18 BULLETIN 1017, U. S. DEPARTMENT OF AGRICULTURE. 
voir for the control of run-off from the Lake Traverse watershed, 
as together they form a single interstate project for combined drain- 
age and flood prevention for that territory. The improvement of the 
Eed Eiver channel is an interstate proposition and the increase of its 
capacity is a measure for the prevention of floods. TThen proper 
provision has been made for the removal of the water that may come 
to the channel from the several States, the drainage of the land along 
its course becomes a matter of locally controlled projects, and is so 
considered in this report. 
. The Bois de Sioux-Red Eiver channel was studied in detail with 
respect to size, course, slope, and condition as to obstruction. Various 
methods of increasing the capacity were considered and conclusions 
reached as to their effectiveness and practicability. Widening and 
deepening of the channel: cut-offs: removal of brush, trees, and 
debris ; relocation of bridges : and changes in points of entry of trib- 
utary streams by means of stream diversion and artificial embank- 
ment — these were all considered in some location or other, wherever 
applicable. 
As the study of flood flow and channel capacities made it appar- 
ent that complete relief from flood conditions can not be economically 
secured through channel improvement alone, the possibility of reduc- 
ing high-water stages by means of temporary storage in the upper 
reaches of the streams was investigated. The only locations which 
seem to offer practicable opportunities in this respect are the Eed 
Lake and Lake Traverse regions. The former has been investigated 
by engineers of the TTar Department, which has reported favorably 
upon the proposed improvement. 3 An abstract of that report appears 
in another part of this report. The effect of that project upon Eed 
Eiver conditions has been considered in the present investigation. 
A thorough field study was made of the Lake Traverse region 
to determine the most advantageous location for a reservoir 
and its efficiency under extreme conditions of run-off. Storage 
capacities for various stages were computed and tentative plans were 
^prepared for the necessary controlling works. The results of such 
storage in the case of the territory immediately benefite^l. and its 
effect upon the conditions of flow in the Eed Eiver. were considered. 
The plans for recommended improvements were worked up with 
the view of securing the maximum benefits at the least cost and an 
equitable distribution of these two factors among all concerned. 
RUN-OFF. 
Eun-off is that portion of the precipitation which, falling upon a 
watershed, flows over or through the earth to a watercourse and 
c Document No. 61, House of Representatives, 66th Cong., 1st sess. 
