57 



The Flood of March, 1913, Along the Ohio River 

 AND Its Tributaries in Southeastern Indiana. 



Glenn Culbertson. 



Upon investiiiaticdi it was found that the floods of the tributaries of 

 the Ohio River in southeastern Indiana, resulting from the unusual rain- 

 fall of March 23-27, 1913, were not so remarkable as those of the streams 

 of central Indiana and Ohio. 



Two reasons may be given for this. The first is that the precipitation 

 in the basins of the tributaries of the Ohio in southeastern Indiana dur- 

 ing the above period did not exceed seven or seven and a half inches, ex- 

 cept in very small areas. In the basin of the tributaries of the east and 

 west forks of White River the i-ainfall in places reached nine or more 

 inches during the same period. The second reason is, that while the pre- 

 cipitation was excessive, yet the heaviest showers of two or three inches, 

 coming within a period of a few hours, were sufficiently separated in 

 time to permit the "inunediate runoff" to pass into the larger streams and 

 on to the Ohio River. This was done the more readily inasmuch as the 

 gradients of the tributaries of the Ohio in this region are very high. In 

 these streams a period of a few hours only is needed to carry off an 

 excess of water that in the more level parts of central and northern Indi- 

 ana would require almost as many days. 



Two or three excessive rainfalls of this period added greatly to the 

 destructive erosion of the steep hillsides, where unprotected by forest 

 growth or other vegetation. The soil of these slopes, loosened by the 

 winter's frost and in too many cases entirely without protection, was 

 swept away by the hundreds and thousands of tons. Along with the 

 finer materials much gravel and small stones were deposited over the valu- 

 able bottom lands along the larger streams, adding greatly to this destruc- 

 tive work which has taken place during every great flood since the for- 

 ests were removed from the hills. 



The flood of the Ohio River during early April, resulting from the 

 rains of March, was not the greatest known, being exceeded by that of 



