Urban Impact Assessment and Emergency Response to Flooding in Buenos Aires, Argentina A thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Water Resource Management at the University of Canterbury by Yanina Ferligoj Dr. Matthew Hughes (Primary Supervisor) Dr. Tom Cochrane (Co-supervisor) Department of Civil and Natural Resources Engineering University of Canterbury 2018 ii Abstract The determination of urban resilience and community response to flooding are significant aspects of hazard management and disaster risk reduction. Anticipating hazard impacts is vital to the development of flood mitigation strategies and emergency response planning. Argentina is an emerging economy with high flood hazard exposure, and its capital, Buenos Aires, is one of the most affected areas. Inappropriate disaster response could therefore affect food supply chains, telecommunications and transport systems nationwide. Flood risk areas in Buenos Aires City have been geographically identified. However, flood impacts have not been well considered, and the emergency response capacity of the city has not been evaluated. This research examined flood impacts in Buenos Aires on infrastructure lifelines and critical facilities, as well as on the wider commercial and residential built environment under current conditions, and accounting for projected impacts of climate change. Evacuation dynamics were explored through characterising spatiotemporal population exposure, modelling evacuation routes, and analysing emergency service response areas. Analyses of different sea-level rise and storm return interval scenarios showed clear trends in increasing impacts under increasing hazard intensities; these impacts were ameliorated when flood warnings were applied. Spatiotemporal population exposures developed for evacuation analyses showed increasing impacts under increasing sea- level rise scenarios. Dynamic evacuation analyses highlighted inadequacies in current welfare facilities to shelter evacuees, however modelling suggests that shelter and emergency response can both be improved by increasing the number of facilities. This research contributes to the quantification of impacts on the built environment and associated economic losses, and helps inform disaster response and management. The methodological approach presented here provides an analytical framework for flood impact analyses and evacuation dynamics that can inform other flood-exposed cities globally. iii Acknowledgements I wish to express my gratitude to my supervisors, Dr. Matthew Hughes and Dr. Tom Cochrane, for their support, encouragement and the freedom they offered me to do research in Buenos Aires (BA), my home city, and to try new things in the geographic information system (GIS) field. I am happy to say that I became a competent GIS user because of their guidance and tutoring time. I also want to highlight their support of my attendance at conferences and courses, in particular for letting me attend their risk management class, which allowed me to gain a better understanding of the topic and to realise how useful GIS can be for risk management. Also, Dr. Tom Cochrane invited me to be his GIS assistant in one of his courses to further improve my skills. I wish to thank New Zealand Aid for my master's degree scholarship. I could not have chosen a better place to study water resource and hazard management. I also wish to acknowledge the Waterways Centre, the University of Canterbury (UC) Student Care and the Civil and Natural Resources Engineering Department for dealing with administrative issues. I wish to thank my friends and flatmates in New Zealand, who gave me their feedback on my rehearsal presentations and made my master’s programme more enjoyable. My family and friends in Argentina always encouraged me to pursue a master's degree, even though that meant being away from home, and their long-distance support when I was feeling a bit homesick proved invaluable. iv Table of Contents Abstract .......................................................................................................................................... iii Acknowledgements ........................................................................................................................ iv Table of Contents ............................................................................................................................ v List of Figures ............................................................................................................................... vii List of Tables .................................................................................................................................. x Chapter 1 Defining Flood Hazards ................................................................................................. 1 Context of Study ............................................................................................................................ 1 Literature Review ....................................................................................................................... 4 The Risk Management Process ................................................................................................ 21 Research Aims and Objectives ................................................................................................. 28 Research Approach and Thesis Structure ................................................................................ 28 Chapter 2 Characterising Flood Losses: A Methodological Comparison .................................... 32 Introduction .............................................................................................................................. 32 Study Area ................................................................................................................................ 33 Methods .................................................................................................................................... 35 Results ...................................................................................................................................... 50 Discussion ................................................................................................................................ 76 Research Limitations and Potential Improvements .................................................................. 85 Conclusions .............................................................................................................................. 93 Chapter 3 Evacuation and Emergency Response.......................................................................... 96 Introduction .............................................................................................................................. 96 v Evacuation Planning in BA ...................................................................................................... 99 Methods .................................................................................................................................. 101 Results .................................................................................................................................... 108 Discussion .............................................................................................................................. 126 Research Limitations and Potential Improvements ................................................................ 143 Conclusions ............................................................................................................................ 147 Chapter 4 Conclusions and Recommendations ........................................................................... 149 Conclusions ............................................................................................................................ 150 Recommendations .................................................................................................................. 152 Reference List ............................................................................................................................. 156 Appendices .................................................................................................................................. 171 vi List of Figures Figure 1. Buenos Aires elevation map and waterways. ................................................................. 3 Figure 2. Disaster risk terminology. Risk can be assessed in terms of hazard, exposure and vulnerability (United Nations Platform for Space-based Information for Disaster Management and Emergency Response [UN-SPIDER], n.d). ............................................................................. 5 Figure 3. Flood risk components and influencing factors............................................................... 7 Figure 4. Areas in BA that are exposed to flooding by the La Plata River, or waterlogged by high-intensity rainfall, identified by a river flood model and the local council. .......................... 11 Figure 5. Depth–damage functions in relation to inundation depth (depth in structure) (Nastev & Todorov, 2013). ............................................................................................................................ 16 Figure 6. The risk management process (Standards New Zealand, 2009). .................................. 22 Figure 7. Summary of thesis structure based on the stages