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<br />Table 1
<br />MEASURED FLOW IN COlORADO RIVER
<br />BASIN FOR WATER YEAR 1968-69
<br />(Thousands of Acre-Feet)
<br />
<br />St/1tion
<br />
<br />Upper Basin Measured Flow
<br />Green R. at Green River, Utah.... ................ .................... 4,864
<br />Colorado R. near Cisco, Utah .................................................... 4,792
<br />San Juan R. near Bluff, Utah .................................................. 1,649
<br />
<br />Colorado R. at Lee Ferry............................................................ 8,863
<br />
<br />Lower Basin-C%rado River
<br />Near Grand Canyon ....................................................................9,284
<br />Below Hoover Dam...................................................................... 7,986
<br />Below Davis Dam ........................................................................ 7,965
<br />Below Parker Dam ...................................................................... 6,446
<br />Flow into Mexico .................h..................................................... 1,551
<br />
<br />Article III(d) of the Colorado River Com-
<br />pact provides that states of the Upper Divi-
<br />sion will not cause flow of the river at Lee
<br />Ferry to be depleted below an aggregate of
<br />75,000,000 acre-feet for any period often con-
<br />secutive years. In the past seven years, since
<br />beginning of storage in Lake Powell, ac-
<br />cumulation of storage in Colorado River
<br />Storage Project reservoirs, coupled with gen-
<br />erally low runoff, has resulted in a total flow
<br />at Lee Ferry of only 48,697,000 acre-feet, as
<br />shown below:
<br />
<br />Water Year
<br />
<br />Flow at
<br />Lee Ferry
<br />(Acre-Feet)
<br />
<br />1962-63..................................................................
<br />1963-64 ... ............. .................................................
<br />1964-65........................... .......................................
<br />1965-66..................................................................
<br />1966-<\7....................... ..........................................
<br />1967-68................................................... ...............
<br />1968-69..................................................................
<br />
<br />2,520,000
<br />2,427,000
<br />10,835,000
<br />7,870,000
<br />7,824.000
<br />8,358,000
<br />8,863,000
<br />
<br />Total..................................................................
<br />7- Year Average ....................................................
<br />
<br />48,697,000
<br />6,957,000
<br />
<br />In the next three years it will be necessary
<br />to release 26,303,000 acre-feet at Lee Ferry, or
<br />an average of 8,768,000 acre-feet per year, so
<br />that delivery will total 75,000,000 acre-feet
<br />for the ten-year period 1963-1972, The Bu-
<br />reau of Reclamation, by letter dated June 9,
<br />
<br />24
<br />
<br />1967, stated that it will provide for a flow of
<br />8,800,000 acre-feet a year at Lee Ferry from
<br />1969 through 1972.
<br />
<br />Since releases from reservoir storage and
<br />losses during the water year 1968-69 were
<br />less than inflow, total surface storage in
<br />major Colorado River Basin reservoirs in-
<br />creased by 3,223,000 acre-feet during the 1968
<br />-69 water year. As shown in Table 2, over 2
<br />million acre-feet of the total increase oc-
<br />curred in Lake Powell.
<br />
<br />Table 2
<br />CAPACITY AND SURFACE STORAGE OF MAJOR
<br />COlORADO RIVER BASIN RESERVOIRS
<br />(Thousands of Acre-Feet)
<br />
<br />Upper Basin
<br />Lake Powell .....
<br />Flaming Gorge ..........
<br />Navajo ........................
<br />Blue Mesa ..................
<br />Fomenelle ..................
<br />Morrow Point............
<br />
<br />Gross
<br />Capacity
<br />27,000
<br />3,789
<br />1,709
<br />941
<br />345
<br />117
<br />
<br />Active
<br />Storage
<br />End of
<br />Sept. 1969
<br />9,708
<br />1,826
<br />1,144
<br />720
<br />286
<br />41
<br />
<br />Change
<br />During
<br />Year
<br />+2,194
<br />-293
<br />+133
<br />+62
<br />-17
<br />-26
<br />
<br />Usable
<br />Capacity.
<br />25,002
<br />3,749
<br />1,696
<br />830
<br />345
<br />117
<br />
<br />Subtotal.............. 33,901 31,739 13,725 +2,053
<br />Lower Basin
<br />Lake Mead.................. 28,537 26,159 16.131 +1,113
<br />Lake Mohave ............ 1,818 1,810 1,441 +48
<br />Lake Havasu .............. 648 619 565 +9
<br />Subtotal.............. H,003 28,588 18,137 +1,170
<br />Total Both Basins .... 64,904 60,327 31,862 +3,223
<br />
<br />Plate 6 shows the combined active surface
<br />storage of Lake Mead and major Upper Basin
<br />reservoirs for the period 1935-1969. Lakes
<br />Mohave and Havasu are not included be-
<br />cause they are operated at relatively constant
<br />levels, In addition to surface storage, water is
<br />absorbed in areas adjacent to the reservoirs,
<br />At Lake Powell this absorption, or bank stor-
<br />age, was estimated to be about 4,200,000 acre-
<br />feet as of the end of water year 1969, or 36
<br />percent of the gross surface storage of 11,706,
<br />000 acre-feet.
<br />
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