FLOOD06186 - Laserfiche WebLink

Home Browse Search

Mitigation Strategy Report FEMA-1134-DR-NC State of North Carolina Division of Emergency Management The torrential rain accompanying Fran coupled with pre-existing conditions caused widespread and record-breaking riverine flooding. According to the United States Geological Survey (USGS), rainfall in early September exceeded one foot in several locations. Floodwaters in Raleigh reached their highest levels since 1973. The Neuse River Basin experienced some of the most severe and prolonged flooding. At Goldsboro, peak water levels were measured by USGS at 12,2 feet above flood stage. Fran was moving northward at less than 20 mph when it made landfall on the North Carolina coast. Although the center passed over the Cape Fear area, the radius of winds extended over much of the North Carolina coastal areas, including Brunswick, New Hanover, Pender, Onslow and Carteret counties. At landfall, the minimum central pressure was estimated at 954 Mb [millibars] and the maximum sustained surface winds were estimated at 115 mph (weather surveillance radar at Wilmington, North Carolina, measured winds in excess of 135 mph aloft as the inner convective bands approached the Cape Fear area). Wind damages varied along the storm track, The most significant wind related damages occurred along the coast. As the storm moved inland, most damages were caused by trees falling on homes, businesses and other structures. While hurricane force winds often decline rapidly as a storm moves over land, Hurricane Fran sustained fairly high winds across the State. For example, wind gusts of up to 69 miles per hour were measured as far inland as the Raleigh-Durham Airport, These winds caused trees to fall on more than 4,000 structures. Hurricane Fran produced a coastal storm surge that was measured at heights of up to 12 feet. The storm surge caused flooding as far north as the Pamlico River. Stillwater surge heights reached five feet at South port and the Town of Beaufort, respectively. The areas most severely impacted by storm surge were the coastal barrier islands, including Pleasure Island, Shell Island, Topsail Island, and Bogue Island. These areas were not only hit hard by the surge and heavy waves, but also experienced the highest winds, North Topsail Beach was devastated by the surge which included breaking waves reaching heights of over ten feet. Structures constructed to pre-1985 building standards, including those which were not built on elevated, reinforced piers, frequently collapsed due to the combined effects of erosion, flood loads and/or impact with debris. Collapsed structures contributed to the large quantities of debris, which when carried by storm surge, significantly affected adjacent and landward structures, Hurricanes Bertha and Fran dramatically redefined the shore line and protective dune system, thereby further exposing already vulnerable coastal communities to future storms. Varying levels of dune and beach erosion occurred from Kure Beach to Atlantic Beach, causing the loss of vegetation and changes in the mean high water line. Changes in the established vegetation line may reduce the size of buildable lots along the shore. For those buildings that were substantially damaged, rebuilding may not be allowed under Coastal Area Management Act (CAMA) setback requirements. . Hurricane Fran, while causing extensive damage, was by no means catastrophic. A Category Five storm, with winds exceeding 155 miles per hour and a potential storm surge above 18 feet, would cause a level of destruction significantly higher than that which was experienced during Hurricane Fran, Thus, it is incumbent on those who seek to rebuild to do so in a manner that makes North Carolina less susceptible to damages following the next hurricane. Page 4