LAND DRAINAGE BY MEANS OF PUMPS. 



27 



It will be noted that the storms occurring in the early spring, when 

 the ground is wet and the evaporation is small, have a much larger 

 percentage of run-off than those occurring in summer. The monthly 

 rainfall and run-off for the above district for the years 1912, 1913, 

 and 1914 are given in Table 4. 



Table 4. — Monthly rainfall and run-off, Pekin-La Marsh Levee and Drainage District. 



Month. 



1912 



1913 



1914 



Rainfall. 



Run-off. 



Rainfall. 



Run-off. 



Rainfall. 



Run-off. 





Inches. 

 0.00 

 1.17 

 1.68 

 5.50 

 4.40 

 4.42 

 4.07 

 2.16 

 4.40 

 4.09 

 1.76 

 .81 



Inches. 



0.71 



.58 



1.71 



2.61 



2.61 



1.24 



.79 



.29 



.27 



.68 



1.28 



.64 



Inches. 

 1.94 

 2.48 

 3.07 

 2.86 

 1.82 

 1.59 

 1.27 

 2.74 

 2.30 

 2.52 

 2.25 

 1.21 



Inches. 



1.04 



1.18 



2.85 



14.18 



1.19 



.65 



.19 



.00 



.00 



.10 



.17 



.26 



Inches. 

 1.61 

 1.61 

 1.01 

 2.03 

 1.90 

 1.56 

 1.44 

 1.95 

 5.09 

 2.10 

 .14 

 .41 



Inches. 

 0.30 





.36 





1.34 





1.32 





.83 





.17 



July.... 



.02 





.00 





.18 





.21 



November 



.09 

 .06 







Total 



34.46 



13.41 



26.05 



11.81 



20.85 



4.88 







i Large run-off due to flow of water through pump from river during high stage. 



The East Peoria Levee and Drainage District, on the Illinois River 

 opposite Peoria, 111., has been pumping since 1911. The plant is 

 equipped with one 15-inch and one 18-inch centrifugal pump. The 

 combined capacity of the pumps is 33.5 cubic feet per second, or a 

 depth of 0.51 inch from the entire watershed of 1,550 acres per 24 

 hours. Accurate records were obtainable only for the period from 

 September 15, 1913, to September 15, 1914. The weather was very 

 dry and no period of pumping occurred which taxed the pumping 

 plant seriously. The monthly totals of rainfall and run-off are given 

 in Table 5. 



Table 5 



— Monthly 



rainfall and run-off, 



East Peoria Levee and Drainage District. 





1913. 



1914. 



Total. 





Sept. 



Oct. 



Nov. 



Dec. 



Jan. 



Feb. 



Mar. 



Apr. 



May. 



June. 



July. 



Aug. 



Sept. 



Rainfall 



Run-oS 



In. 



2.38 



.04 



In. 



2.81 



.19 



In. 



2.77 

 .33 



In. 



0.73 



.38 



In. 

 0.21 



. 65 



In. 

 1.36 

 .60 



In. 

 1.60 

 1.06 



In. 

 2.10 

 1.34 



In. 

 2.29 



1.10 



In. 

 1.95 



.64 



In. 



0.85 



.35 



In. 



2.40 



.19 



In. 



3.90 



.13 



In. 

 25.35 

 7.00 



The largest amount pumped on any one day during the above 

 period was a depth of 0.1 inch on April 7, the first day after a rain of 

 0.95 inch. The data from this district for 1914 are of no value in the 

 genera] determination of necessary capacity, but they will bo used 

 later in connection with the cost of pumping. 



The Ijouisu-Dos Moines Drainage District No. 4, about 20 miles 

 north of Burlington, Iowa, on the Mississippi River, has been pump- 

 ing since 1000. This district has a watershed area of 1(5,000 acres 



