Drawing Louisiana's New Map Addressing Land Loss in Coastal Louisiana (2006) / Chapter Skim
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5 The LCA Study Planning Approach, Modeling, and Project Selection Process
5 The LCA Study Planning Approach, Modeling, and Project Selection Process
Pages 87-114
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From page 87... ...
to counter serious land loss rates · Examines past and proposed efforts to engage stakehold ers · Discusses models used in the project selection process and identifies their strengths and weaknesses · Examines the overall project selection process In an area as vast and complex as the Louisiana coastal region, planning for restoration is a challenge. The fields of ecology, wetland science, hydrology, geology, oceanography, computer modeling, engineering, sociology, economics, political science, land-use planning, hazard mitigation, and law can make a contribution in defining the problem and providing possible solutions; therefore, these fields must be considered in the design process.
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From page 88... ...
Most of coastal Louisiana is privately owned or at least subject to some claim of private ownership (Davis, 2002)
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From page 89... ...
Environmental organizations will be involved as habitats are changed and restored. There will be tension between those that have adjusted to the land loss and salinity change by changing their occupations and lifestyle and those that will benefit from land restoration and the increasing freshness of the waterways.
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From page 90... ...
Army Corps of Engineers, 2004a)
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From page 91... ...
ROLE OF MODELS IN THE PLANNING AND ADAPTIVE MANAGEMENT OF THE LCA STUDY PLANNING PROCESS Models have been used in attempts to understand the physical processes within the project area, for the development of the Louisiana Coastal Area, LA -- Ecosystem Restoration: Comprehensive Coastwide Ecosystem Restoration Study (draft LCA Comprehensive Study) , and for project selection and prioritization of actions within the LCA Study, and they are expected to be part of the future Adaptive Environmental Assessment and Management (AEAM)
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From page 92... ...
These models can be used to simulate the endpoints of engineering alternatives" (U.S. Army Corps of Engineers, 2003a)
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From page 93... ...
Army Corps of Engineers)
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From page 94... ...
Land building module Sediment Land water ratio Organic Elevation matter Water Hydro- level Habitat Habitat use dynamic switching Habitat module module module use Salinity Nutrient Nutrient sinks availability Rate of inflow Water quality module FIGURE 5.2 Linkage of different modules used in desktop and simulation models (U.S. Army Corps of Engineers, 2004a; used with permission from the U.S.
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From page 95... ...
95 of Corps ater Habitat switching W quality its/ Army 4 aluation gion Plain Benef ev (U.S. Chenier endpoints Re Hydrodynamic use Land uildingb Habitat Study LCA the ater in 3 Habitat Habitat switching switching W quality its/ gione errebonne used R Acadiana endpoints aluation Hydrodynamic Benef ev Bays/T Land uildingb use Land uildingb Habitat evaluation Engineers)
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From page 96... ...
developed by the U.S. Army Corps of Engineers (USACE)
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From page 97... ...
Figure 5.4 illustrates that large gaps within the Louisiana coastal area are not covered by deterministic models. Because of the differing objectives of the models selected, there is no consistency in the selection of bathymetry (where available)
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From page 98... ...
98 Use Habitat Input Input Input Input Switching Habitat Input Input Input Quality Water Input Input Input Input Input Input Input Input Modules Change a Land Input Input Input Input Input Input Input Input Input Input Among a Interactions Module Hydrodynamics Input Input Input Input Input Input Input Input Input Output Output Output Output Output and Variables rates soils factor direction time change load deltaic Module and level of factor area 5.1 land retention flows speed water salinity temperature temperature sediment land density elevation nitrogen level residence temperature TABLE Variable Wind Initial Initial Initial River Historical River Sediment Bulk Initial Bathymetry Land Diversion River Nourishment Salinity Water Water Water
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From page 99... ...
99 the 4, region Input Input Output Output Output Output Output Output Output Output Output Output Output Output .In basin receiving the Input Output of salinity initial the on Input Output Output scenario. based is and no-action the Output to freshwater to relative refers salinity factor in 2003a.
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From page 100... ...
Uncertainties and gaps in knowledge have been systematically identified (U.S. Army Corps of Engineers, 2003a)
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From page 101... ...
PROJECT SELECTION AND THE LINK WITH MODELING The draft LCA Comprehensive Study and the LCA Study both outline in detail the methodology for project selection (U.S. Army Corps of Engineers, 2004a)
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From page 102... ...
Protects vital socioeconomic resources Three Alternative Plans Plan N: Alternative Plan B: Alternative Plan: Meets all four critical Shortcomings in Shortcomings in and needsplan that best restoring critical addressing Mississippi meets the objectives geomorphic structure River reintroductions Array features and opportunities on how fast can start Apply $1.9 million Get five projects FIGURE 5.5 Overview of the project selection process (U.S. Army Corps of Engineers, 2004a; used with permission from the U.S.
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From page 103... ...
The final features were ordered based on the time required for implementation, and those consistent with the available funding became the top five projects. These steps are reviewed carefully in this section because this process forms the basis for project selection for the LCA Study and is assumed to be the prototype for future plans.
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From page 104... ...
For example, an index of the proximity of a project area to a major urban settlement, an index of navigation protection, or the reduction in hurricane risk or river flooding would be measures that could be incorporated for cost-effectiveness analysis. Inclusion of these types of indices would probably skew project selection toward projects having more beneficial socioeconomic impacts, compared to using the initial ecological selection criteria with a "socioeconomic critical need" criterion applied only in the final steps of the analysis.
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From page 105... ...
Army Corps of Engineers, 2003a)
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From page 106... ...
. For example, the Mississippi River Gulf Outlet (MRGO)
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From page 107... ...
3. Barataria Basin barrier shoreline restoration ($247.2 million,7 28.6 percent of the total cost)
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From page 108... ...
However, since the physical and ecological relationships between projects in a framework are not clear and frameworks optimized for cost include many projects that are not chosen for implementation, the actual role of socioeconomic factors in project selection is not clear. Furthermore, although the cost-effectiveness analysis was carried out on frameworks, the selection decision was made for individual features.
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From page 109... ...
Since ecological and economic success might be greater or more certain with larger projects, why was the focus not on a few larger projects? Would a big initiative to save and restore barrier islands coupled with several large strategically located diversions not be more effective and informative than many "small" projects?
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From page 110... ...
It is also possible to design projects so that interactions among altered natural processes may have synergistic, beneficial effects. As discussed in greater detail in Chapter 6, the five restoration features selected and proposed in the LCA Study do not appear to reflect an attempt to optimize project selection to maximize positive synergistic effects.
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From page 111... ...
This scoring would provide a rational economic input to project selection. The draft LCA Comprehensive Study and the LCA Study make repeated references to the importance and economic value of the fisheries dependent on Louisiana wetlands.
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From page 112... ...
This effort should be structured to attract synergistic collaborations among modelers worldwide and to enhance the current extensive regional expertise in federal and state agencies and academia. The project selection process primarily used ecological benefits early on in project formulation and then used least-cost alternatives for aggregates of projects (i.e., frameworks)
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From page 113... ...
While the efforts preceding the LCA Study achieved a laudable degree of unanimity among stakeholders on the conceptual restoration plan, this unanimity will be tested by the difficult decisions associated with implementation of the larger-scale projects necessary to achieve greater sediment, water, and nutrient delivery more effectively over a larger area. The project selection procedure requires more explicit accounting of the synergistic effects of various projects and improved transparency of project selection to sustain stakeholder support.
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