A megacity is a metropolitan area with a total population of more than 10 million people. The definition was expanded by Spanish sociologist Manuel Castells in response to economic and social shifts. Castells defines megacities as large urban areas in which some people are connected to global information flows while others are disconnected and information poor (Marolla, 2016). Natural and man-made disasters are the cause of loss of life, financial collapse, and migration and public health risks among other issues.