ON THE IMMINITY OF THE KANSAS BOTTOM GROUND 



WATERS TO CHANGES IN THE COMPOSITION 



OF THE KANSAS RIVER WATER. 



By Prof. C. C. Young. 



THE extended period of dry weather during the three years pre- 

 vious to the series of analyses following led to a shortage of 

 ground water in the bottoms where the Lawrence Water Company 

 obtains the supply furnished the city. It was deemed advisable to 

 liave some check on the water company, so that we would be able 

 to tell when Kaw river water was used to reinforce the insufficient 

 ground-water supply. 



From time to time during the years 1909, 1910 and 1911 sufBcient 

 analyses of the Kaw and the Lawrence city supply had been made 

 so that it was certain that the ground water was very nearly con- 

 Btant in composition, while the river varied over wide limits. 



Collection of samples for comparative analyses from the Kaw 

 and city supply was commenced on January 9, 1912. The chlo- 

 rine content of the city supply at that time was 60 parts per mil- 

 lion, which is about normal for that time of year. The river 

 showed 168 parts per million. On January 10 the tap water con- 

 tained 88 parts per million and the river 142. A trip to the pump 

 house revealed the fact that the water company had the suction 

 line to the river wide open and were pumping river water. The 

 use of varying amounts of river water continued until February 9, 

 when its use was discontinued until the period from November 

 22 to December 16. 



The breaks in the chlorine content for the city water are very- 

 marked, and show readily the admixture of river water with the 

 ground supply. A simple calculation will give almost the exact 

 amount of river water that had been added at any one time. 



The statement is often made by the layman, and, I am sorry to 

 say, by some engineers, that the water pumped from the Kaw bot- 

 toms ie nothing more than river water that filters back through 

 the sand into the wells, but a study of the curve will show that the 

 composition of the ground water is affected only slightly by season 

 changes, and not at all by the composition of the Kaw. For in- 

 stance, the time between February 15 and June 1 is the highest 

 period of chlorine in the ground water and the lowest in the river. 



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