Another North Caro- 

 lina lighthouse is being 

 imperiled by a shifting 

 shoreline. The Cape Hat- 

 teras lighthouse, the tall- 

 est in the nation, has 

 signaled navigators away 

 from treacherous waters since 1870, 

 when it replaced an older structure 

 built in 1803. 



But, because of erosion, authorities 

 believe the lighthouse will collapse — 

 some say within 30 years, others much 

 sooner. 



The National Park Service is trying 

 to decide whether to preserve the 

 landmark, either by moving it or arm- 

 ing its foundations against encroaching 

 waters. The park service has enlisted 

 the help of the MTMA Design Group 

 of Raleigh, which is investigating ways 

 to save the building. The design group 

 has asked Jerry Machemehl, an 

 engineer and Sea Grant researcher, to 

 produce plans for protecting the 

 lighthouse. 



Machemehl has studied the waves, 

 currents and storm surges of the 

 shoreline, which he terms a "high- 

 energy" area. The problem, he says, is 

 to formulate a design flexible enough to 

 allow the natural shoreline processes to 

 continue, but solid enough to keep the 

 lighthouse erect. One of Machemehl's 

 designs calls for the construction of a 

 revetment that would encircle the 

 lighthouse and, as the shoreline re- 

 cedes, create a man-made island under 

 the landmark. 



Two alternative plans call for groins, 



beach nourishment and a smaller 

 revetment — all designed to build a buf- 

 fer of sand between the ocean and the 

 lighthouse. 



Machemehl will submit his plans to 

 the park service in January. 



The North Carolina Sea Grant 

 program has received funding for its 

 1980 budget allocations. Sea Grant will 

 receive $1,045,000 in federal funds and 

 $522,500 in state funds. Director B.J. 

 Copeland says this is a 10 percent in- 

 crease over the 1979 funding. Nine new 

 research projects will be initiated, 

 while 21 others will be continued. 



It was an unfamiliar 

 habitat, but 300 coho 

 salmon and 150 rainbow 

 trout weathered eastern 

 North Carolina's hot 

 summer this year. The 

 fish lived in cages in the 

 canals of Texasgulf Inc. on the shores 

 of the Pamlico River near Aurora. 



Sea Grant researchers imported the 

 fish last April for one of a series of 

 aquaculture experiments being con- 

 ducted at the site of NCSU's eel farm, 

 which is headed by Sea Grant associate 

 director Bill Rickards. The eel farm is 

 located on property leased by Texas- 

 gulf to East Carolina University. 



The water running in the Texasgulf 

 canals comes from underground wells 

 in the plant's open pit mines. 

 Naturally, it is colder than nearby sur- 

 face waters. In the summertime, the 



canal water reaches the high 60s, the 

 upper limit of the temperature range 

 tolerated by coho salmon and rainbow 

 trout. 



Researchers found that the fish not 

 only survived the summer, they 

 thrived. Both species grew at a faster 

 rate than they would have in the wild. 

 The trout gained weight at a surprising 

 rate, reaching an average size of one- 

 third pound after six months. Growth 

 of the salmon was less impressive, but 

 still enough to encourage researchers 

 about the possibility of raising more 

 salmon in eastern North Carolina. 



The experiment ended this fall, when 

 most of the fish died from embolisms 

 caused by gas bubbles. The disease was 

 due to mechanical problems with water 

 dispersion in the canals. Rickards 

 thinks that , this problem can be cor- 

 rected when further experiments are 

 conducted with another group of fish 

 next year. 



Coastwatch is published monthly 

 except July and December by the Uni- 

 versity of North Carolina Sea Grant 

 College Program, 105 1911 Building, 

 North Carolina State University, 

 Raleigh, NC 27650, Vol. 6, No. 9, Oc- 

 tober, 1979. Dr. B. J. Copeland, direc- 

 tor. Written and edited by Mary Day 

 Mordecai, Neil Caudle and Kathy 

 Hart. Second-class postage paid at 

 Raleigh, NC 27611. 



COASTWATCH 



105 1911 Building 



North Carolina State University 



Raleigh. NC 27650 



Second-class postage paid 

 at Raleigh, NC 27611 

 (ISSN 0161-8369) 



