tied together through transformers and operated as one large distributing net- work, 

 into which power is fed through each of the plants, and from which power is taken 

 by numerous sub-stations, varying in size from the Great Falls Power Company's 

 sub-station at Butte, having a capacity of 21,000 kilowatts, down to the lowest 

 standard high-voltage sub-station of 250 kilowatts. Almost 2,000 miles of trans- 

 mission line are in operation, a considerable portion of which is steel tower line. 



Miles 



Steel tower lines, 110,000 volts 282 



Steel tower lines, 50,000 volts 60 



Pole lines, suspension insulator type, 110,000 volts : 375 



Pole lines, suspension insulator type, 50,000 to 100,000 volts 576 



Pole lines, pin type, 11,000 to 60,000 volts 571 



Total 1,864 



Storage Reservoirs. 



The ideal generating system must have an even flow of water to its turbines, 

 but this cannot be obtained if the natural flow of the river is depended upon. The 

 low water stage of the river limits the output that can be marketed continuously. 

 For this reason reservoirs are provided at each of the plants and in addition the 

 great Hebgen reservoir has been built on the Madison River, to control the supply 

 on both the Madison and Missouri Rivers. A summary of the reservoirs follows: 



Area, 

 acres 



Hebgen reservoir, on Madison river ! 13,400 



Madison reservoir, on Madison river 4,030 



Canyon Ferry reservoir, on Missouri river 4,570 



Hauser Lake reservoir, on Missouri river 5,470 



Big Hole reservoir, on Big Hole river . 

 Rainbow reservoir, on Missouri river .. 



Great Falls, on Missouri river 



Thompson Falls, on Clark's Fork river 



210 

 120 

 450 

 500 



Holter reservoir, on Missouri river 5,005 



Total 



Acre 



feet 



322,000 



21,000 



36,000 



54,000 



1,650 



1,000 



5,500 



5,500 



89,000 



Cubic feet 



14,000,000,000 



915,000,000 



1,570,000,000 



2,350,000,000 



70,000,000 



40,000,000 



240,000,000 



240,000,000 



3,850,000,000 



23,275,000,000 



Many Sites Undeveloped. 



Only a small portion of the available water power in Montana has been de- 

 veloped. In addition to the plants already built and in operation, there are a large 

 number of large power sites and numberless smaller ones ready for development 

 as soon as the demands for power increase and there is available capital for their 

 construction. Although these possible developments are located in all parts of the 

 state, the larger possibilities exist in the northwestern section of Montana, where 

 the waters of the Flathead, the Kootenai river and other large streams will, when 

 harnessed, furnish more than 500,000 horsepower. The power site at the mouth 

 of the Flathead lake, which is one of the most feasible in the state, has been 

 reserved by the government in connection with the reclamation system covering a 

 portion of what was formerly the Flathead Indian reservation. A number of 

 smaller power sites have also been reserved, while many others are under private 

 ownership. 



