378 golze. PROBLEMS OF IRRIGATION CANALS [Ch. 21 



ject. A book should be prepared to bring all information together 

 from the Kennedy formulas of India to the latest data available on 

 sedimentation in the canals of the Unted States. Economic formulas 

 to develop the value of watershed treatment, lining of canals, and im- 

 provement of cleaning machinery are urgently needed. 



In conclusion, the problems of sedimentation in irrigation canals are 

 not insurmountable. The causes and effects are generally known. 

 How to keep silt out of irrigation water and how to reduce the cost of 

 removal of sedimentation are problems for geologists and engineers. 

 Once their reports are available, the problem becomes a matter of 

 money, personnel, and time, balanced in total against the cost of letting 

 Nature take her course unchallenged. Much remains to be done to 

 lower 'the cost of removing silt by improving the design of desilting 

 basins, by developing low-cost canal lining, and by improving cleaning 

 machinery. With the cost of silt removal frequently exceeding 15 per- 

 cent of the operation and maintenance budget, or over 3.5 million 

 dollars annually, it takes a sufficient sum out of the pockets of farmers 

 each year to justify further research and expenditure of public and 

 private funds to continue and carry forward this specialized field of 

 sedimentation. 



REFERENCES 



A limited bibliography has been prepared on sedimentation of canals. Much 

 of the bibliography on the subject of sedimentation in general contains reports, 

 information, and data of interest or applicable to sedimentation of canals. To 

 list all such material would duplicate other bibliographies and confuse rather 

 than help. The following list contains all recent material known to exist that 

 directly applies to the subject. 



American Society of Civil Engineers (1925). Report of committee on silt 



problems: Proceedings, March 1925, pp. 151, 152. 

 Dowd, M. J. (1930). How the Imperial Irrigation District meets its problem of 



silt deposition and erosion: Engineering and Contracting, p. 436, Dec. 1930. 

 Forester, D. M. (1939). The Imperial Dam, All-American Canal System, Boulder 



Canyon Project: Reclamation Era, p. 28, Feb. 1939. 

 Fortier, S., and Blaney, H. F. (1928). Silt in the Colorado River and its rela- 

 tion to irrigation: U. S. Dept. Agr., Tech. Bull. 67. 

 Fortier, S., and Scobey, F. C. (1926). Permissible canal velocities: Trans. Amer. 



Soc. Civil Engrs., Paper 1588, vol. 89, p. 940. 

 Golze, A. R. (1946). Lower cost canal lining program: Reclamation Era, Aug. 



1946. 

 Houck, I. E. (1928). Sand problems at Franklin Canal intake, Rio Grande 



Project: Western Construction News, p. 712, Nov. 25, 1928. 

 Iowa University (1938). Transportation of silt and detritus: Abstract of articles. 



For titles see list of references in Chapter 20. 



