AZ vs. CA:02 California Exhibits, Vol II; Nos. 58-113A

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Daily evaporation Depths in inches.______Authority. India, Ganges Canal, 0.15 mean for year, \ Maj. Allan Cun- ( ningham R. E. Northern India, 0.5 max. for summer \ Dr. Murray 1 Thompson. Spain, Madrid, 1867, j 0.178 mean, S George Higgin 1 0.435 max. for July, ( M. Inst. C. E. Northern Italy, 0.083 to 0.20 Baird Smith Colorado, 0.088 to 0.16 \ Walter H. \ Graves, C. E. Utah, Fort j 0.112 mean, ] F. H. Newell Douglas, 1890 { 0.245 max. for July, \ U. S. Geo. Sur. California, Kingsburg 0.126 mean 4 years, \ State Engr's. Bridge, {Department. Arizona, Gila j 0.25 mean, F. H. Newell Basin, (assumed) ( 0.42 max. for Aug. From this data, it would seem that I am amply safe in the following assumptions for our canals, mean daily evaporation, 0.25; maximum 0.75 and mean max. for hottest month 0.6 of an inch. At El Rio, we will return a large volume of water to the river, hence the loss above El Rio does not concern us. The area of the water surface of the main canal, below El Rio, is approximately 43,814,000 square feet; the area of the branches and distributaries should not exceed 65,721,000 square feet. On this basis, the loss from the main canal will be: Mean for year, 10.56 cu. ft. per sec, or 0.53% of full supply " hottest month, 25.35 " " " " " 1.27% " " " Maximum, 31.69 " " " " " 1.58% " " The loss from main canal and distributaries, Mean for year, 26.40 " " " " " 1.32% " " Mean for hottest month, 63.39 " " " " " 3.17% " " " Maximum, 79.20 " " " " " 3.96% " " " seepage The loss from seepage is usually controlled by two factors, the structure of the soil and the amount of silt carried in the water. If the soil is porous, water will pass through it