Geological Papers. 85 



flow have not varied perceptibly in the period of time that 

 the writer has known western Kansas, which is nearly thirty 

 years. Thus it is well established that the underflow is not 

 dependent on the rainfall in that section of the state. Another 

 proof of that fact, if another were needed, is that creeks and 

 ponds dependent on surface water, or that coming from local 

 rainfall, are dry most of the time. The underflow varies but 

 slightly in wet and dry years, and often the variation is con- 

 trary to would be expected. 



In eastern Kansas the ground-water table is a different 

 proposition. The water that falls on the surface and does not 

 run off in the streams or is not used up immediately by vege- 

 tation percolates through the ground and settles down to a 

 certain level known as the ground-water table, or the top of 

 the permanent water supply. In general, this table is marked 

 by the top of the water in the streams in any part of the state. 

 The location of the table in any particular locality depends 

 on the condition of the aquifer. Also, the underlying and over- 

 lying rocks being pervious or impervious influence the amount 

 of water received by the aquifer as well as the retention of the 

 same. 



To say that the ground-water table has been lowered four 

 feet, or six feet, or eight feet, does not refer to any particular 

 locality, but means that the area comprising the eastern half 

 of Kansas taken as a whole has had the ground-water depleted 

 until it has sunk somewhere in that range. In the vicinity of 

 Baldwin some creeks are dry that had pools as deep as eight 

 feet, while in others the water maintains its level at about 

 five feet below the former level. On the other hand, the 

 writer knows of one well of living water that lowered nearly 

 twelve feet, and several others that were lowered from five to 

 eight feet. Nor is this locality very different from those all 

 over this part of the state. From reports gathered from this 

 entire end of the state the writer estimates that since 1901 

 the water table has been lowered an average of five or six 

 feet. And what makes the condition all the more serious, in 

 many places several feet of dry earth intervene between the 

 water table and the surface water from the late fall rains. 

 The amount of rainfall necessary to thoroughly soak the ground 

 all the way down to the ground-water table is very problemati- 

 cal. However, this is one of the conditions to be met before 

 the raising of the table begins. 



