PALM BEACH COUNTY. FLORIDA 



(from Martin County line to Lake Worth Inlet and from 

 South Lake Worth Inlet to Broward County line) 



The purpose of the investigation was to determine the most economical 

 method or methods of restoring the beaches and shore property from future 

 erosion. The study area comprises two reaches of shore totalling 29.3 miles 

 on the east coast of Florida from the Martin County line to Lake Worth Inlet 

 and from South Lake Worth Inlet to the Broward County line. A study of the 

 intervening reach was completed in 1957 (B.E.B. Bulletin - Vol. 12, 19S8). 

 The area is centered about 70 miles north of Miami. Parts of the area are 

 extensively developed as winter resorts. The permanent population of the 

 county, about 157,000, is greatly increased during the winter. About 2.4 

 miles of the ocean shore are publicly owned, most of which is used for 

 public bathing beaches. The shore of the study area is exposed to waves of 

 the Atlantic Ocean. To the northeast the fetch is unlimited, but to the 

 east and southeast the incidence of swells is influenced by the shelter 

 afforded by the islands of the Bahama group. The predominance of energy 

 components is such as to produce a dominant southward littoral transport. 

 However, reversals in direction of transport occur, principally in the 

 summer. The mean and spring tidal ranges are respectively 2.8 and 3.3 feet. 

 The two highest tides of record, 11.2 and 8.7 feet above mean low water, 

 occurred during hurricanes in 1928 and 1936 respectively. A tide of 7 feet 

 is considered suitable for design purposes, as a tide of this height could 

 be expected during hurricanes of medium intensity. The only apparent 

 natural source of littoral material to supply the problem areas is the 

 eroding beaches to the north. The accumulation of sand north of Lake Worth 

 Inlet indicates a littoral drift rate of about 230,000 cubic yards annually. 



The District and Division Engineers concluded that the most practicable 

 plan of shore protection consists of artificial placement of protective and 

 recreational beaches. Continued operation of the existing sand-transfer 

 plant at South Lake Worth Inlet and additional periodic nourishment by arti- 

 ficial placement of suitable material from adjacent waterways would provide 

 for stability of the protective beaches. They made economic analyses of the 

 foregoing plan of protection by sections, and concluded that the plans of 

 protection are economically justified for all reaches studied. They found 

 that public benefits justify Federal aid of one-third of the first and 

 periodic nourishment costs for the publicly owned shores, and that public 

 benefits for certain privately owned reaches of shore justify Federal aid 

 for those reaches. 



The District and Division Engineers and the Beach Erosion Board recom- 

 mended adoption of projects for Palm Beach County, Florida to authorize 

 Federal participation in the costs of the plans for protection of the shores 

 between Martin County and Lake Worth Inlet and between South Lake Worth and 

 Boca Raton Inlets comprising restoration of a protective beach to a general 

 width of 100 feet with a berm elevation of 10 feet above mean low water and 



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