What Is A Floodplain?
Floodplains are exactly what they sound like, low, flat areas of land that are adjacent to bodies of water such as rivers, lakes, oceans, or streams, and may be periodically flooded as a result of severe weather, extended periods of rain, or other natural disasters. Different from a floodplain is a floodway, which is often found in rivers, and is the dry zone found between levees. This conveys flood waters and provides excellent areas for bike trails and parkways, namely because it is only periodically flooded.
A river’s floodplain is often viewed as a completely separate entity from the active channel. Floodways are often found as the focus of construction and control, and the fertile and flat floodplain is ususally the target for commerce, agriculture, and residential development.
During and after a major flood event is when floodways and floodplains become apparent. These areas combine to form a complex biological and physical system the provides support for a number of natural resources as well as natural flood management and erosion control. Floodplains also provide a natural filtering system that allows water to percolate back into the ground and replenish the groundwater supply. Once a river has been divorced from its floodplain through the construction of levees and other flood control facilities, these natural built in benefits are often lost, altered, or drastically reduced.
When purchasing a new property, it is important to ascertain whether or not it is located on or near a flood plain, as this may require the purchase of additional insurance coverage from organizations such as the National Flood Insurance Program (NFIP). This is simply due to the increased risk for damage by flooding translating to higher premiums.
Your local emergency management office will be able to provide you with this information, as well as a detailed history of flood activity in your area. Familiarizing yourself with the patterns of the past will allow you to make an accurate determination of exactly what kind of flood problems you may have to deal with in the future.