Managing Levees in the Modern Age

Abstract

Floodplains have served important functions in human livelihoods for millennia. Early settlements in the United States frequently occurred along waterways due to the many benefits offered such as navigation for transport of goods and supplies, fertile soils in the low-lying floodplain areas for growing crops, and simply access to water for irrigation and household or industrial purposes. Over time, it became commonplace to try and control the nuisance flooding that occurred in these areas through the use of physical barriers such as floodwalls or levees. Today, there are approximately 7000 levee systems identified throughout the United States, and communities continue to become more reliant on levees as an important tool for reducing risk to life and property from flooding (U.S. Army Corps of Engineers (2016) National Levee Database, https://levees.sec.usace.army.mil). However, many of those benefiting from these levees are unaware of their flood risks, either from levee failure or overtopping. Challenges also exist with increased development behind levees and a desire to continue to build higher levees – a phenomenon known as the levee effect (i.e., putting more reliance on the levees’ ability to perform and protect the public, with a potential unintended consequence of transferring flood risk elsewhere). There is an emerging current opportunity to make forward progress toward a unified, national approach to better manage levees and improve how decisions about levees are made while recognizing other floodplain considerations through a National Levee Safety Program.