WELLS OF CARROLL COUNTY, ILLINOIS. (51 1 



The last edition of the Manual of American Waterworks (1897 ) reports 

 that the village of Pawpaw, in the southeast part of the county, obtains its 

 public supply from an artesian well 1,018 feet in depth. 



CARROLL COUNTY. 



GENERAL STATEMENT. 



Carroll County borders the Mississippi River in the second tier of 

 counties from the north and has an area of 440 square miles, with Mount 

 Carroll as the county seat. The northwestern portion is drained by Plum 

 River and Carroll Creek, its main tributary, directly to the Mississippi 

 Valley at Savanna. The southeastern portion is drained southward 

 through Rock and Elkhorn creeks into Rock River. The surface is rolling 

 and drainage good throughout the upland portion of the county. 



With the exception of the northwest corner, which is unglaciated, this 

 county is covered with a sheet of drift of moderate depth. Records of 14 

 wells on the uplands, distributed widely over the county, show an average 

 of 54 feet to the rock, the greatest depth being about 100 feet. In the 

 Mississippi Valley below Savanna there is probably 150 feet or more of 

 drift, as indicated by borings at Sabula, Iowa, and Fulton, Illinois, which 

 reach a level nearly 150 feet below the Mississippi before entering rock. 

 The valley drift is largely sand or fine gravel. The drift on the uplands is 

 in places a gravelly or stony material, but usually has a large clay admix- 

 ture, such as characterizes the typical till. 



In every township of the uplands numerous wells enter the rock, but 

 a still larger number obtain water from gravel or sand associated with till 

 at various depths from 20 feet or less up to about 100 feet. 



INDIVIDUAL WELLS. 



At Savanna the public water supply is from an artesian well 1,430 

 feet in depth, which terminates in the Potsdam sandstone. It discharges at 

 the rate of 500 gallons per minute and has a pressure of 35 pounds per 

 square inch at the level of the well mouth, about 600 feet above tide. The 

 head is, therefore, about 675 feet. 



At Mount Carroll the public water supply is from a well 2,502 fee; 

 in depth, which has a head sufficient to rise nearly to the well mouth, 

 about 700 feet above tide. Water was struck in the limestone at 65 to 100 



