The Shoshone hydroelectric power plant in Glenwood Canyon should be back online by spring 2008, according to an announcement Thursday from Xcel Energy, which owns the plant.The 14-megawatt power plant has been down since June 20.The plant being offline has caused major ripples up and down the Colorado River for the owners of water rights on both the Front Range and the Western Slope.The Shoshone plant controls 1,250 cubic feet of water rights, which cannot be exercised while the plant is down. Those water rights have served as a reliable level of water in the river for both whitewater rafters and endangered fish species near Grand Junction.An agreement by the major water interests on the river brokered by the Colorado River District is ensuring that the river through Glenwood Canyon is flowing at least 1,200 cfs through Labor Day, which is enough water for commercial rafting companies to offer a good experience and enough water to keep the fish healthy near Grand Junction.According to Xcel, repairs to the Shoshone plant are estimated to cost $12 million and will include repairing and upgrading both penstocks, the large metal tubes used to bring water into the plant's turbines from the water delivery system above the plant. Water from the river is diverted upstream of the plant and sent along the cliff face until it reaches the location of the plant. Then the water is sent rushing downhill to the plant, through its turbines, and back into the river. Repair crews will begin construction in September and are slated to finish by the beginning of spring 2008."I would call this relatively good news," said Eric Kuhn, general manager of the river district. "We were all expecting the worst of another two years."Kuhn said it would be a good thing if the plant is back online before late June of next year and the start of another rafting season. He wasn't overly concerned about having enough water in the river through the winter, as diversions to the Front Range at that time are relatively low."A lot of that depends on how full reservoirs are going into the winter and the winter snowpack," he said, adding that if the winter snowpack looks healthy, reservoir operators will let more water out during the winter. In terms of the fish, Kuhn said it will be important to keep enough water in the river and make sure that the river levels don't fluctuate and leave fish eggs high and dry or exposed to freezing temperatures.The recommended stream-flow levels in the upper Colorado River range from 90 to 150 cfs. Below those levels the aquatic habitat in the river can be compromised. The 98-year-old hydroelectric plant was damaged on June 20, when one of two penstocks ruptured and caused water and debris to flood the generating station and switching yard. Approximately eight feet of water and many tons of rock and soil rushed into the station, according to Xcel officials, who said the rupture was caused by pipe corrosion. "Although the damage was considerable, and the clean-up tough, we're committed to returning it to full operation," said Lou Matis, vice president of operations of Xcel. "We appreciate the patience of other Colorado River water users, and the cooperation of the Colorado Department of Transportation and emergency responders during the event."Frequent rains this summer has helped the situation in the Colorado River and have lessened the level of cooperation needed by water interests to keep the river at the 1,200 cfs level.On Thursday, the Colorado River was flowing at 1,660 and has fluctuated mainly between 1,400 and 1,600 cfs river throughout the summer.bgs@aspendailynews.com