U.S. COASTAL Act of 2012
The Consumer Option for an Alternative System to Allocate Losses (COASTAL) Act was signed into law on July 6, 2012. The purpose of the COASTAL Act is to lower costs to FEMA’s National Flood Insurance Program (NFIP) by better discerning wind versus water damage in the case of “indeterminate losses;” that is, where little tangible evidence beyond a building’s foundation (“slab”) remains for the proper adjustment of insurance claims for homes totally destroyed by a tropical cyclone.
The COASTAL Act requires NOAA to produce detailed “post-storm assessments” in the aftermath of a damaging tropical cyclone that strikes the U.S. or its territories. Using output from a hindcast model (termed the “Named Storm Event Model” (NSEM) by the Act), the assessments will indicate the strength and timing of damaging winds and water at a given location in the area impacted by the tropical cyclone. If the assessment results for the location of a specific “slab” case can be certified by NOAA as being greater than 90 percent accurate, those results will be input into a FEMA-managed formula that considers a variety of factors that may have contributed to structural damage. Based on this formula, FEMA will determine the appropriate loss allocation between wind and water.
The Act further requires NOAA to create a “Coastal Wind and Water Event Database” (CWWED) to provide the public access to “covered data” (the observations collected during the storm to assist with the assessment). The CWWED will serve as the portal through which the gridded post-storm assessment results and metadata will also be accessed by the public.
In meeting the requirements of the COASTAL Act Capabilities Development Plan (CACDP), NCEI, with support from NOAA's Office for Coastal Management (OCM), will identify and evaluate existing coastal elevation datasets, including source data (i.e. lidar surveys) and derivative products (i.e. DEMs). The gap analysis will include assessing the data quality, spatial extent and date of acquisition and/or creation (in the case of DEMs). The comparison of existing modern DEMs with up-to-date available source topographic and bathymetric data will help inform the process of determining area(s) of interest for proposed DEM development. Using the DEM assessment and gap analysis, NCEI will work with the COASTAL modelers to prioritize areas of interest.
Once the area(s) of interest have been decided, NCEI will follow the procedures developed and tested under the Disaster Relief Appropriation for Hurricane Sandy to build the suite of seamless topographic-bathymetric and bathymetric high-resolution telescoping DEMs. The DEMs along the coast will have a spatial resolution of 1/9 arc-second (~3m), and will coarsen to 1/3 arc-second (~10m) further offshore. NCEI will then work with CSDL to develop a strategy for incorporating DEM updates into models.