WET LANDS OF SOUTHERN LOUISIANA. 



33 



lias been made harder because the land near the railroad is from 1 to 2 feet 

 lower than that near the lateral canal. As a result the ditches have had to be 

 5 feet deep near the lateral canal in order to give a scant 2 feel of draipage 

 near the railroad. While the surface of most all the prairie lands is nearly flat, 

 it is best to take advantage of the natural slopes in laying out the field ditches. 

 Ditching operations were started in 1911 and continued through the following 

 years as the land was desired for cultivation. All of the land between the main 

 reservoir canal and the railroad had been drained in 1915 with ditches spaced 

 210 feet apart, and the land on the other side of the main canal had been par- 

 tially drained with ditches spaced about S40 feet apart. As soon as this land is 

 needed for cultivation it will be ditched completely. 



Pumping Plant. 



The pumping plant is located about 300 feet back from the bayou front, on a 

 leveed outfall canal. This location was selected that advantage might be taken 



Pig. 8. — Sketch plan and elevation of one unit in pumping plant on Des Allemands 



Drainage District. 



of a firm ridge of silt as a foundation for the machinery. The arrangement and 

 character of the foundation are shown in figure 8. There are two duplicate 

 units, each consisting of a 24-ihch, cast-iron, double-suction, horizontal, centrifu- 

 gal pump, direct connected by means of a flexible coupling to a 12 by 12 inch, ver- 

 tical, slide-valve steam engine. The suction and discharge pipes are tapered their 

 entire length, so that the area of the end of the intake is four and one-half times 

 and the area of the discharge pipe three times that of the discharge opening on the 

 pump. This enlargement of the pipes probably reduces the friction and velocity 

 head losses to less than 0.5 foot, while if they were not enlarged the losses would 

 amount to nearly 4 feet. These pumps operate efficiently, as everything within 

 reason has been done to cut out unnecessary losses. Steam is furnished by two 

 Scotch marine boilers, burning fuel oil. This type of plant is reliable and easily 

 operated, but uses considerably more fuel oil than does the best type of steam 

 engine or an internal-combustion engine. Both units have been run for periods 

 of four or five days without stopping. 

 30444°— Bull. 652—18 5 



