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Channel Widening 



How We Impact Channel Width 



• Overgrazing and trampling by livestock 



• Causing any degradation of the upstream 

 banks, floodplains, or riparian areas 



• Increasing amount of sediment either 

 upstream or in immediate area 



^^» Increasing flood flows by decreasing 



^H vegetation upstream 



f • Transferring water from one stream to 



F another within the same watershed 



fc (interbasin water transfer) 



Effects of Our Impact 



• Increases bank erosion 



• Increases need to treat drinking water 

 Increases maintenance of irrigation pumps, 

 diversions, and ditches 

 Increases sediment loads, which 

 encourages erosion and widening further 

 downstream 

 Decreases vegetation 

 Decreases fish habitat by filling in pools 

 and spawning areas and by warming water 

 in summer and icing water in winter 

 Eliminates riparian habitat 



If your stream lacks pools 

 ami riffles, and seems 

 unusually shallow, it may 

 have an overly wide channel. 

 Channels begin to widen if 

 banks are trampled, 

 vegetation is removed, or the 

 channels become loaded ivith 

 more sediment than they can 

 carry. The sediment settles 

 and begins to fill the 

 channel. The same amount of 

 water is noiv trying tofloiv 

 through a smaller channel. 

 As a result, the channel 

 begins to ividen. 



Lessening Our Impact 



• Protect riparian vegetation 



• Stabilize upstream erosion by replanting 

 vegetation 



• Manage riparian areas to prevent erosion 



v#5K? ^^"^nx 



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