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<br />Glen Canvon Dam - Lake Powell <br /> <br />Experimental releases from Glen Canyon Dam began on January 1,2003. Daily high fluctuating <br />releases from Glen Canyon Dam will be implemented from January through March 2003 to reduce <br />spawning and recruitment of non-native fish. Releases will range between a high of 20,000 cubic <br />feet per second (cfs) to a low of 5,000 cfs each day. The 20,000 cfs releases will be maintained for <br />approximately 9 hours each day (from about 11:00 a.m. to about 8:00 p.m.), while the 5,000 cfs <br />releases will be maintained for approximately 8 hours each day (from about 1:00 a.m. To about 9:00 <br />a.m.). The remainder of the hours will be transition releases where releases are between the daily <br />high and the daily low. This pattern will be maintained for 7 days a week during the January through <br /> <br />March time period. It should be noted that due to real-time power generation considerations and <br />regulation to stabilize the power system, actual releases may deviate somewhat from this pattern. <br /> <br />The January through March high fluctuating releases are intended to benefit the endangered <br />humpback chub. Scientists have recognized that the humpback chub population has been in general <br />decline since highly fluctuating flows were curtailed in November of 1991. Those flows helped <br /> <br />keep the non-native fish, especially the rainbow and brown trout, in check. The trout are thought to <br />prey upon and compete with native fish such as the endangered' humpback chub. <br /> <br />The high fluctuating releases will continue through March 2003. Monthly release volumes from <br />Glen Canyon Dam in January, February, and March 2003 will be 788,000, 712,000, and 788,000 <br />acre-feet, respectively, which averages out to 12,800 cfs per day. <br /> <br />The experimental releases from Glen Canyon Dam received environmental clearances in December <br />2002. The flows were analyzed in an environmental assessment in accordance with the National <br />Environmental Policy Act. The experimental flows are the result of ongoing studies by scientists <br />from the United States Geological Survey and were recommended by the Glen Canyon Dam <br />Adaptive Management Work Group, a federal advisory committee. The experimental releases <br />address the decline of two key resources in the Grand Canyon: sediment and population viability of <br />endangered humpback chub. The environmental assessment can be found at the following site: . <br />http://www.uc.usbr.gov/envdocslealgc/gc_release.html <br /> <br />Drought conditions persist in the Colorado River Basin. The basin received some drought relief <br />during the months of September and October, with basinwide precipitation in those months being <br />185 and 110 percent of average, respectively. Basinwide precipitation in November was 95 <br /> <br />percent of average but only about 65 percent of average in December. Snowpack in the Colorado <br />River Basin is currently 83 percent of average (as of January 3, 2(03). The January inflow forecast <br />issued by the National Weather Service is calling for 5.7 million acre-feet of unregulated runoff into <br />Lake Powell during the 2003 April through July time period. This is 72 percent of average. <br /> <br /> <br />Inflow to Lake Powell continues to be significantly below average. Unregulated inflow into Lake <br />Powell in October, November, and December 2002 was 56, 69, and 57 percent of average, <br />