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<br />Reevaluation of Habitat Impacts <br /> <br />Coordination with the FWS and CDOW was resumed with further study of the 1984 Plan. A <br />team was formed and reviewed the 1979 wetland inventory and evaluation (Rector). <br />Reclamation updated it with an inventory and evaluation of seepage-dependent wetlands along <br />canals and laterals east of the Uncompahgre River (1991). The inventory was designed to <br />allow separate identification of wetlands and impacts by canal and lateral increments. Instead <br />of using species-specific habitat evaluation procedures, the study detennined "Wetland Value <br />Units" (WVU). Site evaluations of randomly selected sample sites rated hydrologic and <br />biologic attributes of each wetland site. Values for wildlife functions rated much higher than <br />hydrologic functions. The result of the rating was a "wetland value index" (WVI) for each <br />acre of the site that range from 0.1 (low value) and l.0 (high value). A value of 1.0 shows <br />that the wetland rates as high as possible in all wetland functions. This index was quantified <br />into units by multiplying it by the acreage of inventoried wetlands: <br /> <br />WVI x Acres of Wetlands = Wetland Value Units <br /> <br />The inventory mapped a total of 727 acres of seepage-dependent wetlands along both the <br />canals and 13terals. Of these, 416 acres were along the laterals and involved 363 sites. The <br />weighted average WVI for all types of wetlands dependent on seepage along the laterals <br />averaged 0.39. Results showed about 165 wetland value units (or 165 acres of fully-valued <br />wetlands), would be lost. <br /> <br />Inventoried wetland sites ranged in size from 0.1 to 22.3 acres and averaged 1.4 acres. <br />"Emergent" wetlands comprised 6%.4 percent of the total, averaged 0.6 acres in size, and had <br />an average wetland value index of 0.42. They typically consisted of saltgrass flats and <br />sedge/wet grass meadows (narrow-leafed species). Some broad-leafed emergents occurred <br />that consisted of cattails, reeds and bulrush. Thickets dominated by young willows were the <br />most common "shrub-scrub" wetland. These thickets usually extended only short distances <br />from canal or lateral banks. Shrub-scrub wetlands comprised 24.5 percent, with an average <br />size of 1.6 acres and average WVI of 0.32. "Forested" wetlands made up only 7.1 percent, <br />averaged 1.1 acres in size, but had the highest WVI averaging 0.44. They typically <br />consisted of small stands of cottonwoods with minimal understory vegetation. <br /> <br />Reclamation's 1991 inventory also 750 counted mature cottonwood trees that would be lost <br />by elimination of seepage along the laterals. These scattered trees are important from both <br />an aesthetic and wildlife habitat standpoint. <br /> <br />Reclamation's inventory did not identify "prism" habitat that would be destroyed by piping <br />the laterals. This habitat provides open water resources in the project area. Reclamation <br />used design data (length and capacity of the laterals) to quantify prism habitat losses. Results <br />estimate about 122 acres (see Attachment B) would be lost. Habitat values along the ditches <br />are reduced by annual maintenance activities to eliminate vegetation along the banks. <br />Typical activities include spring burning, seasonal herbicide spraying, and periodic ditch <br /> <br />18 <br />