consequence, except as it is supplementary to irrigation 

 because of the necessity of avoiding alkilinity and water- 

 logging; the problem there is chiefly one of irrigation. In 

 the North and Central Atlantic States, while there is much 

 individual farm drainage, it has not extensively come under 

 the auspices of organized enterprises. The South Atlantic, 

 East South Central, and West South Central States have 

 many areas reclaimed by organized drainage enterprises, 

 especially in West South Central States, but in these three 

 groups of States only about a third of 1 percent of all farm 

 land is drained by such enterprises. It is in the East North 

 Central and the West North Central States, especially the 

 former, that organized drainage has been developed most 

 extensively. In these two groups of States over 14 percent 

 of all farm lands is drained by collective enterprises, not 

 including the important item of individual farm drainage, 

 which reaches considerable proportions and is the dominant 

 type in some States, such as Iowa. 



It should be at once indicated that on the whole, from the 

 point of view of making productive land available, drainage 

 has been very beneficial. It has improved tillable land and 

 has brought millions of acres of otherwise untillable land 

 some of it very productive under cultivation. But on the 

 other hand, it must also be indicated that a considerable 

 amount of this drainage has not been selective, especially 

 that of organized drainage enterprises, of which many were 

 induced by public policies to become highly speculative. 

 These have brought what have proved to be marginal and 

 even submarginal lands into use, have created many problem 

 spots in the agriculture of the United States, and in too many 

 localities have had a wide-spread unfavorable influence on 

 some of the basic hydrologic balances. 



In addition to drainage operations on behalf of agriculture, 

 other types of drainage have promoted the rushing of waters 

 unused to the seas. Modern highway and railroad construc- 

 tion includes as a basic factor of its technique an adequate 

 provision for drainage; and carefully constructed ditches 

 along the highways, and culverts wherever needed, have 



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