Nov. 5, 1917 
Run-off from Drained Prairie Lands 
253 
LAFOURCHE DRAINAGE DISTRICT NO. 12, SUBDISTRICT NO. I—AREA 835 
ACRES 
This district lies about 2 miles southwest of Raceland, mostly in typical 
wet prairie land of the Lafourche section. It has a natural slope toward 
the pumping plant. The highest portion of the district is perhaps 3 
feet above mean low water in the surrounding waterways and the lowest 
portion about 2 feet. About three-fourths of the district was originally 
covered with a depth of from 1 to 2 feet of turfy humus or muck, while 
the remainder was a cypress swamp which had been burned over and 
the trees finally killed and leveled. Pumping was started about 1908 
and has since been continuous. In 1913 the inside reservoir canals were 
relocated and made larger, the levees reinforced, and the old pumping 
plant replaced by a new one. The present plant, when working at best 
economy, has a capacity sufficient to remove a depth of 1.70 inches of 
water from the entire district per 24 hours. The reservoir capacity is 
about 0.40 inch of water over the district. The district is completely 
ditched and practically all cultivated. As parts of the area have been 
cultivated for five years, the muck has been greatly compacted and is at 
present only a few inches thick; it is quite a heavy soil as compared with 
the original condition. 
Conditions during 1915.—During the early part of the year there was 
evidently considerable seepage entering the district. After the first 
three months the weather was dry, and the evaporation took up prac¬ 
tically the entire rainfall. During the month of October the district 
experienced very heavy rains, and the pumping was greatly increased 
because of seepage; therefore the records for the month are omitted from 
the averages. (See Table III.) 
NEW ORLEANS LAND COMPANY TRACT—AREA 1,255 ACRES 
This tract lies just within the northern city limits of New Orleans and 
fronts on Lake Pontchartrain. It is bordered on the west by the New 
Basin Navigation Canal and on the east by the outfall canal from the 
city pumping station 7. The water on three sides is slightly above sea 
level and is perhaps, on the ayerage, about a foot above the average 
land surface of the district. The tract was originally a part of the swamp 
that bordered Lake Pontchartrain and was covered with a rather heavy 
growth of trees, cypress being the predominating variety. This growth 
had been cut down when the record started, but only about 100 acres 
were cleared and cultivated. The remainder was allowed to grow up in 
weeds and brush. The soil is soft and spongy on the surface, with a high 
percentage of vegetable matter. The subsoil is the usual Sharkey clay 
to a depth of from 6 to 10 feet; this is underlain by almost pure sand 
which undoubtedly allows a considerable seepage into the district. The 
effect of the seepage on the run-off totals for each month is more notice¬ 
able during the winter months than at other times, especially if the 
