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INDIANA UNIVERSITY STUDIES 



the channel would cause the velocity to be increased, which in turn 

 would lower the channel, making it possible for it to carry more 

 water in times of flood without overflowing the banks. A de- 

 structive flood in the growing season would cause a dam.age equal 

 to the amount necessary for such improvements as mentioned above. 

 However, destructive floods in the growing season are not the rule 

 in the White River valley, but they are a possibility which is star- 

 ing the farmers in the face all of the time, and there is no way of 

 predicting just when the valley land will be flooded. In another 

 place the writers have shown that the majority of the floods in the 

 Ohio valley occur during the first four months of the year; but that 

 does not hinder the flood waters from cutting into the banks, or 

 washing the soil from the flood plain. One farmer pointed out 

 the fact that in one way, at least, the floods that come the first 

 four months are more destructive to the soil than those that come 

 in the dry summer months. If the ground is not frozen when 

 a flood comes during January, February, March or April, the ground 

 is looser than it would be in the summer months, and hence more 

 easily washed. Freezing and thawing are the causes of this loose- 

 ness of the ground. In the summer months the ground is likely 

 to be dried out and to be harder and less easily eroded. The ground 

 that is under cultivation during the summer months, of course, 

 will be badly washed. An overflow at any time of the year is sure 

 to cause a large amount of damage, but by straightening the channel 

 the increased fall will cause the current to cut the channel deeper, 

 thus lessening the need of levees, and carrying the water off in a 

 much shorter time. 



But straightening the channel does not stop bank-cutting. It 

 may mitigate it for a short time, but if that is all that is done, in 

 a short time conditions would be as bad as before. As has been 

 said, the current must not be allowed to come against the bank 

 in such a manner as to start a meander. In a straight stretch of 

 the river let no meanders get started. If they by some means 

 occur, steps should immediately be taken to keep them from growing 

 larger. Many places came under the notice of the writers where 

 rock had been thrown along the bank to prevent further bank 

 cutting. These banks, riprapped thus with refuse rock, were not 

 cut in the least by the current. At other places, piling had been 

 thrown down and brush and other debris packed in behind. Below 

 Spencer, in a very decided meander, rock jetties had been extended 

 out in the river some twelve or fifteen feet. Rock was also thrown 

 on the bank to prevent the current from cutting around the jetty. 



