THE IRRIGATION AGE. 



155 



During the construction of the sump, adverse 

 subsoil conditions were encountered which no doubt 

 increased the cost of the sump by several hundred 

 dollars over what it would have cost if located else- 

 where. It is probably also true, although as yet not 

 conclusively proven, that equal efficiency could have 

 been obtained by spacing the laterals about 400 feet 

 apart, instead of 315 feet, thus eliminat- 

 ing one on each side of the main drain. 

 This last change could certainly have 

 been made had the laterals been placed 

 eight inches to one foot deeper. These 

 duplicate and apparently unnecessary 

 expenditures were caused in the first 

 instance, because it was found that the 

 measured drainage discharge for this 

 tract is more than double that usually 

 found in irrigated sections, and in the 

 second instance, by the experimental 

 nature of the undertaking. 

 Operations and Expenses During 1915 



Immediately after flooding opera- 

 tions were discontinued in 1914 a rank 

 growth of Bermuda grass sprang up 

 over the tract, replacing the growth of 

 alkali weeds which were so abundant 

 in 1913. It is probable that some of the 

 seed of this grass was brought to the 

 field by the water used in flooding and 

 also there seems to be little doubt but 

 that much of it was dormant in the soil 

 and started to grow as soon as growing 

 conditions were improved. It now be- 

 came apparent that before successful 

 crops of alfalfa could be grown the 

 Bermuda grass must be eradicated and, 

 consequently, after the second flooding, 

 which took place in April, 1915, and 

 covered practically the same area as 

 was flooded -the previous year, the en- 

 tire season was spent in attempting to 

 control this grass. The tract was 

 plowed to a shallow depth several 

 times, so as to expose the roots to the 

 hot sun. The loosened grass was 

 raked together and burned. The end 

 of the season showed a very marked reduction in 

 the amount of Bermuda grass present. During the 

 year 1915 the following expenses were incurred : 



Item Total Per acre 



Maintenance and repairs to drain 



and pump $70.64 



Repairs to irrigation system. . . . 95.50 

 Pumping costs (power, etc.). . . . 278.15 



Flooding ' 149.38 



Control of Bermuda grass . . 1,843.48 



PUMPING AND FLOODING 

 Pumping and Flooding 



Beginning February 23, 1914, and continuing 

 until May 1, the tract was being flooded. Within a 

 week after flooding began, ten acres or more were 

 under water, but the first pump which was installed 



jxa.fi. 



-ti- 



MAY 



JULY 



AUG. 



SEP. 



$2,447.15 $16.20 



Total for project, January, 1916. $15,219.38 $100.78 

 The expenditures shown in this report do not 

 include planting or harvesting the corn in 1914, nor 

 the hay in 1916, nor water taxes for three years ; 

 neither do they include rebate on the tile replaced, 

 main pump and motor replaced or the auxiliary 

 pump. 



Fig. 1 Curves showing ground water table on Kearney Vineyard Experi- 

 ment Drain. 



proved too small and the ground water rose rapidly 

 during the flooding. The flooding was then discon- 

 tinued until after the auxiliary pump was installed. 

 During the flooding as much land was kept under 

 water as possible, so that the alkali would be carried 

 downward rather than laterally. As much as forty 

 acres were under water at one time. No estimates 

 were obtained showing the amount of water used 

 in flooding, except that the area flooded was kept 

 under water from six inches to twelve inches deep 

 for a period of at least one week. Measurements 

 taken of the pump discharge show that there were 

 approximately 97,580,000 gallons, or 300 acre-feet 

 removed from the tract during the year. This is 

 sufficient water to cover the entire 160 acres 1.88 

 feet deep. This does not include any discharge from 

 the auxiliary pump. 



Due to the flooding and the lack of proper 

 pumping equipment, the ground water remained 



$0.47 

 0.63 

 1.90 

 0.99 



12.21 



