a country other than Japan.