DWR_4151805

• Title: OCTOBER 1990 SWSI: COLORADO WATER SUPPLY CONDITIONS UPDATE, SURFACE WATER SUPPLY INDEX
• Year: 1990
• Document Type - Publications and Reports: SWSI Monthly Report

•
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COLORADO BASIN
Basinwide Conditions Assessment:
The SWSI value of-0.6 indicates that the basin water SURFACE WATER SUPPLY INDEX
supply is slightly below normal. Precipitation for the month 5 , `°'°"'°°Alva.9i1n of September was 118% of normal. Tributary flow is _ `
critically low with conditions being worst west and south of 4_ f = "
Glenwood Springs. Three Mile Creek near Glenwood Springs i`' r it
is experiencing an unprecedented no flow condition. At the 2~ 4.,I.__ < r i , r
release rate, there is only 20-30 days of storage � ,- r -: - .)--
current ;
remaining in the West Slope Users Pool. Cumulative flow at ° r 1' i k _ _.
the key gaging station, Colorado River near Dotsero, was _,_ ;,r ;� 0 ,�,�
approximately 35%below normal for the water year and only . -
about 15% above the minimum flow recorded in 1977. Flow ., "_" �-• C�'° �'
at this station for the month of September was near normal. -'-
Granby Reservoir is filling slowly but is relatively low. Dillon -• ,.0"0' '""1° �"'�-.
Reservoir, Williams Fork Reservoir, and Ruedi Reservoir " �A». '4',,,, � yw.. '
remain full while other storage facilities in the basin are
extremely low. Soil moisture conditions improved during the
month of September.
Outlook: COLORADO RIVER NR. DOTSERO
The Colorado River mainstream should have adequate 3.2 _ RAW"V _ -
water supplies available through the remainder of the 3 _
_.
irrigation season. Shortages will continue in the Grand Mesa z.I
and Grand Valley areas. The Granby Reservoir water level 2.4
will increase slightly but will drop later in the year as 4 _;
pumping to the Adams Tunnel increases. ./ ,.. . .
Administrative/Management Concerns:
The "river call" placed on the Colorado River on July i _ _ _ . ti______L___....--------
27, 1990, to satisfy the Shoshone Power Plant right will o• �-.--*"
likely remain through the winter months. The "Cameo call" 0.4 0.3 _
placed on the Colorado River on July 30, 1990, will be 0, ( - 1
curtailed on October 26, 1990 . Decreasing flow in the "�" ON Jan `'° 'oren '1 4l Aug s.oe
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Colorado River has placed a strong demand on storage ° .0.ow) t Lopvim A AG ° 1990
releases from Green Mountain Reservoir to augment flow. It
appears that total releases will not exceed the 66,000 acre-
foot pool allocated for West Slope depletions. Project water
at Vega Reservoir has run out.
Colorado River Basin Reservoir Supplies
Public Use Impacts: 130
Since August 15, storage release of 60-90 cfs have ,m r
been made from Ruedi Reservoir to the 15 mile stretch below '"°
the Grand Valley Canal for the endangered fish species in
that area. This effectively increases flows in the Fryingpan f
and Roaring Fork Rivers. This will continue through October .1
15, 1990. Vega Reservoir is extremely low. Rifle Gap b' «°
/"
.7/\\N
o v.:, °'
Reservoir level is below the boat ramp.
s
'°-2" /\
30
20-„,/ //.\\ \
Green~min q,..! .I I II.O Farm
® Avg. 1130 Cant nts ® 1/30110 Contents
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