INLAND DRAINAGE 



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proper condition — that is, keeping it in such shape that it will 

 properly drain the area it is supposed to drain and also keeping 

 it in such shape that it itself will not become a breeding place. 

 Due to local topography, character of soil and other conditions, 

 some open ditches or parts thereof may be relatively expensive to 

 keep in shape. 



Fig. 81. — Cleaning out road-side ditches with a ditching machine. 



In order to preserve their ability to drain the areas they are 

 intended to drain, ditches should be kept to the established 

 grade and proper cross-section; in order to prevent ditches from 

 themselves becoming breeding-places, obstructions, such as 

 sticks, leaves and other floatage, deposits of silt and sand and all 

 vegetable growth, including algae, should be removed from the 

 ditch periodically. Shovels and hoes are the tools best suited 

 to this work. Where the ditch is in soft ground, great care is 

 required not to spoil the grade. 



For the removal of rank grass and weeds from ditches, a weed- 



