36 BULLETIN 614, U. S. DEPABTMENT OF AGBICULTUBE. 



In the North Yakima district the principal sources of water supply 

 for irrigation are the Naches River and Cowiche Creek. The water 

 is brought to various parts of the district through canals or ditches, 

 from which it is led through open ditches to the individual ranches, 

 where it is distributed through the orchards by means of furrows. 

 (See PL VI.) 



Private pipe lines for the purpose of conserving as much water 

 as possible have been installed in some instances by individual 

 growers, particularly on the higher lands in the Nob Hill district, 

 and there is a growing tendency on -the part of the ranchers in the 

 North Yakima district to follow this custom. This practice has 

 nothing to do with the general maintenance of the canal as a whole, 

 and the expense, which obviously will vary greatly, is borne entirely 

 by the individual owners. In this study such an investment is 

 considered as part of the land and improvement value. 



The basis of water distribution under the different ditches varies 

 from 33 to 80 acres per second-foot, and all stockholders under a 

 given canal pay exactly the same assessments for the same amount 

 of water. In some instances growers may use less water per acre 

 than usual on a larger amount of land — that is, one-half inch (miner's) 

 per acre instead of 1 inch per acre. This, however, is the excep- 

 tion. The customary rate of distribution is as given above in the 

 second-foot. 



In the Zillah district the majority of ranchers received their 

 supply of irrigation water through a Government canal, known 

 locally as the Sunnyside Canal. The water is delivered from the 

 main ditch through open ditches or wooden flumes to the ranches. 

 Flumes are often used in the orchards and usually are placed along 

 the higher parts or ridges of the land so that the water may be dis- 

 tributed more easily throughout the orchard. 



These flumes in the orchard are temporary and can be removed 

 to permit cultivation or other orchard operations. Usually they 

 are made of 8- to 12-inch boards, \ to 1 inch thick, and of varying 

 lengths. Along these boxlike forms or flumes holes are made through 

 which the water is allowed to flow for distribution. These holes 

 usually are covered with a small piece of tin or lath, which is used to 

 regulate the flow of water. There is a tendency in some instances 

 in this district to substitute underground piping for open ditches 

 and flumes. The water in both the North Yakima and Zillah dis- 

 tricts is distributed through the orchard by means of furrows. Very 

 few orchardists in the valley practice the flooding method. 



The maintenance charge or water tax may vary greatly from year 

 to year. Often high assessments are made for permanent improve- 

 ments or to cover the expense of litigation. The ranchers in the 

 North Yakima district from whom data were obtained paid annually 



