Hatteras. Because chains of barriers 

 operate as a system, what one island 

 loses another gains. Inlets that separate 

 the islands often are traps for transport- 

 ing sand. 



The barrier islands also can be 

 reshaped during a storm surge when 

 waves wash over the entire island, 

 dumping the sediment as far as the sound 

 side of the island. 



Peterson and Wells are evaluating 

 erosion mitigation methods. They are 

 examining the effectiveness of bulldoz- 

 ing and its impacts on biological 

 resources. Focusing on Bogue Banks, 

 they are studying the impact on shore 

 birds, surf fishes, macroinvertebrates and 

 nesting sea turtles. 



Looking at the Sand 

 Beneath the Surface 



Most people are surprised to learn 

 that sand is not an infinite resource along 

 the coast, says William Geary, professor 

 of geology at the UNC -Wilmington 

 Center for Marine Science. 



He explains that Cape Lookout 

 separates the coastal system into northern 

 and southern provinces, each with a 

 unique geologic framework that results 

 in uniquely different barrier islands and 

 estuaries. He characterizes the coastal 

 system south of Cape Lookout as sand- 

 starved, ancient "hard bottoms." In 

 contrast, the northern province is 

 underlain by younger sediments, 

 comprised of muds, muddy sands, sand 

 and peat deposited during sea-level 

 fluctuations. The barrier islands also 

 differ in orientation to the shoreline, 

 depth and width of the continental shelf. 



Cleary is using high-tech instru- 

 ments to collect data on the offshore 

 geology to explain the impact of recent 

 hurricanes on North Carolina's coast. He 

 wants to determine the role the underly- 

 ing geologic framework played in beach 

 recovery along various shoreline 



segments. Some, with abundant sand- 

 sharing systems, recovered through 

 natural processes. 



However, many severely impacted 

 areas are now at even higher risk due to 

 the historical sand loss produced by the 

 storms. He says that millions of cubic 

 meters of sand were transported beyond 

 offshore barriers, or onto the shoreface — 

 most of which is permanently lost to the 

 natural rebuilding system. With less sand 

 available, the shoreline recedes. 



The results of Geary's research will 

 help determine the availability of 

 sediments suitable for future beach 

 renourishment projects. His results also 



will help agencies such as the N.C. 

 Division of Coastal Management refine 

 their management strategies in light of 

 shoreline differences. 



Looking for 

 Effective Remedies 



Some scientists have adopted a "let 

 nature take its course" position in dealing 

 with beach movement. Stan Riggs, East 

 Carolina University geology professor, 

 recently told a state legislative committee 

 that urban-style development is no match 

 for the dynamic nature of barrier islands. 

 He warned that a Category 4 or 5 



Atlantic Beach received sand from the Morehead City port dredging in the mid-1990s. 



COASTWATCH 19 



