TESTS OF DRAINAGE PUMPING PLANTS. 
29 
TEST OF PUMPING PLANT IN SUBDISTRICT NO. 4, JEFFERSON DRAINAGE DISTRICT 
NO. 4, JEFFERSON PARISH, LA. 
DESCRIPTION" OF PLANT. 
In Plate I are shown interior and exterior views of this plant, and 
figure 3 is a cross-sectional view showing the shape of the suc- 
tion and discharge pipes and method of supporting the plant. 
The pumping equipment consists of two duplicate units, each with 
a capacity of 59 cubic feet per second at a 2-foot lift and capable of 
pumping at any head between zero and 10 feet, the capacity decreas- 
ing as the head increases. The pumps are 30-inch, double-suction, 
slow-speed drainage centrifugals with special radial and axial flow 
impellers having a nearly constant horsepower input at all heads. 
They are direct-connected through friction-clutch couplings to 
60-horsepower distillate engines designed to make 190 revolutions 
per minute and operating on cheap distillate of 39° Baume gravity. 
Fig. 3.— Elevation of pumping, subdistrict No. 4, Jefferson drainage district No. 4. 
The engines are started on gasoline, run for a few minutes until the 
jackets warm up, and are then switched to distillate by throwing 
the handle of a six-way cock. Batteries are unnecessary, as the 
engines are fitted with oscillating magnetos suitable for starting as 
well as running, a valuable feature for an isolated plant. Cooling 
water is supplied by two rotary pumps belted off the hub of the 
clutch coupling, one to each unit. Each of these pumps is of ample 
size to supply water to both main engines and to the water-sealed 
glands of the main pumps. To insure a supply of water for starting 
and to provide against accidents to the circulating pumps, a 500- 
gallon elevated tank was erected. This furnished an hour's supply 
for one engine and is so piped that should the pump stop working, 
water would still flow to the jackets. An added advantage of this 
arrangement is that it gives a constant head of water on the jackat 
at all times. 
