UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 1026 



Contribution from the Bureau of Public Roads 

 THOS. H. MACDONALD, Chief 



Washington, D. C. 



May 16, 1922 



IRRIGATION IN NORTHERN COLORADO. 



By RoBEBT G. Hemi^hill, Irrigation Engineer. 



CONTENTS. 



Introduction 



Cache la Poudre Valley- 

 Meteorology 



Soils . 



TVater resources 



Seepage return 



Drainage conditions 



Exchange of water 



Page. 

 1 

 2 



5 



6 



10 



12 



Water rights 



Distribution from river 



Duty of the river 



Canal systems 



Gross duty for canals. 



Farm irrigation 



Reservoirs 



12 Summary and conclusions. 



Page. 

 13 

 19 

 24 

 26 

 42 

 51 

 69 

 79 



INTRODUCTION. 



Prior to the establishment of the Union Colony at Greeley, Colo., 

 in 1870, only a few primitive attempts at irrigation farming had been 

 made along the route of the Overland Trail in that State. The 

 small acreage of less than 1,000 acres which was then irrigated 

 for the purpose of raising native hay, vegetables, and grain for the 

 mining camps has increased in the half century which has since 

 elapsed to over 3,000,000 acres, yielding an annual revenue at cur- 

 rent prices of over $100,000,000. This great increase in acreage has 

 carried with it a corresponding development in irrigation practice 

 and in the customs and laws relating to irrigation. In fact, Colorado, 

 while maintaining a ranking in irrigation development second only 

 to that of California, has established laws and customs and 

 standarized practice to such an extent that the people of the State 

 have become in many respects the leaders in such development 

 throughout the Rocky Mountain region. In the aridity of its cli- 

 mate, elevation above sea level, topography, soils, and crops Colorado 

 bears a close resemblance to several neighboring mountain States. 

 It is not surprising, therefore, to find that the methods of preparing 

 land and applying water as well as the laws and administrative sys- 

 tems of the State have been adopted by other States having somewhat 

 similar physical conditions. The results of an irrigation investiga- 



74464°— 22 1 



