248 
Journal of Agricultural Research 
Vol. XI, No. 6 
of the pumps in the drainage plants has been extended along with records 
of operation of the same plants until the records now cover 10 drainage 
districts. At the end of each year progress reports have been issued 
giving the results collected. It is now proposed to summarize these 
reports in one publication. 
OBJECT OF THE INVESTIGATIONS 
The primary object of this work has been to establish the relation 
existing between the rainfall and the amount of water that it is necessary 
to pump from typical areas of land in order to secure a degree of drainage 
that will allow the growing of the ordinary field crops. When this rela¬ 
tion is once determined, the rainfall data furnished by the Weather 
Bureau will enable the engineer to design adequate and economical 
drainage pumping plants for the swamp lands of the Gulf coast. 
The records also disclose the total amount of pumping necessary in 
each year. In this paper the term “run-off ” is used to denote the water 
that is removed by the pumps; in the tables the run-off is expressed as 
a uniform depth of water (in inches) over the drained area. 
DESCRIPTION OF DISTRICTS 
The districts on which the investigations are being carried on vary in 
area from 647 acres to 7,500 acres, and the various details of soil, crops, 
surface slope, and character of the drainage channels and levees, are 
different on each district. Therefore it is believed that it will be of 
advantage to describe each district, giving a brief summary of condi¬ 
tions prevailing during each year covered by the records. 
SMITHPORT PLANTING COMPANY TRACT—AREA, 647 ACRES 
This tract adjoins the village of Lockport, Lafourche Parish. The 
land from which this plantation was reclaimed is typical of the open, 
grass-covered prairies that lie to the west of Bayou Lafourche. The 
surface slopes from the bayou to the low swamps in the rear. About half 
the area under consideration was originally covered with the water of 
Lake Fields to a depth of i to 3 feet. The humus or muck on this 
tract varied in depth from 18 inches on the higher portions to perhaps 
8 inches in the lake bed. A considerable portion of the muck in the 
higher portions of the area is overlain by a layer of river silt about 10 
inches thick. Silt of the same character forms the subsoil of the w^hole 
district. The total fall in the surface from the higher, or “front” por¬ 
tion to the lower side is about 4 feet. The ditch system is very com¬ 
plete, and the small field ditches go entirely across the area directly into 
the reservoir canal which skirts one side. The reservoir capacity up 
to the end of 1912 was 0.40 inch of water, and that of the pumping 
plant 1.10 inches, over the area drained. Thereafter the reservoir 
