WET LANDS OF SOUTHERN LOUISIANA. 



25 



on this district could be made of the same 

 length. On the back lands, however, the 

 ditches already are about as long as would 

 be advisable, since the land is almost level. 

 At present these ditches are too shallow 

 to give adequate drainage. Some measure- 

 ments of the depth of water table were 

 made early in the summer of 1910. The 

 results are shown graphically in figure 4. 

 It is apparent that at that time this soil 

 was not very impervious. Even after 

 heavy rains the profile of the ground water 

 was not steep. The ditches are too far 

 apart for the best results, although if they 

 were the full 3 feet deep they would drain 

 the ground much better. Now that the 

 reservoir canal is of a good depth these 

 ditches could be cut as deep as 4 feet and 

 still be pumped dry. If instead of cutting 

 new ditches between the present ones lines 

 of tile were placed midway, the purpose 

 would be served even better and consider- 

 able land would be saved. The present 

 ditches evidently are sufficient to take away 

 the surface water, and, because of the open 

 nature of the subsoil, the ground water 

 would be taken away readily. The cost of 

 maintenance alone on these extra ditches 

 would nearly pay the interest on the cost 

 of the tile work above that of the new 

 ditches ; in addition, there would be the 

 saving in land. Furthermore, if tile were 

 laid properly they would give the same 

 amount of drainage all the time, whereas 

 ditches give their best results only for the 

 first few weeks after they are cleared of 

 grass and weeds. 



Pumping Plant. 



The location of this plant is quite favor- 

 able, as it is on the lowest ground in the 

 tract and at the junction of three large 

 canals, making the distance the water must 

 travel to reach the plant about as short as 

 is practicable. 



Steam for the three following pumping 

 units is furnished by two water-tube boilers 

 and one return tubular boiler, crude oil for 

 fuel and a feed-water heater being used. 



First, a rotary chamber-wheel pump, hav- 

 ing a capacity of 40,000 gallons per minute, 

 rope driven from a 16 by 24 inch automatic, 

 noncondensing engine; second, one 42 by 16' 

 inch Menge pump, connected by a rope drive 

 and a bevel gear to a 16 by 24 inch auto- 

 matic noncondensing engine ; third, one 



30444°— Bull. 652—18 4 



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