56 BULLETIN 1017, U. S. DEPARTMENT OF AGRICULTURE. ■ 



The Red River watershed includes large areas of land that origi- 

 nally were sloughs, marshes, and swamps. These are of two classes 

 with respect to location and origin of swampy condition; namely, 

 those lying near the Red River in the bed of the glacial Lake Agassiz, 

 and those outside the old beaches and situated at a considerably 

 higher elevation. The former owe their existence as marsh land 

 to the spreading of the larger streams as they came from the higher 

 ground into the flat lake bed, and to small creeks, blind coulees, and 

 general surface flow on to the almost level land bordering the river. 

 These swamp areas lie on both sides of the Red River for the greater 

 part of its length and generally are free from timber. The second- 

 named type of swamp results from insufficient outlet due to flatness 

 and to natural barriers to stream flow in the form of ridges. Most 

 swamps of this class lie in the eastern part of the watershed. Some 

 the low pockets entirely surrounded by higher land, but for the most 

 part they are swamps of comparative^ wide extent and are perma- 

 nently saturated. Direct precipitation, surface flow, and small streams 

 constitute the source of their water. L/ying as they do in the upper 

 part qf the watershed, no large streams traverse them as in the case of 

 those in the lower levels. In fact, most of the larger streams which 

 contribute to the swampy conditions below have their sources in 

 these upper areas. These swamps, for the most part, originally 

 were timbered, although in places there were considerable areas of 

 open country and more has been cleared as drainage activities have 

 progressed. 



DKAINAGE DITCHES. 



In studying the artificial drainage of the watershed the flat areas 

 which form the old lake bed were considered separately from the 

 upland areas. The lands included in the former class are those lying 

 on both sides of the river inside the 1,050-foot contour (see fig. 1) 

 from Lake Traverse to the north line of Richland and Wilkin Coun- 

 ties; inside the 1,000-foot contour from there to an east- west line 

 through Fargo ; inside the 950-foot contour from Fargo to an east- 

 west line through Grand Forks; and inside the 900-foot contour 

 from there to the Canadian boundary. The drains which serve 

 these lowlands have but little fall and lie only slightly higher than 

 the Bois de Sioux and Red Rivers which they enter either directly or 

 through short reaches of natural streams. Consequently, they de- 

 pend to a large extent for efficiency upon the conditions of river 

 flow and are intimately connected with any project concerning the 

 river. The upland systems, with greater fall and free-flowing out- 

 lets, are not directly concerned with the conditions below. 



The wet lands along the main watercourse have been improved by 



. enlarging and extending the channels of the larger streams, and by 



systems of open ditches. The most extensive work of this nature 



