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brown. EFFECTS OF SOIL CONSERVATION 



[Ch. 22 



Flood erosion. Flood erosion results from the scouring action of 

 flood-water overflow on the surface of flood plains and alluvial fans. 

 As in stream-channel erosion, this may or may not result in a net sedi- 

 ment production (Fig. 6) . 



Construction erosion. This term is used to include all soil and earth 

 movement produced directly by construction of roads, railroads, power 



Fig. 6. Flood erosion as a result of flood-water scouring in cultivated field on 

 Ohio River flood plain after flood of January 1937. 



lines, dams, building projects, etc. It includes also the erosion result- 

 ing from lack of proper maintenance of these properties, including the 

 effects of scraping earth roads and erosion of unprotected cuts and fills 

 (Fig. 7). 



Mining and industrial wastes. This includes all forms of waste 

 dumped into streams or left in positions favorable to erosion (Adams, 

 1944) (Fig. 8). 



Some forms of natural geologic erosion do not fall strictly within a 

 single one of these classes. For example, the recession of cuesta faces, 

 or the "breaks" of the plains, are a combination of sheet erosion and 

 minor gullying, often accompanied by slumping and other mass move- 

 ments. However, a type of erosion that does not fall within a single 



