Emergency Road Network Determination for Seoul Metropolitan Area

Round 1

Reviewer 1 Report

The authors present an elaborated approach to the very relevant topic in disaster and emergency response. The approach is developed along the interesting use-case of the city of Seoul. Overall, the approach presented is purposeful and appropriate with respect to the goal of the study. The results appear to be logical in the context of the explanations given.

However, there are some things that need revision or clarification:

• Throughout the analysis, the authors focus on the minimization of traffic flow disturbance by the chosen emergency response roads in the respective network, additionally prioritizing most vulnerable and at-risk zones within the city in terms of e.g. fast accessibility. It appears, that the chosen approach is not including the initial damage done by the disaster, i.e. the earthquake, to the road network itself. Thus, the selected streets in the emergency road network are focused on the vulnerable areas of the city. At the same time, however, this can lead to a collapse in the performance of the emergency road network in the case of an emergency, since a disproportionately large number of roads are not passable.

As this is an inherent potential problem of the emergency road network derived with the actual methodology, this should be strongly addressed in the description of the approach as well as in the discussion of its limitations.

• The derivation and structure of the introduced factors as well as possible states, used metrics or use-case-related values are virtually not given. For example:
  • The authors are listing a number of factors stating that they have different units and weights, although units are not given and weights and the derivation method in AHP are given later. They propose standardization for comparing purposes. This procedure can only be assessed if the relevant information is available. (l. 156 – 170)
  • Degrees and Ratios are relative categories. For a better understanding it would be helpful if the authors would explain their derivation. (ll. 236 – 258)

This complicates the understanding and comprehensibility of the methodology. Additionally, if the SDRI-analysis is quantitative depends very much on the metrics used within the factors. A restructuring of the text considering this issue would be helpful.

• 41: As cited later it is probably a mixture of criterions. You are referring yourself to methods.
• 55: meaning and functions are provided, attributes could be given more extensibly for emergency road networks
• 71: Limited Impact of earthquakes to certain areas: Source and further explanation needed for this assumption as it plays an important role for the results.

Minor issues:

• 10-11: - doubling of determination, management plans are not included in the presented study
• 28-29: Sentence should be reworked for both style and content
• 108: That is obviously true for prioritization, but the meaning of risk factors should be introduced already here.
• 141: Perhaps some background should be given regarding the characteristics, i.e. the used parameters in factors for ground vibration and seismic mutual risk.
• 222-224: The actual impact of these three categories should be given within the text.
• 288-291: The assessment for the level 3 factors is correct, but the prioritization of the experts is not as clear as stated.
• 394: Chugaryeong fault zone needs introduction.
• 8-9: Clarification needed: maximize the use of the golden hour after disaster?

Especially in the beginning there are some issues regarding syntax and proofreading artefacts and grammar. Proofreading is strongly encouraged.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The paper deals with the issue of determination of emergency road network, which would play a very important role in a case of a natural disaster. It would allow for efficient evacuation and move of rescue teams or medical services. The Authors took into account many factors such disaster risk, population exposure, structures vulnerability and abilities of the emergency respond. This a very interesting work, but I have some remarks, which are listed below:

1. Line 67. Did no strong earthquake happen more recently? Do you really need to refer to an historical event in 1518?
2. Line 72. What is the meaning of the term ‘If r = 10 km is applied’?
3. Line 70. Could you add a map of the referred area?
4. Line 115. Could you split references [19-23] and discuss them separately?
5. Could you provide more details about the expert survey? Were the experts’ opinions uniform or some dispersion was observed?
6. You have analyzed the centrality and it is OK. However in a case of events of the unpredictable nature the redundancy of available remedial measures is important as well. So I’m wondering whether the centrality may stand here for the redundancy.
7. Section 4.3 Travel Pattern and Travel Time Changes Due to Bridge Blocking. Why have you selected just scenarios 2 and 3 (with all or 13 bridges blocked)? What were the criteria? Are the considered scenarios the most probable ones?
8. Figure 4. Could you mark the bridges on the Han River in bit more clear way? Mark the blocked and the passable. They are hardly visible when they are visualized as now.
9. What are the practical conclusions of your work – how could the municipal or the government implement them?
10. Only one third of the references are from last 5 years.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The revised paper is a high quality extension in the field of applied research in desaster preparedness.

The authors properly adressed my remarks and clarified questions regarding the methodology, as well as the limitations of the study. The overall quality of the paper improved significantly.

Reviewer 2 Report

Since the Authors have addressed all my comments I have no further remarks