DRAINAGE OF WET LANDS OF SOUTHERN LOUISIANA. 



45 



of 4 or 5 clays and were in good condition at the end of the run. This type 

 of plant seems to give the reliability that is necessary in a drainage plant. Its 

 theoretical capacity when operating at full load is 0.95 inch of depth in 24 hours. 



AREA NO. 6, NEAR POYDRAS, ST. BERNARD PARISH, LA. 



This district is part of a tract of 85.000 acres of land that lies to the south 

 of the little town of Poydras, in St. Bernard Parish, being about 15 miles from 

 New Orleans. The front boundary of the tract is for the most part the back 

 line of the river-front plantations and the land extends back several miles. 

 Most of the area is open grass-covered prairie, with only a narrow belt of 

 timber near the front line. As a whole it is almost at mean tide level, the 

 average elevation being not far from 0.5 foot. The muck is close to 4 feet 

 deep and is not quite so turfy in character as is that in the vicinity of Race- 



Fig. 13. — Sketch plan and elevation of one unit in pumping plant on area No. 5, Des Alle- 



mands, La. 



land and Lockport. It seems to be the result of the decay of the usual growth 

 of prairie grass, but has considerable silt mixed in with the decayed vegetable 

 matter and lies on a subsoil of typical Mississippi River silt, of chocolate- 

 brown color. Owing to the slight elevation of the land it is quite soft, since it 

 has never had a chance to drain and become solid. The front part is not cut 

 up to any extent by bayous, although the tract includes a lake with an area 

 of nearly 5 square miles. 



The greatest problem to be solved in the reclamation of this tract is the pro- 

 tection against storm tides. The maximum rise in tide at this point is between 

 5 and 6 feet. This is higher than any on record for a period of about 100 years 

 previous to the storm of September, 1909, which. gave this maximum height. 



Area No. 6 contains 2,000 acres of open grass-covered prairie taken from the 

 above-described tract of land and in addition contains 500 acres of a river- 

 front plantation. It is so located that an addition to it can be made on the 

 west side if the pumping plant proves larger than necessary. 



