Suboeftal Sandy Ekirnen 



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a 10 20 30 40 50 



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Figure 1. Location of Louisiana's barrier islands. 



saltwater intrusion, hurricane stornn surge, and deep water wave attacks . In this way, 

 Louisiana's barrier islands help to support a finfish and shellfish industry which accounts 

 for over 25% of the total U. S. commercial catch each year. (2) Barrier islands provide 

 habitat for wildlife and shelter for endangered or threatened species. (3) Barrier islands 

 provide protection for mainland areas, including oil and gas facilities which generate 

 considerable tax revenues for Louisiana. (4) Since the three-mile boundary for 

 Louisiana's territorial waters is measured from the barrier islands, the State is concerned 

 with the problem of continued landward migration of the barrier islands as this migration 

 could result in a reevaluation of the State's three-mile boundary and a net loss of oil and 

 gas leases to the Federal Government. (5) Barrier islands offer recreational 

 opportunities and aesthetic qualities unique to this system. 



The use of hard structures (groins, jetties, seawalls) to control or reduce barrier 

 island erosion in Louisiana has met with limited success (Penland and Boyd 1981). In the 

 case of groins and jetties, accretion may result at the updrift side of the structure, e.g., 

 the east end of Grand Isle, but accelerated erosion often occurs at a downdrift location, 

 e.g., the Grand Terre islands. The inherent problems with structures like groins and 

 seawalls are now being recognized (Leatherman 1980). Seawalls, for example, only 

 protect what is landward; accelerated beach erosion often occurs seaward of these 

 structures (Silvester 1977). In addition, these structures destroy the aesthetic qualities 

 that attract so many people to these ecosystems. Sand dune building and stabilization 

 offer a sound alternative to the hard structure approach to erosion abatement. 



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