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Keeping the Balance 



In any given reach, a stream constantly adjusts itself. 

 It is balancing the amount of water and gradient of the 

 channel, and the amount and size of sediment. 



Any disturbance, either natural or human-caused, will 

 alter this balance. Our activities — such as modifying 

 streams, diverting or adding water, building in 

 floodplains, or removing vegetation — can limit a stream's 

 ability to maintain a balance. An unbalanced stream is an 

 unhealthy stream. 



Balance in equilibrium 



amount and size of 

 sediment 



amount of water and 

 gradient of the channel 



Erosion Isn't Always Bad 



Wi? often think of erosion as the culprit 

 that degrades streams, hut erosion is a 

 natural process. A healthy stream hank 

 may erode a small amount each year. 

 Erosion becomes destructive to streams 

 when it increases above the normal rate. 

 Then it takes land away from wildlife and 

 agriculture, and reduces the water quality 

 that fish and other aquatic life need. 

 (You'll find more information about this 

 under "Floodplains" on page 7; see also 

 page 24.) 



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