Fl"i:i. Dii.s i-(iK Ti'MP Ikr[(',.\T[on 421 



foot lift and J^.>4 per aero on an SO-foi^t lift.''' The eost for cotton is 

 abont three-fourths of these amounts, and for sinj^le-croppcd land 

 about one-iialf of the amounts. These figures state the cost of the 

 ])umped water and do not include the cost of distributing- and applying 

 the water. 



It may be of value to compare these costs with the cost of water 

 under gravity systems. For the year ended October 1, 1920, the 

 charges on the Salt River project were $3.90 per acre for 3 acre-feet 

 and S4.90 per acre for 4 acre-feet. The corresponding figures for tiie 

 current water year are $6.40 and $7.40. including a special assessment. 

 To these figures should be added about $4 per acre to cover the interest 

 on the capital invested in the project. ( In the case oi the v^alt River 

 and other Reclamation Service projects this interest is remitted. ) 



It appears that pump irrigation, where the pumping lift (that is, 

 the depth to water level plus the drawdown) does not exceed 40 feet, 

 can compete measurably well with gravity irrigation. I'ndoubtedl)' 

 pump irrigation with low lift can continue without interru))tion through 

 a period of price depression in farm crops. P.ut where the i)umping 

 lift is much above 40 or .^0 f^et. it is apparent that there must be a 

 fairly wide margin of profit in farming to make pumping profitable 

 with the common type of plant. This statement nuist be modified 

 somewhat in the case of plants already in operation; for it may be 

 better to operate a high-lift |)lant to a limited extent through a period 

 of low prices, devoting the land to the higher-iiriced cro])S. than to 

 suffer the loss of the iu\'estment already niade. \\'\[h citrus fruit>. 

 grapes, melons, lettuce and some other crops, the value of which is 

 liigh, the cost of t!ie labor of production exceeds the cost of irrigation ; 

 the cost of fuel oil. therefore, may not be the controlling factor in the 

 case of crops of high value. With a wide margin of ])rofit in farming, 

 there is op])ortunity for inim|)ing on high lift. There is a personal 

 equation involved also: under the same controlling factors, some 

 farmers who arc thrifty and possess good business abilit}-. an 1 are not 

 hampered b}' lack of ca])ital, can show a profit where other farmers 

 fail. 



ALTERNATIVE SOURCES OF ROWER 



With gas oil at 18 cents a gallon, it is well to study the alternative 

 sources of power for pumping. 



*The basis jiiiil niofliofl of ooiiipntiiis pnnipina: posts, and tlie .issiiniptions required, are 

 sliitc'l in ili'tiiil in Bill, 74 of this Station, and tliorefore arc not repeated liore. 



