Nov. 5, 1917 
Run-off from Drained Prairie Lands 
249 
capacity was increased to 0.50 inch by further dredging. Except for a 
few short periods the entire area was well drained during the time cov¬ 
ered by the records. During the early part of the period covered by 
the records the levees on this district were subject to a heavy seepage 
when the stage of the water was high on the outside. Later the levees 
were increased in size and the seepage was reduced greatly. 
Conditions during 1909. —During this year about 25 per cent of 
the area was in cultivation. The remainder was covered with grass 
and weeds. The portion of the land cultivated was well drained through¬ 
out the year. Some of the lowest land near the reservoir was flooded 
for a short time during the heavy rainfall of September 20, but this 
was due to the fact that the tropical hurricane which accompanied the 
rainfall interfered with the proper operation of the machinery. 
Conditions during 1910.—About 65 per cent of the land was cul¬ 
tivated, and the entire area was well drained. The year was deficient 
in total rainfall and in heavy storms. The early part of the year was 
exceptionally dry. 
Conditions during 1911.—The cultivated area was increased to 75 
per cent and drainage was maintained. Some quite heavy rainfalls 
occurred. Toward the end of the year fairly heavy rainfall coming at a 
time of low evaporation raised the water outside the district so that 
very heavy seepage came through the levees. The records for Decem¬ 
ber (Table I) do not represent normal relations as between rainfall and 
amount pumped; they were not included in obtaining averages for the 
period. 
Conditions during 1912.—The cultivated area amounted to 85 per 
cent. A continuation during January of the high stage of water outside 
the district caused the amount of water pumped to be greatly above 
normal, and a recurrence of this stage of outside water in June and July, 
and again in December, caused the pumping for the year to be excessive. 
The averages for the tract exclude the above months. 
Conditions during 1913.—During this year the entire tract was 
brought under cultivation for the first time. The water level in the 
main canal was held unusually low, and drainage was complete at all 
times, with no flooding. During the year nearly the entire length of 
levee received further addition of material, and its ability to keep out 
seepage water was thereby much increased. It does not appear from the 
records that any great amount of seepage water entered the district 
except during the first part of January. Although the run-off during 
the month of October was greater than the rainfall, most of the rainfall 
came the last few days of September and was not pumped during the 
same month. By taking the two months together the percentage of 
rainfall in the run-off is about 75 per cent—not an excessive amount for 
such heavy rainfall at that time of year. 
