e 
12 BULLETIN 1098, U. S. DEPARTMENT OF AGRICULTURE. 
growth was removed first, piled along the banks, and burned when 
sufficiently dry. The trees, logs, and stumps were then removed and 
placed upon the banks in suitable lengths for hauling away for use 
as firewood. In many instances the roots of the larger trees and old 
snags could not be removed without an amount of effort which would 
have added greatly to the cost of the work. These were sawed off 
even with the bed of the bayou and allowed to remain. They might 
have been removed rather cheaply by the use of dynamite, had the 
facilities for that work been available. The photographs repre- 
sented by Plate ITI, Figure 3; Plate IV; and Plate V, Figure 1, give 
a very good idea of the extent and nature cf the work that was done. 
The appearance of the stream during the operation of clearing is 
shown in Plate V, Figures 2 and 3. 
CONSTRUCTION OF THE DAM. 
In making the fill, or cross levee, for the dam, advantage was 
taken of a shallow point in the bed of the bayou used as a low- 
water crossing by the tenants. The banks at this point were favor- 
able—that is, high enough on either side to allow the water to 
be raised to the required level. The required height of water was 
gained by running levels along the banks above the site of the dam. 
The dam was constructed to give a depth of 4 feet 10 inches at the 
floor of the spillway. When one recalls that the fall in the bed of 
the bayou in this section averages only 0.6 foot to the mile, it is 
seen that the level at the dam was carried back over the course of 
the stream for a considerable distance with only a slight variation 
in depth. The impounding was effective for depth about $ mile 
above the zone included in the survey, with the exception of a ridge 
which crosses the bed of the bayou just above the last station. 
The details of the fill and spillway for the dam are shown in 
Figure 2 and in Plate VI, Figures 1 and 2. The completed dam, 
with bridge over the spillway, providing a roadway to the section 
of the plantation lying on the opposite side of the bayou, is shown 
in Plate VI, Figure 3. The labor and material involved in clearing 
the bayou and in the construction of the fill and spillway for the 
dam, are shown in Table 6. The bill of lumber for the spillway is 
shown in Figure 2. 
TABLE 6.—Cost of clearing a section of Bayou Walnut and impounding water 
in same, 19158. 
Preliminary survey, running levels, plan and specifications of spillway__ $45.00 
Clearing undergrowth and grass from bed and edges of bayou, includ- 
ing piling and burning: 
19 men, 6:daysat pldoe a a ee ee coe 
® MEN... Cav sy Ae ke ee ere ee 15. 00 
127. 50 
