Coastal flood maps represent "snapshots" of flood risk for a local area at the time the study was performed. Flood maps can become obsolete as physical conditions change, or as our understanding of local flooding and flood effects improves. Obsolete flood maps have consequences for life safety (individuals may be living at risk and not know it), insurance reasons (flood insurance premiums may no longer reflect actual flood risk), and for land use and building permit reasons (development, building design, and post-flood recovery decisions are no longer tied to the nature and severity of flood hazards). Thus, it is in the best interest of the community and its citizens to maintain up-to-date flood hazard maps.
New flood studies are undertaken and flood maps are updated for a number of reasons, including:
- Better topographic data;
- A longer period of record to characterize coastal flood events;
- Improved flood modeling procedures; and
- Changes in land use and land characteristics, shoreline erosion, construction of flood barriers, etc.
According to FEMA's records, eight of the top 10 most expensive disasters in our Nation were caused by hurricanes. During these disasters, thousands of homes were destroyed, lives were disrupted, and many people were killed. Understanding coastal risks and then taking steps to make our homes and communities more resilient makes sense both on an economic and human level.