PREFACE 



Since the end of World War II there has been a rather 

 sharp divergence in published opinions regarding the na- 

 tional ground-water situation. The use of ground water in 

 agriculture and industry increased greatly during the War. 

 By 1945 this use had become about twice what it had been 

 ten years before. 



In 1 948 The Conservation Foundation discussed this diver- 

 sity of opinion with several ground-water authorities, who 

 confirmed the need for analysis on a national scale of the de- 

 tailed information collected from various parts of the coun- 

 try. A committee, composed of Dr. Abel Wolman of The 

 Johns Hopkins University, Edward N. Munns of the U.S. 

 Forest Service, Carl G. Paulsen and Dr. A. Nelson Sayre of 

 the U.S. Geological Survey, and Homer Wells of the U.S. Soil 

 Conservation Service, agreed to advise the Foundation in a 

 project to summarize the national situation on the basis of 

 the detailed information available. This volume is the report 

 of that project, which was undertaken by the author during 

 the year beginning July 1949. It is based upon published re- 

 ports, unpublished data, and discussions with technical men 

 in various Federal, state, and private agencies studying prob- 

 lems pertaining to ground water. 



The author is extremely grateful for the guidance and 

 great help given him during this project by each member 

 of the Advisory Committee under the chairmanship of Dr. 

 Wolman. Their personal interest in the success of the survey 

 and their valuable criticism of the manuscript have contrib- 

 uted much to the clarity and comprehensiveness of this report. 



The descriptions and conclusions of this report are based 

 largely on the work of hydrologists and other scientists who 

 carry on research on water-resource, and particularly ground- 



