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A two-year study, Lower Gunnison River Basin Wetland Inventory & Evaluation, by Rector, Mustard and Windell, 1978, revealed the observation of one bald eagle and no threatened or endangered plants. A biological assessment was completed and submitted to USFWS in accordance with Section 7(c) of Public Law 95-632. None of the listed species appear to be affected by the proposed action. D. Environmental Consequences Introduction Environmental impacts for each of the alternate plans are displayed in Table Al-4. Primary impacts will occur on those wetlands that have developed since irrigation was first introduced in the valley. Wetland Impacts Wetlands impacted by the Salinity Control Program primarily have developed as a result of introducing irrigated agriculture into the area about 100 years ago. These wetlands may be fed by water seeping from canals, laterals and ditches, fed by water accumulating in natural depressions, fed by subsurface or ground water being forced to the surface by geological conditions, or fed by runoff water following natural or manmade drainage ways back to the river. As irrigation systems and practices are made more efficient the supply of water feeding these areas will diminsh. With diminishing water supply vegetation changes naturally will occur. The Salinity Control Program does not propose to drain wetlands for the purpose of converting them to agricultural or other uses. Because impacts will result from improving the efficiency of existing irrigation systems and practices it is reasoned that the degree of impact for each alterna- tive plan will be inversely proportional to the change in irrigation efficiency. If efficiency remains unchanged, no loss of wetlands is expected; a 10 percent increase in efficiency causes a 10 percent loss in the irrigation induced wet- lands. Impacts will be confined to the respective areas improved by the alterna- tive plans and will be commensurate with the type of improvement made. Localized areas obviously dependent on ditch seepage will be dried up by ditch lining. Larger areas fed by surface, subsurface, or ground water return flows are not expected to vanish completely, however, they may be reduced in size or degree of wetness because less water will be available as return flow. Similar wetlands and riparian wetlands elsewhere in the valley will be unchanged. Secondary impacts will be noticed along earth ditch banks as they are replaced by pipelines, gated pipe or impervious lining. IV-36 The Environmental Subteam of the Interagency Multiple-Objective Planning Team indicated the significant adverse environmental impact resulting from implementa- tion of conservation measures to control salinity would occur on wetland habitat. It is also recognized that salinity control, i.e., water quality improvement, will be a beneficial environmental impact of the salinity control effort.