TABLE 4-4. COMPARISON OF STREAMFLOUS WITH CLAIMED RIGHTS AND ESTIMATED 

 ACTUAL WATER USE FOR IRRIGATION 



Subbasin 



Average 



Annual 



Flow 



cfs AF 



Adjudication Claims 



for Irrigation 



(pre-1973 rights) 



Acres cfs AF 



Estimated Actual 

 Acreage in use in 

 1980 

 Acres AF 



Upper Clark 



Fork* (above 



Hilltown) 1.633 1,183,000 



Blackfoot 1,402 1,016,000 



Bitterroot 2,486 1,801,000 



210,210 

 238,210 

 510,252 



Flathead** 12,388 8,979,000 110,210 



Lower Clark ' 



Fork* (from I 



MiUtown I 



past Noxon I 



Rapids) 21,020 15,230,000 I 56,730 



3,385 996,068 



80,953 1,319,765 



106,930 2,308,270 



126,354 55,677,877 



1,590 357,763 



28,821 

 100,681 

 112,755 

 174,917 



413,000 

 106,180 

 483,710 

 711,700 



31,659 345,110 



* Adjudication claim figures for these basins adjusted to eliminate most duplication of 

 claims for the same acreage. 



** Adjudication claims submitted for Flathead Indian Irrigation Project listed flow rates 

 and volumes, but no acreages. 



Sources: USGS 1987; DNRC 1988a; DNRC 1986; Elliott 1986. 



4-17a 



