Urban Coastal Flood Vulnerability in Ecuador 1 Full Title
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Urban coastal flood vulnerability in Ecuador 1 Full title: A participatory community case study of periurban coastal flood 2 vulnerability in southern Ecuador 3 4 Short title: Urban coastal flood vulnerability in Ecuador 5 6 Erica Tauzer1*, Mercy J. Borbor Cordoba2, Jhoyzett Mendoza3, Telmo De La Cuadra3, 7 Jorge Cunalata4, and Anna M. Stewart-Ibarra1,5* 8 9 1Institute for Global Health & Translational Science. SUNY Upstate Medical University. 10 Syracuse, NY, USA. 11 2Facultad de Ingeniería Marítima y Ciencias del Mar, Escuela Superior Politecnica del 12 Litoral (ESPOL). Guayaquil, Guayas Province, Ecuador. 13 3National Service for Risk Management and Emergencies. Guayaquil, Guayas Province, 14 Ecuador. 15 4Universidad Tecnica de Machala. Machala, El Oro Province, Ecuador. 16 5Department of Medicine, SUNY Upstate Medical University. Syracuse, NY, USA. 17 18 *Co-corresponding authors: 19 Erica Tauzer; Email: [email protected] 20 Anna M. Stewart-Ibarra; Email: [email protected]; 1 Urban coastal flood vulnerability in Ecuador 21 Abstract 22 Background: Populations in coastal cities are exposed to increasing risk of flooding, 23 resulting in rising damages to health and assets. Local adaptation measures, such as early 24 warning systems for floods (EWSFs), are urgently needed to reduce the risk and impact 25 of flood events. The aim of this study was to assess community perceptions and self- 26 reported actions in response to flooding in a tropical coastal city to inform flood risk 27 reduction policies and programs. 28 Methods: This qualitative case study was conducted in flood-prone areas in Machala, 29 Ecuador, a coastal city exposed to seasonal floods and extreme floods during El Niño 30 events. Adult community members from three periurban sites were invited to participate. 31 Focus groups discussions (11 focus groups in total) were held with community members 32 (n=65 people) from September to November 2014 to assess perceptions of flood 33 exposure, sensitivity, adaptive capacity, and current alert systems. Focus groups 34 discussions were audio recorded, transcribed, and coded by topic; participatory maps 35 were field validated, georeferenced, and digitized using GIS software. 36 Results: Community members identified the presence of annual flooding during the rainy 37 season, as well as greater than normal flood events (depths ranging from 0.5 to 3 meters), 38 which recurred every 3-4 years in some communities. The deepest floods occurred during 39 the 1982 and 1997/1998 El Niño events. Community members perceived that exposure to 40 flooding depended on the rainfall coinciding with high ocean tides, and geographic 41 proximity to blocked drainage areas, canals, and low local elevation. Participants reported 42 that children were the most sensitive group due to increased susceptibility to skin 43 infections and mosquito borne diseases (i.e., dengue fever). Other sensitive groups 2 Urban coastal flood vulnerability in Ecuador 44 included the elderly, physically handicapped people, low-income families, and recent 45 migrants. They identified persistent social-ecological vulnerabilities that increased flood 46 risk and exposure in the urban periphery, such as inadequate access to garbage collection, 47 homes settled in precarious low-lying geographies, economic barriers, lack of political 48 access, and lack of social mobilization. In addition, communities expressed a lack of 49 social capital (e.g. political voice), despite the existence of formalized community 50 councils. Key neighborhood resources with respect to flooding included green areas, 51 schools, nurseries, fire stations, health clinics, police stations, a retention wall (berm), and 52 an emergency meeting place. Challenges for adaptive capacity existed primarily in 53 actions related to the preparation and recovery stages of flooding. Despite the presence of 54 an official flood warning system, community member relied on informal communication 55 channels via social media. 56 Conclusions: The flood vulnerability assessment framework and participatory research 57 process utilized here can potentially inform studies in other flood-prone regions to guide 58 the development of EWSFs and other climate change adaptation policies and actions. 59 60 Author summary 61 Flooding is a major concern in coastal cities, causing damages to people’s health and 62 property. Many countries have identified the need for early warning systems for floods 63 (EWSFs) and other actions to reduce the impact of flooding. However, it has been 64 challenging to implement these systems without an understanding of the local social- 65 ecological context, including people’s perceptions and experience with flooding. In this 66 case study, we explored community perceptions of flooding in high-risk urban 3 Urban coastal flood vulnerability in Ecuador 67 neighborhoods in southern Ecuador. Homes were at greatest risk of flooding if they were 68 located near clogged drainage canals, low-lying properties, and flood-prone canals. 69 Children were most affected by flooding, due to the risk of infectious diseases. 70 Communities had difficulty preventing floods and recovering from floods due to factors 71 such as lack of leadership, lack of social mobilization, limited household finances, and 72 lack of coordination with local government authorities. Despite an official EWSF, 73 community members reported using social media and other informal communication 74 channels to receive local flood alerts. Based on these findings, we identify key 75 considerations to improve EWSFs. 76 Keywords: flooding, vulnerability, climate, adaptation, early warning systems, Ecuador 77 4 Urban coastal flood vulnerability in Ecuador 78 Introduction 79 Damages due to flooding are increasing in urban areas [1,2] due to increased 80 population and assets, a changing climate [3], coastal subsidence [4–6], and deforestation 81 [7,8]. Global flood losses in coastal cities are projected to increase from $6 billion per 82 year in 2005 to $52 billion a year by 2050 [9]. When damages due to sea-level rise and 83 coastal subsidence are included, costs in large coastal cities across the world are 84 estimated to reach $1 trillion a year in the absence of adaptation measures [9]. 85 In Latin America and the Caribbean (LAC), 7.5 million inhabitants and $299 86 billion USD in built capital are exposed to flooding from a 100-year event, without 87 considering hurricanes [10]. This exposure will increase to 8.8 to 9.9 million inhabitants 88 by mid-century, when taking into account extreme sea levels, increasing populations, and 89 the historical trend in storm activity [10]. Flooding presents a high social and economic 90 burden, particularly in low-income vulnerable populations – those who are least able to 91 cope with the impacts and recover from the damages of flood events. 92 To address flooding and other disasters, the global Sendai Framework for Disaster 93 Risk Reduction (2015-2030) identifies understanding disaster risk as a top priority [11]. 94 This understanding should encompass the multiple dimensions of vulnerability, capacity, 95 exposure of persons and assets, hazard characteristics, and the environment. A better 96 understanding of local community perceptions of flood hazards can inform risk 97 management planning that aims to reduce exposure to flood events while strengthening 98 the resilience and adaptive capacity of communities (i.e., Sendai Framework priority #3) 99 [11,12].This understanding can inform the development of tailored climate services for 100 disaster managers, such as early warning systems for floods (EWSFs) [11,11,13,14]. 5 Urban coastal flood vulnerability in Ecuador 101 Early warning systems are integrated systems of surveillance, forecasting, and 102 prediction of threats; assessment of disaster risks; communication of activities, systems 103 and processes; and preparation that allow people, communities, governments, companies 104 and other interested parties to take appropriate measures to reduce disaster risks in 105 advance of hazardous events [15]. In the United Nations Climate Change COP15, sixteen 106 of the 21 Latin American countries listed the improvement and establishment of early 107 warning systems for climatic events, including floods, as a priority. When implemented 108 effectively as part of a comprehensive risk management plan, a well-designed EWSF 109 increases community and ecosystem resilience, reduces vulnerability and reduces 110 damages to economies, health, property, infrastructure, and other assets of people, 111 communities, nations, and the private sector [16,17]. 112 Coastal Ecuador is particularly vulnerable to flooding due to an extensive, densely 113 populated coastline along the Pacific Ocean [10]. One in thirteen people (7%) in the 114 country live below 5 meters of elevation. Coastal Ecuador experiences severe floods 115 during El Niño events due to strong teleconnections that increase local rainfall, as 116 observed in 1997-1998, and 2016 [18,19]. A recent study identified coastal Ecuador as 117 the highest coastal risk location in LAC due to a combination of coastal hazards, 118 geographic exposure, and socioeconomic vulnerability [20]. When flood costs are 119 measured as percentage of GDP, the coastal city of Guayaquil (population 2,644,891, 120 [21]) ranks as the 3rd most vulnerable city to flooding worldwide [9]. In these coastal 121 cities, unstructured rapid urbanization has pushed the poor into low-lying areas along 122 estuarine waterways prone