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<br />:1111 <br /> <br />SUMMARY <br /> <br />WATER QUALITY AND TEMPERATURE <br /> <br />Under the'no-action alternative, water quality in the Gunnison <br />River would not change significantly. Water quality in the <br />Uncompahgre River has historically been poor but may improve as <br />Ridgway Reservoir will settle out sediment and other pollutants. <br /> <br />Under the development alternatives, additional diversion from the <br />Gunnison River would reduce the volume of high quality water <br />available to dilute lesser quality tributary inflows. This <br />reduction in water quality would occur primarily downstream from <br />the North Fork. Temperatures in the Gunnison River would be <br />slightly colder in the winter and warmer in the summer. The con- <br />ditions under which ice forms in the Gunnison River would occur <br />more frequently under the development alternatives. Ice accumu- <br />lation would be most extensive below the North Fork confluence <br />but would also increase above this tributary. Alternative F <br />provides operational changes to decrease diversions and, <br />therefore, increase flows if ice conditions would create <br />environmental problems. The Gunnison River's capacity to remove <br />sediments would be reduced, particularly in the winter. <br />Alternative E would provide for bypassing flushing flows when <br />needed. <br /> <br />Water supplies in the Uncompahgre River in the 12-mile reach <br />between the South Canal and Montrose would receive less high <br />quality water from the Gunnison River during the irrigation <br />season and, thus, less dilution capability would exist. <br />Downstream from Montrose, additional Gunnison River water would <br />be present to dilute sediments and other pollutants. Salt <br />loading to the river would be reduced by the hydropower project <br />through lining the AB Lateral and reducing flow in the South <br />Canal. <br /> <br />SOILS AND VEGETATION <br /> <br />No significant changes in soils or vegetation are projected under <br />the no-action alternative. Under the development alternatives, <br />vegetation and soil disturbance would occur in construction <br />areas. Disturbed areas would be restored and reseeded. A total <br />of approximately 11 acres of wetlands would be lost directly. <br />This acreage would be replaced by creating a wetland area near <br />the powerplant and also by vegetation planting along the <br />Uncompahgre River. Indirect effects are also discussed in the <br />FEIS. <br /> <br />Lower flows in the Gunnison River would allow the establishment <br />of additional riparian and wetland vegetation. However, the <br />scouring of vegetation would occur during high flow periods as <br /> <br />S - 10 <br />