North Carolina Flood Risk Information System
In North Carolina, the state developed a Flood Risk Information System to improve the accuracy and functionality of the state's floodplain maps, and to help local governments and state agencies make decisions about how to reduce flood losses (or mitigate flood risks). The state digitized the floodplain maps developed by Federal Emergency Management Agency (FEMA) using high-resolution LiDAR data for the entire state, and developed this System to make the maps more accurate and easier to use.
This System incorporates additional data layers not included on FEMA floodplain maps - such as flood depth damage information determined from building footprints, parcel information, and first floor elevations. The risk mapping tool allows North Carolina communities to make better decisions about where to direct new development and how to invest hazard mitigation funds, and complies with FEMA floodplain mapping requirements. It also allows local planners to assess their financial vulnerability by determining what economic damages will be caused by different levels of flooding. It also helps local planners prioritize mitigation options for reducing flood losses.
Although North Carolina’s current system does not include information about sea-level rise or climate change, it is a useful model for states to consider for making flood risk information more easily available to local governments and the private sector. Floodplain maps are important for adaptation because they are used by local governments to determine how to regulate development and how to spend flood mitigation funding.
To develop the system, the state imposed a real estate recordation fee, and combined these state resources with FEMA resources to develop the system. In addition, the digital platform is estimated to save the state 30 percent because it no longer has to redraw physical maps every time new flood data becomes available.
Although the state received funding from FEMA to study how sea-level rise will change the state’s flood risks in 2009, the information from this sea-level rise assessment has not been incorporated into North Carolina's Flood Risk Information System. The sea-level rise study evaluated the state’s risk of flooding under various scenarios of potential sea-level rise (up to 1 meter) over four “time slices” through 2100, and included consideration of how flood risks would change based upon storm intensity and frequency.
The System is being picked up in Virginia, Alabama and Florida. The state of Maryland is looking to develop a similar system that will also incorporate information about future flood risks posed by sea-level rise.
Publication Date: May 19, 2014
- State of North Carolina
- Mapping tool