84 BULLETIN 1017, U. S. DEPARTMENT OF AGRICULTURE. 



larger part of the channel below Grand Forks to 35 per cent just 

 below Wahpeton where the sectional area is much smaller. The 

 construction of the improvement on Red Lake and Red Lake River 

 will also have some effect in reducing flood stages below Grand Forks. 

 On account of the considerable distance the water must travel to reach 

 the river after leaving Red Lake, the effect of reducing the flow from 

 that lake will be partly lost before Grand Forks is reached. These 

 capacities indicate the rates of flow that can be accommodated 

 throughout the length of each section without overflow at any point. 



The increased capacity thus gained would not entirely eliminate 

 flooding below the mouth of the Sheyenne River. The rates of flow 

 provided for — 18,500 second-feet below the mouth of Buffalo River 

 and 30,800 second-feet below the mouth of Red Lake River — prob- 

 ably will be exceeded in the spring at intervals of from 10 to 25 years, 

 during such floods as occurred in 1882 and 1897. It is possible that 

 at still rarer intervals the summer flow may cause slight flooding, 

 but it is highly improbable that this will occur, because overflow 

 during the summer could only be caused by run-off about 40 per 

 cent greater than has ever been recorded at that time of the year. 



In all cases of flooding the river stages would, as a result of the 

 improvements, be lowered by approximately 5 feet ; this would re- 

 duce the flood damage to a point where further reduction would not 

 be economical at present. 



EESrXTS OF IMPROVEMENTS ATONG THE EED ETVEE. 



The works recommended along the Red River between "Wahpeton, 

 X. Dak., and the Canadian line consist of: (1) A floodway connect- 

 ing the Dakota Wild Rice and Sheyenne Rivers at some distance 

 above their mouths; (2) the improvement of the Sheyenne channel 

 below the floodway outlet; and (3) the clearing out of the Red River 

 channel for a distance of 394 miles from Wahpeton to the Canadian 

 boundary. The maintenance of these works when once constructed 

 is essential to the success of the project. 



The results of these improvements may be summed up as follows: 



From Wahpeton to the mouth of the Dakota Wild Rice River the 

 capacity of the Red River channel would be great enough to provide 

 for any volume of water that will come, provided the recommended 

 Lake Traverse storage reservoir is in operation ; thus overflow along 

 this section of the river would be eliminated. 



The floodway channel from the Dakota Wild Rice to the Sheyenne 

 River, functioning in conjunction with the Lake Traverse reservoir, 

 would so control the flow in the restricted section of the Red River 

 channel between the mouths of the Wild Rice and the Sheyenne 

 that it would at no time exceed the rate of 7,500 second-feet, which 

 can be carried without overflow through that section of the channel 



