FLOOD09658

• County: Rio Blanco
• Community: Meeker
• Stream Name: Sulphur Creek
• Basin: Yampa/White
• Title: Sulphur Creek Basin Hydrologic Investigation
• Date: 3/1/1992
• Prepared For: Rio Blanco
• Prepared By: CWCB
• Floodplain - Doc Type: Educational/Technical/Reference Information

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The lR-20 model computer routes runoff hydrographs for selected sub-basins at
designated design points. These design points. were placed at locations which were
representative for the basin runoff patterns. The 7.5 Minute Quadrangle Maps at a scale
of 1:24,000 were used to complement the field data for developing the input data for the
determination of the runoff patterns and characteristics and sub-basin hydrographs.

The rainfall values which were used were obtained from the "Precipitation-Frequency
Atlas of the Western United States", NOAA ATIAS 2, Volume ill for a 24 hour storm
event. The May-October precipitation values were used for the analysis. These values were
selected because the values are representative of a summer rainfall event which has been
the history of flood events for the basin. The rainfall values are shown in Table N. The
Type II storm distribution was used for the analysis.

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TABLE N
SULPHUR CREEK BASIN
RAINFALL VALVES
for
May - October
(in inches)

10-year
25-year
50-year
lOO-year

1.7'
2.0
2.2
2.4

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Note: Value adjusted for consistences of input data.

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The model input determinations for the Sulphur Creek Basin include:
o Soil Classification
Source: Soil Survey of Rio Blanco County Area Colorado, USDA Soil
Conservation Service dated May, 1982
o Vegetative Cover and Condition
Source: Urban Hydrology for Small Watersheds, lR 55 dated June,
1986, Tables 2-2a and 2-2d
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