ISFAPPC01711

• Case Number: 05CW0215
• Stream Name: Horsefly Creek
• Watershed: San Miguel River
• Water Division: 4
• Water District: 60
• County: Montrose
• Instream Flow App - Doc Type: Supplemental Data

Precipitation Data
Staff reviewed local precipitation data sets from 2 different sites located around the Horsefly
Creek Drainage (see Precipitation Data in Appendix C). These sites include Norwood (1931-
1999) and Placerville (1947-1999). Table 3 shows the water year and the percent of average
precipitation recorded at each site.

Table 3: Precioitation Data as a percenta!!e of Avera!!e.

Water Year
1975
1976
1977
1978
1979
1980

Norwood
85%
72%
88%
110%
77%
?

Placerville
139%
88%
96%
102%
140%
130%

Table 3 shows the precipitation recorded at these sites were average to above average for the
time period 1975 - 1980. It is staffs opinion that the 5 years of stream-flow data analyzed is
representative of average to slightly above average water-years.

Existing Water Right Information

Staff has analyzed the water rights tabulation and consulted with the Division Engineer Office to
identify any potential water availability problems. There are no decreed surface diversions within
this reach of stream. Based on this analysis staff has determined that water is available for
appropriation on Horsefly Creek, between Sheep Creek and the San Miguel River, to preserve
the natural environment to a reasonable degree without limiting or foreclosing the exercise of
valid existing water rights.

CWCB Staff's Instream Flow Recommendation
Staff recommends the Board form its intent to appropriate on the following stream reach:

Seament: Confluence Sheep Creek to San Miguel River

Upper Terminus: Sheep Creek at
(Latitude 380 14' 29") (Longitude 1080 14' 35")
Lower Terminus: San Miguel River
(Latitude 380 12' 20") (Longitude 1080 18' 44")
Counties: Montrose
Length: 5.0 miles
USGS Quad(s): Sanbom Peak, Norwood
Flow Recommendation: 13.1 cfs (June 15th - July 14th)
3.25 cfs (July 15th - June 14th)

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