sea level rise and localized land loss “hot spots” occurring along growth faults, access canals, and navigation waterways. Some of the individual causative factors encompass both natural and anthropogenic elements. For example, the extraction of oil and gas near growth faults may speed local subsidence events. Further, public interests often support conflicting management policies. For example, maintenance of the canal system along the lowermost reaches of the Mississippi River benefits the shipping industry, but levees and spoil banks along their margins limit delivery of freshwater, sediments, and nutrients to areas in need of wetland restoration and maintenance. Eliminating levees heightens risk of flooding to businesses and homes located along canals and rivers. Restoring the essential and widespread distribution of sediment and freshwater flow, while maintaining stakeholder acceptance of the adverse impacts of such efforts, will be the overarching challenge to future comprehensive efforts to realize the vision espoused by Coast 2050: Toward a Sustainable Coastal Louisiana (Coast 2050).

SOUNDNESS OF APPROACH AND PERFORMANCE METRICS

In general, the strategies employed in the LCA Study are based on methodologies that have been demonstrated and proven largely through the nearly 15 years of efforts carried out under the Coastal Wetland Planning, Protection, and Restoration Act (CWPPRA). The LCA Study differs from early efforts, such as CWPPRA, in that (1) it recognizes and attempts to address the need for understanding the natural and social systems that are shaping coastal Louisiana today, and (2) it identifies specific actions over the next 5–10 years to address land loss at specific locations in the area. The budget proposed in the LCA Study gives the two components roughly equal weight. This reflects a strong commitment to developing longer-term efforts to restore and protect Louisiana.

Establishing Realistic Expectations

As discussed in some length in Chapters 2 and 3, full restoration of past Louisiana wetland cover and function will not be possible. The natural and anthropogenic processes contributing to net land loss in coastal Louisiana are significant and pervasive, and they have been operating for decades. Achieving no net loss is not a feasible objective because the social, political, and economic impediments are extensive; the sediment supply is limited; and the affected area is large. The LCA Study’s five restoration features would reduce land loss by about 20 percent from 26.7 square kilometers (km2) per yr (10.3 square miles [mi2] per yr) to 22.3 km2 per yr (8.6 mi2 per yr). More extensive wetland protection than proposed in the



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