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<br />..,:~..j~:\rr.~' <br /> <br />,rl 1>, . ~ ~ ~ffected Environrnent & Consequences <br />{,U10j <br /> <br />3-24 <br /> <br />the Aspinall Unit reservoirs. Specific conductance is low, indicating excellent water <br />quality at the East Portal. The Gunnison River from Crystal Dam to a point 1 mile below <br />Smith Fork confluence is classified as a High Quality, Class 2 waterbody. The Gunnison <br />River from a point 1 mile downstream of the confluence with the Smith Fork to <br />immediately above the confluence with the Uncompahgre River is classified as a <br />Recreation Class 2 Aquatic Life - Class 1 Cold Water Supply Agriculture. Recreation <br />Class 2 signifies stream segments where primary contact recreation (swimming) does not <br />exist and cannot reasonably be expected to exist in the future (boating is acceptable under <br />this classification). Water bodies classified as Aquatic Life Class 1 Cold Water support <br />cold water animal species, such as trout. <br /> <br />Water quality within the Gunnison River declines below the confluence with the North <br />Fork, primarily because of irrigation return flows and increased sediment. The decline in <br />water quality below the North Fork confluence is reflected by the increased specific <br />conductance at Delta. Also, specific conductance and water temperature varies seasonally <br />at the Delta gauge more dramatically than at the East Portal gauge. <br /> <br />3.6.1.2 Uncompahgre River <br /> <br />Water quality of the Uncompahgre River is poor compared to the Gunnison River and is <br />apparently the result of excessive amounts of dissolved solids from irrigation return <br />flows. The Uncompahgre River from its source to a point immediately above the <br />confluence with Red Mountain Creek is classified as a Recreational Class 2 Aquatic Life <br />- Class I Cold Water Supply Agriculture. From above the confluence with Red Mountain <br />Creek to US Highway 550 south of Montrose, the river is classified as a Recreational <br />Class 2 Aquatic Life - Class 1 Cold Agriculture, From Highway 550 south of Montrose <br />to the confluence with the Gunnison River (most of the Study Area), it is classified as <br />Recreational Class 2 Aquatic Life - Class 2 Warm Agriculture. The Aquatic Life <br />designation becomes Class 2 warm water here, indicating no significant cold water sport <br />fishing between this point and the Uncompahgre River's confluence with the Gunnison <br />Ri ver at Delta. <br /> <br />3.6.2 Impacts of Alternatives <br /> <br />3.6.2.1 Alternative A (No Action) <br /> <br />Under the No Action alternative, water quality in the Gunnison River would not <br />significantly change. Water quality of the Uncompahgre River has historically been poor <br />but may improve, as Ridgway Reservoir will settle out sediment and other pollutants. <br /> <br />3.6.2.2 Gunnison River <br /> <br />Under the development alternatives, additional diversion from the Gunnison River would <br />reduce the volume of high quality water in the Gunnison available to dilute lesser quality <br />tributary inflows between the Tunnel and Delta (see Table 3-9). This reduction in water <br /> <br />AS Lateral Hydropower Project <br /> <br />JUly 2000 <br /> <br /> <br />) <br />