Board Meeting 10/01/1987

• Board Meeting Date: 10/1/1987
• Description: CWCB Meeting
• Board Meetings - Doc Type: Meeting

.

the following methods depending on the length
of systematic records available: statistical
analysis or regional regression analysis of
stream gage data, including historic flood
data; comparisons with similar watersheds; or
flood estimates using hydrologic models and
precipitation records (synthetic analysis).
All available streamflow data from the
drainage basin and adjacent basins shall be
inventoried and documented.

a. When at least 50 years of streamflow
records are available, a statistical
analysis of the individual streamflow
record and/or a regional regression
analysis of the data shall be made to
determine the flood peaks of selected
recurrence intervals. The following
methods, and any other methods approved by
the Board, are acceptable in a stochastic
approach:

1) "Guidelines for Determining Flood Flow
Frequency," Interagency Advisory
Committee on Water Data, Bulletin
#17B, Revised March 1982.

.

2) "Manual for Estimating Flood
Characteristics of Natural-Flow
Streams in Colorado, Technical Manual
I," U.S. Geological Survey, 1976.

3) "Estimation of Natural Streamflow
Characteristics in Western Colorado,"
U.S. Geological Survey, 1985.

4) "Rainfall-Runoff Modeling and
Preliminary Regional Flood
Characteristics of Small Rural
Watersheds in the Arkansas River Basin
in Colorado," U.S. Geological Survey,
1981.

5) "Techniques for Estimating Regional
Flood Characteristics of Small Rural
Watersheds in the Plains Region of
Eastern Colorado," U.S. Geological
Survey, 1987.

b.

When from 25 to 50 years of
records are available, the
analysis shall include a

streamflow
hydrologic
statistical

.

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