FLOOD00079

• County: Statewide
• Community: Nationwide
• Title: Guidelines for Determining Flood Flow Frequency Bulletin 17
• Date: 3/1/1976
• Prepared By: USWRC
• Floodplain - Doc Type: Educational/Technical/Reference Information

CONTENTS

I. Introduction..........

Page
1
2
3
3
3
4
4
4
4
4
5
5
6
6
6
6
7
7
7
8
8
9
9
9
14
14
14
15
16
17
18
18
19

II. Summary . . . . . . . . . . . .
A. Information to be Evaluated
B. Data Problems . . . . . . . . .
C. Determination of Frequency Curve
D. Reliability Applications
E. Potpourri .......
F. Appendix. . . . . . . .

III. Information to be Evaluated
A. Systematic Records . . .
B. Historic Data . . . . . . . . . .
C. Comparisons with Similar Watersheds
D. Flood Estimates From Precipitation

IV. Data Assumptions. . . .
A. Climatic Trends . .
B. Randomness of Events
C. Watershed Changes
D. Mixed Populations . . . . .
E. Reliability of Flow Estimates

V. Determination of Frequency Curve
A. Series Selection. . . . . .
B. Statistical Treatment . . .
1. The Distribution. . . .
2. Fitting the Distribution
3. Broken Record . .
4. Incomplete Record ..
5. Zero Flood Years . . . .
6. Mixed Populations .. .
7. Outliers. . . . . . . .
C. Refinements to Frequency Curve
1. Historic Flood Data . . . . . . .
2. Comparisons with Similar Watersheds
3. Flood Estimates From Precipitation.

vi