(1) controlled introduction of Mis- 

 sissippi River water into adjacent 

 estuarine marshes and bays for salin- 

 ity control and nutrient input; and 



(2) creation of subdeltas along the 

 lower Mississippi River through con- 

 trolled freshwater diversion into 

 adjacent shallow bays. 



A multi-use management plan for 

 south-central Louisiana was subse- 

 quently developed (Gagliano et al. 

 1973a). This plan recommended cer- 

 tain developmental controls, manage- 

 ment and maintenance of barrier 

 islands, erosion control, and surface 

 water management including supple- 

 mental freshwater introduction, 

 management of existing runoff sur- 

 pluses and controlled subdelta build- 

 ing with diverted Mississippi River 

 water and sediments. 



Despite the virtually universal 

 recognition of the seriousness of the 

 wetland deterioration problem in the 

 LCR and the existence of plans to 

 address that problem, no major feder- 

 ally financed measures have been 

 implemented. However, two ongoing 

 federal water resource studies being 

 conducted under the leadership of the 

 U.S. Army Corps of Engineers offer 

 considerable promise for large-scale 

 supplemental freshwater introduction 

 into the subdelta marshes of the LCR. 

 These include the Louisiana Coastal 

 Area Study and Mississippi and 

 Louisiana Estuarine Areas Study. With 

 regard to the latter study, prelimi- 

 nary estimates by the U.S. Fish and 

 Wildlife Service indicate that be- 

 tween $4.4 and $5.2 million in 

 annual benefits to fish and wildlife 

 can be realized with a single large- 

 scale diversion into the Lake Pont- 

 chartrain-Lake Borgne area of south- 

 east Louisiana (Fruge and Ruelle 

 1980). 



In 1979, the Louisiana Legis- 

 lature enacted legislation directing 

 the Secretary of the Louisiana De- 

 partment of Transportation and 

 Development to prepare a freshwater 

 diversion plan for Louisiana. That 

 plan is expected to complement any 

 freshwater introduction measures 

 implemented by Federal agencies. 



CONCLUSIONS AND RECOMMENDATIONS 



It is clear that the important 

 fish and wildlife resources of the 

 LCR are threatened by rapid, contin- 

 ued degradation of its wetland habi- 

 tat through land loss and saltwater 

 intrusion. This problem is widely 

 recognized by natural resource man- 

 agers, scientists, and the public at 

 large, and positive measures have 

 been proposed to address it. How- 

 ever, definitive action must be 

 taken to implement these measures 

 at the earliest possible date. Be- 

 cause federally constructed flood 

 control and navigation works have 

 played a major role in the deteriora- 

 tion of Louisiana's coastal wetlands, 

 it would seem that mitigation of 

 these adverse impacts should be 

 accomplished primarily through the 

 public works programs of the Federal 

 Government. 



LITERATURE CITED 



Adams, R. D.; Barrett, B. B.; Black- 

 mon , J . H . ; Gane , B . W . ■ 

 Mclntire, W. G. Barataria Basin: 

 geologic processes and frame- 

 work. Baton Rouge, LA: Louis- 

 iana State Univ. , Center for 

 Wetland Resources,- Sea Grant 

 publication no. LSU-T-76-006 

 1976; 117p. 



394 



