SPECIFIC RECOMMENDATIONS FOR 

 MDPR MANAGEMENT 



A number of workers have suggested 

 specific actions for dealing with vari- 

 ous environmental problems in the MDPR. 

 Many of these recommendations represent 

 the mainstream approach to environmental 

 management: they are intended to be 

 incorporated in regulations, and they 

 are based on implicit subjective analy- 

 sis of indirect impacts and weightings 

 of environmental and economic costs and 

 benefits . 



A different approach, and one po- 

 tential use of the data collected in the 

 technical report, is a more explicit, 

 objective analysis of indirect environ- 

 mental impacts and the relative weight- 

 ing of these impacts using input-output 

 models. Since these data have yet to be 

 fully analyzed, the indirect impact 

 magnitudes and ecological prices are not 

 yet available. In this section, we 

 review specific recommendations that 

 have been made and suggest how the 

 results of the analysis of the data 

 collected in the technical report might 

 be incorporated into the management 

 process, when the results become avail- 

 able. 



WETLAND LOSS 



Two possible ways of managing the 

 problem of wetland loss are: (1) to 

 minimize the additional loss of wetland 

 or (2) to build new wetland to offset 

 losses. The most important source of 

 sediments to build new land is the 

 Mississippi River. Two approaches have 

 been suggested for land building and are 

 listed in Table 25: (1) controlled 

 diversions on the lower Mississippi 

 River channel, and (2) optimizing land 

 building in the Atchafalaya Bay region. 



Because canals appear to be a major 

 factor in coastal wetland loss, prohi- 

 bition or strict regulation of new 

 canals and backfilling of old canals 

 would have a remedial effect on con- 

 tinuing wetland loss. A number of 

 recommendations have been suggested to 



minimize the impact of canal construc- 

 tion (Table 26). 



Since many canals are dredged for 

 access to drill sites, several alterna- 

 tives have been suggested. These in- 

 clude directional drilling that would 

 reduce the number of canals necessary, 

 and hydroair cushion vehicles that would 

 eliminate the necessity for canals. 

 Information also exists suggesting that 

 the air cushion drilling system might be 

 economically competitive with tradi- 

 tional drilling rigs on barges (Table 

 27). 



Barrier island stabilization has 

 also been suggested to retard land loss 

 of both islands and the wetlands they 

 protect from storm wave activity. 

 Structural and biological approaches can 

 be considered. The structural approach 

 usually involves construction of groins 

 and rip-rap, which may stabilize one 

 area at the expense of another. Penland 

 and Boyd (1981) pointed out examples of 

 the limited success of structural 

 methods, while Leatherman (1980) and 

 Silvester (1977) discussed the inherent 

 problems associated with seawalls and 

 groins. Beach nourishment (pumping sand 

 onto the beach from offshore) is another 

 technique that has been used, especially 

 along the South Atlantic coast. The 

 biological approach generally involves 

 planting grass to stabilize dunes. This 

 method appears to be successful at least 

 in the short term (Mendelssohn 1982). 



Barrier islands are transient fea- 

 tures. A limited coastal sand supply 

 has produced in Louisiana the most 

 serious barrier island erosion problem 

 in the United States, causing island 

 retreat (landward migration) rates of as 

 high as 50 m/yr, and land loss rates of 

 65 ha (160 acres) per year (Mendelssohn 

 1982). 



Rational decisions concerning the 

 various recommendations to control land 

 loss require the comparison of economic 

 and ecological costs and benefits. If 

 the total (social) cost of removing a 

 particular area of natural habitat from 

 production were known, the effectiveness 

 of the various mitigation techniques 



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