20 BULLETIN 193^ U. S. DEPARTMENT OF AGEICULTUEE. 
tect the districts in the southern part of the county against storms 
equal to those recorded at Galveston from 1888 to 1890 and from 1904 
to 1909, all levees should be at least 4 feet high, which is in accord 
with the general practice in Louisiana, and those fronting direct^ on| 
the Gulf should be at least 6 feet high. It is assumed that because 
such extraordinary storms as that of 1900 occur only at very long 
intervals, protection against loss by them wiU be by insurance rather 
than by levees of sufficient height to prevent overflow. 
The proper cross sections of levees will depend upon the material 
used and the nature of the foundation. Where the material is dense 
and the foundation firm, as along the Neches Eiver, the top width 
should be not less than 4 feet and the side slopes not steeper than 2 
horizontal to 1 vertical. On the soft marshland in the southern part 
of the county the top width of levees should be not less than 6 feet 
and the side slopes not steeper than 3 horizontal to 1 vertical. The 
material excavated from the ditches designed for the latter territory 
will be much more than enough to build levees mth the specified 
dimensions; therefore it will be possible to use many of the levees as 
roadways when they are properly settled and smoothed. 
COXSTRUCTIOX. 
In districts Nos. 6 and 7, which are covered with timber, aU stumps, 
logs, and other vegetable matter should be removed from the base of 
the levees, which should then be plowed before any material is depos- 
ited. These precautions will insure a good bond between the old and 
the new material and prevent excessive seepage. In district No. 9 
and others in the southern part of the county that are located on the 
open prairie where the ground is firm and above ordinary water level, 
a shallow ditch along the center line wiU insure a good bond. The 
berms for these levees should be at least 10 feet wide. 
On the soft marsh lands levees must be constructed with great care, 
to prevent seepage and caving. They should be built in horizontal 
layers, each layer given some time to dry before the next is added; 
this will prevent yielding of the base as the material is deposited. 
The orange-peel bucket dredge is perhaps best adapted to this work 
because it can bring suitable material from below the soft surface 
mud, and by dropping the dirt from a considerable height can compact 
it in the levee. In order to prevent excessive pressure on the ditch 
banks which might cause sloughing of the soft earth, the berms in 
these marshes should be 15 to 20 feet wide. After the levee has dried 
sufficiently it should be smoothed and brought to grade. Usually 
prairie grass will soon cover the new levee and help keep it in shape. 
Careful grazing on the levees will give some protection against bur- 
rowing animals. 
