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River Regulation " RelNHll from Bartlett o.m. The natural virgin runoff reaching the streams of the Colorado RIver drainage system above Glen Canyon Dam during water year 1982 was .stlmatad at aboul16.3 million acra-feet. Of ~h'ls amount, about 3.9 million 9-ere-feet were consumptively used within the Upper Colorado River Basin Statas. Adjustments In storage In main stem reservoirs resulted In an Inflow to Lake Powell of 11.1 million acre-feet. The release trom Glen Canyon Dam, based on measurements at the gagIng station at Lees Ferry, Arizona, was 6,295,000 acre-feet, For the1-year and 10-year periodS ending September 30,1962, 6,312,000 acre-feet and 69,679,000 acre-feet, respectively, passed the Compact point at Lee Ferry, 22 The projected release from Lake Powell, based on lower quartile runoff conditions or less, Is 8,230,000 acre-feet. The projected release for an upper quartile runoff condition 1.12,000,000 acre-feet. When added to the flow of the Paris River, this would result In an Upper Basin delivery ranging from 86,8 to 90,5 million .cre-feet for thel0-ye.r period ending September 30, 1983. Dally releases are made from the storage reservoirs In the Lower Basin to meet the Incoming orders of the water agencies. Normally. all water passes through the powerplant units. The dallY releases a.rB regulated on an hourlv basis to meet as nearlv -as possible the DowAr I,.,,,,ria I'll thA AIAetrlG power customers. Minimum dally flow objectives are provided In the river to maintain fishery habitat. ~ .;,.i~....~ Gila Rfver fl<<4lng. Adjustments to the normal releases arB made when conditions permit to provide more satisfactory conditions for water-oriented recreation activities, to provide transport for rlverborne sediment to desllUng facilIties, and to assist in controlling water quallty. Releases from Lake Powell were at least 1,000 cts during the winter months and were increased to at least 3,000 cfs during the summer months. Minimum daytime releases during the summer months averaged 8,000 cts. River regulation below Hoover Dam resulted In a total delivery to Mexico of approximately 330,000 acre-feet In excess of the treaty Quantity (1,500,000 ac(e-feetl during water year 1982, Of that amount, 145,000 acre-Ieet of drainage waters were bypassed for salinity control pursuant to proviSions of Minute No. 242 of the Commission.