World's 10 Most Flood-Threatened Cities An American city enters the list at No. 6 By Kate Seamons, Newser Staff Posted Aug 19, 2013 9:25 AM CDT Updated Aug 24, 2013 7:20 AM CDT 26 comments Comments Guangzhou, China. (©) (Newser) – It's a gloomy day in the world of flood-related studies. New research indicates that by 2050, coastal flooding could cause $1 trillion in damage—per year. That is if no steps to safeguard these areas are taken. LiveScience notes the $1 trillion figure was reached in both the best- and worst-case scenario projections. On the flip side, preventative measures could drop the damage figure to $50 billion a year. In any case, now might be the time to move to Europe: The list of most at-risk cities is filled with mainly Asian and North American locales. LiveScience presents the top 10: Guangzhou, China Mumbai, India Kolkata, India Guayaquil, Ecuador Shenzen, China Miami Tianjin, China New York, NY-Newark, NJ Ho Chi Minh City, Vietnam New Orleans Click for the next 10 cities on the list, which include two more American locations.