BOARD00154 ‎(2)‎

• Board Meeting Date: 3/13/2007
• Description: ISF Section - Notice of 2008 Instream Flow Recommendations and Summary of ISF Workshop
• Board Meetings - Doc Type: Memo

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Table 3. Summary statistics of mean daily discharge through Bear Creek. For each month, the discharge
that 50% of flows were equal to or greater than is highlighted. Yellow indicates summer months, orange
late summer months and blue indicates winter months.

Station: Bear Creek near the Bear Creek Diversion 10: CSU gage 1291
Prameter: Discharge Statlstic: Mean Daily Discharge
Year: portions of 10/1/49 - 9/30/06 Latitude: 38: 49: 26
State: Colorado Longitude: 104: 53: 39.7
County: EI Paso Elevation: -6250 ft
Drainage Area: 6.61 mi2
Monthl Statistics
Jan Feb Mar A r Jun Jul Au Od Nov Dec Annual
# days 1019 930 1021 987 988 1022 1020 1018 988 1017 12015
Avg Day 1.29 1.26 1.40 2.31 3.90 2.57 2.71 1.67 1.52 1.36 2.20
Max Day 4 4 4 29 29 19 15 5 4 3 29
Min Day 0.49 0.04 0.20 0.37 0.37 0.49 0.55 0.49 0.42 0.01 0.01
# months 33 30 33 32 32 33 33 33 33 33 30
Sdev Month 0.58 0.50 0.53 1.11 5.13 2.07 1.90 0.87 0.72 0.59
Skew Month 0.84 0.80 0.72 0.79 3.24 1.61 1.24 0.92 0.84 0.76
Min Month 0.56 0.54 0.53 0.76 0.66 0.64 0.72 0.55 0.58 0.57
Max Month 2.75 2.51 2.64 4.81 26.63 9.59 8.29 4.10 3.32 2.82

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Percentiles.
1 % 2.78 2.59 3.40 6.80 29.47 29.46 11.62 9.02 5.48 4.28 3.40 2.98 13.44
5% 2.40 2.40 2.40 5.36 16.18 14.68 6.65 6.56 4.51 3.20 2.88 2.59 5.74
10% 2.31 2.03 2.03 4.21 10.16 8.78 5.48 5.66 3.83 2.88 2.59 2.31 4.04
20% 1.69 1.69 1.78 2.98 6.65 4.53 4.05 4.51 3.19 2.40 2.18 1.86 2.68
50% 1.95 2.40 2.03 1.61 1.86 1.53
80% 0.78 0.78 0.84 1.24 1.27 1.20 1.03 1.08 0.92 0.92 0.89 0.83 0.94
90% 0.68 0.72 0.75 0.96 1.06 0.87 0.81 0.89 0.77 0.82 0.81 0.77 0.78
95% 0.59 0.67 0.68 0.79 0.88 0.73 0.66 0.78 0.64 0.55 0.63 0.59 0.68
99% 0.54 0.50 0.57 0.69 0.67 0.59 0.59 0.61 0.50 0.54 0.54 0.55 0.55
. Percentiles estimate the value (discharge) in the record associated with a given percentile. They provide an estimate
of the percentage of days on which a given flow is exceeded. Percentiles were calculated using the PERCENTILE
function in MicroSoft Excel.

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