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Dillon Reservoir: As of July 14, 1999, Dillon Reservoir had filled. On September 1, Denver Water participated in the conference call and reported that the reservoir was spilling (spills continued into October). Denver Water determined they would need to lower the reservoir by about 3.25 feet (by releasing approximately 10,000 acre-feet) before the reservoir froze in mid-December. They volunteered to coordinate this operational need with the other reservoir operators, and were able to release the excess water during October, when it was beneficial to the endangered fish habitat in the 15 Mile Reach. The extra releases from Dillon Reservoir began on October 6 and continued through November 1, totaling 11,478 acre-feet. Williams Fork Reservoir: In September, Denver Water reported that about 2,000 acre- feet of additional releases might be available from Williams Fork if needed to augment flows in the 15 Mile Reach during October or November. During October, Denver Water coordinated the extra releases from Williams Fork with the other reservoir operators. Releases began on October 25, continued through October 31, and totaled 1,825 acre-feet. Granby Reservoir: On September 15, the Northern Colorado Water Conservancy District (Northern) participated in the conference call and reported that Granby releases had been increased from 20 cfs to 400 cfs to prevent spilling. Northern also reported that about 30,000 acre-feet would be available for release from Granby during September and October to augment flows in the 15 Mile Reach. The extra releases from Granby began on September 13, continued through November 1, and totaled 26,914 acre-feet. Willow Creek Reservoir: As for Granby Reservoir, excess water supplies were available from Willow Creek to augment flows in the 15 Mile Reach. Northern released 649 acre-feet from Willow Creek from September 12 through November 2, and 2,733 acre-feet from November 3 through November 22, for a total of 3,382 acre-feet. Irrigation and Power Diversions Five irrigation districts serving approximately 70,000 acres of land in the Grand Valley divert irrigation water from the Colorado River. During periods of peak irrigation demand, up to 2,260 cfs can be diverted via two diversion dams located upstream of the 15-Mile Reach. A portion of the water diverted (about 582 cfs) is used for hydroelectric power generation and hydraulic pumps to lift irrigation water to the Orchard Mesa. This portion of the water returns to the river at the top of the 15-Mile Reach, unless operation of the Orchard Mesa Check structure is required. The Check is normally operated only during dry years, when river flows are so low that GVIC's senior water rights would result in the upstream diversions for GVWUA and OMID being curtailed. Using the Check, GVWUA and OMID can "borrow" water destined for GVIC, use it for hydropower and/or hydraulic pumping, and return it to the river upstream of GVIC's diversion dam (see Figure 2). During 1999, irrigation needs on the GVIC system were at their usual levels until October, with diversions at 640 cfs. As of October 6, irrigation demand had dropped and GVIC had reduced their diversion to 620 cfs. On the Government Highline Canal system, diversions were at 1,520 cfs as of September 1 (100 cfs below the canal capacity of 1,620 cfs). In response to reduced 1999 Late Surnmer/Fall Operations HUP Managing Entities & Water Managers -4-