as accomodations are expanded. Fort Clinch State Park occupies a shore 

 frontage of about 4,000 feet immediately south of St. Marys River entrance. 

 The study area extends about 5 miles south of the jettied mouth of St. Marys 

 River to the fishing pier. The Port Clinch State Park beach is backed by 

 high dunes. The shore of the problem area, which begins south of the park, 

 is generally low with residential development immediately back of the berm. 

 The problem is one of gradual erosion of the shore throughout the latter 

 area. This erosion has resulted in damage to roads and buildings as the 

 protective beach was reduced in width. 



The tides at Amelia Island are semi-diurnal, with mean and spring 

 ranges of 5.7 and 6.7 feet respectively. Waves affecting the shore approach 

 principally from the northeast quadrant resulting in southward predominance 

 in direction of littoral drift, as indicated by past accretion at the St. 

 Marys River north jetty. However, reversals in drift direction cause some 

 accumulation of sand in a fillet south of the south jetty. Due to the rela- 

 tively low top elevation and permeability of this jetty sand is carried over 

 or through the jetty into the inlet. 



The District and Division Engineers and the Beach Erosion Board concluded 

 that the most suitable complete plan of protection comprises a protective 

 beach about 13,000 feet long and a groin about 800 feet long near the north 

 limit of the fill. The protective beach with a berm 50 feet wide at elevation 

 11 feet above mean low water would be provided by artificial placement of 

 approximately 300,000 cubic yards of suitable sand for the initial fill and 

 600,000 cubic yards of sand as advance nourishment. Periodic nourishment of 

 approximately 200,000 cubic yards of sand per year would be required to main- 

 tain the widened beach. They made an economic analysis of the foregoing 

 complete plan of protection and found it to be not justified by evaluated 

 benefits. They also considered a partial protection plan comprising construc- 

 tion of one groin and placement of spoil from maintenance dredging of the 

 Fernandina Harbor entrance channel on the beach about 4,000 feet south of the 

 south jetty. They estimated that this plan would involve placement of about 

 120,000 cubic yards of sand annually. Although they believed that this plan 

 would reduce the rate of erosion, they did not evaluate the benefits therefrom 

 which were considered to be relatively small. 



The District and Division Engineers and Beach Erosion Board concluded 

 that the cost of protecting the beach of Amelia Island by either plan exceeds 

 the benefits that could be reasonably expected by a wide margin, and recom- 

 mended that no project be adopted by the United States at this time authoriz- 

 ing Federal participation in the costs of shore protection at Amelia Island, 

 Florida. They further recommended that, subject to their own determination 

 of economic justification, local interests consider adoption of the complete 

 plan of protection comprising beach widening, construction of one groin and 

 periodic nourishment, or as a minimum construct one groin and arrange to have 

 dredged material placed on the beach periodically and pay such costs as may 

 be involved in excess of the costs of disposal by other means. The Chief of 

 Engineers concurred in the views and recommendations of the Beach Erosion 

 Board. 



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