THE IKRIGAT10N AGE. 



371 



Government Completes Gunnison Tunnel 



Greatest Undertaking in History , of Irrigation Channel* Penetrates]3Mountain^Base 



More than 150,OOOjAcres Reclaimed.^ 



On July 6, when workmen tunneling in opposite di- 

 rections through the base of a mountain; the peak of which 

 towered two miles above, touched drills and removed the 

 last barrier of granite, the government had completed the 

 Gunnison tunnel, the most gigantic irrigation feat in 

 history. 



Late in September, with fitting ceremonies and the 

 presence of statesmen and scientists, the water will be 

 turned into this tunnel from the Gunnison River and as it 

 rushes through the base of the mountain to the arid fields 

 beyond, it will reclaim to agriculture and industry a tract 

 of 150,000 acres. 



Whatever credit belongs to the achievement of this 

 great undertaking may be given to government engineers. 

 Two previous efforts, first by the State of Colorado, in 

 which the land is located, and second, by a contractor, 

 working under direction of the Reclamation Service, ended 

 in failure. After long deliberation and extensive surveys 

 the government, through its reclamation department, then 

 started the work that has ended in complete success. 



In length and the volume of water transmitted, the 

 Gunnison tunnel is the greatest in existence today. It is 

 approximately six miles long, has a finished cross-section 

 of lOJ^xU^ feet, and will carry 1,300 cubic feet of water 

 per second. The walls will be cement lined throughout 

 and there will be generated about 10,000 horse power at 

 the fourteen intermediate drops. The total cost is esti- 

 mated at from $3,500,000 to $4,000,000. 



Since February, 1905, when the government had com- 

 pleted its survey and started active work on the tunnels, 

 from 500 to 800 men have been employed in three shifts. 

 Two villages of considerable size have been established 

 near either end. These were under government control 

 and were largely for the accommodation of workmen. 



While access to the shaft head from the Uncompahgre 

 Valley was easy, most troublesome obstacles confronted 

 engineers in making way for the beginning of work from 

 the Gunnison River side. Waters in the stream, confined 

 to a narrow channel between the mountains, rose at fright- 

 ful speed during the flood season. So precipitous were 

 the walls of this canyon that a road to the head of the 

 tunnel must be cut from the solid granite of the mountain 

 before workmen and machinery could reach the operating 

 point. This road is twenty-three miles in length and at 

 certain points the grade exceeds twenty-three per cent. 

 Heavy machinery and instruments for use at this end were 

 transported with the utmost difficulty. So great was the 

 flow of water, encountered in penetrating the mountain 

 from this direction that immense pumps, capable of hand- 

 ling 750,000 gallons each twenty-four hours, were required 

 for constant operation. 



Unusual difficulties were met during the course of the 

 work. Because of the volcanic structure of the mountain, 

 interior lakes and streams were tapped and penetrated. 

 Hot waters, quicksands, gas and various other obstacles 

 presented barriers to continuous work, and demanded en- 



gineering ability and resource to be overcome. Choke 

 damp delayed work for three weeks at one time and forced 

 the construction of a ventilating shaft nearly 700 feet 

 in depth. More than 500 feet of the tunnel were driven 

 through a fossil formation, yielding so readily to force 

 that special timbering was necessary. 



In the progress of the work it was necessary to con- 

 struct two sections of electric railroad and a telephone 

 exchange. An immense power plant for producing elec- 

 tricity for use in drilling and operating the electric line 

 was constructed by the government. 



From the Uncompahgre end of the tunnel the waters 

 will be conducted to the Uncompahgre river, a distance 

 of twelve miles, through a canal in which there is a drop 

 of 214 feet. Power plants will be built at fourteen points 

 along this canal and electricity thus generated will be 



View of Gunnison River and Deep Gorge Through Which it Courses. 



In the Foreground, Power Plant near East Mouth of 



Gunnison Tunnel. 



used for commercial purposes in the valley. Laterals and 

 ditches completed by individuals in their efforts to lead 

 water to certain parts of the valley are now under con- 

 trol of the government. These will be welded into a com- 

 prehensive system for distributing the flow equally to all 

 parts of the valley. New canals will be built, thus bring- 

 ing under cultivation much of the upper mesa land, which 

 is red, sandy soil, unequaled for the cultivation of fruit. 

 Under irrigation Uncompahgre Valley lands have 

 yielded the most astonishing returns. Tributary to the 

 city of Montrose are 2,000 acres of bearing orchards, the 

 annual income from which averages $300 per acre. Fruit 

 in some instances has commanded the remarkable sum of 

 $1,000 per acre, being sold on the trees and representing 

 (Continued on page 383.) 



