DRAINAGE 



figures at the government section corners, 

 giving elevations, show the very level char- 

 acter of the land. The central portion is a 

 great swamp area six by fifteen miles in 

 extent. The proposed ditch, A B, collects 

 a " lost river," which was spread out through 

 the low area into a large swamp. The 

 proposed ditches, C D, E F and G H, are 

 designed to serve as main channels to carry 



Figure 63. Surveyor's chain folded. Very desirable form 

 of chain in weeds, across streams, around curves, and for 

 general work. Often incorrect in length, and for accurate 

 work should be compared with steel tape. 



the water toward the Red River. Tributary 

 to these main ditches are roadside ditches 

 along the section lines and ditches across 

 some farms. These farm ditches are here 

 usually made broad and flat with reversible 

 road machines. Into these roadside and farm 

 ditches, dead furrows are made to lead at 

 frequent intervals, by so laying out the plow 

 lands as to place the final furrows in favor- 

 able places to lead the water off the fields 

 and into the field, roadside and main 

 ditches. In case of low places a few 

 inches to a foot below the general surface 

 and from a rod in diameter to many acres 



, t , , . t ,. , Figure 64. Sur- 



m area, they are drained by special ditches veyorj chain partly 

 into the farm ditches. It is often neces- 

 sary in late fall or in early spring to open out all drains 

 by removing weeds and dust, or earth, that has blown 



