60 BULLETIN 1017, U. S. DEPARTMENT OF AGRICULTURE. 
trol and extending across the watercourse and the adjacent lowland 
near White Bock, S. Dak., and also an earth levee at the south end of 
the lake, near Browns Valley, Minn. 
2. A new channel for the Bois de Sioux from the clam in Lake 
Traverse to a point near Wahpeton, N. Dak., where the natural chan- 
nel will carry the water without flooding. 
3. A system of ditches to provide for the drainage in the areas to 
be reclaimed by the project. 
In addition it will be necessary to replace some of the present 
bridges with larger ones and to construct new ones at points where 
the operations would otherwise interfere with transportation. 
These improvements are designed to relieve flood conditions, make 
possible the reclamation of the wet lands along the Bois de Sioux, 
and provide outlets for the drainage necessary to the development 
of this area. 
DESCRIPTION OF WATERSHED. 
Lake Traverse and the Bois de Sioux Biver, with their tributary 
watershed, include the south end of the bed of the glacial Lake 
Agassiz and the land adjacent to its shores. The nature of the topog- 
raphy and soil is a result of glacial action and subsequent natural 
processes as previously discussed. The soil is alluvium, composed of 
clay mixed with varying quantities of fine sand and organic matter, 
with occasional bowlders occurring in the vicinity of White Bock. It 
is fertile, and when drained and cultivated produces good crops of 
wheat and other small grains, potatoes, grasses, and vegetables and 
fruits adapted to the climate. 
That part of the watershed lying in North and South Dakota, to- 
gether with a strip approximately 30 miles wide just east of the 
Bois de Sioux and Lake Traverse in Minnesota, is prairie land. 
The only timber occurs in strips, varying in width from 100 feet to 
one-half mile, along the principal streams. The land is flat and rises 
in a gentle slope on both sides. Practically all the prarie land has 
been cultivated. 
The eastern. portion of the watershed, in Minnesota, was originally 
covered by forests. The topography is quite rough and there are 
many depressions, in some of which are found lakes while others are 
simply marshes. Over much of the area the timber has been cut and 
the lands cleared, until at present probably less than 10 per cent of 
this area is forested. The total area of the watershed above the 
junction of the Bois de Sioux with the Otter Tail, at Breckenridge, 
Minn., is 1,875 square miles. 
Owing to the flatness of the land surface and to the limited quanti- 
ties of water which the drainage channels have carried, the latter are 
poorly developed and are not large enough to carry off the excess of 
