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<br />t <br /> <br />Table 3. Summary of wetland types In the project area based on their condttlon. <br /> <br />t <br /> <br />Wetland Type and Condition <br /> <br />Acres <br /> <br />Wetlands In POOl' Condition <br />Wet meadow <br /> <br />682 <br /> <br />. <br /> <br />Wetl4nds In Good Condition <br />Wet meadow <br />Willow riparian <br />Pond:; <br />Cottonwoodlwillow riparian <br />St1eam~ <br /> <br />,<3 <br />3Il <br />6 <br />J <br />16 <br /> <br />Total WeUands <br /> <br />692 <br /> <br />I <br /> <br />682 acres have been affected by humans (fable 3). Of the 210 acres of high-value wetlands, <br />approximately 143 are wet meadow; 38 acres are willow riparian; 17 acres are fast moving stream; 1 <br />acre is slow moving stream; 8 acres are standing water; and 3 acres are cottonwoods. <br /> <br />I <br /> <br />The functional va/ues of wetland habitat includes groundwater discharge and recharge, flood storage <br />and desynchronization, shoreline anchoring and dissipation of erosive forces, sediment trapping, <br />nutrient retention and removal, food chain support, wildlife and fish habitat, and active and passive <br />recreation and heritage value (Adamus and Stockwell 1983). <br /> <br />Because the wetlands that will be inundated in the project area are in generally poor condition <br />(USDNUSDI 1988), the overall functional value of these wetlands is low. Land management activities <br />have resulted in compacted solis, overgrazing, vegetation cropping, and subsequent lowering of the <br />natural water table due to widening and incisement of Muddy Creek below its floodplain. Recent <br />analysis completed by BIONVEST and RCI (Grah 1989) provides evidence that Muddy Creek has <br />abandoned the valley flat area as an active floodplain due to channel widening and incisement. In <br />general, point bars and an incipient floodplain are being newly constructed by the creek at a level two <br />to three feet below the abandoned floodplain level. <br /> <br />In addition, based on information presented by Adamus and Stockwell (1983), the reservoir will replace <br />or improve most of the lOW functional values of the inundated wetlands except wildlife value. These <br />functional values include the following: <br /> <br />Groundwater DlscharQe: This functional value involves the role wetlands play in regulating stream <br />flows through groundwater discharge. At present, it appears that the Muddy Creek wetlands are not <br />retaining as much 01 the sulface water runoff as would a wetland in better condition. Hence, a <br />reduced quantity 01 surlace water infiltrates or percolates into the groundwater. Therefore, groundwater <br />discharge from the Muddy Creek wetlands to the creek is reduced from levels associated with a <br />wetland in good condition. The reservoir will tully replace or exceed the value of this low flow <br />augmentation. First, the reselVoir will increase the hydraulic head 01 groundwater above and below the <br />reservoir. Such an increase in hydraulic head could effectively raise the water table below the dam <br />thereby increasing basetJow augmentation as well as consumptive use by the hydrophytes. Second, <br />reservoir management will involve releasing greater flows than that of the current situation during low- <br />now periOds. Therefore, the presence and operation of the reservoir will replace or exceed the current <br />groundwater discharge value of the inundated wetlands. <br /> <br />5 <br />