FLOOD02408

• County: Statewide
• Community: Nationwide
• Basin: Statewide
• Title: Design Hydrographs for Very Small Wathersheds from Rainfall
• Date: 7/1/1962
• Prepared By: USDA Hydrograph Laboratory, Civil Engineering Section Colorado State University
• Floodplain - Doc Type: Educational/Technical/Reference Information

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Chapter

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CONTENTS - continued

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DISCUSSION OF RESULTS . , . . . , . . . . . , . . , . . , . . . ,

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Modifying Influences Upon the Coefficient of Determination .
Typical Results from an Entire Group . .
Selection of Best Three-Variable Groups.
Prediction of Total Runoff Volume. W. .

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Physical significance of- variables selected.
Comparison with next best group of variables
Final regression equation.
Predicted versus observed W

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Prediction of Hydrograph Peak, qo .

Physical significance of variables selected.
Comparison with next best groups of variables.
Predicted versus observed qo

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Prediction of Recession Parameter, G

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Physical significance of variables selected.
Comparison with next best groups of variables
Predicted versus observed G . . . . . . . .

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Conventional Versus Statistical Rainfall Parameters
Some Successful Predictions of Hydrographs. . . .
Limitations in Accurately Predicting a Hydrograph

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MEANS OF PREDICTING A HYDROGRAPH, . , . . .

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Obtaining Parameters for Hydrograph Model.
Calculation of Hydrograph Model
A Sample Problem

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Solution . .

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SUGGESTIONS FOR FURTHER RESEARCH

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Larger and More Selective Sample Needed.

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Degrees of freedom should be increased
Small floods should be excluded from the study
Larger range in watershed sizes possible

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Watershed Response Characteristics. . . . . . .
Need for Statistical Test in Fitting Hydrograph Models
Simplification of Practical Application Desired . . . .
Physical Laws Should Provide Form of Regression Equations
Probability Aspects Concern Designers
National Study of Rainstorms is Needed

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SUMMARY. , , .

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BIBLIOGRAPHY

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APPENDIX, , , .

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