Understanding Flood Risk

Understanding Flood Risk

June 12, 2018

Identification of water resources, evaluation of risk, and planning for management policy provide the framework for truly understanding the cycle of water and what effect it has on the environment, property owners, and communities. Engineering solutions to address water management play a significant role in the overall education of water. 

Charlie Penland discusses the impact of water and provides an interactive graphic that allows readers to follow the cycle of water and learn more about the effect it has on the environment, property owners, and communities. 

How is flood risk for a particular property defined? Most often FEMA Flood Insurance Rate Maps (FIRMs) are referenced in an effort to answer this question. According to the lines on the maps, a property is “in” or “out” of the floodplain based on its location. However, during extreme event rainfalls, a significant number of flooded properties are often found to be outside of the designated floodplain. Because of the sudden effects brought on by surplus rainfall and the limited scope of floodplain mapping, FIRMs do not have the capability of telling the whole story. So then, how should flood risk be determined?

Each “property,” in however you define “property,” has unique flood risks based on a multitude of flooding sources. This can include both natural and man-made occurrences. Developing an understanding of how water drains to and from a property is important in determining these risks. It is helpful to know the history of flooding and how to look for information that might indicate risk. Every region has its own unique ways of handling and quantifying drainage. For example, what is considered natural street drainage in one community might be considered as a significant flood in another. It is important to have a resilient strategy associated with flooding to know what can take on water and recover with little or no damage or costs, and what can be effectively protected from water where that protection is more cost effective than the cost of recovery after a flood.

A key element of flood events is that they teach us different lessons each time, but sometimes we fail to recognize those lessons.

Flood risk is one of the most difficult things for property owners to comprehend. The damage that water can cause can be both devastating and demoralizing. A key element of flood events is that they teach us different lessons each time, but sometimes we fail to recognize those lessons. When these events happen, there is only a small window of opportunity to evaluate risk and take steps to put a plan of action in place before interest in doing so begins to fade.

 This text was originally published in Walter P Moore's 2018 Stewardship Report.