Natural hazards and flooding impacts

Natural Hazard, FEMA -- "Floods"

Natural Hazard: Flooding

Flooding, according to the Natural Disasters Association (2014), "is the most common environmental hazard worldwide." This according to the organization is more so the case given the vast distribution (geographical) of both low-lying coastal areas and river flood plains. Essentially, flooding occurs once an area that was not formerly underwater is submerged as a result of water overflow. According to Ready, a campaign that seeks to empower members of the public on how best to respond to various emergencies, there are various categories of floods (Ready, 2014). While some floods as Ready points out develop slowly, others tend to develop within a relatively short period of time (Ready, 2014). The latter category is referred to as flash floods. Further, while some floods according to Ready could impact a large area, the effect of others could be limited to a neighborhood. Floods have also been categorized as coastal floods and river floods (Natural Disasters Association, 2014). While river floods are in most cases "atmospherically driven, caused by excessive precipitation," coastal floods, on the other hand "are often due to storm surges caused by tropical cyclones or tectonically produced tsunamis" (Natural Disasters Association, 2014).

Causes and Associated Risk

Floods occur due to a myriad of reasons. Broadly speaking, the causes of flooding as Sene (2008) points out could be geotechnical or atmospheric. Geotechnical causes in the opinion of the author include, but they are not limited to, earthquakes, debris flows, or even land slides (Sene, 2008). Atmospheric causes, on the other hand, "include heavy rainfall, causing rivers to flood, sometimes linked to snowmelt and ice-jams in colder climates, and coastal and estuarine flooding due to surge, wave and wind effects, most notably in tropical cyclones, hurricanes and typhoons" (Sene, 2008, p. 8).

Flooding is easily one of the most costly natural disasters mankind has ever known. Hurricane Katrina, in the words of Frank (2012), "brought with it flood waters, the loss of power, little living space left, and a breeding ground for mosquitoes." In addition to affecting the economy negatively, flooding could also have devastating consequences for people and the environment. To begin with, with regard to their effects on people, floods have been known to leave death and destruction in their wake. In addition to disrupting the normal schedules of those affected, floods also leave scores of families homeless and diseased with a wide range of waterborne (and other) diseases and infections. On the environmental front, flooding could in addition to causing the death of plants and other living organisms, also lead to the contamination of entire areas and water bodies. This is particularly the case when chemicals and other materials from a variety of sources, such as hospitals and nuclear plants, are swept away by raging floods and deposited elsewhere.