26 



BULLETIN 304, U. S. DEPARTMENT OF AGEICULTUEE. 



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 pumping 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 depth of 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 3.- 



-Daily rainfall and run-off, 



Pekin-La Marsh Levee and Drainage 



District, 









1912 and 1913. 









Day. 



Rainfall. 



Run-off. 



Day. 



Rainfall. 



Run-off. 



Day. 



Rainfall. 



Run-off. 



1912. 



Inches. 



Inches. 



1912. 



Inches. 



Inches. 



1913. 



Inches. 



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 



.98 



.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 



.00 



.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 

 .04 

 .03 



Total. . 







Total. . 



3.40 



1.54 



3.11 



.74 



2.68 



1.13 



