V 



May, 1980 



AUG 2 6 1980 



N. C. 

 Doc. 



COASrtaUCH 



NORTH CAROLINA STATE LIBRARY 



Photo by J. Foster Scott 



Bare, shifting dunes threaten the abandoned Pennys Hill Coast Guard Station 



Dunes: Where the sea and the land mix it up 



Sometimes North Carolina's coast 

 seems like a battleground where people 

 and regulations butt heads almost as 

 regularly as the surf and shoreline. 

 Many of the major skirmishes have 

 been fought over dunes. Property own- 

 ers have been denied building permits 

 over them, off-road vehicles have been 

 barred from them, and millions of 

 dollars have been spent to maintain 

 them. 



What is a dune? It is a lot more than 

 a pile of sand. Dunes store sand from 

 the ocean, provide housing for ghost 

 crabs, offer nesting grounds for log- 

 gerhead turtles and waterbirds, and 



serve as a last hold for beach grasses 

 and sea oats. And, dunes are a flexible 

 buffer between land and waves. 



The clash between dunes and the 

 ocean occurs along a line of scrimmage 

 defended by the primary dunes. 

 Primary dunes, the first large sand 

 ridge back from the beach, are capable 

 of holding off the waves of most 

 storms. In front of the primary dunes 

 are often smaller sand mounds called 

 frontal dunes. These dunes offer less 

 protection from the ocean. 



Usually the interplay between the 

 ocean and the dunes is equal. Each 

 gives and takes a little. But oc- 



casionally, a team of waves and wind, 

 often from a strong storm, comes along 

 that breaks the defense, topples the 

 dunes and rushes landward. 



Sometimes, this defensive 

 breakdown occurs because of holes in 

 the dune line. People cut away at the 

 dunes and its vegetation with their 

 feet, their vehicles and their construc- 

 tion. These holes may allow the ocean 

 to pierce the dune defense on the next 

 high tide or during the next storm. The 

 result can be flooding and erosion 

 behind the dune line. 



Continued on next page 



