THE RECLAMATION SERVICE 



Progress of Leading Projects -Land 

 Withdrawals Letting of Contracts 



Slioshoiie Project in Wyoming. o f j ts two ma i n forks the ShosllOtie 



f~\ N the main thoroughfare leading River enters a very narrow canyon, 

 into the Yellowstone National four miles in length, one mile of which 

 Park from the east, in a region of wild is in solid granite walls rising nearly 

 and wonderful topography, the Gov- perpendicular several hundred feet, 

 eminent engineers are engaged upon At the point selected for the dam the 

 an irrigation project which is destined canyon is 65 feet wide at the bottom, 

 to convert a vast area of desert into and at an elevation of 240 feet, the 

 fertile and productive farms. The height of the proposed dam, 180 feet 

 main area of land to be irrigated is wide. The reservoir created by the 

 located in the northern portion of the dam will have a storage capacity of 

 so-called Big Horn basin, on the north 580,000 acre-feet. Owing to the per- 

 sicle of Shoshone River, seventy-five pendicular canyon walls, it will be nee- 

 miles east of the Yellowstone Park. essary to design a tunnel to provide 

 Field investigations and surveys for the discharge of a wasteway for 

 were begun on this project in May, excess floods to pass the dam. 

 1903, and have been carried on since This tunnel will be constructed from 

 by Mr. Jeremiah Ahern, district engi- the surface of the proposed reservoir 

 neer. The reclaimable area is approx- through the solid granite of the moun- 

 imately 200,000 acres, located on both tain, and will discharge the water into 

 sides of the Shoshone River below the the river several hundred feet below 

 canyon. The land is of general good the dam. The capacity of the tunnel 

 quality and, as shown by large areas will be 25,000 cubic feet per second, 

 already under cultivation in the imme- ample to carry the largest floods of the 

 diate vicinity, will be highly produc- stream. The outlet works will have a 

 tive when irrigated. The Shoshone capacity of 2,500 cubic feet per second, 

 River, which furnishes the water sup- the discharge being through a tunnel 

 ply, has a drainage area of 1,250 excavated in the solid granite walls of 

 square miles extending into the moun- the mountain at an elevation of 60 feet 

 tains to an elevation of over 12,000 above the stream bed. The tunnel will 

 feet. Measurements and gagings of be 14 feet square, discharging under 

 the river have been maintained since pressure, and will be controlled by a 

 1892, and show a mean annual run-off series of gates at the intake end. As 

 of about 1,000,000 acre-feet, with originally designed, 150,000 acres on 

 maximum floods reaching up to 15,000 the north side are to be supplied 

 cubic feet per second or more in the through a simple high line conduit 

 early summer, and running down to having a total length of about 75 miles, 

 250 cubic feet per second or less dur- decreasing in carrying capacity as dis- 

 ing the winter. The great variation tributory canals are taken out. 

 between the maximum and minimum The first three and a half miles of 

 flow necessitates impounding the flood the main canal will be through the 

 run -off to secure a regulated supply canyon and mostly in tunnel, the re- 

 -for the irrigation of large areas. An maining distance by canal, which at 

 excellent storage reservoir site has the head will be 60 feet wide on the 

 IK vii found on the main stream at bottom with water eight feet in depth. 

 some distance above the land to be Diamond drill borings were begun at 

 irrigated, the dam site being in a gran- the dam site in August, 1903, to deter- 

 ite canyon. Just below the junction mine bed rock conditions, depth, etc. 



