SWSIReportJune2008

• Title: Colorado Water Supply Conditions Update
• Date: 6/26/2008
• Description: Water Availability Task Force Meeting Presentation
• Basin: Statewide
• Drought Mitigation - Doc Type: Presentation

SAN JUANIDOLORES BASIN
Basinwide Conditions Assessment
The SWSI value for the month was +1.6. Flow at
the gaging station Animas River near Durango was 2570 cfs,
as compared to the long-term average of 2219 cfs. Storage
in McPhee, Vallecito, and Lemon reservoirs totaled 107% of
normal as of the end of May.
Flows at the Animas River at Durango averaged
2,570 cfs (111 % of normal) with a maximum average daily
peak flow of 5,982 cfs on May 21St. The Dolores River at
Dolores averaged 2,022 cfs (117% of normal) with a
maximum average daily peak flow of 4,141 cfs on May 21St.
The La Plata River at Hesperus averaged 164 cfs (98% of
normal) with a maximum average daily peak flow of 365 cfs
on May 21St. Precipitation in Durango was 1.72 inches for
May which is above the 30-year average of 1.20 inches.
Precipitation to date in Durango, for the water year, is 15.33
inches which is above the average of 12.49 inches.
Temperatures were near normal for the month. Durango
was 0.3° below its 30-year average high and 0.5° below the
30-year average low.
At the end of the month Vallecito Reservoir
contained 80,090 acre-feet compared to its normal contents
of 87,378 acre-feet (92% of normal). McPhee Reservoir was
up to 365,353 acre-feet compared to its normal contents of
318,941 acre-feet (115% of normal), while Lemon Reservoir
was up to 34,220 acre-feet as compared to its normal
content of 29,849 acre-feet (115% of normal).
Outlook
Temperature and precipitation were at normal levels
for the month. The 3rd week in May brought very warm
temperatures and rising rivers only to be slowed at the end of
the week with a cold front that brought a foot of snow to the
high mountain peaks. The NRCS data on May 31, 2008
reported asnow-water-equivalent of 100% of average in the
San MiguellDoloreslAnimassnd San Juan basin
AdministrativelManaaementConcerns
The compact period on the La Plata between
Colorado and New Mexico began on February 15t". New
Mexico placed a call starting on April 30t" for half the flow at
the upper index gage up to 80cfs.
Public Use Impacts
The start of run-off season has saturated the ground
and started many land slides in the area. One notable slide
within the region is located approximately 11 miles north of
Pagosa Springs on the East Fork San Juan River. Xcel
Energy first noticed the slide on May 2 when the slide
severed their 8-in gas line. Throughout the month of May the
slide has been moving at a rate of about 4-ft per day. At the
bottom of the slide is the East Fork San Juan River. High
flows in the river have been scouring the slide material down
stream and maintained the river channel but diversion
structures along the river must fight to keep their head gates
from silting in. Water Resources personnel installed a
stream gage below the slide to monitor flows in the event the
slide was to block the entire flow of the river.
Jun-08
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