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INDIANA UNIVERSITY STUDIES 



subject will be published later. For a full discussion of the effects 

 of deforestation on erosion, see Mr. L. C. Glenn's, 'Denudation 

 and Erosion in the Southern Appalachian Region, (Professional 

 Paper, No. 72, U.S.G.S.'). 



Levees and Embankments 



One of the most interesting phases in the study of the flood 

 conditions was found in levees and embankments. We will first 

 consider the levees and the embankments as to their relation to 

 the river, their ponding effect upon the flood waters, their effect 

 upon the land, both above and below them, and the effect of the 

 high waters on the levees themselves. Then will follow a con- 

 sideration of their general effects and conclusions concerning them. 

 They will be taken up in the order in which they came under the 

 notice of the investigators in the progress of the river work. Con- 

 stant reference to the maps will help the reader to understand the 

 text. 



Morgan County. White River in Morgan County flows through 

 the exposed Knobstone sandstones and shales. Since this rock 

 structure is easily weathered and eroded, the valley is remarkably 

 wide, being from one to four miles in width. This great and valuable 

 strip of alluvial land is cut through by the conspicuosly meandering 

 river which does not tend to remain constant in its channel. As a 

 result of this latter condition, man has attempted to hold it in 

 its present channel by means of riprapping and leveeing at different 

 places along the channel. Levees, however, have not been built 

 for that purpose alone, but for protecting the alluvial soil from 

 wash and for the protection of growing crops. W^e will see with 

 what success these constructions have served their purpose. 



The first construction that came to our attention was the 

 public road extending northeast across the valley from Waverly. 

 The water was completely over the embankment which was about 

 ten feet in height in the stretch between Waverly and the cement 

 bridge, a distance of about one-eighth of a mile. On the north side 

 of the bridge it was much less in height. This was a new rock road 

 and was almost entirely destroyed, the rock being carried several 

 hundred feet below and deposited with other debris in a large bar. 

 Next to the town not only was the grade washed out, but a deep 

 hole was made.. This was because of a swirl starting from the cellar 

 of a house that was washed away. A very strong current raged at 

 this place, due to the fact that the river turns nearly a right angle 



