?48 



THE IEKIGATION AGE. 



CORRESPONDENCE 



Seattle, Wash., May 17, 1911. 

 IRRIGATION AGE, 



Chicago, 111. 



Dear Editor: We would like to know the United States 

 government standard of water on irrigated projects per- 

 taining to the state of Washington, and also what one (1) 

 cubic foot of water per second of time for one hundred 

 and sixty acres of land figures in gallons per acre. We 

 would like to have you figure this out and publish the 

 answer in your next issue, if possible. 



Yours very truly, 



BANGHAM & FLETCHER. 



Regarding the first question as to the United States 

 government standard of water on irrigated projects in the 

 state of Washington, the Editor requests some more definite 

 specification, as he don't quite get at the meaning. 



As to the second query, what one cubic ft. of water 

 per second figures in gallons per acre for 160 acres of land : 

 One cubic ft. of water is about 7.5 gallons, so that if a 

 flow of 1 cubic ft. per second is maintained for 160 seconds 

 it will deliver 7J/2 gallons per acre. Hence the time of flow 

 is a very important element; it should be remembered, for 

 instance, that if a stream of one cubic ft. per second was 

 flowing for say 100 hours steady, it would deliver 100 X 60 

 X 60 = 360,000 cubic ft. of water; if this is divided by 

 160 gives 2,250 cubic ft. per acre, which, multiplied 

 by tVi, gives 16,875 gallons per acre; since 1 acre contains 

 43,560 square feet the depth of this water all over an acre 

 can be found as follows : First multiply 2,250 by 12, which 

 gives 27,000; then divide this by 43,560, which gives a depth 

 of .62 1 inches or about 54". Editor. 



WANTS INFORMATION. 



Scobey, Mont., May 21. 

 IRRIGATION AGE: 



I would like suggestions in your question department 

 regarding desert claim to be proved up by means of dam 

 and springs. What is best method of putting in dam when 

 there is a gravel subsoil? Also any other method of irri- 

 gating several hundred acres, not too expensive? 



Yours respectfully, 



HAROLD CLARK. 



There is hardly enough information in this letter on 

 which to base any specific advice. The conditions indi- 

 cated would suggest springs as a source of water supply 

 and possibility of forming a small reservoir which, by rais- 

 ing the water level, can be made available to irrigate some 

 land at a lower level. In the April issue of THE IRRIGATION 

 AGE is a good description and many good suggestions how 

 to build a satisfactory dam on land of gravel subsoil. The 

 point especially to be watched is that the sheeting is driven 

 deep enough to prevent the seepage water from rising under 

 the dam and cutting away the soil from under its founda- 

 tion. See article on page 856 in the April issue of THE IRRI- 

 GATION AGE for more definite information. Editor. 



FLOW OF ONE-EIGHTH CUBIC FEET PER 

 SECOND. 



Stamford, Texas, May 23, 1911. 

 IRRIGATION AGE: 



Please answer through your correspondence department. 

 I have a contract for 53.34 shares of the capital stock of 

 an irrigation company selling land under the Carey Act in 

 Idaho. Each share entitles me to ^ of a cubic foot of water 

 per second of time per acre. Is this ample water for irri- 

 gation where there is no rain, for all crops? Exactly how 

 much water is this? Under the Carey Act in Idaho what 

 recourse would I have should the contracted amount of 

 water not be supplied? Yours truly, 



E. L. MATTOON. 



A flow of water of Mi of a cubic ft. per second per 

 acre means a little less than a gallon (1 cubic ft. = 7.48 

 gallons) ; on this basis it means 60 gallons per minute and 

 3,600 gallons per hour and 86,400 gallons per day of 24 

 hours; if this is multiplied by 365 days it means 31,560,000 

 gallons per annum. Divide by 8 gives 3,942,000 cubic ft. 



of water, and as an acre contains 43,560 square feet, by 

 dividing 43,560 into 3,942,000 gives a depth of 90^ ft. of 

 water per acre per year, equivalent to a rainfall of 1,086 

 inches per annum. This is an enormous amount of water 

 and would be entirely too much, only for the fact that the 

 water is turned on only occasionally when wanted. Thus 

 if the flow occurs only 1 day per month on an average 

 it will amount to a depth of 36.2 inches over the area of 

 the acre. 



A SATISFACTORY AND INSTRUCTIVE 

 EXPLANATION. 



Phoenix, Arizona, May 23, 1911. 

 Editor of the IRRIGATION AGE : 



I have read with much interest your article in the May 

 number of your magazine on the Roosevelt dam in the Salt 

 river project. There are one or two inconsistencies in the 

 first part of the article, which is otherwise very accurate, 

 and a moment's consideration of the proofreader would 

 have shown the error. 



On the fifth line from the bottom you state that the 

 reservoir covers an area of 16,300 acres, etc.; that it is over 

 200 feet deep at the dam but the average depth does not 

 exceed 16 feet, and when the reservoir is full it contains 

 1,284,200 acre feet of water. The average depth is, there- 

 fore, about eighty feet. Later on in the article you call 

 attention to the fact that water is leaking through the 

 rocks around the dam. Quite a considerable leakage does 

 exist through the rocks around the dam, but unfortunately 

 your correspondent was not aware, perhaps, of the fact that 

 that this water is warm in fact, quite warm. Under the 

 reservoir, a mile or two above the dam, there existed some 

 large hot springs which, since the reservoir lias filled par- 

 tially with water, have been forced to take another path 

 and follow the crevices in the rocks issuing along the walls 

 of the canyon for about a quarter of a mile below the dam. 

 All the water is warmer considerably than the water in the 

 reservoir, and much of it is so hot immediately where it 

 issues from the rock as to be unbearable to the jhand. The 

 rocks forming the side wall of the canyon, dip upstream at an 

 angle of about twenty-five degrees so that, if the water fol- 

 lows the seams in the rock, it must pass under the dam 

 at a depth of from 300 to 500 feet below the bottom of 

 the dam. The sidewalls of the canyon, through the crevices 

 of which small streams of hot water are issuing, are quartz- 

 ite, and during the time in which there has been water 

 in the reservoir (over two years now), there has been no 

 increase in the flow and on one side of the canyon a very 

 material decrease. 



Very truly yours, 



Louis C. HILL. 

 Supervising Engineer. 



We are glad to thus hear directly from Mr. Hill, Super- 

 vising Engineer, giving such satisfactory and instructive facts 

 in relation to the Roosevelt dam, and our readers will, no 

 doubt, appreciate the same. Editor. 



THANKS, MR. COLLINS. 



San Antonio, May 19, 1911. 

 D. H. Anderson : 



You will please find enclosed two dollars. Please move 

 me up two years. I have taken your paper since its first 

 year and it is well worth . many times its price. I have 

 been interested in irrigation in Texas since 1872 and have 

 now, I think, the best 170 acre farm in the United States. 

 Can sell for $1,500 an acre. How is that for an irrigated 

 farm in Texas, where all plants have thorns and frogs have 

 horns ? Truly yours, 



F. F. COLLINS. 



FARMERS' INSTITUTE WORKERS' ANNUAL 

 MEETING. 



May 34, 1911. 

 Editor Irrigation Age: 



The next annual meeting of the American Associa- 

 tion of Farmers' Institute Workers will be held at Colum- 

 bus, Ohio, November 13 to 15, 1911. At the same place 

 and beginning November 15, will be held the annual meet- 

 ing of the Association of American Agricultural Colleges 

 and Experiment Stations. 



Notice is sent out thus early in order that farmers' 



