BUILDING A WETLAND 



The procedures and techniques employed by the CE in the development of a 

 wetland are described in the following paragraphs. A more detailed account of the 

 items discussed can be found in the referenced reports. This discussion pertains to the 

 construction of a wetland where none previously existed. Most such situations 

 involve the use of fill material. 



A wetland may be built for a number of reasons, including mitigation of wetland 

 destruction, prevention of erosion, shoreline or bank stabilization, and reclamation 

 of an existing disposal or construction site to increase its wildlife value. A wetland 

 may be used alone as a singular habitat or built in conjunction with aquatic, upland, 

 or island habitat. It may also be used to introduce a new type of habitat into an area, 

 where previously little or none of that type had occurred. 



Once an initial decision has been made to build a wetland, there are three major 

 phases necessary to the successful establishment: planning, engineering, and plant 

 propagation.!^ 



PLANNING 



Many types of wetlands can be developed, including intertidal salt and fresh 

 marsh, semipermanently flooded fresh marsh, riverine or lake habitat, and shrubby 

 and forested wetlands. Techniques discussed here are sufficiently general to apply to 

 most situations, but the reader is urged to consider each site as unique and worthy of 

 the site-specific considerations set forth in references 16, 17, and 20. 



Site Selection 



Site selection should be based on a number of factors including the availability, 

 accessability, size, physical and engineering features, environmental and social 

 acceptability, and tidal, current, wind, and wave considerations. 



Site Characterization 



Once a site has been tentatively selected, the need for more precise physical and 

 biological information becomes necessary. Key environmental considerations often 

 consist of public attitudes, aesthetics, loss of open-water habitat, changes in the 

 energy and hydrologic regime, and pollutant mobilization. Substrate characteristics 

 at the site and characteristics of the material to be placed on the site should also be 

 determined. Site configuration, topography, elevation, and size should be identified, 

 so that adjustments can be planned and made if necessary. Existing wildlife and plant 

 species on and adjacent to the site should be noted, as these are probably the species 

 that will colonize the newly built wetland. Water regimes should be understood so 

 that necessary protection can be provided. Measurements of substrate stability 

 should be made, and the availability of materials for any necessary dikes or retaining 

 structures should be determined. 



Special Considerations 



The legalities of creating a wetland are often complicated and vary from state to 

 state. There are a number of Federal and state laws that come into play and involve 

 zoning, endangered species, water quality, transport of plant material, ownership of 

 property, disruption of existing habitat, and other regulations and considerations. 

 Other common concerns include the needs and desires of local residents, construc- 

 tion agency authorization, and project costs. 



ENGINEERING 



The project engineer must have accurate information on the volume and 

 engineering characteristics of the fill material, the foundation characteristics of the 

 site, and the local hydrologic forces. The project design should consider a wide range 



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