FIELD SURVEY ON STORM SURGE BY CATASTROPHIC HURRICANE DORIAN IN THE BAHAMAS 2019

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 Hurricane Dorian made landfall in The Bahamas on Sept. 1 2019 and is an extreme example of a common threat to tropical and subtropical coastal regions. With maximum sustained winds clocking in at 295 km/h, Dorian is tied with the Labor Day Hurricane of 1935 as the strongest category 5 hurricane to make landfall in the Atlantic. In The Bahamas, Dorian persisted for over 48 hours (over 24 of which were at category 5 strength) and resulted in catastrophic environmental, economic, and social damage, as well as unprecedented loss of life. Field surveys and data mining including SNS questionnaires were conducted immediately after the storm’s passage in Sept. 2019, and 6 months following in March 2020 in order to understand the storm surge impact. Storm surge magnitude was recorded at 84 points on the island of Grand Bahama. Storm surge inundation was found to be on the order of 8m above sea level, with approximately 70% of the island affected and flow direction was found to be highly influenced by topographical interaction with elevated ridges, creeks, ponds, and canals. Depending on the direction of storm approach and surrounding geography, property lying less than 8m above sea level can no longer be assumed safe.