760 THE ILLINOIS GLACIAL LOBE. 



At Centralis! wells obtain water at 14 to 30 feet from clay or gravel. 

 The public supply is from impounded water. 



CLINTON COUNTY. 

 GENERAL STATEMENT. 



Clinton County is situated west of Marion County, in the southwestern 

 part of the State, with Carlyle as the county seat, and has. an area of 494 

 square miles. The Kaskaskia River leads southward through the eastern 

 part of the county and there turns westward, forming the south boundary. 

 Shoal Creek, its largest tributary, traverses the west-central part of the 

 county and enters the Kaskaskia about 8 miles from the west border of the 

 county. Crooked Creek, an eastern tributary, forms a part of the south 

 boundary of the county. The streams have channels sunk but a few feet 

 below the level of the bordering plains and drainage lines are not well 

 developed. The compact white clay which covers the county absorbs the 

 rainfall slowly, thus leaving much of it to be disposed of by evaporation. 



Occasional drift ridges and knolls break the monotony of the plain. 

 The highest reach elevations of 50 to 75 feet or more above the plain, and 

 the majority have a height of fully 30 feet. The best developed system of 

 ridges appears along the Kaskaskia River, east and southeast of Carlyle. 

 There is a nearly continuous chain of knolls about 5 miles in length, which 

 crosses the Baltimore and Ohio Railway in north to south direction about 

 3 miles east of Carlyle. These knolls and ridges connect on the north 

 with those in Bond and Fayette counties already discussed. 



The thickness of the drift in this county seldom exceeds 50 feet, and 

 not a few wells enter rock at 15 to 30 feet. A few drift sections are reported 

 in the Geology of Illinois which penetrate 70 feet of drift. In its thicker 

 portions the drift includes a hard blue till near its base, but it usually has a 

 yellow color to a depth of at least 20 feet. The wells are obtained either 

 in the sandy portions of the yellow till or at slight depth in the underlying 

 rock. The blue till is apparently very compact and a poor medium for 

 supplying water. 



INDIVIDUAL WELLS. 



At Carlyle wells are usually obtained at about 25 feet without entering 

 rock. The waterworks are supplied from the Kaskaskia River. 



