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<br />Wayne N. Aspinall Unit
<br />[Gunnison River]
<br />Blue Mesa Reservoir
<br />Morrow Point Reservoir
<br />Crystal Reservoir
<br />
<br />Water Year 1984
<br />
<br />The Wayne N. ASj?:inoll Unit, formerly the
<br />Curecanti Unit, tr'icludes Blue Meso, Morrow
<br />Point, and Crystal Reservoir. Blue Mesa
<br />pro....ides nearly all of the long.term
<br />regulation for all three powerplants.
<br />Morrow Point provides peaking power, and
<br />thus has highly variable releases. The
<br />primary function of the Crystal Reservoir is
<br />to reregulote the variable Morrow Point
<br />releases.
<br />
<br />Blue Meso Reservoir began water year 1984
<br />at elevation 7,509 feet and stored 740.000
<br />acre-feet. It was planned to fill Blue Mesa
<br />not higher thon elevation 7,51.4 feet in
<br />order to reduce the risk of using the
<br />spillway which was scheduled for air slot
<br />modification in the fall. The reservoir was
<br />lowered gradually to elevation 7.491 feet by
<br />January 1, 1984. The January 6, 1984,
<br />f.orecest of April through July runoff was
<br />1.30 maf or 180 percent of normal. This
<br />volume of proiected April through July
<br />inflow required that releases from Blue
<br />Mesa Dam be maintained at about 2,500 cfs
<br />through March 1984 and then increased to
<br />maximum powerplant capacity for the
<br />remainder of the runoff season. This
<br />would produce 0 sufficient drawdown to
<br />limit the peak ele.....ation of Blue Mesa
<br />Reservoir to 7,514 feet during the runoff.
<br />To accommodate releases of this magnitude
<br />from Blue Meso. Crystal Reservoir began
<br />discharging 600 ds through its river outlet
<br />works in _addition to maximum powerplant
<br />releases of 1,700 cfs. Above.normal
<br />January and February inflows caused the
<br />bypass to be increased to 900 ds in
<br />February and to 1,200 cfs in March even
<br />though the April through July runoff
<br />forecasts steadily declined to 152 percent of
<br />normal by March 6, 1984. Blue Mesa
<br />Reservoir was drawn down to about
<br />ele.....ation 7,.428 feet on April 16, 1984, in
<br />preparation for the spring runoff.
<br />
<br />The side inflow to Morrow Point and Crystal
<br />Reservoirs increased rapidly in mid-May
<br />which resulted in a significant decrease in
<br />Blue Meso releases in order to limit
<br />powerplant bypasses downstream. The
<br />inflow to Blue Mesa Reservoir also rapidly
<br />increased to over J6,000 cfs by May 25,
<br />1984. Releases, however, were held to a
<br />10
<br />
<br />minimum because of serious flood damages
<br />being incurred in Delta. Colorado, from the
<br />swollen North Fork of the Gunnison River.
<br />As the downstream flood danger subsided
<br />in late May, Blue Mesa releases were
<br />increased to maximum powerplant capacity
<br />and the outlet works were opened on May
<br />16, 1984, to 2,0')() cfs. This bypass
<br />discharge was gradually increased to its
<br />maximum by June 2.4, 1984, which resulted
<br />in a total maximum discharge of 7,6(JJ cfs
<br />from Blue Mesa Dam. This release slowed
<br />the rapid rise of Blue Mesa Reservoir in
<br />time to prevent having to use the
<br />spillway. As the reservoir stopped rising,
<br />the bypass releases were gradually reduced'
<br />and finally turned off on August 6, 1984.
<br />Blue Mesa's water surface hod increased a
<br />total of over 90 vertical feet in just 90 days
<br />to on elevation of 7,518 feet by mid-July.
<br />The reservoir elevation peaked at 7,518.6
<br />feet on August 27, 1984.
<br />
<br />The actual April through July runoff into
<br />Blue Mesa Reservoir was 1.374 maf or 190
<br />percent of normal. The total water year
<br />1984 inflow was 1.794 maf or 167 percent
<br />of normal. Releases from Blue Mesa Dam
<br />totaled 1.737 maf for the water year of
<br />which 381,000 acre-feet bypassed the
<br />powerplant.
<br />
<br />Morrow Point Reservoir operated at or near
<br />capacity between elevations 7,150 and 7,161
<br />feet. The April through July side inflow
<br />into Morrow Point Reservoir was 186,000
<br />acre.feet which was 315 percent of
<br />normal. A total of 1.954 mof was released
<br />during the water year of which 239,000
<br />acre.feet bypassed the powerplant.
<br />
<br />Crystal Reservoir also was operated at or
<br />near its capacity during water year 1984.
<br />The April through July side inflow to
<br />Crystal was 247,000 acre-feet which was
<br />280 percent of normal. A total of 2.276
<br />maf was released during t},e water year of
<br />'r'!"Jch_ 1_.027 mof _bypa.ss~d-,he po.werplant._
<br />During water year 1984 the minimum
<br />release was 1.700 cfs while 0 maximum
<br />discharge of 9,700 cfs occurred on June 19,
<br />198.4. The maximum discharge from Crystal
<br />Dam could hove been greater than 20,000
<br />ds had not Blue Mesa and Taylor Park
<br />Reservoirs moderated the peak inflow. The
<br />operoHon at these reservoirs hod significant
<br />beneficial impacts in reducing the flood
<br />damage along the Gunnison River near
<br />Delta, Colorado.
<br />
<br />Water Year 1985
<br />
<br />Assuming near average water supply
<br />conditions in water year 1985, Blue Mesa
<br />Reservoir is expected to reach a low of
<br />7,458 feet with a content of 360,000 acre-
<br />feet by April 1985. The reservoir is
<br />
<br />expected to reach 0 peak elevation of
<br />7,514 feet during the runoff. The
<br />remaining 5 feet of reservoir is planned to
<br />be kept vacant to reduce the risk of having
<br />to use the spillway during the heavy spring
<br />flows.
<br />
<br />Morrow Point Reservoir will operate at or
<br />near its capacity during the current year.
<br />Crystal Reservoir also will operate nearly
<br />full except for doily fluctuations needed in
<br />regulating the releases from Morrow Point
<br />and to meet downstream requirements for
<br />fish habitat and diversions through the
<br />Gunnison Tunnel.
<br />
<br />Assuming near overage inflow conditions,
<br />releases from Crystal Reservoir will be at
<br />maximum powerplant capacity of 1,700 cfs
<br />in addition to scheduled bypasses of up to
<br />1,000 cfs. Under reasonable minimum
<br />inflow conditions. releases will range from
<br />1,000 cfs to 1,700 cfs. With reasonable
<br />maximum inflows, releases would be at
<br />least 4,000 cfs and possibly higher.
<br />
<br />Reservoir
<br />
<br />Blue Mesa Active Storage.
<br />
<br />Acre-Feet
<br />
<br />EI. (Ft.)
<br />
<br />7519
<br />7438
<br />7393
<br />
<br />Maximum Storage
<br />Rated Head
<br />Minimum Power
<br />Surface Area (Full)
<br />Reservoir length
<br />(Full)
<br />Powerplant
<br />Number of Units
<br />Total Capacity
<br />
<br />Chart 3
<br />
<br />829,523
<br />249,395
<br />81,070
<br />9,180 Acres
<br />
<br />24 Mi les
<br />
<br />"Oo.s nol indud. 111.232 ocr.l..t 0' dllad ,'orag. b.low 7358
<br />1..1.
<br />
<br />2
<br />60,000 Kilowatts
<br />
<br />Morrow Point Active Storage.
<br />
<br />Maximum Storage
<br />Rated Head
<br />Minimum Power
<br />Surface Area (Full)
<br />Reservoir length
<br />(Full)
<br />Powerplant
<br />Number of Units
<br />Total Capacity
<br />
<br />117,025 7160
<br />79,805 7108
<br />74,905 7100
<br />817 Acres
<br />
<br />11 Miles
<br />
<br />"Don nor IrocIud. 165 ocr..I..1 01 dead Iloroge b.low 6S08 1,,1
<br />
<br />2
<br />120,000 Kilowatts
<br />
<br />Crystal Point Active Storage""
<br />
<br />Maximum Storage
<br />Rated Head
<br />Minimum Power
<br />Surface Area (Full)
<br />Reservoir length
<br />(Full)
<br />Powerplant
<br />Number of Uni1$
<br />Total Capacity
<br />
<br />17,573 6755
<br />13,886 6742
<br />10,619 6729
<br />301 Acres
<br />
<br />7 Miles
<br />
<br />'Ooe, nOI includ. 7,700 ocr..I.., 01 deod .Iora~ below 6670 '..1.
<br />
<br />1
<br />28,000 Kilowatts
<br />
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