What area is referred to as the base floodplain?

The base floodplain is defined as an area that is subject to flooding during the base flood, which is commonly understood as the flood event that has a 1% chance of being equaled or exceeded in any given year. This area is critical for floodplain management and is essential for the planning and regulation of land use to minimize flood risks. Understanding this area is vital for making informed decisions regarding development, land use planning, and disaster preparedness.

Areas at high elevation are typically less prone to flooding but are not specifically identified as the base floodplain, making them not relevant to this definition. The zone of actual flood impact refers to the immediate areas where flooding has occurred or could occur during an event, which does not necessarily define the entire base floodplain. A designated flood-free zone is an area that is specifically protected from flood damage through various means, but it does not describe the base floodplain, which is inherently at risk for flooding.