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Salinities at each of the three lower mainstem stations for which numeric criteria have been established have decreased since 1972. 2. FORECAST OF STREAM FLOW The April 1, 1991 forecast of inflow to Lake Powell by the National Weather Service, Department of eommerce, for April- July was estimated to be 4,600,000 acre-feetl. The unregulated inflow to Lake Powell for the period April- July 1991 amounted to 5,286,000 acre-feet2, which was about 70 percent of the 29-year (1963-1991) average flow. During the April-July 1991 period, changes in storage in eolorado River Storage Project reservoirs including Lake Powell resulted in an overall increase of 1,330,000 acre-feet, with 248,000 acre-feet of evapo- ration and a 78,000 acre-foot decrease in bank storage3. Actual regulated inflow to Lake Powell for the period April- July 1991 was 4,183,000 acre-feet. For the period October 1, 1990 through September 30, 1991, the change in reservoir storage, excluding bank storage and evaporation, at selected reservoirs above Lake Powell was: Fontenelle decreased 45,700 acre-feet; Flaming Gorge increased 308,700 acre-feet; Taylor Park in- creased 5,400 acre-feet; Blue Mesa increased 81,900 acre-feet; Morrow Point decreased 5,400 acre-feet; erystal decreased 600 acre-feet; and Navajo increased 225,400 acre-feet. The virgin flow4 of the eolorado River at Lee FerryS forthe 1991 water year amounted to 11,600,000 acre-feet€'. lIncluding water to be stored upstream in other Colorado River Storage Project Reservoirs. 2Adjusted for upstream regulation and depletions. 3Includes Flaming Gorge Reservoir on the Green River. 4Virgin flow is the estimated flow of the stream if it were in its natural state and unaffected by the activities of man. 5Lee Ferry, Arizona is the division point between the upper and lower basins of the Colorado River as defined in the Colorado River Compact. It is located about one mile downstream from the mouth of the Paria River and about 16 miles downstream from Glen Canyon Dam. 6Based on provisional records subject to revision. 9