29 



(^iittntitii iif irater <ipj>llf(l to Inndi^ ttmler High I/nie anuil, 1!)02. 



Duration of irrigation season .May 24-AugU8t 31 



Area irrigated acres. . 2, 3-^3 



"Water received by land . . .' acre-feet. . 12, 472 



Deptii of water used in irrigation feet.. 5. 32 



Deptli of rainfall during season" do 39 



Total depth of water received by land do 5.71 



The 5ivora*;(' How of tbo caiuil at Todds tliinio was ♦52. Jl cii))ic feot per 

 second, or 2,51 »*. miner's inches, j^Mvino- a duty of water of "Al acres per 

 cubic feet per second, or approximately 1 acre i)cr incli. 



The above valiu's are l)ased on the amount di\ erted from the river. 

 In order to determine tiiC amoiuit of water api)lied to the land, seepage 

 losses nuist be taken into consideration. During the season of 1902 

 seepaoe measurements were made on the High Linc^ canal, with a view 

 to determining the loss in diti'creiit sections of the canab In the follow^- 

 ing summary is given the result of the seepage test mach' in June, 1902. 



Seepage in first 10 niilen of High Line canal, ineasured June 24, 1902. 



[In cubic feet per second.] 



Discharge 0.5 mile below head gate 98. 67 



Discharge 1 mile tunnel 87. 47 



Loss in 10 miles 11. 20 



Loss per mile 112 



Percentage of loss 11. 35 



In this first 10 miles there are no diversions. The canal traverses a 

 steep sidehill almost the entire distance, gaining the top of the bench 

 near the point where the low^er measurement was made. On July 18, 

 1900, the seepage loss, measured in this same section when the dis- 

 charge was 114.5 cubic feet per second at the head, was found to be 

 12.9 per cent of the amount entering the head. The loss in the next 

 16 miles was determined June 25. The results appear in the following 

 table: 



Seepage loss from High Line canal hetiveen mileposts 11 and 27 June 25, 1902. 



[In cubic feet per second.] 



Discharge near 1 1 -mile post 89. 69 



Discharge near 27-mile jiost 19. 87 



Diversions in section 54. 71 



Total outflow from section 74. 58 



Loss in 16.5 miles - 15. 11 



Loss per mile : 92 



Percentage of loss per cent. . 16. 85 



« Rainfall, assumed to be same as at Government Weather Bureau station, Bozeman. 



