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<br /> COLORADO BASIN
<br /> Basinwide Conditions Assessment:
<br /> The SWSI value of-2.1 indicates that the basin water SURFACE WATER SUPPLY INDEX
<br /> supply is considerably below normal. Snowpack measured S Co lariat)
<br /> "`v` °"'"
<br /> 71% of average on March 1, 1991. Precipitation for the 4_ ; 4
<br /> month was only 44% of normal, and is on a four month .- • I
<br /> decline. Flow at the key gaging station, Colorado River near a
<br /> 3
<br /> Dotsero,averaged 670 cfs as compared to the historic monthly ', - =4
<br /> average of 984 cfs. Base flows are critically low in tributaries ; 1- : ; -
<br /> to the Colorado River due to scarcity of low elevation i ° ',- r E" i .
<br /> snowpack and resulting low runoff. Basinwide reservoirs ', �� �'�
<br /> storage was 85%of average. Dillon Reservoir, Williams Fork >> - I
<br /> Reservoir, and Ruedi Reservoir have near normal storage o -2 h ; ' r
<br /> levels. Vega Reservoir, Rifle Gap Reservoir, Green Mountain '-
<br /> Reservoir, and Granby Reservoir have storage contents well -• , -�-� . - T .. �- .. ... m - -.
<br /> JANO1 JAIA3 JAIM3 JA"N JANOS JAN S JANO7 .1ANOS JA"M JMI00 JA"!1
<br /> below normal. Granby Reservoir contents (useable)measured Wee,,,7d,,,
<br /> 131,484 acre-feet on March 1, 1991,compared to the historic
<br /> seasonal average of 268,900 acre-feet, and a capacity of
<br /> 465,600 acre-feet.
<br /> Outlook: COLORADO RIVER NR. DOTSERO
<br /> Snowpack is likely to be low going into the 1991 n0''..TER'"''"
<br /> runoff season unless significantly above average snowfall is „°
<br /> received in the March-April period. Streamflow forecast is
<br /> lowest in the Williams Fork drainage above Williams Fork i 400
<br /> �Reservoir at 61% of average and highest in the East Fork + 3"
<br /> Troublesome Creek drainage at 77%of average. 3x,
<br /> J
<br /> T
<br /> ,dministrativeJManagement Concerns:
<br /> The "Dotsero" call (January 7, 1902 decree) to satisfy
<br /> the Shoshone Hydroelectric Power Plant water right of 1250 '30
<br /> cfs was temporarily adjusted down to 670 cfs since one of the is.
<br /> turbines is currently under repair and not operating. This soon pc., Coc Jan F.b wrcn
<br /> went into effect on March 1, 1991. This is allowing a number W,,,,,
<br /> a .!T C 1004) + OiM C 1/77] o AVG p 1.91
<br /> of upstream diversions to take water. It is expected that the
<br /> "Cameo" call (March 21, 1911 decree) will control the lower
<br /> Colorado River during the 1991 irrigation season.
<br /> Public Use Impacts: Colorado River Basin Reservoir Supplies
<br /> Snowmaking is playing an increasing role in winter .°
<br /> water use demands. These demands compete with the needs -
<br /> of hydroelectric power,municipalities,stock watering,storage, /7 7//,,,\ \
<br /> and maintaining minimum stream flows. Snowmaking rights i
<br /> are typically junior except in the case of minimum stream oo
<br /> + 30 \
<br /> flows. This water use duringlow flowperiods is a major §!
<br /> J
<br /> 43
<br /> concern relative to impacts on stream fisheries. 11,
<br /> a .", //"AlA
<br /> :,N,
<br /> ,o .//\ /\
<br /> . ,\ ,.
<br /> to..,mount.I n p...1 VIII I..i.FprIC
<br /> ® Avg. 2/2O COnt nIu ® 212V11 Con t.nt.
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