26 
BULLETIN 304, U. S. DEPARTMENT OF AGRICULTURE. 
approximate capacity of 30 cubic feet per second and one 12-inch 
centrifugal pump with a capacity of 8.5 cubic feet per second. The 
combined capacity in depth per 24 hours is now 0.28 inch over a 
watershed of 3,200 acres. Previous to January, 1912, only the 26- 
inch pump had been installed. Up to that time only a rough daily 
memorandum had been kept of the operation of the plant. How- 
ever, some estimates were possible for pumpmg done during that time. 
In 1909 this plant started on March 10 and operated intermittently 
as required until July 25, during which time the district was drained 
satisfactorily. The total time of operation was forty-five and seven- 
tenths 24-hour days, making the total depth of water removed 10 
inches. During this period the most severe test of the capacity of 
the plant was 4 days of steady operation, July 7-10, followed by 7 
hours on July 11, or a continuous run of 103 hours. This was caused 
by a heavy rain on July 5, 6, and 7, totaling 4.1 inches. The amount 
pumped was approximately a depthof 0.96 inch from the whole district. 
In October, 1909, the pump drive was changed from gas engine to 
electricity; from that time until June 20, 1910, a total of 1,365 hours 
were run, equivalent to 56.9 days. The total depth pumped during 
this period was approximately 12.7 inches. During this period the 
plant was never run more than 12 hours in one day, and very seldom 
as much as this. As will be shown later, the year 1909, although not 
an extreme one, was rather wetter than the average, while 1910 was 
remarkably dry. 
After January, 1912, an accurate daily record of the pumping was 
kept, and from these records the daily amount pumped has been 
calculated. While the capacity given for the large pump is only 
approximately correct, most of the pumping was done with the small 
pump, which had been carefully rated. In Table 3 is given a state- 
ment of the daily rainfall and amounts pumped for the largest storm 
periods in 1912 and 1913. The year 1914 was unusually dry and no 
storm of consequence occurred during the entire year. 
Table S.- 
-Daily rainfall and run-off, 
Pekin-La Marsh Levee and Drainaae 
District, 
1912 and 1913. 
Day. 
Rainfall. 
Run-off. 
Day. 
Rainfall. 
Run-off. 
Day. 
Rainfall. 
Run-off. 
1912. 
Incites. 
Inches. 
1912. 
Inches. 
Inches. 
1913. 
Indie*. 
Inches. 
Apr. 26 
0.54 
0.05 
June 10 
0.00 
0.03 
Mar. 19 
0.00 
0.06 
27 
.00 
.08 
11 
.00 
.03 
20 
.15 
.06 
28 
1.08 
.12 
12 
.22 
.03 
21 
1.22 
.10 
29 
.42 
.14 
13 
.14 
.03 
22 
.00 
.11 
30 
.00 
.14 
14 
.05 
.02 
23 
.9s 
.12 
May 1 
.22 
.13 
15 
2.10 
.03 
24 
. 25 
.13 
2 
.74 
.15 
16 
.03 
.13 
25 
.08 
.18 
3 
.00 
.23 
17 
.00 
.14 
26 
.00 
.17 
4 
.00 
.16 
18 
.oo- 
.08 
27 
.00 
.10 
5 
.40 
.13 
19 
.37 
.05 
28 
.00 
.10 
6 
.00 
.12 
20 
.20 
.04 
7 
.00 
.09 
21 
22 
23 
Total.. 
.00 
.00 
.00 
.06 
.01 
.03 
Total. . 
Total. . 
3.40 
1.54 
3.11 
.74 
2. 68 
1.13 
