IRRIGATION IN THE ROCKY 

 MOUNTAIN STATES. 



THEIR AGRICULTURAL CONDITION. 



BY J. C. ULRICH, C. E. 



The Rocky Mountain region and its development under irrigation 

 is the subject of a publication just issued for free distribution by the 

 Irrigation branch of the Department of Agriculture. It was prepared 

 by J. C. Ulrich, an irrigation engineer of Denver, and describes par- 

 ticularly the States of Colorado, Idaho, Montana, Utah and Wyoming. 

 The bulletin explains how ditches are built and operated, its main 

 purpose evidently being to inform those to whom the subject is new 

 and strange, and thus enable them to avoid the costly mistakes to 

 which beginners in irrigation farming are liable. 



The difference is shown between ditches built and operated by 

 individuals, corporations or districts, and the difference of methods of 

 operation. The detailed organization and management of the canals 

 are described, especial attention being given to the duties of the 

 "ditch rider," the official with whom the farmer comes into most fre- 

 quent and intimate contact. His duties consist in patrolling the ditch 

 throughout the season of actual operation for the purpose of seeing 

 that the works are in good repair and to superintend the proper dis- 

 tribution of water to the various stockholders -or irrigators from the 

 system. Where a ditch does not exceed 12 or 15 miles in length one 

 ditch rider is expected to patrol its entire length, but upon more ex- 

 tensive systems several may be required to perform these duties. 



The different methods of applying the water to the land (flooding, 

 furrow, and compartment systems) are described, and the conditions 

 under which each is especially applicable are explained. The advan- 

 tage of reservoirs in equalizing the flow of streams and in increasing 

 the irrigable area is pointed out. The quantity of water necessary or 

 used for irrigation fluctuates during the irrigating season, but unfor- 

 tunately the period of maximum use does not usually coincide with 

 the period of maximum flow of the streams. An adequate system of 

 storage will not only protect irrigators from the variation in supply 

 from month to month, but assist in reducing the fluctuations from 

 year to year. It will enable the floods of years of large discharge to 

 be held back for the years of drought. Reservoirs are simply a sec- 

 ondary means of utilizing waters which otherwise run to waste, and 



