20 BULLETIN 193, TJ. S. DEPARTMENT OF AGEICULTTJKE. 



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 directly 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 will 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 River, 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 with the specified 

 dimensions; therefore it wiU be possible to use many of the levees as 

 roadways when they are properly settled and smoothed. 



■CONSTRUCTION. 



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. 



