UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 194 



Contribution ttom the Office of Experiment Stations 

 A. C. TRUE, Director 



Washington. D. C. 



PROFESSIONAL PAPER 



May 10, 1915 



THE 



FLOW OF WATER IN IRRIGATION 



CHANNELS 



By 

 FRED. C. SCOBEY, Irrigation Engineer 



CONTENTS 



Introdoction 1 



Nomenclature * . . . 2 



Historical 2 



Necessary Field Data for Values of n . . 4 



Scope of Experiments 7 



Equipment and Methods Employed for 



Collecting field Data 7 



Correction for Velocity Heads .... 15 

 Elements of Field Tests to Determine Re- 

 tardatlon Factors in Kutter and Chezy 



Formulas 16 



Page 



Description of Channels 28 



The Use of Values of n 45 



Recommendations for Values of n for 



Different Kinds of Channels .... 47 



Estimation Charts 52 



Variation of n in the Same Channels . . 58 



Conclusions 60 



Acknowledgments ^61 



Appendix 62 



WASHINGTON 

 COVERNMKNT PRINTING OFFICE 



1015 



