All Floods Are Not Alike
Although it may seem that floods only differ in size and intensity, according to Helen Smith of JBA this is not the case. In an Insurance Thought Leadership post (insurancethoughtleadership.com/how-different-flood-types-affect-risk/) she describes the types and differing affects:
- Fluvial flooding is when rivers (and smaller streams) overflow their banks. (Don’t discount the potential damage from small streams. In 2001 I witnessed how heavy rains caused a small stream in Fort Washington, PA to flood the entire area making the first floor of the building where I worked unusable for months.)
- Pluvial flooding is the result of heavy rains (the flood in Genesis is an example). Typically these floods recede quickly and are cleaner than other types. (Although not mentioned by Smith, these floods could also result in mudslides making cleanup more difficult.)
- Storm surge flooding results from higher sea levels and coastal storms. Saline water makes storm surge flooding extremely damaging.
The same location can be exposed to more than one type of flood, sometimes from the same event. For low lying coastal areas near rivers, a tropical storm with heavy rain and high winds could result in all three types – literally a “perfect storm”.
Present FEMA maps do not provide a complete picture of flood risk, or the interactions between the different types of flood. Organizations need as much information as possible to analyze their flood risk. In case of doubt, they need to include floods and their consequences in disaster planning, and purchase flood insurance as a backup.